The Munessa project: An Ethiopian perspective on functional ......C. lusitanica 2002-2003 2001-2002...

The Munessa project:

An Ethiopian perspective on functional ecology and

management of mountain forests

The Munessa GroupGeorg Guggenberger*, Erwin Beck, Achim Bräuning, Florian Fritzsche, Bruno Glaser, Hany El Kateb, Ingrid Kottke, Reinhard Mosandl, Klaus Müller-Hohenstein, Andreas

Nenninger, Daiel Rückamp, Simone Strobl, Wolfgang Zech

Alemu Gezahegne, Asferachew Abate, Aster Gebrekirstos, Demel Teketay, GetachewTesfaye, Girma Abebe, Masresha Fetene, Tesfaye Wubet

*Institute of Soil Science, Leibniz University Hannover

„Interdependencies between upland and lowland agriculture and resource management“University of Hohenheim, 1-4 April 2008

The Munessa forest project, Ethiopia

Photos by Klaus Müller-Hohenstein

People arerelying on forest products fortheir ownutilisationand theirpersonal income

The problemNatural forests in Ethiopia

• High population growth rates(2.3% in 2006)

• Deforestation due to increasingdemands for agricultural landand timber

• Difficulty of regeneration due toheavy grazing

• Loss of biodiversity• Soil degradation and

environmental deterioration

⇒ Decreasing elasticity of ecosystemsand increasing vulnerabilityagainst environmental stress

The present-day responseForest Plantations

• Exotic tree monocultures, e.g.- Eucalyptus spp.- Cupressus lusitanica- Pinus patula

• Rotation time about25 to 35 years

• Consequences for- productivity- carbon storage and cycling- biodiversity- re-establishmentof native species

- potential utilizationof local people

⇒ Sustainability questionablePhoto by Klaus Müller-Hohenstein

Clear cut of Eucalyptusplantation

„Private cut“

of plantation

trees


Goals


Understanding of the functioning of mountain forests• Knowledge and integration of ecological key processes

- Water fluxes- Nutrient fluxes- Carbon fluxes- Diversity- Regeneration

• Needs and utilization of forest by local population

⇒ Interdisciplinary approach is necessary

Development of concepts for sustainable forest management⇒ Interaction with governmental institutions, forest

enterprises and local communities

Case studies in the Munessa forest

• Ecological gradient from semi-arid Zuway-Shalla Basin to subhumidArsi Highland

• Geological substrate is homogenous, intermediate volcanic rock

Kuke


Ecological gradient of the study area


Process studiesat Kuke

Podocarpusfalcatus



Comparative studies atindividual tree level

• water, nutrient andcarbon dynamics inthe soil-plant system

• regenerationecology

• structure and functionof mycorrhiza

⇒ implications forforest management

Soil-plant hydrology and nutrient dynamicsLiving fine roots and root architecture

C. lusitanica

LFR (g m-3)

0 1000 2000 3000 4000 5000 6000

Soil

dept

h (c

m)

10

35

60

85

100

Dry season (1m distance)

Wet season (1m distance)

Dry season (2m distance)Wet season (2m distance)

a

Total LFR: 0.88 kg m-2

E. globulus

LFR (g m-3)

0 1000 2000 3000 4000 5000 6000

Soil

dept

h (c

m)

10

35

60

85

100

c


Cupressus

P. falcatus

LFR (g m-3)

0 1000 2000 3000 4000 5000 6000

Soil

dept

h (c

m)

10

35

60

85

100

b


Podocarpus Eucalyptus


Soil-plant hydrology and nutrient dynamicsSap flow in three native tree species

Total daily transpiration(mm H2O day-1)

0 1 2 3 4

Cupressuslusitanica

Podocarpusfalcatus

Eucalyptusglobulus

Wet periodDry period

• C. lusitanica high transpiration during wet period• E. globulus high transpiration during dry period


Soil-plant hydrology and nutrient dynamicsSap matrix potential under different trees

• Soil under C. lusitanica is much drier than under P. falcatus• Soil under E. globulus is moist taps from deeper ground

Mean difference in matric potential to P. falcatus (hPa)

-100 -50 0 50 100 150

0

50

100

150

200

250

***

*

***

***

***

***

***

***

***

***

***

*** ***

**

**

**

2002-2003 2001-2002

C. lusitanica2002-2003 2001-2002

E. globulus

Soil

dept

h(c

m)

2001-02wet year

2002-03dry year


Soil-plant hydrology and nutrient dynamicsNitrogen leaching under different trees

• Pronounced nitrate losses under Cupressus lusitanica

Median NO3- concentrations [mg L-1]

0 5 10 15 20

Naturalforest

Eucalyptusglobulus

Cupressuslusitanica

20 cm50 cm100 cm


Regeneration ecologyRegeneration of P. falcatus under the canopy of exotic tree species

• There is a higher germination success of the indigenous treespecies Podocarpus falcatus under the canopy of exotic treespecies than under the natural canopy

Regeneration of P. falcatusunder different forest types

Relative growth rates of P. falcatusunder different forest types

dens

ity [s

aplin

gs/h

a]

0

500

1000

1500

2000

605

1188

1545

NaturalForest

EucalyptusSite

PinusSite

NF ES PSR

GR

[mm

/mon

th c

m]

0

1

2

3

4

0.36

1.13

0.52


PinusSite

EucalyptusSite

NaturalForest

Regeneration ecologyGenerally good regeneration of native species in some plantations

• Advantageous light climate under E. globulus• Good water supply in surface soil under E. globulus

Regeneration in E.globulus plantation

Relative growth rates0.0 0.5 1.0 1.5 2.0 2.5 3.0

Crotonmacrostachyus

Prunusafricana

Podocarpusfalcatus

shadegapopen

Relative growth rates at different light conditions



• Mycorrhizal community is diverse and• Differs between nurse tree and regenerating tree species

Consensus network of mycorrhizal fungi of Cupressus lusitanica(nurse tree), Prunus africana and Podocarpus falcatus

Mycorrhiza in plantation forests

Regeneration ecology

The landscape dimension


Agriculturein the lower

savanna

Forest borderat the lowersavanna


Homesteadat the upper

forest border

Agriculturein the uppersavanna

Human impact (landscape level)Land use map developed from aerial view

• Clear border at the lower margin of the Munessa forest (forest plantations)• Fragmentation at the upper margin due to settlements


lower savanna upper savanna


N storage in soils (t ha-1 50 cm-1) along the altitudinal gradient

Exchangeable K in soils (kmolc ha-1 50 cm-1) along the altitudinal gradientlower savanna forest upper savanna

Major findings so far

Individual level• Water-use strategy differs strongly between the different

tree species• The same is true for nutrient cycling• Regeneration of indigenous tree species is possible• Eucalyptus and Pinus are promising nurse trees,

possibly due to favorable light climate and water supply

Landscape level• Human influence and elevation gradient are the two

master variables controlling distribution patterns• Agroforestry appears to be a promising option

Investigations at stand level and silvicultural experiments just started


Science and education - making use of a field stationThe Munessa Project field station at Kuke(funded by DFG/BMBF and managed by Addis Ababa University)

• provides accomodation• enables easy access to field sites• offers basic working facilties

Opportunities forqualification

• BSc/MSc studies

Training activities• Summer schools• Joint Ethiopian-

German fieldcourses

• Training forprofessionals

Open for guests• Scientists

• Study/training


We are grateful to DFG for fundingthe Munessa project

Thank you


Central objectives of the next phase

Identify key ecophysiological traits of important functional typesat the individual tree level

• Carbon, water, nutrient relations of different life forms

Assess ecosystem attributes with respect to process regulation andstability at the stand level

• Climate-growth relationships using dendrochronology

• Below-ground carbon cycling and soil organic matterquality and turnover

Identify options for sustainable management of forest resources• To evaluate appropriate silvicultural management options

(conversion, intensive promotion, enrichment plantings)

• Inventory and monitoring system for forest managementand conservation


Overview of silvicultural experiments

Age classTree species Protection by Fencing (+)

ControlControl(0)(0)

ConverConver--sionsion (2)(2)

Intense proIntense pro--motion (1)motion (1)

No Protection (-)

ControlControl(0)(0)

ConverConver--sionsion (2)(2)

Intense proIntense pro--motion (1)motion (1)

(years)

Eucalyptus(C) III (17-24) C III + 0 C III + 2C III + 1 C III - 0 C III - 2C III - 1

Cupressus(A)

I ( 2- 8) A I + 0 A I + 1 A I - 0 A I - 1

II ( 9-16) A II + 0 A II + 1 A II - 0 A II - 1

III (17-24) A III + 0 A III + 2A III + 1 A III - 0 A III - 2A III - 1

IV (≥ 25) A IV + 0 A IV + 2A IV + 1 A IV - 0 A IV - 2A IV - 1

New plantation A 0 + 0 A 0 + 1 A 0 - 0 A 0 - 1

Pinus(A)

I ( 2- 8) A I + 0 A I + 1 A I - 0 A I - 1

II ( 9-16) A II + 0 A II + 1 A II - 0 A II - 1

III (17-24) A III + 0 A III + 2A III + 1 A III - 0 A III - 2A III - 1

IV (≥ 25) A IV + 0 A IV + 2A IV + 1 A IV - 0 A IV - 2A IV - 1

New plantation A 0 + 0 A 0 + 1 A 0 - 0 A 0 - 1


Working in EthiopiaEthiopian partners• Addis Ababa University

(Prof. Dr. Masresha Fetene, Dr. Sileshi Nemomissa)• Ethiopian Institute for Agricultural Research

(Dr. Solomon Asefa, Dr. Alemu Gezahegne)• Wondo Genet College of Forestry

(Dr. Zebene Asfaw, Dr. Aster Gebrekirstos)• Forest Stewardship Council, Regional Office Africa

(Dr. Demel Teketay)

Ethiopian students• Ethiopian PhD and MSc students

Stakeholders• Governmental and non-governmental organizations

(e.g., Shashemene-Munessa Forest Enterprise)• Local population


Regeneration ecologyBeneficial modulation of the light climate of young trees by shelter trees

The extent of the nurse tree-effect strongly depends on the structure of the nurse (shelter) tree canopy

• Natural forest: Closed canopy, low light intensity, few light flecks• Eucalyptus forest: Partly closed canopy, moderate light, many light flecks• Pinus forest: More open canopy, optimal light intensity, moderate light flecks

Mitigation of peaks oflight intensity

Achievement of light flecks(stimulation of photosynthesis)

time 00:00 04:00 08:00 12:00 16:00 20:00 00:00

Sola

r rad

iatio

n [W

/m²]

0

25

50

75

100

Sola

r rad

iatio

n [W

/m²]

0

500

1000

1500

2000Natural Forest bottomPinus Site bottomoutside

Daily course of solar radiation in the open site, inside the natural forest and the Pinus forest (height of sensor 1.5 m)

-1,0

0,0

1,0

2,0

3,0

4,0

5,0

6,0

9:00 12:00 15:00 18:00time

Assi

mila

tion

[µm

ol m

-2 s

-1]

0

200

400

600

800

1000

1200

1400

PAR

[µm

ol m

-2 s

-1]

Assimilation PAR top

Daily course of assimilation of a P. falcatus sapling (height 2.0 m) and PAR in the Pinus forest


„Natural“Ecosystem

ForestManagement

UncontrolledDisturbance

Ecosystemfunctions

and services

AnthropogenicEcosystem

Unsustainable

Sustainable

Water cyclingNutrient cyclingCarbon cyclingDiversityRegenerationProductivity

(Coexistenceof variousfunctional

types)

The conceptional framework


Jointexperiments

Example ofexperimentaldesign at siteKuke


Guggenberger / Fetene

Belowground Carbon Cycling

Glaser / Zech

Soil Organic Matter and Nutrient Dynamics

Beck / Fetene / Demel

Ecophysiology ofIndigenous Trees

Bräuning / Gebrekirstos

Tree Growthand Climate

StructureScale

Regionallevel

Standlevel

61 m

61 m

Buffer zone

25 m

25 m

Inner plot

Individualtree level

Read, 2002

Central ProjectManagement,

Database,Integration

Mosandl / El Kateb

Management Options in Plan-tation and Natural Forests


Tasks and collaborationof group Beck et al.(EcophysiologicalParameters):

1. Water relations:Uptake of soil water from several depths (soil matricpotential - δ18O of water -stem water transport)Diurnal storage of water inthe tree (sensitive dendro-

meters - leaf water potentialLeaf & whole-tree transpiration

2. Carbon relations:Carbon uptake (photosynth.)Leaf respiration in relation tophotosynthesisRoot respiration (auto andheterotrophic respiration)

3. Nutrient relations:Nutrients in soil and plant(Nutrient analysis in soil,soil water, leaves and roots)

4. Growth:Stemgrowth: Height & diameterFine root growth

Guggenberger / Fetene

Belowground Carbon Cycling

Glaser / Zech

Soil Organic Matter and Nutrient Dynamics

Beck / Fetene / Demel

Ecophysiology ofIndigenous Trees

Bräuning / Gebrekirstos

Tree Growthand Climate

Example of collaboration

Mosandl / El Kateb

Management Options in Plan-tation and Natural Forests

Growth & diurnal water storage

Nutrients in soil & plant

Water relations &

carbon cycling


Organization

• Five individual German-Ethiopian projects addressingimportant aspects of the Munessa forest

... using synergistic effects of a project package ...

• Shared key hypotheses

• Implementation of joint experiments and data sharing

• Coordinating scientist- Project management- Integration (e.g., manual, publications)

• Mutual support in infrastructure maintenance

• Common database (will be based on that of FOR Ecuador)


The Munessa project: An Ethiopian perspective on functional ......C. lusitanica 2002-2003 2001-2002...

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