Ministry of Environment and EnergyNational Environmental Research Institute

NERI Technical Report no 365

Habitats and species covered bythe EEC Habitats directiveA preliminary assessment of distribution andconservation status in Denmark

National Environmental Research InstituteMinistry of Environment and Energy

NERI Technical Report no 3652001

Habitats and species covered bythe EEC Habitats DirectiveA preliminary assessment of distribution andconservation status in Denmark

Stefan Pihl & Bjarne SøgaardDepartment of Coastal Zone EcologyRasmus Ejrnæs & Erik AudeDepartment of Landscape EcologyKnud Erik NielsenDepartment of Terrestrial EcologyKarsten DahlDepartment of Marine EcologyJens Sund LaursenDepartment of Lake and Estuarine Ecology

Data sheet

Title: Habitats and species covered by the EEC Habitats DirectiveA preliminary assessment of distribution and conservation status in Denmark

Authors: Stefan Pihl1, Rasmus Ejrnæs2, Bjarne Søgaard1, Erik Aude2, Knud Erik Nielsen3, KarstenDahl4 & Jens Sund Laursen5

Department: 1Department of Coastal Zone Ecology2Department of Landscape Ecology3Department of Terrestrial Ecology4Department of Marine Ecology5Department of Lake and Estuarine Ecology

Serial title and number: NERI Technical Report no 365

Publisher: National Environmental Research Institute©Ministry of Environment and Energy

URL: www.dmu.dk

Date of publication: August 2001

Editor: Karsten LaursenReferee: Henning Noer

Layout: Helle KlareskovTranslation and proofreading: Tove Ørts Petersen, Else-Marie Nielsen & Tony Fox

Please quote: Pihl, S., Ejrnæs, R., Søgaard, B., Aude, E., Nielsen, K.E., Dahl, K. & Laursen, J.S. 2001:Habitats and species covered by the EEC Habitats Directive. A preliminary assessment ofdistribution and conservation status in Denmark. - National Environmental ResearchInstitute, Denmark. 121 pp. - NERI Technical Report No 365.Http://faglige-rapporter.dmu.dk

Reproduction permitted only when quoting is evident.

Key words: Habitats Directive, nature conservation, natural habitat types, species, conservation status

ISBN: 87-7772-628-6ISSN (electronic): 1600-0048

Pages: 121

Internet version: The report is only available as a PDF-file from NERI's homepage

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Contents

Summary 7

Background and purpose 7

Status of natural habitat types 7

Status of species 8

1 Introduction 9

1.1 Background 9

1.2 Purpose 10

2 Material and methods 11

2.1 Data for assessment of conservation status 11

2.2 Conservation status of natural habitat types 11

2.3 Conservation status of species 13

3 Conservation status of natural habitat types listed in Annex I of theHabitats Directive 17

3.1 Priority natural habitat types 17

3.1.1 1150* Coastal lagoons 173.1.2 2130* Fixed coastal dunes with herbaceous vegetation (grey dunes) 213.1.3 2140* Decalcified fixed dunes with Empetrum nigrum 233.1.4 2250* Coastal dunes with Juniperus spp. 263.1.5 6120* Xeric sand calcareous grasslands 283.1.6 6210 Semi-natural dry grasslands and scrubland facies on calcareous

substrates (Festuco-Brometalia) (*important orchid sites) 303.1.7 6230* Species-rich Nardus grasslands, on siliceous substrates in mountain ar-

eas (and submountain areas, in Continental Europe) 333.1.8 7110* Active raised bogs 363.1.9 7210* Calcareous fens with Cladium mariscus and species of the Caricion

davallianae 393.1.10 7220* Petrifying springs with tufa formation (Cratoneurion) 413.1.11 9180* Tilio-Acerion forests of slopes, screes and ravines 433.1.12 91D0* Bog Woodland 453.1.13 91E0* Alluvial forests with Alnus glutinosa and Fraxinus excelsior (Alno-

Pandion, Alnion incanae, Salicion albae) 47

3.2 Non-priority natural habitat types 49

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4. Conservation status of species listed in Annex II, IV and V of the Habi-tats Directive 50

4.1 Priority species 50

4.1.1 1113* Houting Coregonus oxyrhynchus 504.1.2 1084* Hermit Beetle Osmoderma eremita 51

4.2 Non-priority species 52

4.2.1 Mammals 524.2.1.1 Barbastelle Bat Barbastella barbastellus 524.2.1.2 Pond Bat Myotis dasycneme 534.2.1.3 Bechstein’s Bat Myotis bechsteinii 544.2.1.4 Brandt’s Bat Myotis brandtii 554.2.1.5 Daubenton’s Bat Myotis daubentonii 564.2.1.6 Whiskered Bat Myotis mystacinus 574.2.1.7 Natterer’s Bat Myotis nattereri 584.2.1.8 Nathusius’ Pipistrelle Pipistrellus nathusii 594.2.1.9 Pipistrelle Bat Pipistrellus pipistrellus 604.2.1.10 Brown Long-eared Bat Plecotus auritus 604.2.1.11 Serotine Eptesicus serotinus 614.2.1.12 Particoloured Bat Vespertilio murinus 624.2.1.13 Noctule Bat Nyctalus noctula 634.2.1.14 Harbour Porpoise Phocoena phocoena 644.2.1.15 European Otter Lutra lutra 644.2.1.16 Grey Seal Halichoerus gryphus 664.2.1.17 Harbour Seal Phoca vitulina 674.2.1.18 Dormouse Muscardinus avellanarius 674.2.1.19 Northern Birch Mouse Sicista betulina 68

4.2.2 Reptiles 694.2.2.1 European Pond Turtle Emys orbicularis 694.2.2.2 Sand Lizard Lacerta agilis 704.2.2.3 Smooth Coronelle Coronella austriaca 71

4.2.3 Amphibians 714.2.3.1 Great Crested Newt Triturus cristatus 714.2.3.2 Fire-bellied Toad Bombina bombina 724.2.3.3 Moor Frog Rana arvalis 734.2.3.4 Branching Frog Rana dalmatina 744.2.3.5 Tree Frog Hyla arborea 754.2.3.6 Common Spadefoot Pelobates fuscus 764.2.3.7 Green Toad Bufo viridis 764.2.3.8 Natterjack Toad Bufo calamita 77

4.2.4 Fish 784.2.4.1 Sea Lamprey Petromyzon marinus 784.2.4.2 Brook Lamprey Lampetra planeri 794.2.4.3 River Lamprey Lampetra fluviatilis 804.2.4.4 Sturgeon Acipenser sturio 804.2.4.5 Miller’s Thumb Cottus gobio 814.2.4.6 Twaite Shad Alosa fallax 814.2.4.7 Allis Shad Alosa alosa 824.2.4.8 Salmon Salmo salar 824.2.4.9 Spined Loach Cobitis taenia 834.2.4.10 Weatherfish Misgurnus fossilis 84

4.2.5 Butterflies 844.2.5.1 The Large Copper Butterfly Lycaena dispar 844.2.5.2 Marsh Fritillary Euphydryas aurinia 85

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4.2.5.3 Clouded Apollo Parnassius mnemosyne 854.2.5.4 Scarce Heath Coenonympha hero 864.2.5.5 Large Blue Butterfly Maculinea arion 87

4.2.6 Dragonflies 884.2.6.1 Green Club-tailed Dragonfly Ophiogomphus cecilia 884.2.6.2 Large White-faced Darter Leucorrhina pectoralis 884.2.6.3 Bulbous White-faced Darter Leucorrhina caudalis 894.2.6.4. Eastern White-faced Darter Leucorrhina albifrons 904.2.6.5 Green Hawker Aeshna viridis 90

4.2.7 Beetles 914.2.7.1 Great Diving Beetle Dytiscus latissimus 914.2.7.2 Dipping Beetle Graphoderus bilineatus 924.2.7.3 Stag Beetle Lucanus cervus 924.2.7.4 (Violet Click Beetle) Limoniscus violaceus 93

4.2.8 Snails 944.2.8.1 Geyer’s Whorl Snail Vertigo geyeri 944.2.8.2 Narrow-mouthed Whorl Snail Vertigo angustior 954.2.8.3 Desmoulins’ Whorl Snail Vertigo moulinsiana 95

4.2.9 Bivalves 964.2.9.1 Freshwater Pearl Mussel Margaritifera margaritifera 964.2.9.2 Thick Shelled River Mussel Unio crassus 97

4.2.10 Vascular plants 974.2.10.1 Little Grapefern Botrychium simplex 974.2.10.2 Yellow Marsh Saxifrage Saxifraga hirculus 984.2.10.3 Floating Water Plantain Luronium natans 984.2.10.4 Slender Naiad Najas flexilis 994.2.10.5 Lady’s Slipper Orchid Cypripedium calceolus 1004.2.10.6 Fen Orchid Liparis loeselii 1004.2.10.7 Fir Clubmoss Lycopodium selago 1014.2.10.8 Alpine Clubmoss Lycopodium alpinum 1024.2.10.9 Pursh Deeproot Clubmoss Lycopodium tristachyum 1024.2.10.10 Groundcedar Lycopodium complanatum 1034.2.10.11 Running Clubmoss Lycopodium clavatum 1044.2.10.12 Stiff Clubmoss Lycopodium annotinum 1054.2.10.13 Bog Clubmoss Lycopodium inundatum 106

4.2.11 Mosses 1074.2.11.1 Dichelyma Moss Dichelyma capillaceum 1074.2.11.2 Green Shield Moss Buxbaumia viridis 1074.2.11.3 Roger’s Bristle-moss Orthotrichum rogeri 1084.2.11.4 Meesia Moss Meesia longiseta 1094.2.11.5 Slender Green Feather-moss Hamatocaulis vernicosus 109

5 Summary assessment of data and conservation status 111

5.1 Data and conservation status of natural habitat types 111

5.2 Data and conservation status of species 113

6 References 115

National Environemtal Research Institute

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Background and purpose

Under the Habitats Directive (The Council of theEuropean Communities: Council Directive 92/43/EEC of 21 May 1992 on the conservation of naturalhabitats and of wild fauna and flora), Denmark hasdesignated a total of 194 habitats to be includedin a European network of Special Areas of Con-servation (SAC’s), Natura 2000. The designationsare based upon the presence of 60 of the naturalhabitat types listed in Annex I of the Directiveand approx. 44 of the species listed in Annex IIwhich occur within the territory of Denmark andfor the conservation of which the Communityhas a special responsibility.

The member states are obliged to monitor andassess the conservation status of these naturalhabitat types and species and to report their find-ings to the Community. To comply with theserequirements, the Danish Forest and NatureAgency, the National Environmental ResearchInstitute and the Danish county authorities haveinitiated a co-operative programme to provideand compile the data necessary to assess theconservation status of the natural habitat typesand species concerned.

The purpose of this report is to present the con-servation status of the habitats and species inDenmark on the basis of the background dataand information available. The report will beintegrated as an annex into the first Danish na-tional report in 2001.

The report focuses on a total of 13 priority natu-ral habitat types listed in Annex I and 79 specieslisted in Annexes II, IV and V of the HabitatsDirective. Many of the natural habitat types andspecies concerned mainly occur in Central Eu-rope, and Denmark frequently represents thenorthernmost boundary of their distributionalrange. On the other hand, many characteristicDanish species are not specified in the Directivelists. Hence, the results presented in this reportshould be considered as a status report in rela-tion to the Habitats Directive and not as an as-

sessment of the status of overall nature conser-vation interests in Denmark.

Status of natural habitat types

The report presents the very first assessment ofthe conservation status of Danish natural habi-tat types covered by the Habitats Directive. Theassessment is based on mapping of the naturalhabitat types in the SAC’s put forward by Den-mark. The mapping provides information on theoccurrence and extent of the natural habitattypes and the factors having positive or nega-tive impacts on their typical species.

A total of 61 natural habitat types included inthe Habitats Directive are considered to occurat present in Denmark. Thirteen of these are pri-ority natural habitat types and the mapping hasprimarily focused on these priority types whilethe remaining types have been only partiallysurveyed. Consequently the assessment of con-servation status covers the 13 priority naturalhabitat types.

The main conclusions of the assessment of theconservation status of the natural habitat typesare:

1. The basic knowledge of the distribution, thetypical species, and the structure and func-tion of the natural habitat types is in generalnot sufficient to make a reliable assessmentof their status.

2. The assessment of the conservation status de-picts a nature conservation resource that hasbeen, and continues to be seriously threat-ened by anthropogenic activities. For the 13priority types, the conservation status is con-sidered to be favourable for 2 habitats, un-certain for 6 habitats, unfavourable for 3 habi-tats, and unknown for 2 habitats.

The assessment must be considered as prelimi-

Summary

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nary because precise conservation objectives forthe natural habitat types have yet to be devel-oped.

Status of species

In the Habitats Directive, the conservation sta-tus of a species is defined in terms of all the in-fluences acting upon the species, which mayaffect the long-term distribution and abundanceof its populations. Such an assessment requiressystematically and continuously collected datain order to describe the status and developmentof the population of the species concerned aswell as its natural range and habitat.

Systematic monitoring of particular specieslisted in the Annexes of the Habitats Directivehas only been implemented in a few exceptionalcases. Studies of species status and recent dis-tribution have been carried out in a limitednumber of cases, but for the majority of speciesthis report is based on historical and recent datagathered from scattered information sources.Thus, in general monitoring data relating to in-dividual species are only available at an exten-sive geographical scale. The background datafor the 79 species assessed in this report are there-fore only considered to be satisfactory for 30species whereas the data on the remaining 49species were insufficient to enable an adequateassessment of their status and abundance.

In these circumstances and based on the dataon the total occurrence and distribution of thespecies in Denmark, the conservation status ofspecies has been assessed based on the follow-ing categories:

Favourable conservation status: 14 species in-cluding 11 mammals, 1 amphibian, and 2 fishspecies.

Uncertain conservation status: 22 species includ-ing the only 2 priority species houting (fish) andhermit (beetle), 4 mammals, 1 reptile, 5 amphib-ians, 2 dragonflies, and 8 vascular plants.

Unfavourable conservation status: 17 species in-cluding 2 amphibians, 2 fish, 2 butterflies, 1 drag-onfly, 2 beetles, 1 bivalve, 5 vascular plants, and2 mosses.

Unknown conservation status: 13 species includ-ing 4 mammals, 1 reptile, 4 fish, 3 snails, and 1mussel.

Disappeared: 13 species including 1 reptile, 2 fish,3 butterflies, 2 dragonflies, 2 beetles, and 3mosses.

The assessment is based on the preliminary clas-sification of conservation status into these fivecategories. It is expected that these will be re-defined when conservation objectives for thespecies listed in the Habitats Directive have beenestablished.

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1.1 Background

In 1992 the Council of the European Communi-ties adopted Council Directive 92/43/EEC of 21 May1992 on the conservation of natural habitats and ofwild fauna and flora, referred to in common-useEnglish as the Habitats Directive. The main aimof the Directive is to contribute to promotingbiodiversity by the conservation of habitats (natu-ral habitat types) and species of wild fauna andflora essential to the community within the Eu-ropean territory of the Member States.

The most important tool for fulfilling the aim ofthe Directive is the establishment of a Europeansystem of Special Areas of Conservation (SACs),known as the Natura 2000 network. This networkincludes the special areas of conservation des-ignated under the Habitats Directive and theareas designated under the EEC Bird ProtectionDirective. Habitat areas for certain natural habi-tat types and species are to be designated ac-cording to Annexes I and II of the Habitats Di-rective. These areas enjoy a special protectionstatus within the European Community as awhole. The species of community interest listedin Annex IV are in need of strict protection, in-cluding the prohibition of certain means of cap-ture/ killing, collection, and commercial exploi-tation.

Under the Habitats Directive, Denmark has des-ignated a total of 194 habitats for the Natura 2000network. The designation is based on the occur-rence of approx. 60 of the natural habitat typeslisted in Annex I of the Directive and approx. 44of the species listed in Annex II representedwithin the territory of Denmark. These 194 ar-eas include the majority of the 111 bird protec-tion areas designated in 1983 under the CouncilDirective 79/409/EEC of 2 April 1979 on the pro-tection of wild birds, referred to as the Bird Pro-tection Directive, and the 27 Ramsar-sites des-ignated in 1978 under the Convention on con-servation of wetlands of international impor-tance, particularly as habitats for waterfowl,known as the Ramsar Convention. According

to international protection directives and con-ventions, Denmark has thus designated a totalof approx. 10,000 km2, of which 7,020 km2 rep-resent marine areas.

Under the Habitats Directive, Member Statesshall every 6 years draw up national reports on" .. the implementation of the measures taken underthis Directive. This report shall include in particularinformation concerning the conservation measuresreferred to in Article 6 (1) as well as evaluation ofthe impact of those measures on the conservation sta-tus of the natural habitat types of Annex I and thespecies in Annex II and the main results of the sur-veillance referred to in Article 11 ..." (Article 17 (1).Denmark’s first national report will be drawnup in the summer of 2001 and will include anaccount of the designation of the 194 habitat ar-eas constituting the Danish contribution toNatura 2000 as well as information on the statu-tory and administrative conservation measuresimplemented for these areas in Denmark. Thereport will be drawn up by the Danish Forestand Nature Agency.

The Directive further states that "For special ar-eas of conservation, Member States shall establishthe necessary conservation measures .." (Article 6(1) conservation being defined as "a series of meas-ures required to maintain or restore the natural habi-tats and the populations of species of wild fauna andflora at a favourable status .." (Article 1). MemberStates shall thus take appropriate measures toensure a favourable conservation status of bothnatural habitat types and species. The definitionof the term 'favourable' as stated in the HabitatsDirective is based on a range of biological pa-rameters which collectively form the basis of as-sessing whether a certain natural habitat typeor species are reasonably protected in terms offuture conservation.

Member States are obliged to monitor habitatsand species: "Member States shall undertake sur-veillance of the conservation status of the naturalhabitats and species referred to in Article 2 with par-ticular regard to priority natural habitat types andpriority species" (Article 11).

1 Introduction

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To comply with this requirement, the DanishForest and Nature Agency, the National Envi-ronmental Research Institute and the Danishcounty authorities have initiated a co-operativeprogramme to provide and compile the datanecessary to assess the conservation status of thenatural habitat types and species concerned.

1.2 Purpose

The purpose of this report is to present the con-servation status of species and habitats basedon the background data and the informationavailable. The report will be integrated as anannex into the first Danish national report andwill include the priority natural habitat typeslisted in Annex I and the species listed in An-nexes II and IV. The non-priority natural habi-tat types and species listed in Annex V have,except for club mosses, only been considered insummary form or not at all.

The brief for compiling this report was crypticand, in practise, quite complicated. By way ofexample, the majority of the natural habitattypes specified in the Directive are defined bythe occurrence of specific plant communities.However, the individual communities gradenaturally into each other and the boundary be-tween communities is often rather arbitrary, notleast because the transition communities be-tween individual communities are not necessar-ily identical in the different European biogeo-graphic zones. Therefore, the results presentedin this report should be considered as prelimi-nary and the coming six years will undoubtedlylead to improvements in the verification andstandardisation measures within Denmark andthroughout the Member States.

Although there exists extensive information re-lating to the Danish natural environment, thereis currently no overall national programme formonitoring the terrestrial natural environmentin Denmark. This is relevant in relation to thedefinitions of 'favourable conservation status' ofboth natural habitat types and species listed inthe Habitats Directive as these definitions arealso based on distribution and abundancetrends. Geographical range, abundance and dis-tribution should thus be stable or increasing toqualify for the definition of favourable conser-vation status.

In many cases, the absence of an overall, stand-ardised monitoring programme means that, dueto lack of knowledge of the historical distribu-tion and abundance, this status report can onlypresent assessments, which can not be fullybased on representative data. For the speciesspecified in the Directive the information baseis, however, far more detailed – not least becausenational Red Lists have been prepared over anumber of years (latest Stoltze & Pihl 1998a).Knowledge of natural habitat types is less de-tailed and consistent. This report thus representsan important initial step towards (i) mapping ofDanish vegetation types and the natural envi-ronment generally and (ii) a future targeted andintegrated monitoring programme.

The report focuses on a total of 13 priority natu-ral habitat types and 79 species. Many of thenatural habitat types and species concernedmainly occur in Central Europe, and Denmarkfrequently represents the northernmost bound-ary of their distribution range. On the otherhand, many characteristic Danish species are notspecified in the Directive lists. Hence, the resultspresented in this report should be consideredas a status report in relation to the Habitats Di-rective and not as an assessment of the overallnature conservation interests in Denmark.

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2.1 Data for assessment ofconservation status

The data available on natural habitat types andspecies included in the Habitats Directive havebeen provided in a collaborative project betweenthe Danish county authorities, the Danish For-est and Nature Agency, the National Environ-mental Research Institute, and external consult-ants with the aim of assessing the conservationstatus of the natural habitat types and speciesconcerned.

Data on natural habitat types have been pro-vided by the counties and the State Forest Dis-tricts in a schematic form and supplemented byrelevant reports. For a range of priority naturalhabitat types the counties have also (to a vary-ing extent) digitised the distribution, extent andoccurrence of the priority natural habitat types,primarily based on existing sources of informa-tion. The National Environmental Research In-stitute received 490 data sheets covering the 13priority natural habitat types and 126 data sheetscovering the 46 non-priority natural habitattypes.

As for the species concerned, the counties havesubmitted a small number of data sheets pro-viding information on a relatively limited num-ber of species covered by the Habitats Directive,supplemented by a series of relevant reports. Theresults of the counties’ ongoing monitoring ofparticularly amphibians and vascular plantshave also been incorporated in the material.

On behalf of the Danish Forest and NatureAgency, the National Environmental ResearchInstitute implemented in 1998 and 1999 fieldprojects for collection of data on selected red-listed species and a wide range of species ofunknown recent distribution was studied. Sixvascular plant species, two butterfly species, andone amphibian species were covered in 1998(Wind et al. 1999). In 1999, the studies were fo-cused on the two priority species, houting andhermit beetle and five species of mosses, one

species of vascular plant, three species of whorlsnails, three species of dragonflies (NERI,unpubl. data). The following external expertconsultants have contributed to the collectionof data on the occurrence and status of species:

Houting: The Counties of Ribe and Southern Jut-landHermit beetle, stag beetle, and Limoniscus violaceus:Ole Martin, EntoConsultBats: Hans Baagøe, Zoological Museum Univer-sity of Copenhagen (ZMUC)Harbour porpoise: Finn Larsen, Danish Institutefor Fisheries Research and Carl Kinze, Zoologi-cal Museum University of Copenhagen (ZMUC)Dormouse: Helle WilhelmsenNorthern Birch Mouse: Thomas Secher Jensen,The Natural History Museum, AarhusReptiles, amphibians and snails: Kåre Fog, AmphiConsultFish: Søren Berg, Danish Institute for Fisheries Re-searchButterflies: Per Stadel Hansen and Preben Niel-senDragonflies: Ole Fogh Nielsen, EntoConsultWater beetles: Mogens Holmen, EntoConsultMosses: Karen Thingsgaard, Biomedia

NERI’s own subject-specialist departments havebeen involved in describing and assessing theconservation status of both natural habitat typesand species. When external consultants havebeen involved, the National Environmental Re-search Institute has made the final assessmentof the conservation status.

2.2 Conservation status ofnatural habitat types

Article 1 (e) of the Habitats Directive states that"conservation status of a natural habitat means thesum of the influences acting on a natural habitat andits typical species that may affect its long-term natu-ral distribution, structure and functions as well as

2 Material and methods

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the long-term survival of its typical species withinthe territory referred to in Article 2."

The latter point covers all of the EU.

"The conservation status of a natural habitat will betaken as 'favourable' when:

• its natural range and areas it covers within thatrange are stable or increasing, and

• the specific structure and functions which arenecessary for its long-term maintenance exist andare likely to continue to exist for the foreseeablefuture, and

• the conservation status of its typical species is fa-vourable as defined in (i)" (cf. Chapter 2.3 con-servation status of species).

The conservation status of a natural habitat typecan be assessed both at the individual localitylevel and at the national level. Thus, the conser-vation status of a natural habitat type may bedefined as unfavourable at a particular localitybut still, because of its status at other localities,be judged to qualify for a favourable conserva-tion status at the national level. In this report,the conservation status has been classified infour categories: 'favourable', 'uncertain', 'unfa-vourable', and 'unknown'. The categories 'fa-vourable' and 'unfavourable' have been reservedfor localities and natural habitat types unequivo-cally falling within one of the two categories.The category 'uncertain' is applied to sites andnatural habitat types where conditions suggestthat the status is or might be 'unfavourable' butwhere this status can not be definitely verifiedon the basis of existing data. The category 'un-known' is applied to occurrences and naturalhabitat types where the data available are in-sufficient to make an assessment of the conser-vation status.

Definitions of natural habitat types: To assess theconservation status it is essential that there is aconsensus of opinion on the description of theindividual types, including their range of vari-ety and boundaries to other naturally occurringhabitats. The majority of priority natural habi-tat types are defined and described based on aCentral European phyto-sociological tradition.As this tradition has never been adopted in Den-mark, mapping procedures may easily lead tomisinterpretations and differences of opinion. It

should also be noted that in contrast to phylo-genetic species, there are no equivalent clear-cutboundary lines between different natural habi-tat types, but rather gradual transitions betweentypes. This report gives a brief description of thetypes and their relationships to other naturalhabitat types. Whenever possible, it has beenconsidered whether the boundary between habi-tat types and the mapping of the natural habitattypes comply with the definitions of the Com-mission and represent a common consensus ofopinion. However, such an assessment is con-founded by the lack of substantial descriptivedocumentation in the reports received (e.g. a listof species from the classified area). In comingyears the basis for the classification of habitattypes will be better defined by a more system-atic approach to data gathering and improvedpresentation of the documentation collected.

Range: This status report is based on site reportspredominantly relating to designated SpecialAreas of Conservation (SACs), which shouldtherefore be considered as only a proportion ofthe total number of localities representing thenatural habitat types in Denmark. The repre-sentativeness of the SACs for the individualnatural habitat types has thus been estimatedto the extent possible under the present circum-stances. The availability of time series that en-able the assessment of long-term changes in thedistribution and abundance of the natural habi-tat types are highly restricted, so the assessmentof the conservation status is therefore subject tosubstantial uncertainty at this time.

Structure and functions: The assessment of thespecial conditions and the appropriate manage-ment necessary for the long-term maintenanceof a natural habitat type requires detailed knowl-edge of the historical background of each indi-vidual natural habitat type. Although there is ageneral consensus of opinion on the conse-quence of a range of impact factors (drainage,eutrophication, grazing, cutting, soil cultivation,etc.), it is still uncertain which factors are of de-cisive importance for the long-term maintenanceof the natural habitat type and the level at whichthe critical threshold of these factors has beenexceeded.

The assessment is complicated by the dynamicsof nature; succession is, for example, an integral

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part of the natural dynamics of sand dunes. Along-term conservation of the dune-ecosystemis thus dependent on disturbance that may, atintervals, set succession back to its early stages.Natural succession may also result in one natu-ral habitat type developing into another naturalhabitat type. As an example, calcareous fens maybecome overgrown with species from the origi-nal reed bed and eventually develop into an ash-alder swamp. It is more complicated to assesswhether the effects of succession are positive,negative or neutral. The general opinion is thatdevelopment from one natural habitat type intoanother is considered to be negative if it causesa significantly deterioration in the conservationstatus of the disappearing natural habitat typeat the national level, which may particularlyhappen to already rare and fragmented naturalhabitat types. These issues need to be discussedin detail when establishing overall conservationobjectives.

Generally, it is important to be aware that thecontinuity of living conditions (e.g. the mainte-nance of open habitats) is essential for the con-servation of biological diversity in a cultivatedlandscape with small fragmented biotopes andpopulations of species with a limited capacityfor dispersal. Therefore, in each instance, it mustbe considered whether the successional devel-opment is consistent with the conservation ofbiological diversity and protected natural habi-tat types at the national level.

In the present synthesis, reports on eutrophica-tion, hydrology and natural disturbances arebased on estimates and assessments and musttherefore, to a certain extent, be of a subjectivecharacter. Factors such as scrub invasion aremore easily observable, but information is stillbased on subjective reports rather than on theresults of quantitative time series. The assess-ment of the conservation status is therefore insome cases subject to great uncertainty.

Typical species: The reports provide relatively lit-tle information on the status and abundance ofthe populations and an assessment of the con-servation status of typical species has only beenpossible in exceptional cases. However, for somespecies it has been possible to document that acharacteristic flora occurred within the biotopesreported.

Conservation status: Each of the 13 priority natu-ral habitat types have been allocated a sectionin this report discussing the definition, range,structure/function, typical species of the natu-ral habitat type concerned and an assessment ofthe conservation status. Dot maps illustrate thereported localities of each habitat type. However,due to lack of data, the dot maps representingdune and forest habitat types are only markedfor those SACs, within which a certain type hasbeen recorded. The boundary between two ofthe bio-geographic regions specified in the Habi-tats Directive, the Continental and the Atlanticregion, passes through Denmark and has alsobeen marked on the maps.

2.3 Conservation status ofspecies

Article 1 (i) of the Habitats Directive states that:"conservation status of a species means the sum ofthe influences acting on the species concerned thatmay affect the long-term distribution and abundanceof its populations within the territory referred to inArticle 2." The latter point covers all of the EU.

"The conservation status will be taken as 'favour-able' when:

• population dynamics data on the species concernedindicate that it is maintaining itself on a long-term basis as a viable component of its naturalhabitats (1), and

• the natural range of the species is neither beingreduced nor is likely to be reduced for the foresee-able future (2), and

• there is, and will probably continue to be, a suffi-ciently large habitat to maintain its populationson a long-term basis (3)."

At present, these definitions can not be trans-lated into precise operational interpretations. Inthe absence of more specific definitions this re-port has applied the following criteria.

Re 1: In most cases, it is a matter of subjectivejudgement whether a population or a species (ina national context to be considered as one ormore populations) can be expected to maintain

14

itself on a long-term basis. The phrase 'long-term' does not denote any exact term of years.

The potential of a species to maintain viable pop-ulations on a long-term basis will, in the absenceof any acute threats, depend on the abundanceof the population. Everything else considered,small populations are expected to be more vul-nerable to both anthropogenic and more natu-ral stochastic and unpredictable effects thanlarge populations. Climatic fluctuations, diseaseand immigration of competing species fall intothe last category.

In practice, it is difficult to make precise estimatesof the correlation between population size andvulnerability. Within population genetics the gen-eral opinion has been that population sizes shouldexceed 500 individuals to be considered suffi-ciently robust to demographic and environmen-tal stochasticity. The limit has been subject tomany discussions and it would often seem morereasonable to use 2,000 individuals as the lowerlimit, also referred to as the Minimum Viable Popu-lation size (MVP)1 (Nunney & Campbell 1993).

Small populations will also be more exposed toinbreeding depression and genetic drift thanlarge populations. Within population geneticsthe concept effective population number is used forthe number of individuals in a population whosereproduction contributes to the next generation.The effective population number will often beconsiderably smaller that the actual population.The general theoretical opinion has been that theminimum effective population number shouldbe at least 50 individuals (for a short period oftime) to prevent inbreeding. Subsequently, how-ever, a more conservative estimate has definedthe minimum to be 500 individuals (Nunney &Campbell 1993).

In most cases, the effective population numbercan not be estimated on the basis of the dataavailable, but it should be emphasised that inpractise the effective population number maybe considerably smaller than the number of in-dividuals observed. That means that the lattermay give the impression of a larger and moreviable population than is actually the case.

In this report the following criteria have formedthe basis for assessing the conservation statusof a species.

• Number of localities hosting populations of thespecies. As an example, species occurring atless than 10 localities are assessed to be morevulnerable than species occurring at for in-stance more than 100 localities.

• Number of individuals in each population. As-sessments are here based on the concept Mini-mum Viable Population size (MVP). Depend-ing on the species concerned and its biologyMVP is estimated to be 1,000 - 2,000 individu-als.

• Isolation level of the individual populations. Iso-lation for instance will increase the risk ofinbreed and genetic drift.

• Other ecological features of the species (disper-sal capacity, population dynamics, etc.)

Re 2: The meaning of the term 'natural range' isneither precise nor clearly comprehensible. Byway of example, several species listed in theAnnexes of the Habitats Directive mainly occurin Central Europe and the Danish occurrencesare therefore often representing the northern-most boundary of their natural range, wherepopulations can, in certain cases, probably onlybe maintained by immigration. For pragmaticreasons, this report primarily refers to the ac-tual range as a synonym for the natural range.Depending on the quality of data available, theactual range within the latest 20 - 80 years hasbeen assessed. The concept 'natural range' willbe considered later in relation to the establish-ment of conservation objectives.

Re 3: The extent of available habitat must be con-sidered as relative to the species concerned. Inthis report 'habitat extent' is assessed on the ba-sis of the population size.

From these definitions it appears that conserva-tion status can not merely be seen as a functionof the abundance of a species. Relatively rarespecies may thus have a favourable conserva-tion status whereas a relatively common speciescan be judged to be of unfavourable conserva-tion status if its populations are decreasing.

1 Minimum viable population, i.e. the smallest population size making the species viable / not being extinctfor a certain period of time in a certain area (Shaffer 1981).

15

Systematic monitoring of particular specieslisted in the Annexes of the Habitats Directivehas only been implemented in a few exceptionalcases. Studies of historical status and recent dis-tribution have been carried out for a limitednumber of species but for the majority of spe-cies this report is based on anecdotal historicalinformation and scattered information sources.The assessment of the precise conservation sta-tus of a species is thus based on variable infor-mation and comprehensive adjustments are tobe expected when drawing up future reports assuch assessments can be based upon improveddata from actual monitoring programmes de-signed for the particular needs of the species anda full assessment of their habitats.

For this purpose, the National EnvironmentalResearch Institute has designed a scale servingas a tool for a summary assessment of the con-

servation status of populations of flora and faunaspecies at locality level and national level (Table2.3.1).

Assessment of conservation status: Where the dataavailable are sufficient, the conservation statusof a species has been assessed at both localitylevel and at national level.

The terms localities/habitats are here been gen-erally used for habitats where a species has beenrecorded and where it is certain or probable thatit will reproduce. Occasional occurrences of spe-cies showing no sign of reproduction in a par-ticular habitat have not been considered. Par-ticularly in the case of bats and other speciesranging over large areas, it has proved difficultto determine the factors relating to a certain lo-cality, which constitutes a suitable habitat forsuch species. Many species need several types

Table 2.3.1. Scale for a summary assessment of conservation status of populations of flora and fauna speciesat locality level and national level.

Scale Definition at locality level Definition at national level

Favourable The population of the locality is stable orincreasing in number and distribution and thehabitat is sufficiently large to ensure acontinuous maintenance of the populationwithin the locality.

The national population size of the species isstable or increasing and the habitats aresufficiently large and abundant to maintainthe populations of the species on a long-termbasis.

Uncertain The population of the locality can be stable,increasing or decreasing. If the population isstable or increasing, it is so small that it isuncertain whether the habitat is sufficientlylarge to ensure a continuous maintenance ofthe population within the locality. Or thedevelopment may be subject to uncertaintydue to lacking/past data and actual/potentialnegative influencing factors acting on thespecies within the locality.

The national population size of the speciescan be stable, increasing or decreasing. If thepopulation is stable or increasing, it is sosmall that it is uncertain whether the habitatsare sufficiently large and abundant to ensurea continuous maintenance of the populationin Denmark. Or the development may besubject to uncertainty due to lacking/pastdata and actual/potential negativeinfluencing factors acting on the specieswithin essential habitats. Or the species isrelatively common but is / appears to bedecreasing in parts of its natural range.

Unfavourable The population of the locality is decreasing inboth number and distribution and the habitatis not sufficiently large to ensure a continuousmaintenance of the population within thelocality.

The population size of the species isdecreasing and the habitats are notsufficiently large and abundant to maintainits population on a long-term basis.

Unknown No, very little and / or very uncertaininformation is available on the occurrence ofthe species within the locality and it isunknown whether the habitat is sufficientlylarge to ensure a continuous maintenance ofthe population within the locality.

No, very little and / or very uncertaininformation is available on the nationaloccurrence of the species and it is unknownwhether the habitats are sufficiently large andabundant to maintain the Danish populationon a long-term basis.

Disappeared The species is no longer found within thelocality despite repeated searches over a longperiod of years.

The species is no longer found in Denmarkdespite repeated searches over a long periodof years.

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of localities. Bats, for instance, need access toappropriate breeding localities, foraging areas,and wintering localities in suitable proximity.

The national status is assessed on the basis ofthe status at the individual localities. The theo-retical background for an assessment of the con-servation status is the total occurrence and dis-tribution of the species in Denmark. The biologi-cal features, distribution and population size ofthe species in Denmark, the development of thepopulation and the overall assessment of its con-servation status appear from the text, figures andtables in the individual species sections. In thetables, localities are classified in the different con-servation categories and as far as possible thepercentage of the species’ total occurrence at thelocalities associated with the individual catego-ries is also specified.

The categories 'favourable' and 'unfavourable'are exclusively applied to species where suffi-cient data are available to substantiate the as-sessment according to the scale in Table 2.3.1.

The category 'uncertain' has been introduced be-cause the background data available for com-parison with the recent status will often be basedon fragmentary historical data. Monitoring ofmost species has generally yet to be imple-mented and time series for distribution andnumber of the species are only available to a verylimited extent. For these reasons, NERI has, atpresent, found no basis for replacing this cat-egory by sub-divisions of the unfavourable sta-tus (unchanged, regenerating or degenerating).Furthermore, species may be classified in thiscategory irrespective of population developmentwhen the population is so small that its long-term survival is uncertain. This applies in par-ticular if the supporting data are uncertain / out-of-date or if the species has been subject to nega-

tive impact factors. Finally, this category includesseveral relatively common species that in partsof their natural range are or appear to be de-creasing.

The category 'unknown' is used for specieswhere only little or no information on distribu-tion and abundance is available. Species con-cerned may be those that are difficult to deter-mine or relatively common species where theidentification of their conservation status wouldrequire the introduction of a specific monitor-ing programme.

In this context the species particularly difficultto manage are those species which are knownfor certain or in all probability to have disap-peared from a locality or from Denmark. De-pending on the biology of the species and thedistance to the localities or countries where thespecies is occurring, the prospects of re-immi-gration of the species will vary. In practice, thiswill, in all likelihood not occur without artifi-cial re-introduction. To define a certain speciesas 'disappeared' implies that despite repeatedtargeted searches, the species has not been re-discovered in Denmark over a long period ofyears (cf. definition in the 1997 Red List, Stoltze& Pihl 1998a). In practise, it can be extremelydifficult to estimate whether a species has in-deed completely disappeared. The publicationof red lists has in many European countries re-sulted in rediscoveries of species regarded as dis-appeared. The results are very likely due to in-creased search activities for these particular spe-cies.

Species which have decreased in Denmark dur-ing the last 20 years or species, for which, Den-mark has a special responsibility are definedaccording to the 1997 Amber List (Stoltze & Pihl1998b).

17

Annex I of the Habitats Directive includes thosenatural habitat types of community interestswhose conservation requires the designation ofspecial areas of conservation. In Denmark thereis a total of approximately sixty of the naturalhabitat types listed in Annex I.

Note that on the maps of the natural habitattypes the close proximity of sites may result inthe overlap of one or several dots.

3.1 Priority natural habitattypes

Thirteen of the natural habitat types in Denmarkare priority (*) natural habitat types for the con-servation of which the Community has particu-lar responsibility (Table 3.1).

An assessment of conservation status of prior-ity natural habitat types in Denmark at national

level and at locality level is presented in Table3.2.

Localities are shown as dark dots on the mapsof the following natural habitat types. Note thaton the maps the close proximity of sites mayresult in the overlap of one or several dots.

3.1.1 1150* Coastal lagoons

Description

The classical description of a lagoon is a marinearea, which has been cut off from the sea by atongue of land or an isthmus formed by alluvialsand deposits produced by currents and/orwave action. If material is constantly being de-posited, the coastal lagoon will eventually becompletely separated from the sea and turn intoa landlocked lagoon liable to become overgrownwith reed and develop into a beach reed swamp.Conversely, the deposits may vary making thelagoon alternately open or closed.

3 Conservation status of natural habitat types listedin Annex I of the Habitats Directive

Code Habitat types

1150 *Coastal lagoons

2130 *Fixed coastal dunes with herbaceous vegetation (grey dunes)

2140 *Decalcified fixed dunes with Empetrum nigrum

2250 *Coastal dunes with Juniperus spp.

6120 *Xeric sand calcareous grasslands

6210 Semi-natural dry grasslands and scrubland facies on calcareous substrates (Festuco-Brometalia)(*important orchid sites)

6230 *Species-rich Nardus grasslands, on siliceous substrates in mountain areas (and submountain areas inContinental Europe)

7110 *Active raised bogs

7210 *Calcareous fens with Cladium mariscus and species of the Caricion davallianae

7220 *Petrifying springs with tufa formation (Cratoneurion)

9180 *Tilio-Acerion forests of slopes, screes and ravines

91D0 *Bog woodland

91E0 *Alluvial forests with Alnus glutinosa and Fraxinus excelsior (Alno-Pandion, Alnion incanae, Salicon albae)

Table 3.1. Priority (*) natural and semi-natural habitat types in Denmark. The code corresponds to the Natura2000 code.

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In the Interpretation Manual (Skov- og Natur-styrelsen 1999a) coastal lagoons are defined asareas with stagnant sea water of varying watervolume and salinity, wholly or partially sepa-rated from the sea by sand banks, shingle, orless frequently, by rocks. Salinity may vary agreat deal depending on rainfall, evaporationand the addition of fresh seawater from storms,temporary flooding of the sea in winter or tidalexchange. Coastal lagoons may either be with-out vegetation or with vegetation of Ruppieteamaritima, Potametea, Zosteratea or Charetea com-munities. Small lagoons and landlocked lagoonsconsidered to be the Baltic variety of coastal la-goons are small, usually shallow and more orless delimited water bodies still connected to thesea or have been cut off from the sea very re-cently by land upheaval. This type is character-ised by well-developed reedbeds along thebanks, luxuriant vegetation of submerged plantsand by having several of the morphological andbotanical development stages characteristic ofthe succession process from sea to land.

Coastal lagoons are very dynamic natural habi-tat types representing many successional stagesfrom newly formed semi-open cut-offs along thecoast to overgrown landlocked lagoons eventu-ally developing into coastal saltmarshes / in-land salt-basins (Natural habitat type 1310. Veg-etation of Salicornia and other annuals colonis-ing mud and sand).

Natural range

A total of 111 coastal lagoons have been includedin this status report. Some of these are smalllandlocked lagoons (< 1ha), which are heregrouped according to their geographical range.The result is that this status report includes 64coastal lagoons distributed between 22 SpecialAreas of Conservation (SACs) assessed to beparticularly worthy of conservation under theHabitats Directive (Fig. 3.1.1). In all, the areascover 15,504 ha.

Habitat code

Area(ha)

No. oflocalities

Conservation status of localities National con-servation statusFavourable Unfavourable Uncertain Unknown

1150 15504 64 12 7 16 29 Unfavourable

2130 6984 82 0 61 21 0 Uncertain

2140 10777 47 6 41 0 0 Uncertain

2250 336 15 14 0 0 1 Favourable

6120 33 21 6 15 0 0 Uncertain

6210 284 22 5 17 0 0 Uncertain

6230 245 35 11 17 7 0 Unfavourable

7110 3375 22 1 0 20 1 Unfavourable

7210 270 32 17 14 1 0 Uncertain

7220 103 36 0 0 26 10 Uncertain

9180 593 20 13 2 0 5 Unknown

91D0 1095 27 16 0 4 7 Favourable

91E0 662 65 36 17 0 12 Unknown

Table 3.2. Conservation status of priority natural and semi-natural habitat types in Denmark. The code corre-sponds to the Natura 2000 code.

Figure 3.1.1. Coastal lagoons (1150). Reported occur-rences of the natural habitat type in Denmark. Theboundary between the Atlantic region and the Conti-nental region is shown on the map.

19

According to the Danish Forest and NatureAgency’s descriptions of the designated natu-ral habitats, there is an estimated total area of45,800 ha of coastal lagoons in Denmark. Thiscorresponds closely with the area of coastal la-goons listed in the European Environment Agen-cy’s CORINE (Corine Biotopes Manual 1992)mapping, excluding Limfjorden (45,355 ha)(Anon. 1993). The extent of coastal lagoon areaprovided by the Danish counties for this statusreport is not strictly consistent with theCORINE mapping. The latter for instance in-cludes Ringkøbing Fjord, Dybsø and Karre-bæksminde Fjord as well as Saltvandssøen (lo-cated behind the Wadden Sea dike at Tønder-marsken), all of which could be characterisedas lagoon habitats.

Structure and function

This status report is based on the data sheetsand questionnaires submitted to the countiesand other sources, including NOVA (Danish A-quatic Monitoring and Assessment Programme)reports, local knowledge of a range of coastallagoons and phone call enquiries to some of thecounties. The conservation status of the coastallagoons has been assessed on the basis of theirstructure and functions. The structure is de-scribed in physical terms: opening to the sea (ca-nal, sluice, ditch, none), water exchange, salin-ity variations, depth, oxygen, sediments, catch-ment area and its degree of cultivation in rela-tion to potential nutrient salt depositions andthe distribution of structure-forming vegetation(e.g. Zostera, eelgrass and Potamogeton,pondweed). The ecological condition of thecoastal lagoons is described in terms of a widerange of biological conditions such as the occur-rence of particularly species of high conserva-tion interest, occurrence and distribution of char-acteristic species (phanerogams and macroal-gae), depth limits for submergent vegetation,and the ratio between primary producers (pha-nerogams/perennial macroalgae/eutrophic ma-croalgae/plankton), and benthic fauna commu-nities affected by oxygen depletion.

The eutrophication-related parameters figuringin the description of both structure and func-tion are basic parameters measured as part ofthe nation-wide marine monitoring programme

(Anon. 2000) and are integrated in the annualreport on the state of the marine environment(e.g. Markager et al.1999). Many regional sur-veys and nature monitoring programmes arebased on the same concept as the Danish AquaticMonitoring and Assessment Programme. Atpresent, nature quality criteria for marine areasthat can be directly integrated into the assess-ment of the structure and function of the habi-tats are not available. However, a system of com-mon standards at regional and national levelshas been established based on 11 years experi-ence gained from the marine monitoring pro-grammes Action Plan on the Aquatic Environ-ment, Action Plan on the Aquatic Environment2, and the present Danish Aquatic Monitoringand Assessment Programme. This standard ref-erence forms the basis for assessing the qualityof coastal lagoons.

The natural habitat type Coastal Lagoons em-braces many stages of geomorphological andseral succession. To assess the conservation sta-tus of the coastal lagoons in terms of their suc-cessional status it has been appropriate to clas-sify them into four major types. The classic la-goon types are former marine areas, which havebeen cut off (wholly or partially) from the seaby an isthmus formed by alluvial deposits fromthe sea. In addition, we define coves as lagoons(which can be considered as small fjords) en-closed from the sea behind spits of land butwhich still maintain an open connection to thesea. Landlocked lagoons are former lagoons nowcompletely cut off from the sea and salt-waterincursion only occurs through permeation or onparticularly high tides. Finally, some areas havebeen embanked and water exchange is oftenregulated by a sluice gate, only allowing salt-water incursion through leaks in the sluice andby permeation through the dam. The lagoonsincluded in this review comprise 13 embankedareas, 18 classic lagoons, 9 coves, and 24 land-locked lagoon structures (Tables 3.1.1.1 and3.1.1.2). The conservation status of these areashas been assessed based on this physical classi-fication and the resulting biological conditions.By way of example, a landlocked lagoon withlimited submergent vegetation may be assessedto have a favourable conservation status where-as coastal lagoons having a good water exchangemust fulfil much stricter demands to qualify fora favourable conservation status. One of the cri-

20

teria is e.g. an extensive depth distribution ofsedentary bottom vegetation.

Conservation status

The general conservation status of coastal la-goons is considered overall to be unfavourable(Table 3.2). The range of coastal lagoon habitatsin Denmark is not considered to be endangered.The embanked areas have all been designated

protected areas or refuges. Agreements to en-sure environment-sensitive agriculture have of-ten been established on adjacent cultivated ar-eas, including restrictions on the application offertilisers. The coves also contribute to the long-term maintenance of the distribution of thisnatural habitat type. The embanked areas andcoves represent 34% of this natural habitat type.The classic coastal lagoons and the landlockedlagoons make up the remaining 66% represent-ing the more dynamic part of this natural habi-tat type. Almost all of the present landlockedlagoons are protected under Section 3 of the Pro-tection of Nature Act whereas only 4 of the clas-sic lagoons are protected or designated refuges.A few landlocked lagoons are facing a conver-sion into beach reed swamps thus being trans-formed into another natural habitat type. At thenational level, the distribution of this naturalhabitat type is not threatened.

Ecological conditions in the coastal lagoons aremore variable. Only in approximately 20% of theareas can the conservation status of coastal la-goons be considered favourable. The unfavour-able status is primarily due to the scant occur-rence of bottom vegetation and the seasonalgrowth of plankton algae or eutrophication-re-lated macroalgae. In most landlocked lagoons,there is no submergent vegetation and many areat the stage of being overgrown with commonreed and transformed into beach reed swamps.In the embanked areas the sluice and the lim-ited water exchange make the areas extremelysensitive to the effects of land-use in the catch-ment areas. Where no environment-sensitiveagricultural agreements exist and the leachingand discharge from individual farms continue,blooms of planktonic algae and eutrophication-related macroalgae persist. Based on sitenumber, the conservation status is consideredfavourable at 19% of the localities, uncertain orunfavourable at 36% of the localities. In almosthalf of the localities (45%) it was not possible toassess the status because of insufficient data. Interms of area only 21% of the coastal lagoonshave a favourable conservation status, aroundhalf of them have an unfavourable conservationstatus and for 22% of the area it has not beenpossible to assess the status due to lack of data.The difference between numbers and area is be-cause the lack of data is most pronounced in thesmall areas.

Counties

No. of localities

TotalI L N S

Fyn 3 8 2 9 22

Ringkøbing 1 1

Roskilde 1 1

Storstrøms 3 3 2 8

Sønderjylland 2 2 2 6

Vejle 1 2 3

Vestsjælland 1 1 2 4

Viborg 9 1 7 17

Århus 2 2

Total 13 18 9 24 64

Table 3.1.1.1. Distribution of coastal lagoons betweencounties. I = Reclaimed areas, L = Classical lagoonsformed by alluvial sand deposits produced by thesea; N = Cove; S = Landlocked lagoons (groups ofcoastal lakes).

Counties

Sum of areas (hectares)

Total

Fyn

Ringkøbing

Roskilde

Storstrøms

Sønderjylland

Vejle

Vestsjælland

Viborg

Århus

Total

I

49

1541

2417

4007

N

42

610

426

1553

2631

S

131

5

23

6

161

4

330

1608

5933

196

1466

531

26

3159

2581

4

15504

1386

5933

196

851

82

20

65

3

8536

L

Table 3.1.1.2. Distribution of areas of coastal lagoonsbetween counties. I = Reclaimed areas, L = Classi-cal lagoons formed by alluvial sand deposits pro-duced by the sea; N = Cove; S = Landlocked la-goons (groups of coastal lakes).

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3.1.2 2130* Fixed coastal dunes withherbaceous vegetation (greydunes)

Description

Fixed dunes are colonised by a more or lessclosed vegetation carpet of perennial grasslands,herbs, and luxuriant vegetation of lichens andmosses. This natural habitat type is just part ofthe dynamic process of coastal ecosystems whichexists because of the natural occurrence of sand-dune blowouts, breaches and sand drift. Anacidification gradient exists, extending from thegreen to the grey dunes. The grey dunes repre-sent a typical lichen-dominated habitat requir-ing a certain level of continuous disturbance tomaintain a competitive edge over mosses andvascular plants. The dynamics of the grey andgreen dunes is more pronounced than in thedecalcified fixed dunes of the Empetrum nigrumtype (2140). The leached and acidified greydunes are more abundant than the more fertilegreen dunes.

The nutrient content, the calcium content andsand-grain size are the predominant factors de-termining the capacity of the sand to retain wa-ter, and these features vary considerably be-tween different parts of Denmark. In northwestJutland, the chain of calcareous cliffs along thecoast gives rise to sand of relatively high nutri-ent and calcareous content, which affects theplant communities of the adjacent dunes. Alongcoasts of northern Zealand, the sand is gener-ally more coarse-grained than along the westcoast of Jutland, and this fact is important forthe capacity of the sand to retain water. Precipi-tation also differs between the west coast of Jut-land and northern Zealand. During the 30-yearperiod from 1961 to 1990, the mean annual pre-cipitation was 750-900 mm in western Jutlandcompared to 550-600 mm in northern Zealand(Frich et al. 1997).

The green dunes of northwest Jutland are uniquein Europe, since their vegetation is characterisedmore by sub-continental species than in morewestern European dune habitat types (Bruun &Ejrnæs, in press).

Natural range

This habitat type is most abundant in the west-ern part of Denmark, forming an almost unbro-ken belt along the west coast of Jutland. Theoccurrence of grey dunes is considerably morerestricted to the east coast of Jutland and theDanish islands.

Reports submitted relate to 82 occurrences to-talling 6,984 ha (70 km2) distributed on 30 SACs(Fig. 3.1.2). The largest inter-connected areas rep-resenting this natural habitat type in Denmarkare all included in the SACs. Outside the SACs,this type is also widely represented in extensivesummer recreational areas.

Structure and function

The long-term maintenance of this natural habi-tat type primarily depends on conservation man-agement measures aimed at maintaining anopen natural habitat. Since the beginning of the16th century, local authorities have tried to curbthe extent of sand drift by, for example, impos-ing restrictions on the general grazing of thedunes. This continued until the 20th century anddid not completely cease until after the Second

Figure 3.1.2. Fixed coastal dunes with herbaceous veg-etation (2130). Special Areas of Conservation with re-ported occurrences of the natural habitat type in Den-mark. The sites are centred in the Special Areas of Con-servation. The boundary between the Atlantic regionand the Continental region is shown on the map.

22

World War. Grazing inhibited the growth ofbushes and trees and created local breaches re-sulting in drifting sand. A wide range of meas-ures such as planting, dune stabilisation, coastalprotection and prohibition of grazing has formany years imposed some level of physical sta-bility on the coastal landscapes at the expenseof natural dynamic processes typical of this natu-ral habitat type. Tree and scrub growth has beenrecorded at more than 50% of the localities in-cluding moderate to heavy overgrowth at morethan 25% of the localities.

Woody plants occupying the green and greydune zones are the imported mountain and dunepines and the native European aspen, oak, seabuckthorn, and Scotch rose. From many locali-ties, there have been reports on growth of sloe,broom, gorse, and Rugusa rose. At two locali-ties, bracken is cut and removed, and at one lo-cality a campaign to eradicate giant cow pars-nip has begun. In the site with bracken, peat cut-ting is considered to be necessary to maintainlocal diversity. The reports received do not indi-cate whether clearing is going on or if there is aneed for clearing.

Forty-five percent of all the localities are nowa-days being grazed to some extent. Reports re-ceived do not specify for how long the areas havebeen grazed and monitoring activity has onlybeen reported from 17% of the localities. Never-theless, all grazed localities are supposed to beinspected on a regular basis. At 50% of the re-ported localities, serious erosion has been re-ported, at a further 33% of localities, the erosionis estimated to be of minor importance. Of the50% of reported cases, erosion was consideredto have a negative impact, whilst in 20% ero-sion was considered positive. There is heavypressure on the habitat in areas bordering cen-tres of tourism. In the white and grey/greendune zones, the number of path networks is in-creasing, occasionally resulting in entire sectionsof dunes being blown away, which may have ahighly destructive effect on the coastline. Con-versely, such sea breaches might, however, alsocontribute to restoring the patterns of vegeta-tion dynamics in the dunes.

Although ammonium deposition has not beenrecorded as a direct threat to this natural habi-tat type, an assessment of the impact of the in-

creased nitrogen load will require long-termmonitoring. In the Netherlands, where levels ofnitrogen deposition is considerably higher, ob-servations have revealed comprehensive dam-age to lichens in the dry sand heaths and a tre-mendous growth of mosses at the expense oflichens. In Denmark, current levels of nitrogendeposition lie close to the critical load for lichens,suggesting that changes might only be notice-able in the long term (Tybirk & Jørgensen 1999).

Observations in Denmark have found damageto species of reindeer mosses, which could pos-sibly be due to the impact of nitrogen deposi-tion (Søchting 1990). In the early 1990s blacken-ing of reindeer mosses was observed in near-shore areas.

In the Netherlands an increase in the dominanceof mosses has been observed in dry sand heaths.The invasive moss species, Campylopus introflex-us, is one of several moss species said to colo-nise dune systems at the expense of lichens be-cause of the intensified eutrophication. Campy-lopus introflexus is considered to present a greaterthreat to the green and grey dunes than in thedecalcified fixed dunes, type 2140 (U. Söchting,pers. comm.), since mosses generally have anefficient dispersal rate and are highly competi-tive.

Typical species

Strong gradients typically characterise this habi-tat type, depending on the salt and calcium con-tent of the soil. The outlying part of the greendunes will frequently be dominated by annuals(Bromus hordeaceus, Phleum arenarium, Erophilaverna, and Cerástium semidecandrum). Furtherinland leaching, accumulation of organic mat-ter and acidification will change the plant com-munities towards more dwarf shrub heathland.The characteristic green dunes are very rich inspecies and host typical species like Pulsatilla pra-tensis, Sedum acre, Galium verum, Lotus cornicula-tus, Tymus serpyllum, Vicia cracca, Geranium san-guineum, Artemisia campestris, Pimpinella saxifra-ge, Koeleria glauca, and Silene otites. In northwestJutland, green dunes support a wide range ofdwarf species, although few species dominateindividual communities. The most dominantspecies in the green dunes are Ammophila arena-

23

ria, Poa pratensis, Achillea millefolium, Carex ni-gra, Armaria maritima, Veronica chamaedrys, Fe-stuca rubra, and Galium verum. Frequently woodyplants like Salix repens, Rosa pimpinellifolia, andHippophae rhamnoides occur.

The grey dunes are poorer in vascular plants andthey typically host acid-soil species like, for ex-ample, the two dominant monocotyledons, Ca-rex arenaria and Corynephorus canescens. Green-dune species also occur, but more lichens domi-nate large areas. The occurrence and distribu-tion of lichens mainly depend on the microcli-mate, instability of the substrate and competi-tion from the higher plants. The establishmentof new areas appropriate for the spread of lichensis dependent on continuous disturbance, includ-ing the creation of areas of bare substrate.

Conservation status

The conservation status of the natural habitattype 2130 is considered to be uncertain (Table3.2). In many areas, coastal protection and dunestabilisation have reduced the level of environ-mental instability, and this has contributed toseral succession and overgrowing of vegetationdue to cessation of grazing (particularly in thegreen dunes), increases in atmospheric nitrogendeposition and invasive species.

In areas with low rates of nitrogen deposition(< 8 kg N ha-1 year-1) like Læsø and Anholt andthe coast of northern Zealand, the load is notconsidered to constitute a threat. Repeated sur-veys of botanical test plots on Læsø showedpractically no vegetation changes over a 45-yearperiod (Christensen 1989). However, in theseareas the invasion of non-native species like Pi-nus montana and Rosa rugosa is still a threat. Forthe other areas, the present levels of depositionare close to the calculated critical load and thelong-term stability of this vegetation type istherefore uncertain. Sporadic studies indicateda growing dominance of mosses at the cost oflichen cover and it can not be ruled out that theexpanding distribution and abundance of Cam-pylopus introflexus is related to the increase innitrogen deposition.

A positive contribution to dune management isthe Nature Management Strategy of the Danish

Forest and Nature Agency (Skov- og Natursty-relsen 1999b), which provides for new possibili-ties to support the natural dune vegetation dy-namics and ensures that the natural landscape-forming processes will be accepted in the pub-lic areas to a far higher extent than has been thecase previously.

The overall assessment of the conservation sta-tus must be characterised as less than certain,as there is no information relating to the long-term impact of nitrogen deposition on this veg-etation type nor to the level of sand drift requiredto ensure the long-term perpetuation of thisnatural habitat type. There is no systematic in-formation on the impact of grazing available atpresent.

3.1.3 2140* Decalcified fixed duneswith Empetrum nigrum

Description

In general, coastal heaths are far more variedthan inland heathland, a feature attributable tothe greater variety of physical factors affectingvegetation processes. The occurrence of decal-cified fixed dunes ranges from gravelly, stonybeach ridges with more or less superposed shift-ing sands through wet dune slacks betweendunes to dry wind-swept dunes. In the pastheather was dominant in the fixed dune heath-land but nowadays crowberry is the dominantspecies. Botanical descriptions of an older daterefer to the 'fixed dune heathland' as very opendunes behind the green dunes, mainly domi-nated by heather.

The traditional use of these landscapes withcommon dune grazing stopped approximately50 years ago. In the last 150 years, drifting sandhas been efficiently eliminated by reforestation,restricted grazing, mowing and peat cutting,planting of marram grass, anti-erosion features,and coastal protection engineering. Before sheepgrazing stopped, the areas included in this natu-ral habitat type were far more dynamic, featur-ing many areas of bare substrate. At the sametime, the forests have advanced and certaincoastal areas have been so heavily urbanised thatcompletely undisturbed dune landscapes are

24

becoming rare. Quite a few of the localities re-corded represent mixtures between type 2130and type 2140 with some mires and fens occur-ring. In areas with disturbance, wind breachesand dune blowouts are often frequent (type 2120,white dunes).

As this natural habitat type is growing on shift-ing sands it represents, as is the case for all near-shore areas, a relatively young ecosystem. Thesoil characteristics of decalcified fixed duneheathland dominated by crowberry have beenstudied at many localities, and in general thesoil in coastal dune areas is less than 300 yearsold. This fact should be considered when assess-ing the stability of local conditions. A detailedDanish research project has shown that there isa gradual formation of the sour humus layer,which plays a central role in the nutrient circu-lation of this natural habitat type, and conse-quently in patterns of vegetation succession(Nielsen et al. 1999, Nielsen et al. in press). Thepresent vegetation composition is therefore theresult of the cessation of extensive grazing man-agement, increased seed dispersal from the duneplantations and (since the early 1970s) the in-tensification of atmospheric deposition of nitro-gen.

Natural range

This natural habitat type occurs mainly in thewestern part of Denmark, especially in an al-most unbroken belt along the west coast of Jut-land. Smaller areas occur on the east coast ofJutland and on the Danish islands. The total ex-tent of geomorphological shifting sand areaalong the coast extends to 1,270 km2 (Ovesen1998). Only 4.6% of this area is found on the is-lands. The extent of actual coastal heathlandwith no large and dominating built-up areas hasbeen calculated to amount to 327 km2 (Emsholm1992).

Altogether 47 reported localities are distributedbetween 21 SACs (Fig. 3.1.3). The total recordedarea representing this natural habitat type is10,777 ha (~108 km2). The extent of this habitattype within the SACs represents only a moder-ate part of the total national resource. The typecan also be found in large areas outside the SACsand it is prevalent in the large recreational sum-

mer cottage areas at the west coast. There is evenan increase in the extent of this habitat as com-prehensive sewerage and lowering of ground-water levels (through drainage) have reducedthe extent of wetland natural habitat types,many of which have now been converted todwarf shrub heathland.

Structure and function

The long-term maintenance of this natural habi-tat type is reliant upon management measuresaimed at removing nutrients and preventingovergrowth of trees and bushes. During most ofthe period in which this natural habitat type hasexisted in Denmark, it has (according to histori-cal sources) been utilised for grazing. Grazinghas only been continuous in Skallingen. For allother areas there is no reported information onthe duration and intensity of grazing. Anotheressential precondition for this type is related tocoastal protection and dune stabilisation, as pro-tection at one locality will affect the quantity ofsand elsewhere. It is very difficult to commenton the likely natural structure of a Danish coastallandscape today. The picture might very welldepend on whether the coastline is receding orwhether it is accreting because of the availabil-ity of alluvial sand deposits.

Figure 3.1.3. Decalcified fixed dunes with Empetrumnigrum (2140). Special Areas of Conservation with re-ported occurrences of the natural habitat type. The sitesare centred in the Special Areas of Conservation. Theboundary between the Atlantic region and the Conti-nental region is shown on the map.

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In the absence of man, the coastline of the westcoast would in some areas be dominated by for-est, which would have stabilised the sand andresulted in a quite different formation of thecoastal landscape. The question of how close tothe contemporary coast the forests might haveexisted can not be answered nowadays.

In western Jutland, the forests have been clearedfor thousands of years. The coastline has beenconverted into a treeless landscape not capableof affecting wind patterns. The Little Ice Age,which started in the 1500s and culminated dur-ing the Dano-Swedish Wars around 1660, causedthe recession of sea levels, creating a very widesand beach exposed to the wind. The overgraz-ing in the dunes more or less coincided with theLittle Ice Age, and probably explains the exist-ence of today’s bare, shifting sand areas. In lo-calities with sedimentary sand as e.g. Anholt thetype probably exists as a temporary successionstage towards woodland, since in the past,Anholt was covered by pinewood.

The present trend is that the dunes are becom-ing overgrown with woodland, however, prima-rily with imported species. Even in the absenceof the imported tree species, the dunes have beenheavily overgrown since livestock grazingstopped. The grey dune vegetation has, at manylocalities, been replaced by dense crowberryvegetation and there is no doubt that withoutthe impact of livestock grazing, the majority ofthe near-shore dunes would eventually turn intowoodland or copses.

The natural habitat type 'decalcified fixed duneswith Empetrum nigrum' has a calculated criticalload of 10-15 kg nitrogen ha-1 year-1 and thepresent deposition in the near-shore parts ofDenmark is in general 6-15 kg. The lowest lev-els were measured on Anholt and along the coastof northern Zealand. The present level of air-borne ammonium is thus threatening the long-term stability of this type. The interrelation be-tween nitrogen deposition and vegetationalchange is based on observations made in theNetherlands and England (Bobbink et al. 1998).The Danish county authorities have also re-ported the first stages of the invasion of bentgrass and increasing eutrophication at 4 locali-ties where the natural habitat type borders in-tensively cultivated farmland.

Historically, the atmospheric deposition of ni-trogen in these natural habitat types has con-tributed between 2 and 5 kg nitrogen per year.Today it is more commonly between 8 and 15kg nitrogen. In the long run this deposition mayshift the balance in these sensitive plant com-munities towards more nitrogen-loving speciessuch as bent grass and wood reed.

The rising number of tourists particularly in thewestern part of Jutland may break down the rela-tively sensitive nature of this natural habitattype. Although recreational erosion is generallyconsidered to be of minor importance, increas-ing erosion because of growing tourism has beensporadically recorded in recent decades. Erosionis most frequent at the edge of the habitat typeand along the paths to the beach.

At 42% of the reported localities there is cur-rently no grazing and in more than 40% of theareas some level of grazing was reported. At onelocality the grazing was reported as intense. Noscrub encroachment had been recorded at 30%of the localities. Overgrowth by scrub was re-ported as minor to moderate at 52% and heavyat 7% of the localities. Most of the reports men-tion the invasion of woody plants, especiallymountain pine, but also species like dunal pine,European aspen, gorse, Rugusa rose and broomoccur. The reports do not specify whether it isthe low, Danish sub-species of broom or a cross-breed with the French sub-species. Apart fromEuropean aspen and maybe broom these spe-cies are either imported or adventive.

Systematic monitoring of the vegetation onlytakes place at 3 localities. In the grazing areasthere is most likely some sort of regular inspec-tion. This may also be true of areas with pineclearing. Observations here suggest a re-growthof dwarf shrub.

Because of the impact of the increased ammo-nium deposition, the overall assessment of struc-ture and function must be characterised as 'un-certain'.

Typical species

Uniform crowberry heaths occur in many duneareas strongly affected by the wind. Apparently

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crowberry Empetrum nigrum is most successfulin the western part of Jutland, most likely be-cause of its climatic demands (Tybirk et. al. 2000).Carex arenaria is common in sandy and dry ar-eas. Many beach ridges and dry sand bottomsas for example at Sejerø Bay, Rørvig and onUlvshale on Møn are covered by strong anddense heather, Calluna vulgaris, and mosses andlichens.

Woody plants are often represented by self-sownspecies like Pinus mugo, Pinus contorta, Populustremula, Ulex europaeus, Rosa rugosa, and Saro-thammus scoparius. The robust moss speciesPleurozium schreberi and Hypnum cupessiforme areoften observed in between the dwarf shrub. Li-chens as Cladonia arbuscula and C. portentosa mayalso be abundant in between the taller plants.

The invasive species Rugusa rose and mountainpine represent by far the greatest managementproblems. However, a second special problemhas become manifest during the latest nearly 30years: the aggressive moss species, Campylopusintroflexus is spreading like a carpet in manyformer low-level dune areas. On Rømø, Anholtand in the army range at Oksbøl, observationshave been made of this invasive moss formingcarpets over extensive areas. Apart from oust-ing lichens, this species also prevents seed-dis-persing species like heather from settling. In theNetherlands where Campylopus introflexus hasspread since the 1960s it has occupied very largedune areas. In these areas, attempts to restorethe original dune vegetation are being made bypeeling off the moss carpet with machines (S.N.Christensen, pers. comm.).

Quite a few of the localities recorded representmixtures between types 2130 and 2140 withsome mires and fens occurring within the stabi-lised blowing-out areas. These areas may beflooded during the winter and Erica tetralix cantherefore often be observed in large stands (tran-sitional stage to type 4010). In disturbance ar-eas, wind breaches and thus white dunes (type2120) may occur.

Conservation status

The conservation status of the natural habitattype 2140 must be characterised as uncertain

(Table 3.2). The dwarf-shrub-dominated heath-land seems to be stable provided that grazingand the clearing of growth of woody plants arecontinued. The assessment is uncertain, as thelong-term impact of the ammonium depositionon this natural habitat type is unknown. It is alsouncertain whether the natural dynamics can bemaintained at the present level of coastal pro-tection and dune stabilisation, and the pressurefrom non-native invasive species seeds.

3.1.4 2250* Coastal dunes withJuniperus spp.

The type is defined as Juniperus communis (juni-per) formations in coastal dunes. At most locali-ties this vegetation type is associated with greydunes with a dominant vegetation of heatherand bent grass, but it also occurs in green dunes.Occurrences in heaths, dry grasslands and in-land dunes are classified as type 5130.

The vegetation type is found in areas where graz-ing is going on or has been practised in the past.The grazing pressure has in the past been inten-sive and all usable wood has been removed. Thiscommunity has thus appeared as relatively openscrub far from the nearest woodlands. This situ-ation has changed radically for the majority ofthe vegetation types recorded where woodlandsare now close to the natural habitat type at manylocalities.

As this community grows on shifting sand, theecosystem is, as for all near-shore areas, rela-tively young. The soil characteristics of the fixedcoastal dune heathland have been studied inseveral places and in general the soil is less than300 years old. This should be taken into consid-eration when assessing the stability conditions.

Natural range

This natural habitat type is rare and occurs onlysporadically in small areas, most frequently inwestern and northern Jutland, at Sejerø Bay andalong Præstø Fjord. A single record on Rømø hasbeen excluded as only one juniper was observed.The type is reported from 15 localities, totalling336 ha (Fig. 3.1.4). Within the 8 SACs, knowl-

27

edge of the extent of this type seems to be al-most complete. It is also thought that these ar-eas represent the total extent of the Danish re-source of this community.

Structure and function

The long-term maintenance of this natural habi-tat type is considered to be dependent on thegrazing intensity, scrub encroachment, recrea-tional erosion, the extent of disturbance/erosion,and on the atmospheric deposition of nitrogen.

Moderate to heavy shrub encroachment was ob-served at more than 70% of the localities. Apartfrom one locality where the invasion of sea buck-thorn and bushgrass prevents the junipers fromregenerating, the invading plants are primarilytrees such as oak, pine, spruce, and birch.

At reported localities, 70% are being grazed.Grazing is often combined with removal of treesand in three cases clearing of junipers also oc-curs. The community type is difficult to main-tain in the long term. The natural successionaltrend will always be towards climax woodlands.Clearing of scrub may therefore be essential tohalt succession, and in order to support the re-

generation of junipers the maintenance of graz-ing is also crucial. At 70% of the localities treeshave already been or are going to be removedto safeguard the survival of this natural habitattype. Erosion as a result of recreational pressureis considered to be heavy at 20% of the locali-ties.

The National Environmental Research Institutehas calculated the critical load for decalcifiedfixed dunes with Empetrum nigrum (natural habi-tat type 2140) to be between 10 and 15 kg nitro-gen ha-1 year-1 (Tybirk & Jørgensen 1999). As thepresent annual deposition in type 2250 is likelyto be at approximately the same level, there is arisk that the long-term stability of this naturalhabitat type may be threatened by this sourceof environmental change. The growing nutrientload is presumed to inhibit the regeneration ofjunipers, as this species can only sprout in min-eral soil and is sensitive to competition fromdense vegetation in its early phases of growth.From the reports it appears that eutrophicationhas not been studied in detail. One reports re-fers to a general 'homogenisation' of the groundflora and in another report, nearby manure tanksare mentioned as presenting a local risk ofeutrophication.

Typical species

The only species stated in the InterpretationManual to the Habitats Directive is juniperJuniperus communis. This species is present at alllocalities. At four of these, denser juniper standsare considered a management objective, whileat another, there is the potential for great spreadof the species over the habitat available.

In most localities the type is associated with fixeddune heaths with a dominant vegetation ofCalluna vulgaris, Empetrum nigrum and Des-champsia flexuosa but it has also been located ingrey dunes (type 2130) and green dunes. At afew localities species associated with acidic fensand calcareous fens are present.

At one locality specific action has been taken toprotect the red-listed species, barred warblerbreeding in dry south-facing scrub.

Figure 3.1.4. Coastal dunes with Juniperus spp. (2250).Special Areas of Conservation with reported occur-rences of the natural habitat type in Denmark. The sitesare centred in the Special Areas of Conservation. Theboundary between the Atlantic region and the Conti-nental region is shown on the map.

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Conservation status

The conservation status of natural habitat type2250 is assessed to be favourable (Table 3.2), be-cause of the protective action taken. Rather thana decline in this habitat type, the present extentof this community may spread locally (at the costof bordering woodland) as grazing is plannedto be extended to part of the woods in some ar-eas.

The assessment of the national geographicalrange of the community type is certain, as it iseasy to define and map. However, the assess-ment of the conservation status is uncertain, asit is unknown how the long-term nitrogen depo-sition will influence the regeneration of junipers.In quite a few cases the management measureshave included clearing of juniper shrub to fa-cilitate grazing. The results of this managementprocess are unknown and the knowledge nec-essary to evaluate the succession processes inrelation to the conservation status of the type isnot available.

3.1.5 6120* Xeric sand calcareousgrasslands

The type is defined as dry, open grasslands oncalcareous sand characterised by a high propor-tion of annuals in the vegetation and a promi-nent continental flora component. The type isdescribed from southeastern Sweden (Olsson1974) where it is characterised by extremely drycalcareous sandy soil and many rare species.Cultivated grass fields and fallow land are notincluded in the Habitats Directive.

In Denmark, this community type is knownfrom both previous and recent studies of grass-lands (Bruun & Ejrnæs in press). These studiesshow that the Danish grassland vegetation ismainly characterised by dry grasslands hostinga vegetation composition primarily determinedby a dry microclimate resulting from a south-facing exposure combined with a dry and warmlocal climate. These dry grasslands can be di-vided into 3 types, one type occurring on richcalcareous moraine formations, and two typesoccurring on sandy soils. The sandy-soil typescan be considered as type 6120 if the sand is cal-

careous whereas the moraine type can be con-sidered as type 6210. A definite distinction be-tween the widely defined semi-natural drygrassland and scrubland facies on calcareoussubstrates (6210) and the narrowly defined Xericsand calcareous grasslands (6120) requires an in-depth knowledge of the variety of Danish grass-land vegetation.

Type 6120 mostly occurs on steep south-facingslopes along existing and former coastlines andin undulating moraine formations. The type isalso known from beach ridges and calcareousdunes but is here classed with other natural habi-tat types occurring on beach ridges and in dunes.The type has a relict character serving as an im-portant habitat for a wide range of rare, nativespecies, e.g. Potentilla cinerea, Petrohargia prolifera,Medicago minima, Scabiosa canescens, Carexligerica, Pulsatilla pratensis, Veronica verna, andFestuca polesica. The vegetation type also hosts aseries of rare warmth-loving invertebrates.

Natural range

The community type is exclusively known inDenmark east and north of the line defining theextent of ice cover during the last ice age. Itsmain occurrence is in the Great Belt area but theliterature also refers to significant occurrenceson Møn, in northern Zealand around Isefjorden,on Bornholm (Hammeren and Boderne) and inHimmerland (Ejrnæs 1998). The biotopes areoften small areas of slope characterised by thecombination of calcareous sand and south-fac-ing exposure.

Altogether 31 sites of this type have been re-ported. Twenty-nine examples of this commu-nity are distributed between 14 SACs. The re-maining 2 examples are recorded from Stege Norjust outside habitat area 179. The remaining habi-tats are small, typically between 0.5 and 2 ha.

The community type is, in all probability, alsopresent in several localities in SAC 47 in thesouthern part of Helgenæs (R. Ejrnæs, unpubl.data) and on a south-facing slope at Tissø in SAC138 (Bruun 1997). The occurrence of type 6210has been reported from Helgenæs and Tissø andit is likely that both types (6120 and 6210) occurat the localities. The type was previously known

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from Hammeren in habitat area 160 and Samsø(Møgelskår and the northern east coast) in SAC182. The type was possibly also previously oc-curring on Melby Overdrev (SAC 119), at Dybesø(134), at Korshage (148), at Stejlbanke south ofVester Egesborg (148), and at Lild dune planta-tion (185). It remains to be checked whether thetype occurs on Nekselø and at Sanddobberne(135).

A review of the reported species lists suggeststhat in 5 out of the 31 occurrences the presenceof type 6120 can be substantiated. (Røsnæs,Ristinge Cliff, Høvblege, Møns Cliff and Jydele-jet). The type may be represented in 16 sites anda further 10 occurrences should rather be classi-fied as being either 6210 or 6230. The followingreview of this community type will be based onthe 21 (5+16) that are most likely to be repre-sentative of this type (Fig. 3.1.5). The digitisationof this community type has been carried outbased on various sources of information andshould therefore not be considered an appropri-ate measure of the true extent of the commu-nity. However, an estimate suggests that the ex-tent of the community reported, includingpoorly documented sites is approximately 33 ha.

Structure and function

The combination of an extremely dry micro-climate, calcareous, nutrient-poor soils and a

strong gradient means that this type is very re-sistant to scrub encroachment. Stress caused bydrought, lack of nutrients, and erosion make itdifficult for woody plants to gain a foothold inthe vegetation. Nevertheless, the type can be-come overgrown with woody plants (sloe, haw-thorn, roses, and spindle tree) and extensivegrazing with browsing of woody plants is con-sidered to be an important factor for the long-term maintenance of this natural habitat type.The relative function of winter grazing versussummer grazing is unknown.

In coastal areas, extensive grazing areas havebeen converted into coniferous plantations andrecreational summer cottage areas during the20th century, a fact that has added to the threatof scrub encroachment. At many localities inva-sive species like Rugusa rose, Scots pine, andmountain pine are colonising dry sandy areasand these species must be regarded as a threatto the type, both directly and indirectly, in mak-ing the local climate milder and preventing thecrucial erosion processes.

In 15 sites, scrub encroachment is stated to be aproblem, in 6 occurrences the pressure exercisedby the public is indicated to be a potential prob-lem and in 5 occurrences eutrophication is statedto present a potential problem. In one occur-rence, sludge was spread in 1999. The impact isnot yet known but an estimate suggests thatsludge application is irreconcilable with a long-term conservation of the natural habitat type.

Typical species

The Interpretation Manual (Skov- og Natursty-relsen 1999a) on natural habitat types specifies16 typical species, among which 9 species areknown in Denmark: Allium schoenoprasum,Cardaminopsis arenosa, Carex ligerica, Dianthusdeltoides, Helichrysum arenarium, Herniaria glabra,Koeleria glauca, Petrorhagia prolifera and Sedumreflexum. Apart from Dianthus deltoides, Helichry-sum arenarium, and Herniaria glabra these spe-cies are rare. Additionally, more of the speciesspecified are not particularly good indicators ofthe natural habitat type in Denmark as they arejust as abundant or even more abundant in othernatural habitat types. This is applicable to Koe-leria glauca, especially occurring in dunes, Heli-

Figure 3.1.5. Xeric sand calcareous grasslands (6120).Reported occurrences of the natural habitat type inDenmark. The boundary between the Atlantic regionand the Continental region is shown on the map.

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chrysum arenarium, Herniaria glabra and Dianthusdeltoides, which specifically occur on dry lime-deficient sand soils, and Allium schenoprasumwhich occurs on beach rocks on Bornholm. Man-y populations of Allium schenoprasum and Sedumreflexum are thought to have originated from in-troductions from cultivated areas. Remainingspecies such as Petrorhagia prolifera and Carexligerica are specifically associated with dry, sandyslopes.

To further assist in mapping the true extent ofthis community, the Danish Forest and NatureAgency has (in collaboration with NERI) andwith reference to CORINE (Corine BiotopesManual 1992) prepared a supplementary list ofspecies characteristic of this type in Denmark.This list includes Cerastium semidecandrum, Vicialathyroides, Phleum arenarium, Aira caryophyllea,Trifolium striatum, Erophila verna, Myosotis stricta,Silene conica, S. otites, and Festuca polesica. Sev-eral of these species also occur in other ordinaryhabitats, e.g. sandy fallow lands, although thisdoes not qualify for a classification in this natu-ral habitat type.

From Røsnæs one occurrence where the type iswell documented has been recorded. The spe-cies specified from this locality are Silene conica,Trifolium striatum, Aira caryophyllea, Cerastiumsemidecandrum, Dianthus deltoides, Helichrysumarenarium, and Phleum arenarium. Several reportsdo include annuals typical of the natural habi-tat type (e.g. Cerastium semidecandrum and Heli-chrysum arenarium). Perennial species character-istic of south-facing slopes (e.g. Phleum phleoidesand Artemisia campestris) have also been identi-fied. Many of these reports also include speciessuch as Briza media, Plantago media, Poa compressa,Viola hirta, Centaurea scabiosa, Potentilla reptans,and Agrimonia eupatoria. It is, however, assessedthat these should rather be classed with the morebroadly defined natural habitat type 6210. Quitea few reports include species such as Rumex ace-tosa, Calluna vulgaris and Agrostis tenuis, speciessuggesting the occurrence of the equally broadlydefined grassland type 6230 occupying lime-de-ficient soil.

An assessment of whether occurrences with awell-developed vegetation of the species typi-cal of natural habitat type 6120 are likely to be

found within the SACs would require a moredetailed survey.

Conservation status

The conservation status of natural habitat type6120 must be characterised as uncertain (Table3.2). The community type is particularly com-mon on steep slopes where extensive grazinghas stopped. Based on reports received, the veg-etation type is considered to be decreasing as aconsequence of scrub encroachment and thistrend is thought to be generally representativeof what is happening to the community typethroughout Denmark. On the other hand, scrubencroachment is likely to proceed only slowlybecause of the microclimate and the nutrient-poor soil that characterises the habitat, and inmost sites there is the potential to reverse thetrend by reintroducing extensive grazing. Re-introduction of grazing is, however, complicatedby the fact that it is difficult to fence the areas,that they provide poor-quality grazing, and thatthey are often isolated in the neighbourhood ofprivate summer cottage areas.

3.1.6 6210 Semi-natural dry grass-lands and scrubland facies oncalcareous substrates (Festuco-Brometalia) (*important orchidsites)

Description

The semi-natural habitat type 6210 is defined asgrasslands and scrubland on calcareous to neu-tral substrates. The vegetation type is consid-ered a priority type if it is an important orchidsite, which means habitats hosting many orchidspecies, at least one red-listed orchid species oran important population of a less common or-chid species. Grass fields and fallow lands arenot included in the Habitats Directive.

This vegetation type is very broadly defined andincludes most of what in Denmark is defined ascalcareous grasslands (Bruun & Ejrnæs in press).

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The vegetation comprises calcicole plants grow-ing on several different soil types, on flat ground,but also on slopes with varying sun exposure.Exceptions are communities and localities ingreen dunes that are classified as type 2130 andthose localities on very dry calcareous sand thatfall within type 6120. In areas where the calcar-eous content has been wholly or partiallywashed out (pH 6-7) the community type repre-sents a transitional stage towards type 6230; insuch cases, the species composition will deter-mine the appropriate classification. In freshbeach ridge hollows and at the edge of calcare-ous fens this community type may be in transi-tion towards type 7230. In clearings in wood-lands there may be a gradual transition into sev-eral different forest types. Areas of dry scrub (e.g.hawthorn, rose, sloe, hazel, spindle tree, apple,elder, dog-berry and other species) are consid-ered to belong to this type if they represent in-vasion stages of dry grassland vegetation.

The type is prevalent on calcareous moraineslopes along extant and former coastlines, inriver valleys, and in lateral moraine formations.The important orchid sites are most abundantin association with the calcareous soils on Møn,central Zealand, and in Himmerland.

Natural range

The type is almost exclusively found north andeast of the limit to glacial cover where it occursin most undulating landscapes. The communityis now rare and has declined tremendously be-cause of cultivation, planting, fertilisation andscrubbing over of dry grasslands throughout thelast 200 years. This decline is illustrated by thedecline in the characteristic species, Dark-winged Orchid, which used to be known fromabout 50 localities, especially on Zealand, Funenand Bornholm but is now only known to occurat two localities in Jutland (Ejrnæs et al. 1998).

In all, 38 sites of the type have been recorded,all located within or partially within the SACs.Ten localities were originally recorded as type6120 but these have been revised and are nowclassified as type 6210. Twenty-two localities areassessed to be priority natural habitat types onthe basis that they host important populationsof one or more orchid species. These 22 priority

habitats are distributed between 9 SACs (Fig.3.1.6). The extent of these habitats varies from0.2 ha to approx. 30 ha. However, the extent ofthe habitat has been digitised on the basis of dif-ferent information sources and is thus not ap-propriate for an accurate account of the total areaof coverage. However, based on anecdotal ac-counts and a rough assessment of the materialrelating to several key species, it is estimated thatthere is approx. 284 ha of this community typein Denmark. The 16 non-priority sites are con-sidered to represent a small random selection ofthe community types already well representedin the SACs and so these are not considered fur-ther here.

It is thought that the current mapping of 6210*(with orchids) does not fully cover the occur-rence of the type within the SACs. The type isknown to occur in SAC 20 where two nationallysignificant orchid species, Dark-winged Orchidand Lady’s Slippers Orchid are known to occur.

Structure and function

The habitat type 6210 is a semi-natural type, i.e.the maintenance of the type is dependent ongrazing or mowing to halt the succession to-wards woodland. On very dry or very calcare-ous slopes, scrub invasion proceeds very slowlyand certain species have been suggested as post-

Figure 3.1.6. Semi-natural dry grasslands and scrub-land facies on calcareous substrates (6210). Reportedoccurrences of the semi-natural habitat type in Den-mark. The boundary between the Atlantic region andthe Continental region is shown on the map.

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glacial relicts, for example Polygala amarella, Dra-ba incana, Cineraria integrifolia, Prunella grandi-flora, Pulmonaria angustifolia (Bruun & Ejrnæs1998). The type is often found on potentially fer-tile, naturally oligotrophic to mesotrophic soilsand has therefore been exposed to fertilisationand cultivation for a long time. Fertilisation andcultivation cause irreversible changes to thiscommunity. The habitat type is also consideredto be sensitive to dry and wet deposition of air-borne nitrogen compounds that may acceleratethe scrub development and shift the vegetationtowards tall competitive species. Supplementaryfeeding of livestock on the sites may lead toeutrophication.

The general trend of deterioration in the habitattype is illustrated by recent repeated studies in1989 of slopes where the vegetation was mappedby Böcher and Fredskild in 1940 and 1951 (Feil-berg 1990). This study proved that the vegeta-tion on gentle slopes originally supportingclosed herbaceous vegetation had changed sig-nificantly. One third of the slopes were com-pletely overgrown with woody plants, many ofthe other slopes had been invaded by tallmeadow oat. Most slopes exhibited an unmis-takable decline in species associated with nutri-ent-poor soils and the invasion of typical farm-land species was frequently observed.

Even though the habitat type is dependent upongrazing for its continuation, it is not possible todefine the optimum successional stage andhence stocking density in practise. Some speciesare associated with tall-growing vegetation, oth-ers are associated with wood fringes and gaps,e.g. Cypripedium calceolus, Orchis insectifera,Orchis mascula, Dianthus armeria, Trifoliumalpestre, Inula conyza, Melampyrum cristatum,Vincetoxium herundinaria, Satureja vulgare. Thiscommunity type has almost disappeared fromthe landscape following the cessation of graz-ing in the woods as a result of the Forest Preser-vation Regulation, after which the borders be-tween wood fringes and the open agriculturallandscape became sharply delimited. Other spe-cies are more typical of open grassland with bothtall and short vegetation, e.g. Gentianella spp.,Carex montana, Polygala spp., Potentilla spp., Inulaspp., Petrohargia prolifera, Orchis ustulata. In smallhabitat units it can be difficult to strike a bal-ance in grazing intensity that avoid both scrub

invasion and overgrazing. It is important to notethat scrub also occurs in this type, although suchconditions are rarely conducive to the presenceof orchid species.

Special conditions apply to the orchids typicalof 6210*. The reproductive strategy of the orchidsis characterised by their abundant productionof small seeds, which provide an enormous ca-pacity for dispersal but carries the cost of verylimited competitive ability in the juvenile phase.Hence, the critical factor in the long-term main-tenance of a population is not just seed produc-tion but relates to their chance of becoming es-tablished. Livestock grazing, the behaviour ofanimals and other sources of disturbance aretherefore very important.

Scrub encroachment is the most frequently (16sites) documented cause of change at the 22 type6210* sites. Of 16 sites currently being over-grown, 12 localities are presently grazed but itis uncertain whether this management measureis sufficient to counteract further scrub invasion.At 5 sites scrub invasion is considered to be anacute threat, and eutrophication threatens 3other sites.

Typical species

The community type is characterised by a widevariety of species, which in Denmark are: An-thyllis vulneraria, Arabis hirsuta, Brachypodiumpinnatum, Bromus inermis, Campanula glomerata,Carex caryophyllea, Carlina vulgaris, Centaurea sca-biosa, Koeleria pyramidata, Leontodon hispidus, Me-dicago sativa spp. falcata. Orchis insectifera, Orchismascula, Orchis morio, Orchis purpurea, Orchisustulata, Primula veris, Sanguisorba minor, Scabiosacolumbaria, Bromus erectus, and Silene otites.

There is also a number of more common speciesthat are good indicators of calcareous dry grass-lands. The species can be grouped in species re-flecting old, unfertilised dry grasslands, e.g.Linum catharticum, Viola hirta, Cirsium acaule,Briza media, Thymus spp. and Filipendula vulgarisand species that are good indicators of a highsoil pH, e.g. Carex flacca, Dactylis glomerata,Prunella vulgaris, Plantago media and Medicagolupulina. The range of species present reflects thefact that this community type occurs on both

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humid north-facing slopes and on dry south-facing slopes.

In the reports received relating to this habitattype, the vegetation present shows a representa-tive selection of the typical species. Amongstthese are the following orchid species: Orchismascula, Orchis morio, Dactylorhiza fuchsii, Platan-thera chlorantha, Orchis purpurea, Cepalanthera da-masonium, Listera ovata, Epipaetis atrorubens, Ama-camptis pyramidalis, Cephalanthera rubra, Her-minium monarchis, Cypripedium calceolus, and Or-chis ustulata. However, the species lists reflectthat they originate from different plant commu-nities and it is estimated that some of the spe-cies rather occur in bordering forest or miretypes.

The populations of species such as Orchis ustu-lata, Cypripedium calceolus, and Amacamptis pyra-midalis are so small and isolated that their conser-vation status can not be assessed as favourable.The same is true for species considered to beextinct, such as Coeloglossum viride and Spiranthesspiralis. Orchis ustulata previously occurred inmany different habitats, and it is considered thatthis species in particular has the potential toexpand given the appropriate management andrestoration of conditions within its habitat niche.

Conservation status

The conservation status of 6210* must be as-sessed as uncertain (Table 3.2). It is essential thatmany of the important recent orchid sites aresubject to some kind of management and moni-toring activities and this, to a large extent, is thecase within the SACs. Despite these measures,many sites are becoming overgrown and manyorchid populations are so small that their long-term survival is uncertain. Airborne nitrogendeposition is a potential threat, but the extent ofthis problem has not been studied.

The less well-documented community type 6210sites without orchids are currently undergoinga dramatic decline because of lack of adequategrazing and eutrophication, and as many ofthese sites are potential orchid sites, the declinecontributes to the negative prognosis for 6210*.

3.1.7 6230* Species-rich Nardusgrasslands, on siliceoussubstrates in mountain areas(and submountain areas, inContinental Europe)

Description

Type 6230 is defined as semi-natural grasslandson decalcified substrates. A prior condition forthis definition is that the vegetation has not beensubject to fertilisation or cultivation. The type ishighly varied, characterised by species such asNardus stricta, Deschampsia flexuosa, Agrostiscapillaris/Festuca ovina and Carex arenaria. Nardusstricta is thus not a strict prerequisite to qualifyfor type 6230. Nardus stricta is a hydrophyte pre-ferring the precipitation-rich areas of the coun-try and spring fed areas in dry grasslands (e.g.on cool slopes) or areas where the ground-wa-ter level is high (e.g. hollows on raised marinedeposits). Therefore, only a small fraction ofDanish acidic dry grasslands will be character-ised by Nardus stricta. The title of the type andthe typical species specified in the Interpreta-tion Manual suggest a narrow sub-type of veryacidic dry grasslands thus creating some diffi-culty in precisely defining the type. The habitattype includes scrub vegetation but not reallydominating dwarf-scrub vegetation. Calluna vul-garis, Vaccinium myrtillus, and V. vitis-idaea oc-cur sporadically in the herbaceous vegetation.Species-poor sites, e.g. grassland heaths withbent grass (Deschampsia flexuosa) and a few com-panion species are excluded.

The type represents Denmark’s most commonsemi-natural grassland type (Bruun & Ejrnæs1998). It occurs on many different types ofground and soils both inland and along thecoasts. In fixed dunes a vegetation type floristi-cally identical to this type also occurs but herethe vegetation is classified as type 2130, fixeddunes with herbaceous vegetation. Like theother semi-natural grassland types, type 6230 isparticularly typical of marginal soil types, onslopes not suitable for cultivation or at localitieswith large stones.

The richest sites are often associated with either

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moist areas or dry, warm areas. In such areasleaching, acidification and formation of a crudehumus layer are presumably limited by the in-put of mineral-rich ground water or by the highevaporation. In wet habitats with spring lines(slopes) or a high ground-water level (hallowson marine forelands) rare species occur, e.g. Ar-nica montana, Platanthera spp., Gentianella cam-pestris, Leucorchis albida, Botrychium, Dactylorhizasambucina, but also more common species suchas Lathyrus linifolius, Succisa pratensis, Hypericumpulchrum, Rhinantus minor and Ranunculus ocrisoccur. In warm, dry habitats species such as Hy-pochoeris maculata, Anthericum liliago, Pulsatillavulgaris, Potentilla spp., Dianthus superbus,Festuca ovina, Silene nutans, Dianthus deltoides andTaraxacum spp. occur.

The richest sites are typically characterised by afloral element from calcareous grasslands suchas Leontodon hispidus, Perimula veris,Leucanthemum vulgare, Briza (wet type), Avenulapratensis, Thymus pulegioides and Filipendula vul-garis (dry type).

Natural range

The type is widely distributed in Denmark oc-curring on both sides of the line defining themaximum extent of ice cover. However, the habi-tat type has become relatively rare and has beendeclining considerably throughout the last 200years because of cultivation, planting, fertilisa-tion and overgrowth of dry grasslands. Thisdecline can be illustrated by the declines in dis-tribution and abundance of the orchid speciesLeucorchis albida and Dactylorhiza sambucina, spe-cies formerly abundant but which are now onlyknown from very few localities (Ejrnæs et al.1998).

Type 6230 is recorded from 35 sites totalling anarea of approx. 245 ha, distributed over 16 SACs.Another 2 sites of approx. 8 ha (Fig. 3.1.7) havebeen recorded. Based on the species list five lo-calities recorded as type 6210 or 6120 have beenclassified as 6230. Based on a scientific reviewof the Danish grassland vegetation (Bruun &Ejrnæs in press) the community type also oc-curs in the SACs 13, 16, 20, 25, 47, 127, 134, 163,184, 185. However, the habitat type has not beenreported from the counties of Viborg and North-

ern Jutland where it is supposed to be quite com-mon. Hence, the current status only includes asmall to moderate proportion of the total occur-rence in the SACs. The present geographicalabundance and range of this community typein Denmark is therefore still very incomplete.

Structure and function

Type 6230 is a semi-natural habitat type and itsmaintenance is conditional on retention of graz-ing or mowing to halt the succession towardswoodland. The majority of this habitat typeoriginates from clearing of wood and subsequentgrazing and the long established continuity asan open community is a prior condition for thedevelopment of the characteristic vegetation.Many of the species characteristic of this habi-tat type have a wide ecological amplitude andalso occur in light open forest situations. Somespecies are, however, also closely associated withcompletely open and light conditions. It is notknown to what extent light, open, calcium poorconditions prevailed prior to the Stone Age inthe Danish landscape. Most probably such ar-eas may have existed on slopes and marine fore-lands associated with natural erosion (land-slides, water and wind erosion). Grazing live-stock or mowing are nowadays factors impera-tive to ensure the long-term conservation of thistype in most areas. The type is associated with

Figure 3.1.7. Species-rich Nardus grasslands, on sili-ceous substrates (6230). Reported occurrences of thenatural habitat type in Denmark. The boundary be-tween the Atlantic region and the Continental regionis shown on the map.

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oligotrophic soils and may be destroyed byeutrophication.

From the reports it appears that scrub invasionis considered to be the most important negativefactor for a long-term conservation of this habi-tat type. Of the reported sites, 17 (representinga total of 150 ha, half of the localities and half ofthe area) are exposed to encroachment by woodyplants. In 10 sites, scrub invasion is character-ised as an acute threat. The majority of these sitesare, however, managed by grazing or mowingand presumably this management will, in thelong term, stabilise the present state. It is, how-ever, estimated that the recorded loss to scrubof 50% is not representative of the status of thetype as it is expected that the majority of theregistered sites are well-known localities alreadysubject to some level of management and moni-toring measures.

Eutrophication is only reported to be a threat atthree localities. At two of these, the threat is dueto adjacent cormorant colonies. However, it ap-pears that the eutrophication risk is purely basedon local opinion and it should be noted that incontrast to scrub invasion, the effects of eutroph-ication are very difficult to observe by inspec-tion or monitoring.

Typical species

The Interpretation Manual specifies a range oftypical species, of which the following occur inDenmark: Antennaria dioica, Arnica montana,Carex ericetorum, C. pallescens, C. panicea, Festucaovina, Galium saxatile, Gentiana pneumonanthe,Hypericum maculatum, Hypochoeris maculata,Lathyrus montanus, Leucorchis albida, Nardusstricta, Pedicularis sylvatica, Plathantera bifolia,Polygala vulgaris, Potentilla erecta, Veronicaofficinalis and Viola canina. A number of the spe-cies specified are good indicators of a long con-tinuity of management and unfertilised condi-tions on Danish grasslands. The narrow speciesselection specified in the Interpretation Manualis not adequate for the wide variety of speciesin Denmark and with reference to CORINE(Corine Biotopes Manual 1992) the following

common species can also be considered indica-tive of the habitat type here: Carex pilulifera, Des-champsia flexuosa, Danthonia decumbens, Antho-xanthum odoratum, Festuca rubra, Agrostiscapillaris, Poa angustifolia, and Calamagrostisepigejos.

To the extent verifiable by a species list, the re-corded localities for this community type havea first-rate representation of typical species.Nevertheless, there is evidence of a very strongdecline in a wide range of typical species dur-ing the last 50 – 100 years (e.g. Hypochoerismaculata, Plathantera bifolia, Leucorchis albida andArnica montana). For the most rare typical spe-cies or red-listed species occurring in this habi-tat type, the status is considered to be critical ifa further population decline (through scrub en-croachment or fertilisation) is not avoided. Thatapplies to species such as Leucorchis albida,Dactylorhiza sambucina, Gentianella campestris,Botrychium simplex and Anthericum liliago. Orchisspp., Botrychium spp. and Gentianella spp. arepoor competitors in their juvenile phase andamongst the Gentianella spp., the short-livedseedbank further restricts its ability to persistamongst aggressive competitive species. It isuncertain whether the regeneration abilities ofthese species are today being adequately con-sidered in the management of their habitats.

Conservation status

The conservation status of 6230 is considered un-favourable (Table 3.2). Extensive scrub encroach-ment, lack of knowledge of the natural range ofthe community type and lack of representationin the SACs contribute to the negative assess-ment. Small isolated populations of typical spe-cies are supposed to be exposed to continuouslocal extinction as a consequence of the declinein the natural habitat type during the latest 200years. However, on a positive note, it should beemphasised that the decline is being checked asa result of Section 3 of the Protection of NatureAct, which provides general protection againstfurther cultivation and fertilisation. However,how effective these measures have been inachieving a slow-down can not be verified.

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3.1.8 7110* Active raised bogs

Description

Type 7110, active raised bogs, is characterisedby so much peat formation over a sufficientnumber of centuries that the bog typically re-ceives only atmospheric water as recharge (om-botrophic water saturation). The raised bog istherefore lime-deficient, acidic and extremelypoor in nutrients. The peat is primarily formedby the characteristic raised-bog mosses Spagnumcuspidatum, S. rubellum and S. magellanicum.

The term 'active raised bog' refers to the fact thatan active peat formation of the raised bog mustbe ongoing. Raised bogs, which for natural rea-sons might be temporarily not growing, for rea-sons such as a period of drought, are also in-cluded. To support the conservation of thisunique ecosystem over its geographic range,areas of a lower 'quality', e.g. partially degradedraised bogs are also included and should, wherepracticable, be regenerated. (Anon. 1996).

Only a few species of vascular plants and mossescan survive in this extremely nutrient-poor,acidic and wet environment. The natural habi-tat type is dominated by sphagnum mosses.

The Danish monitoring of raised bogs has fo-cused on the surface relief of the raised bog(Risager & Aaby 1996, Risager & Aaby 1997,

Risager 1999) but apart from the raised bog sur-face it also includes the margin bog zone andthe lagg, being a wet zone around the raised bog.

In cases where heavy drainage, peat digging,eutrophication and the early stages of immigra-tion of species atypical of raised bogs have modi-fied this community, the habitat type is classi-fied as 7120, degraded raised bogs with the po-tential for regeneration. Danish experts on ac-tive raised bogs are of the opinion that bogwoodlands do not naturally occur in Denmark(M. Risager, pers. comm. 2000). Drained, dug-out and eutrophic raised bogs which are nowcovered by wood should be considered a cul-tural modification of this habitat type, not com-parable with the naturally occurring bog wood-lands in, for example, the Baltic countries.

Natural range

This natural habitat type was common in thepast, but nowadays it is rare in Denmark andalmost everywhere threatened by drainage andeutrophication-related overgrowth (Risager &Aaby 1996, Risager & Aaby 1997).

The southern part of Lille Vildmose, Tofte Mose,is the biggest active raised bog in Denmark andone of the largest in the European lowlands. Thearea of about 2,000 ha represents approx. 2/3 ofthe totally reported area.

In two other large active raised bogs Store Vild-mose and Homegårds Mose minor parts are stillassessed to qualify for the definition active raisedbog even if the major part has been disruptedby drainage. Data from 17 bog areas have beenreported and the raised bogs in Lille Vildmose,Store Vildmose and Draved Mose have beendivided and recorded on several forms. Alto-gether data from 22 raised bog areas totalling3,375 ha distributed over 12 SACs have beenreported (Fig. 3.1.8). Møllelung Mose andStenholt Mose have been reported, but they arelocated outside SACs. Stenholt Mose, which isthe third-largest bog area, is considered to behighly worthy of conservation (M. Risager, pers.comm. 2000).

In total, 22 raised bog areas are included in thenational programme monitoring Danish raised

Figure 3.1.8. Active raised bogs (7110). Reported oc-currences of the natural habitat type in Denmark. Theboundary between the Atlantic region and the Conti-nental region is shown on the map.

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bogs (Risager & Aaby 1996, Risager & Aaby1997). Data from almost half of these areas havenot been received. Three of those monitored, butnot reported active raised bogs occur in SACs,e.g. Tvilling Mose, Hatten and Langkær Mose(from SACs 41, 41, and 49, respectively).Letmosen is located just outside SAC 41. Theremaining four raised bogs covered by the moni-toring programme and which still contain rem-nants of active raised bog (Bølling Mose, SvaneMose, Abkær Mose, and Brandstrup) are locatedoutside the SACs. Four of the reported localities(the raised bogs in Langbjerg Plantation, NyboMose, Storelung, and Horreby Lung) no longerqualify for the category 'active raised bog' butshould be categorised as type 7120 (M. Risager,pers. comm.). The reported information is thusnot representative of this habitat as a whole inDenmark.

The reported data only provides restricted back-ground data for the assessment of whether thenatural habitat type has a stable range or is de-clining. Based on the data reported, primarilyincluding information on structure, it is esti-mated that the area of mire at one locality is in-creasing, one is stable, 8 are declining, and thestatus of 12 localities can not be assessed.

Structure and function

Several of the recorded raised bogs have a verylong history dating back several thousands ofyears. Their history is documented by analysesof several metres of thick peat layers. However,this unique, long-continuity ecosystem has beenseriously damaged during the last 200 yearsowing to drainage, peat digging, and cultiva-tion. In addition, this extremely nutrient-poorhabitat type is threatened by nitrogen deposi-tion, which has doubled since the 1950s (Risager1999). The impact of drainage and nitrogen re-spectively is difficult to distinguish, as the drain-age will also result in eutrophication because ofthe increased mineralisation of the substrate.Finally, the integrity of this habitat type may alsobe damaged by intensified agricultural activity,including vehicular access and grazing.

The decline in Cladonia portentosa on monitoredraised bog areas has, however, been taken as anindication of the negative effects of nitrogen

deposition rather than drainage (Risager & Aaby1996). The fact that eutrophication is heavilyinfluencing the natural habitat type and the veg-etation composition has been known for a longtime and was described at the beginning of thelast century (Petersen 1917). Nitrogen deposi-tion can affect vegetation composition in differ-ent ways, for instance by favouring dwarfbushes and trees, which will out-shadow herbsand mosses. Increased nitrogen absorption canprobably affect the frost resistance of some spe-cies, thus modifying competitive interactionsbetween species. There is, however, no doubtthat both eutrophication and drainage have anegative impact on the raised bogs leading tofurther desiccation and scrub encroachment.

The reports show that the majority (18) of thelocalities are subject to different monitoringmethods. In total, 7 different monitoring meth-ods with 5 different intensity levels have beenreported.

Five localities are reported to have become drier,6 are reported to be affected by eutrophicationand 15 are subject to scrub encroachment. In 5sites, sporting interests (digging of waterholesfor ducks, unnaturally large populations of wildboars and red deer, pheasant re-stocking, fol-lowed by dumping of gizzard stones) are re-ported to have a negative impact on the naturalhabitat type. On this basis, the condition of the15 localities is considered to be of unfavourablestatus.

Typical species

The raised bogs are extremely poor in vascularplant species and none of these are exclusive tothis natural habitat type. Thus the vegetation ofthe raised bog can not be exclusively definedbased on vascular plants, and it is essential toalso include the sphagnum mosses. The typicalvascular plants specified in the InterpretationManual are: Andromeda polifolia, Drosera rotun-difolia, D. anglica, D. intermedia, Eriophorum vagi-natum, E. gracile, Oxycoccus palustris, Calluna vul-garis, Empetrum, nigrum, Carex limosa, C. pauci-flora, Rhynchospora alba, R. fusca, Scheuchzeria pa-lustris, Utricularia intermedia, U. minor, U. ochro-leuca. Other typical species are Sphagnum magel-lanicum, S. angustifolium, S. imbricatum, S. fuscum,

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S. balticum, S. majus, Odontoscisma sphagni, andCladonia spp.

The vegetation of raised bogs in Denmark hasbeen extensively researched and monitored anda species list more adequately covering the Dan-ish species has been produced (Risager & Aaby1996, Risager 1999). Basic species mentioned are:Calluna vulgaris, Erica tetralix, Empetrum nigrum,Andromeda polifolia, Oxycoccus palustris, Eriopho-rum angustifolium, Eriophorum vaginatum, Tricho-phorum caespitosum, Rhynchospora alba, Droserarotundifolia, D. anglica, D. intermedia, and Rubuschamaemorus. Twelve sphagnum mosses havebeen identified as being typical native speciesof Danish raised bogs: Sphagnum magellanicum,S. tenellum, S. compactum, S. cuspidatum, S. rubel-lum, S. capillifolium, S. fuscum, S. papillosum, S.molle, S. angustifolium, S. imbricatum spp. austinii,and S. subtines. It should be noticed that thereare essential differences between this speciesselection and the selection specified in the In-terpretation Manual, differences that can not allbe explained by the fact that the manual includesthe margin and lagg zones.

Based on the existing research and monitoringprogramme in Denmark it is also possible to listsome indicator species known to appear in theraised bog vegetation when the natural habitatis subject to undesirable change. These speciesare: Dryopteris carthusiana, Carex nigra (note thatthe latter species is specifically listed as a typi-cal raised bog species in the InterpretationManual), Molinia coerulea, Deschampsia flexuosum,Vaccinium uligonosum Chamaenerion angustifoli-um, Picea abies, Vaccinium vitis-idaea, Sphagnumfallax, S. palustre and S. fimbriatum.

Raised bog vegetation is the only Danish natu-ral habitat type not hosting any grass species.However, Molinia coerulea, has been recorded inhalf of the habitats suggesting that unnaturalconditions prevail on these raised bogs.

The general impression from the species datareported does not enable an assessment of thequantitative and qualitative occurrence of thespecies over time. The data reported on typicalspecies vary enormously between sites. At fivelocalities, a species list (including Menha aquatica,Epilobium palustre, Phalaris arundinacea, andMysotis palustris) proves that the species list was

compiled from habitats beyond the boundariesof the true raised bog habitat type. Five reportsdo not distinguish between the various Sphag-num species. It is, however crucial to distinguishbetween the species to be able to follow the de-velopment of the hummock-hollow structure,thus enabling an assessment of the conservationstatus of the raised bog.

Where monitoring data are available, they havebeen included in the general assessment, how-ever, with the proviso that the available vegeta-tion data are primarily derived from the activepart of the raised bog surface. It is consideredthat the conservation status of the typical spe-cies is unfavourable at 5 locations, that the spe-cies are well represented at 10 sites and that theconservation status remains unknown at 7 sites.

An adequate Danish species list can not be com-piled for the lagg (floristically very closely re-lated to extremely poor fen) and the margin bogzones.

Conservation status

The national conservation status of natural habi-tat type 7110 is considered to be unfavourable(Table 3.2). The assessment is considered to bereliable as more than half of the habitats are in-cluded in some sort of monitoring. More than90% of the 22 reported localities are assessed tohave an unfavourable conservation status. Thisassessment is primarily based on the relativelyhigh number of raised bogs facing problemswith drainage and eutrophication-relatedchanges in vegetation. Also sport-hunting inter-ests are mentioned as influencing some raisedbogs unfavourably.

Monitoring data (Risager & Aaby 1996, Risager& Aaby 1997) support this conservation statusassessment. In the period from 1987/1989 to1995/1996 the hummock vegetation on theraised bogs has generally been increasing.Changes in vegetation composition, includinginvasion of scrub, is not thought to be exclusivelydue to desiccation but it is probably also causedby increases in atmospheric nitrogen deposition(Risager & Aaby 1997).

It should be noted that the monitoring has pri-

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marily focused on the raised bog surface andthat the knowledge of species and processes inthe lagg and margin zones is deficient.

3.1.9 7210* Calcareous fens withCladium mariscus and speciesof the Caricion davallianae1

Description

Type 7210 is defined as vegetation on wet toflooded soil dominated by or with a consider-able component of saw grass, Cladium mariscus.It mostly occurs as dense beds along the fringesof lakes and mires but may also occur as a suc-cession stage of fens and wet meadows. The typeprimarily occurs on calcareous soils and oftenin association with alkaline fens, but it may ex-ceptionally also develop on lime-deficient soils.Areas supporting other fen and reed-bed veg-etation found in combination with Cladiummariscus vegetation also fall within this classifi-cation. However, if Cladium mariscus is not lo-cally dominant, the biotope should not be clas-sified within this type.

Cladium mariscus will occur on oligotrophic soilswhere it successfully out-competes other spe-cies at localities that are too wet for scrub veg-etation and too dry for reed beds (Rodwell 1995).Whether the vegetation type can be consideredas a 'wandering climax community' shifting inresponse to natural hydrological changes (in-cluding terrestrification and invasion by woodyplants) remains uncertain. In eutrophic habitats,other 'reed bed' species, e.g. common reed, oustCladium mariscus.

Natural range

The community type is restricted to south-east-ern Denmark, with the most abundant and larg-est sites on Bornholm, southern Zealand, Møn,and Lolland Falster (Mossberg & Stenberg 1994).Overall, the habitat type is relatively rare inDenmark and occurs predominantly in smalland scattered areas.

The type has been recorded at 32 sites, approxi-mately 270 ha in 10 SACs (Fig. 3.1.9). Two lo-calities support more than half of the total area:Søndersø near Maribo (13 habitats of 96 ha) andØlene on Bornholm (65 ha). Only one small sitehas been reported in Jutland. Another area of0.7 ha has been recorded outside the SACs. It isconsidered that the most extensive DanishCladium mariscus areas are included within theSACs but it is likely that missed examples of thiscommunity type also exist at a few other smalllocalities outside the SACs.

Considering the nature of the community type(as is the case for other oligotrophic wetlands),its present range is thought to constitute only asmall part of its former range occupied a fewhundred years ago, before drainage and culti-vation of swamps and mires really accelerated.

Structure and function

A wide range of conditions is considered vitalfor the long-term maintenance of this vegeta-tion type. The most important features are thehydrological regime, the level of eutrophicationand the intensity of grazing and mowing. Eng-lish studies show that a high, and preferably

Figure 3.1.9. Calcareous fens with Cladium mariscus andspecies of the Caricion davallianae (7210). Reported oc-currences of the natural habitat type in Denmark. Theboundary between the Atlantic region and the Conti-nental region is shown on the map.

1 The plant community class Caricion davallianae

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relatively stable, ground-water level, an absenceof eutrophication caused by fertilisation, drain-age water and nitrogen deposition are impor-tant preconditions for the type (Rodwell 1995).No precise studies of the consequences of graz-ing intensity are available, but experience gainedby the counties suggests that the grazing inten-sity in certain mires may be decisive for the bal-ance between species-rich alkaline fens (type7230), species-poor Cladium mariscus vegetation(type 7210), and woody plant vegetation, andthus for the long-term conservation of the type.In habitats on calcareous soils with a highground-water level and a low nutrient content,the community type is supposed to be relativelyresistant to overgrowth with woody plants.

For the recorded sites, the most frequentlyquoted threats to the conservation of this typeare woody plant encroachment (by such speciesas common alder, willow and birch species (7sites) and lowering or raising of the water level(4 sites). At four localities, eutrophication (as aconsequence of agricultural activities in the im-mediate environment) poses a substantial threatto the sites. In total, 17 sites, among them sev-eral of the largest, are reported to be subject toscrub invasion at various stages. However,whether the encroachment is occurring in thereed bed or about its periphery is not clear. Inthe only recorded occurrence in Jutland, SkærbroKær near Århus, scrub encroachment is so rapidthat the community type is disappearing. Oneof the most extensive localities, Søndersø in SAC156, is unique in having a very favourable con-servation status for the structure and functionof the type and has shown considerable benefitfrom raised water levels, which took place in1998. Although scrub encroachment was re-ported as the most critical threat, this may bebecause this change is easier to verify than moresubtle hydrological changes and eutrophication.There are no available data to show the level ofeffects of eutrophication on sites overall.

Twenty-two sites are subject to some regular in-spection. In the majority of these sites one ormore plant species are monitored by counts.Only at one locality, Urup Dam on Funen, haseffective monitoring been performed since 1984by repeated analyses of the vegetation in a per-manent test plot located in the grazed part ofthe fen. In the monitored test plot the vegeta-

tion type has proved robust to scrub encroach-ment by woody plants but there is an unmistak-able trend that Cladium mariscus is being replacedby Phragmites australis and Calamagrostis canes-cens.

Recording and monitoring of the type 7210 habi-tats suggest that grazing is a precondition of con-servation of alkaline fens (type 7230) which of-ten occur in close proximity with type 7210(Vinther 1987). Type 7230 supports many red-listed plant species, including species specifiedin the Habitats Directive. Even though grazingis estimated to be able to shift the balance be-tween type 7230 and type 7210 in the less wetmires, grazing should not be considered a threatto type 7210, whose most important habitat isthe wet reed bed.

Typical species

The only Danish species explicitly specified inthe Interpretation Manual is Cladium mariscus.This species is, by definition, abundant in alllocalities. At four sites the species is reported tobe increasing, probably as a consequence of thecessation of grazing in the natural habitat type7230. One site is reported to be completely over-grown with woody plants and in this case theconservation status of Cladium mariscus must becharacterised as unfavourable. In one occurrencethe species is declining in a permanently moni-tored test plot. Data clarifying the status of thespecies are not available from the remaining 26sites.

Apart from Cladium mariscus the most abundantspecies in the recorded sites are Phragmitesaustralis, Juncus submodulosus, Typha latifolia, Ca-rex lepidocarpa, and Molinia coerulea. Rare reedbed species and aquatic plants are Samolusvalerandi and the red-listed Teucrium scordiumand Potamogeton coloratus but it is not knownwhether these species can be considered to betypical of type 7210. Other species mentionedare supposed to be associated with alkaline fens(type 7230) occurring in contact with the type,including Juncus submodulosus, Carex flacca,Parmassia palustria, Pedicularis palustris, Briza me-dia, Limum catharticum, Pinguicula vulgaris,Dactylorhiza incarnata, D. najalis, Epipactis palus-tris and red-listed species such as Liparis loeselii,

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Gymnademia comopsea, Salix rosmarinifolia, andGentianella uliginosa.

Conservation status

The conservation status of natural habitat type7210 is assessed to be uncertain (Table 3.2). Thisassessment is based on a documented generaldecline in oligotrophic mires in Denmark andon the extensive overgrowth and unstable hy-drology being reported from the habitatsmapped. The monitoring of a test plot furthersuggests that other processes than scrub en-croachment may threaten Cladium mariscus. Theoverall conservation status must be character-ised as less certain, since time series are not avail-able to clarify the status of the type in themapped areas, especially in relation to impor-tant factors such as eutrophication, hydrology,mowing and grazing conservation management.

The assessment of the national range and statusof the type is equally subject to uncertainty, asthe current distribution outside the SACs is notknown. In addition, the interpretation of thedefinition of the type is not consistent and theaccuracy of the digitisation of the SACs duringthe registration process is of variable quality. Itis for instance not possible to determine whether,as suggested by the reporting, the type is disap-pearing from Jutland.

However, it is considered that in general theSACs adequately represent the vegetation typein Denmark.

3.1.10 7220* Petrifying springs withtufa formation (Cratoneurion)

Description

Type 7220 is defined as hard water springs wherecalcium carbonate (travertine) is precipitated asa result of a fall in CO2 partial pressure, for in-stance on mosses (calcium incrustation) even-tually generating travertine or tufa formations.The type is permanently wet from seeping cal-careous and mostly nutrient-poor water. Theformations are found in such diverse environ-ments as forests and open countryside. They are

generally small point or linear formations domi-nated by mosses (including the typical speciesCratoneurion commutatum). The very wet, oftennutrient-poor and calcareous formation withminimum temperature fluctuations means thattrees and tall herbs experience difficult growingconditions. This does not mean, however, thatthe type represents a climax community. Britishstudies prove that the type and its rare flora arefavoured by animal grazing and trampling. Thetype can form complexes with transition mires,fens, heaths, and calcareous grassland. To pre-serve this natural habitat type, which has a verylimited range, it is essential to preserve its sur-roundings and the whole hydrological systeminvolved (Anon. 1996). As the vegetation typeis dependent upon the whole hydrological sys-tem around the spring, it is necessary to differ-entiate the spring area and the diversified adja-cent areas. However, none of the reports havemade this differentiation, thus making the as-sessment of the conservation status of this natu-ral habitat type very uncertain.

Natural range

This type is rare in Denmark and occurs in ar-eas with calcareous formations in the subsoil incombination with spring fens or seeping groundwater. The type is therefore primarily occurringnorth and east of the line delimiting the extentof the ice cover during the last ice age. In total,36 sites distributed between 6 counties in 17SACs (Fig. 3.1.10) have been recorded. GrejsRiver Valley in the county of Vejle containsnearly one third of all localities. Other countieshave reported several spring areas on one datasheet making it impossible to assess each natu-ral habitat type. The total reported area was ap-proximately 103 ha. A Danish survey illustrat-ing the expanse of this natural habitat typewithin the SACs has not been made, but thereprobably remain important areas outside theSAC network.

Structure and function

The combination of calcareous, nutrient-poorand cold water means that the natural habitattype is only slowly affected by tree and scrubgrowth. Nevertheless, the type may be over-

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grown with woody plants and there is no doubtthat this natural habitat type with its typicalspecies, primarily mosses, is negatively influ-enced by scrub invasion. Grazing and tramplingor repeated scrub clearing are essential precon-ditions for the long-term maintenance of thetype. The most serious threat to the natural habi-tat type is undoubtedly a lowering of theground-water table. Eutrophication is anotherthreat to the naturally nutrient-poor ecosystem.To obtain a favourable conservation status it iscrucial to avoid any drainage or embankmentand lime quarrying in the areas surrounding thenatural habitat type.

For more than half of the sites (18) scrub inva-sion is reported to be a problem (4 unknown).Eight sites are reported to have become drier, 7are reported to face eutrophication problems,and at 4 localities fishponds are reported to con-stitute a potential threat. Planned golfing greensand other construction works are also indicatedas presenting a threat to the natural habitat type.The outcome is that structure and function ofthis fragile ecosystem are assessed to be unfa-vourable in 25 sites, 7 could not be assessed and4 are considered to have a favourable conserva-tion status.

Research on this natural habitat type in Denmarkis minimal. Six sites are subject to monitoring(17%). At five of these localities individual spe-cies, typically orchids occurring outside the

spring area, are being monitored. Monitoring ofthe entire natural habitat type is only takingplace at one locality.

Typical species

The typical Danish species include five mosses(Cratoneurion commutatum, C. commutatum var.falcatum, C. filicinum, Eucladium verticilliatumvery rare in Denmark, Catoscopium nigritum veryrare in Denmark, and one vascular plant (Pin-guicula vulgaris). Qualitatively and quantita-tively the mosses are the most important groupof organisms in the central part of the naturalhabitat type, the water spring area (Rodwell1991).

To assess whether the whole natural habitat typehas a favourable conservation status, it is neces-sary to assess whether the conservation statusof the typical species is favourable. The waterspring area is actually the heart of the type andthe most important typical species (Cratoneuroncommutatum) occurs only in this area. Therefore,it is essential to record the mosses in the springarea, or as a minimum the Cratoneuron-species.Information on recording of mosses is only avail-able from one habitat. An assessment of the con-servation status of the typical species would re-quire a time-series analysis. None of the datareported include a time series.

The occurrence of other species in the vicinityof the springs gives proof of a nature of conser-vation interest, as it hosts interesting speciessuch as Paludella squarrosa, Epipactis palustris, E.leptochila and E. atrorubens, Dactylorhiza incarnata,D. fuchsii, and D. najalis, Cephalanthera damaso-mium, and C. rubra, Corallorhiza trifida, Hermini-um monarchis, Monotropha hypopitys, Cypripediumcaleolus, Epipogium aphyllym, Platanthera chloran-tha, and species of community interest (Liparisloeselii, Saxifraga hirculus).

Conservation status

The conservation status of natural habitat type7220 must be assessed as uncertain (Table 3.2).This assessment is particularly based on the rela-tively high number of localities, which are be-ing invaded by scrub, and on the indications of

Figure 3.1.10. Petrifying springs with tufa formation(7220). Reported occurrences of the natural habitat typein Denmark. The boundary between the Atlantic re-gion and the Continental region is shown on the map.

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eutrophication reported. The uncertain assess-ment of the conservation status is due to the factthat first, the mapping is characterised by un-certainty concerning the definition and delimi-tation of the type, and second, that no time se-ries are available to illustrate the developmentof the type in the mapped areas in relation toessential structural and functional impact fac-tors such as eutrophication, hydrology, andmanagement of grazing or scrub clearing. Theassessment of the national range and develop-ment of the type are also subject to uncertaintyas the recent distribution outside the SACs isnot known, and the definition of the type in thereports is inconsistent. Finally, typical specieshave only been reported from one habitat.

3.1.11 9180* Tilio-Acerion forests ofslopes, screes and ravines

Description

Type 9180 includes forest areas on gravelly orstony soils and sloping grounds with mixeddeciduous forests with a distinctive componentof at least one of the following tree species: ash,elm, lime or sycamore maple. Another definingfeature is that no tree species should have acrown formation of more than 50%. The typeoccurs on slopes where intensive forestry and

agriculture are difficult. As for the other prior-ity forest types, the protection only includes for-ests not being subject to intensive forestry.

The forest type occurs especially on calcareousbut also on lime-deficient substrates. This foresttype hosts several, very diverse plant commu-nities, e.g. humid north-facing slope forests withspecies sensitive to withering and dry south-fac-ing slope forests supporting more robust spe-cies. A Danish survey of the ecology and vari-ety of the different vegetation types within thisnatural habitat type has not been made yet.

The successional stages of the type are not suffi-ciently known and it is therefore uncertainwhether the type can be regarded as a 'climaxcommunity' on appropriate habitats. Slightchanges in the conditions of the substrate or soilhumidity can produce a transition towardsbeech forests or oak forests. In Denmark, thestudy and description of this community typeis very incomplete.

Natural range

The type is relatively rare in Denmark, as it isprimarily occurring at localities, hardly accessi-ble for logging and handling machinery becauseof the undulating ground or administrative pro-tection. The total reported area is 593 ha, repre-senting approximately 1‰ of the total Danishforest area. The forest type is reported from 20localities distributed between 16 SACs (Fig.3.1.11). Quite a few of the largest localities haveto be re-assessed and probably be excluded fromthe registration as they do not comply with thecriteria of sloping ground and mixed growth.This applies to e.g. Frejlev Skov, Storskov, andRoden Skov on Lolland.

Structure and function

The most important preconditions for a long-term maintenance of the type are related to for-estry. Clear felling or conversion to tree speciesnot adapted to the locality are unquestionablythe greatest threats to the natural habitat type.Drainage and traffic with heavy machines andintensive cutting are also estimated to presentpotential threats.

Figure 3.1.11. Tilio-Acerion forest of slopes, screes andravines (9180). Special Areas of Conservation with re-ported occurrences of the natural habitat type in Den-mark. The boundary between the Atlantic region andthe Continental region is shown on the map.

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Lateral fertiliser displacement, ammoniumdeposition and pesticide drift are not consideredto be critical threats to the habitat type, as is mostoften the case, as this community is invariablysurrounded by other forest types. Where thevegetation type is not enclosed by a buffer zone,nitrogen fertiliser displacement from adjoiningcultivated areas can have a particularly nega-tive impact on the plant communities (bothgeophytes and epiphytes).

Of the 20 localities, 11 are near-shore forestsgrowing on more or less sloping grounds (slopeforests) with different sun exposures, 5 locali-ties are bordering large lakes, and 3 localities arenot close to any major wetlands.

The information on the soil characteristics is veryinadequate and provides no opportunity for gen-eralisation. Almost no data are available from 4of the habitats.

It is a well-known fact that deadwood in greatquantities is a fundamental structural param-eter for the biodiversity in the forest-ecosystem,but there are no reported data on the occurrenceof deadwood at the localities. The lack of infor-mation on deadwood can be explained by thefact that only 5 habitats have been visited withinthe last 5 years. Continuity is of vital importancefor many species but for only 25% of the sites isthere information relating to designation as anatural forest habitat.

Eight localities have been designated as un-touched forests, 5 are subject to extensive for-estry practising the coppice method or selectivefelling, 2 are still subject to continuously mod-erate forestry practises, whereas at 5 localitiesforestry activities are either unknown or diver-sified.

More than half (13) of the reported localities areconsidered to have a favourable conservationstatus, 5 can not be assessed based on the infor-mation available, and 2 localities have an un-certain conservation status owing to forestryactivities such as systematic felling of lime andsheep grazing. It is quite doubtful whether limeis able to regenerate under intensive sheep graz-ing.

Typical species

The Danish species specified in the Interpreta-tion Manual are: Acer pseudoplatanus, Fraxinusexcelsior, Carpinus betulus, Quercus sp., Corylusavellana, Taxus baccata, Ulmus glabra, Tilia cordata,Tilia platyphyllos, Actaea spicata, and Lunariarediviva.

One or more of the typical tree species are re-ported from 15 localities whereas the vegetationis not known from the last 5 localities. Herbs areonly reported from 2 localities, but none of thetwo herbs (Actaea spicata and Lunaria rediviva)are recorded. However, the lack of reports re-ceived on vascular plants is most probably notdue to an unfavourable conservation status, butrather that only 5 localities have been system-atically visited within the last 5 years. Three lo-calities are subject to monitoring including am-phibians and 2 vascular plant species. So it isnot feasible to assess the conservation status ofthe typical species of this natural habitat type.

Conservation status

The conservation status of habitat type 9180 isconsidered to be unknown (Table 3.2). The rea-son is that the majority of the reported localitiesdo not fulfil the criteria specified for this typeand that the type is only mapped in the stateforest districts.

However, with the reservations stated below, theconservation status of the reported localities isconsidered to be favourable. This positive as-sessment is substantiated by the fact that a rela-tively large proportion of the localities have beendesignated untouched forest or is being exten-sively managed. That means that the distribu-tion of the type in these areas must be charac-terised as stable. The special structures and func-tions crucial to the type will in the long term bemaintained in the untouched forest areas. Theassessment of the conservation status of the typi-cal species and their distribution is highly un-certain because of inadequate information. How-ever, it is estimated that the designation of sitesas untouched forests will contribute to ensur-ing a favourable conservation status of the typi-cal tree species.

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3.1.12 91D0* Bog Woodland

Description

Type 91D0 is defined as raised bog woodland orpeat bog woodland poor in nutrients. The areasare found on humid or wet peaty substrate, witha permanently high level of nutrient-poor wa-ter. The natural habitat type frequently occursin mosaic with other natural habitat types. It isoften found in contact with raised bogs (prior-ity natural habitat type 7110), and the type maysometimes be the first slow successional stagetowards a complete forest cover. An increasedpeat formation will eventually result in an oxy-gen-rich environment in the peat, facilitating theimmigration of trees.

For climatic reasons (Risager 1999) natural raisedbog woodland is not presumed to occur in Den-mark and this type should therefore rather beconsidered as degraded raised bogs (7120). Theoccurrence of actual marginal woodland on theraised bog is probably due to improved nutri-ent supply from, for instance, surface runoffwater. Peat bog woodland naturally occurs atoligotrophic lake banks where a peat layer hasbeen formed, and in oligotrophic forest bogs.

The ecology and floristic features of the naturalhabitat type has been little studied and is onlydescribed to a limited extent, reflected by thefact that Warming (1919) dedicates only 2 pagesto describe the natural habitat type in his com-prehensive study of the Danish vegetation. Thevegetation (including specifications of trees) inMaglemose in Gribskov was, however, very welldescribed when the site was protected in 1917(Petersen 1917).

The most abundant tree species are Betula pubes-cens, Frangula alnus, Pinus sylvestris, and Piceaabies. The last is not a native species in Denmark.The species found on the woodland floor arespecies adapted to the humid and oligotrophicecosystem, primarily Sphagnum spp., but alsoVaccinium oxycoccus, Carex spp., and Trientalis eu-ropaea.

Natural range

The natural habitat type is rare in Denmark with

a few localities distributed throughout most ofthe country. However, the absence of reportsaround the Great Belt region was remarkable.Because of drainage, the number of mires hasbeen decreasing during the last 200 years. C.Raunkjær stated in 1911: "When we considerhow our country was once filled up with miresand when we are now counting those remain-ing, untouched by culture, the result will appearto be rather depressing" (Warming 1919). Thistrend has been allowed to continue and the re-duction of wetlands in the period 1857-1988 hasbeen calculated to be 83% in 4 northern Zealandforest areas (Rune 1997) and this trend is mostcertainly characteristic of the whole country.Conversely, the historical patterns of land use,such as peat digging and mowing/grazing havestopped during recent decades, resulting inother changes in this natural habitat type.

The community type has been reported from 27sites distributed between 26 SACs (Fig. 3.1.12).One locality lies just outside a SAC. In total, thereported area extends to 1,095 ha. Holmegårdsmose is the largest locality amounting to 374 ha,an area that also represents several differentnatural habitats types. Quite a few of the areasreported comprise several natural habitat typesand the total area of reported localities is pre-sumably somewhat less than 1,095 ha. Severalof the reported areas should have been classi-fied as type 7120, degraded raised bogs. The re-

Figure 3.1.12. Bog woodland (91D0). Special Areas ofConservation with reported occurrences of the natu-ral habitat type in Denmark. The sites are centred inthe Special Areas of Conservation. The boundary be-tween the Atlantic region and the Continental regionis shown on the map.

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ported habitats are therefore not assessed toadequately represent the range of the naturalhabitat type at the national level. More private-owned areas belonging to this natural habitattype are supposed to be located within the SACs.It is assumed that there are also localities of thisnatural habitat type outside the SACs. Accord-ing to estimates, a moderate proportion of thelargest Danish localities are included in the re-ports, whereas only a small proportion of thesmall localities are covered.

Structure and function

The greatest threat to the natural habitat type isa lowering of the water table. The major reasonsfor this phenomenon is drainage, peat digging,extended water catchment, and selection of dif-ferent tree species (Rune 1997). The conversionto coniferous trees, especially Norway sprucewithin forestry during the last approximately200 years has also caused water dischargechanges.

Another threat to this oligotrophic ecosystem isthe deposition of atmospheric nitrogen. A thirdthreat to the type is the invasion of commonspruce, which is a non-native species in thisnatural habitat type in Denmark. An optimumassessment of the conservation status wouldrequire knowledge of the whole surroundingarea such as gradients in the ammonium depo-sition, selection of tree species, farming and wa-ter catchment within the drainage area. Suchdata are not reported for the localities and there-fore not included in the final assessment of theconservation status. It should be noted that evenif the actual site is administratively designatedan untouched forest, it might nevertheless bethreatened by external landscape-ecological con-ditions.

The quantity of information and the quality ofreports are differing considerably. Some of thereports (11 localities) are available as compiledreports from larger areas with geographicallyseparated localities reported on one data sheet.In 3 cases more than 30 areas representing thisnatural habitat type are reported on one singledata sheet, which means that the level of infor-mation reported varies and is subject to greatuncertainty. At 2 localities, monitoring is re-

ported to be ongoing, comprising both count-ing of orchids and a vegetation survey.

From more than half of the reported (15) locali-ties, data on the hydrological bog type are avail-able. Four habitats are reported to be located inclose proximity to former or existing raised bogs,3 are reported to be associated with a lake area,and 10 are reported to be fens.

More than a third (10) of the localities are desig-nated untouched forests or forests subject to se-lective-cutting in accordance with the naturalforest strategy. The extent of coniferous forestsin the surrounding areas is not reported at all.For 2 localities it is reported that far-reachingammonium point sources and large pigfarmsmay have a negative impact on the natural habi-tat type.

The information from 7 localities is so insuffi-cient that it is impossible to assess the conserva-tion status in terms of structure and function.Four habitats are reported to have become drier.From 3 of these 4 habitats it is furthermore re-ported that there is a risk of both lateral ferti-liser displacement and ammonium deposition.Based on the data reported, 16 habitats are as-sessed to have a favourable conservation status.

Typical species

Typical species are Agrostis canina, Betula pubes-cens, C. canescens, C. echinata, C. nigra, and Carexrostrata, Frangula alnus, Molinia coerulea, Trientaliseuropaea, Picea abies, Pinus sylvestris, Sphagnumspp., Vaccinium oxycoccus, Vaccinium uliginsosum,and Viola palustris.

None of the reports specify species data appro-priate for a time-series analysis that could re-veal inappropriate changes of the natural habi-tat type. Nobody has collected new species datafor this reporting process. From 12 localities nospecies are reported, from 5 one or two tree spe-cies are reported and from 10 localities herbsand/or mosses are reported. Applicable speciesdata are available from 5 of these 10 localities. Itappears that from 3 of these localities speciesnot actually belonging to this natural habitattype, such as Silene alba, Carex paniculata, Quercusrobur, and Platanthera bifolia have been reported.

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Such species may indicate that the type is chang-ing, but it is more likely that the type has beentoo widely defined and that species data origi-nate from a previous survey including a largerarea. The reported species data are so sparse thatit is not possible to integrate the typical speciesin the final assessment of the conservation sta-tus.

Conservation status

The conservation status of the habitat type 91D0is favourable (Table 3.2) due to the fact that scrubencroachment of previously open mires has be-come more common all over Denmark. How-ever, the assessment of the conservation statusis for several reasons uncertain. It is estimatedthat the reports are not representative of theSACs, as only state-owned areas have beenmapped. In addition, the type has been inter-preted quite differently in different areas, andthe accuracy of the digitisation of the naturalhabitat reports also differs greatly.

With substantial reservations (see below) theconservation status of the reported localities isconsidered to be favourable. The assessment ofthe conservation status of the data reported mustbe characterised as uncertain, as it is in generalnot based on time series, which could elucidatethe development of the type in the mapped ar-eas in relation to essential structural and func-tional impact factors such as hydrology, eutroph-ication and commercial forestry activities. Fi-nally, the reported species data are so insuffi-cient that they can not be integrated in the finalassessment of the conservation status. Particu-larly information on the structure and functionof the natural habitat type, the few reports onthreats to the type and the relatively largenumber of untouched areas substantiate the as-sessment of a favourable conservation status ofthe reported localities. As to the individual lo-calities, 16 are assessed to have a favourable con-servation status, 4 are assessed to have an unfa-vourable conservation status, and 7 can not beassessed due to lack of sufficient information.

3.1.13 91E0* Alluvial forests withAlnus glutinosa and Fraxinusexcelsior (Alno-Pandion, Alnionincanae, Salicion albae)

Description

In Denmark type 91E0 is defined as areas with-out any stagnant water and dominated by alderand/or ash. The type is therefore typically lo-cated in riparian areas or in areas with somewater flow, e.g. in the margin zone of springs orspring fens. Even a single row of trees (arbores-cent galleries) of common alder along water-courses or springs is included. So are also areaslocated on raised marine sediments where theroots can reach non-stagnant, oxygen-richground water. The natural habitat type typicallyoccurs on heavy soils, but it can also be foundon light soils periodically inundated by the an-nual rise of the water level, but which are other-wise well-drained and aerated during low-wa-ter. Some of the typical species specified, e.g.Anemone nemorosa, Carex sylvatia, and Urticadioica suggest that the definition of the typeshould be interpreted widely and also includenatural successional stages with deposits of somuch organic matter that suggest that annualfloodings have ceased. If the succession proceedsto further deposit organic matter, trees tolerantof shade such as beech will be able to invadethe area. Young or intensively cultivated forestswithout species of community interest are notincluded in the Habitats Directive. In terms ofvegetation ecology the studies of this type arefairly moderate in Denmark compared to ourneighbouring countries (Prieditis 1997).

Natural range

The typical tree species common alder and ashcan not succeed on acid and nutrient-poor soilsand the natural habitat type is therefore rare inthe western part of Jutland (Ødum 1980), where-as it is common in the eastern part of Denmark.

The total area mapped is 662 ha, correspondingto 1.5 ‰ of the total Danish forest area. The typehas been reported from 65 localities distributedbetween 36 SACs (Fig. 3.1.13). It is estimated thatthe type occupies several localities within the

48

SACs and that it is common outside the SACs.The public-owned areas represent 67% of thereported localities, reflecting a misrepresentationof data as at the national level the public-ownedforest areas represent only 31% of the total re-source. Many important private-owned areashave not yet been mapped. It is also consideredthat the reported data represent only a small partof the total area covered by this type.

From 3 localities the natural habitat type is re-ported to be progressing at the cost of other valu-able natural habitat types. From one habitat, thetype (91E09) is reported to be expanding at thecost of other and rare natural habitat types (7210*Calcareous fens with Cladium mariscus and 7230Alkaline fens).

Structure and function

The greatest threats to these alluvial forests haveundoubtedly been drainage and conversion tomeadow or to other tree species, threats thatwere already identified by Bornebusch (1914)and Vaupel (1863). However, none of the re-corded habitats are reported to have becomedrier and the type is nowadays generally pro-tected against status changes under section 3 ofthe Protection of Nature Act.

All localities are either unchanged, have becomewetter or have unknown conditions. It should,however, be noted that for 40 of the localitiesthis statement is based on undocumented assess-ments. From 2 habitats felling intensities are re-ported to have a negative impact on the naturalhabitat type. The level of detail in the reporteddata differs considerably. Eleven reports com-prise several geographically separated localitieson one data sheet making it impossible to as-sess the individual localities. In 2 cases morethan 50 areas representing the natural habitattype have been summarised on one data sheet.The areas around Søndersø near Maribo (9 lo-calities) and Røgbølle Sø (6 localities) have alsobeen reported without any differentiation of theindividual areas. Unfavourable impacts fromagricultural activities have only been reportedfrom a few of the localities. This is probably dueto the fact that the majority of the localities aresurrounded by other forest types acting as bufferzones. From one site, there is a reported risk oflateral fertiliser displacement but no pesticidedrift is reported. From one area there is a re-ported risk of ammonium deposition from apigfarm. Finally, 5 localities are reported to beexposed to the risk of erosion caused by visi-tors.

Only 22% of the reported functional qualities ofthe natural habitat type are based on facts orexact knowledge and only 3 localities are in-cluded within the provisions of a monitoringprogramme.

Approximately half (49%) of the reported locali-ties are located in the immediate proximity of alake, 38% are located in springs, and only 9%are riparian localities. Another 8% are locatedin ravines or on slopes. Approximately half ofthe localities have been designated untouchedforest (30), forest with selected felling (1), andcoppice wood (1) in accordance with the natu-ral forest strategy. Sixteen localities are reportedto be subject to forest protection duty.

Deadwood in great quantities is an essentialstructural parameter for the biodiversity in theforest ecosystem (Aude et al. 2000), and that alsoapplies to type 91E0. Deadwood is reported from2 localities. Continuity is of vital importance formany species. Twenty percent of the localitiesare reported to be natural forests.

Figure 3.1.13. Alluvial forests with Alnus glutinosa andFraxinus excelsior (91E0). Special Areas of Conserva-tion with reported occurrences of the natural habitattype in Denmark. The sites are centred in the SpecialAreas of Conservation. The boundary between theAtlantic region and the Continental region is shownon the map.

49

Typical species

The Interpretation Manual (Skov- og Natursty-relsen 1999a) specifies 23 typical species: Ane-mone nemorosa, Anemone ranunculoides, Ficariaverna, Angelica sylvestris, Cardamine amara andC. pratensis, Carex acutiformis, C. pendula, C. re-mota, C. strigosa, and C. sylvatia, Cirsium olera-ceum, Equisetum telmateria, Equisetum spp., Fili-pendula ulmaria, Geranium sylvaticum, Geum ri-vale, Lycopus europaeus, Lysimachia nemorum, Ru-mex sanguineus, Stellaria nemorum, and Urticadioica. Seven woody plants are also specified:Alnus glutinosa, A. incanae, Betula pubescens, Fra-xinus excelsior, Salix alba, S. fragilis, and Ulmusglabra.

Time series to assess the changes in status ofspecies typical of the natural habitat type are notavailable. No species data are reported frommore than half of the localities (35). From 23 lo-calities only trees and bushes have been re-ported. Complete species lists are only reportedfrom 7 sites. Only 2% of the potential species inthe 65 localities have been reported implyingthat there is no basis of assessing the conserva-tion status of the typical species.

This natural habitat type is most certainly bothqualitatively and quantitatively the principalhabitat for mosses in the forest ecosystem (Audeet al. 2000), but no reports on mosses have beenpresented.

Conservation status

The conservation status of habitat type 91E0 isunknown (Table 3.2). The national conservationstatus can not be assessed on the basis of theexisting mapping. First, the type is only consist-ently mapped in state-owned areas, and secondthe interpretation of the definition differs.

More than half of the reported localities (36) are,however, assessed to have a favourable conser-vation status. Seventeen localities are assessedto have an uncertain conservation status. From12 localities no data that can elucidate the con-servation status have been reported. The assess-ment is also uncertain due the insufficient docu-mentation on typical species, successional proc-esses, forestry, and hydrology.

3.2 Non-priority natural habitattypes

Half of the counties (7) have reported data on'non-priority natural habitat types'. In total, datafrom 32 different natural habitat types distrib-uted between 37 SACs have been reported rep-resenting a mean number of three reports pertype. Two non-priority natural habitat typesoutside the SACs have been reported. The con-clusion is that the data basis is so incompletethat an assessment of the conservation status ofthe non-priority natural habitat types can notbe made.