Pekka Nöjd / Pekka Nöjd /

BACKGROUND INFORMATION:

Societas pro Fauna et Flora Fennica Climate Change Symbosium 26.11.2005House of Sciences (Tieteiden talo), Kirkkokatu 6, Helsinki

Kari Mielikäinen, Finnish Forest Research Institute

Finnish Forests and Climate Change Finnish Forests and Climate Change

Societas pro Fauna et Flora Fennica homepage: http://www.societasfff.fi/

Pekka Nöjd

Metsäntutkimuslaitos Skogsforskningsinstitutet Finnish Forest Research Institute www.metla.fi

http://www.societasfff.fi/

Pekka Nöjd

Metsäntutkimuslaitos Skogsforskningsinstitutet Finnish Forest Research Institute www.metla.fi

Climate change and Finnish Forests

Kari Mielikäinen 25.11.2005 METLA

Siberian larch, age 100 000 years +

Content of the Talk

1. History of Finnish forests (Ice Age … 1920)2. Air pollution and forest growth (1980 … 2000)3. Growth Trends in European Forests4. Climate Change and Finnish Forests

Can we see it?

What are the impacts?

Uncertainties?

What should the scientists do?

The history of Finnish forests after the latest Ice Age

First pine and birch trees came to Lapland 8000 years ago, Norway spruce 3000 years ago

The climate was clearly warmer 5000 years ago

Pine was growing north of the present tree line

DOMESTIC PROBLEM:The Utilisation of Finnish forests 1500…

• Slash and burn

• Tar distillation

• Dimension cuttings

• Sustainable forest management 1920…

© Metla/Olli Heikinheimo

REGIONAL PROBLEM:Impacts of air pollution on European forests

Situation in the 1980´s Sulphur (SO2) Acid rain Deposition of nitrogen (traffic and agriculture) Deposition of heavy metals

==> In spite of these facts (next two slides)

Total increment and drain of Finnish forests

0

20

40

60

80

100

19231930 1940 1950 1960 1970 1980 1990 2000

Mio.m³

Increment

Drain

© Metla/Erkki Oksanen

04/21/23E U R O P E A N F O R E S T I N S T I T U T E

Increment and fellings in European forests

Sources: years 1950-1990: Kuusela, K. 1994. Forest Resources in Europe. European Forest Institute. Research Report 1. year 2000: UN-ECE/FAO. 2000. Forest Resources of Europe, CIS, North America, Australia, Japan and New Zealand.

0

100

200

300

400

500

600

700

800

1950 1960 1970 1980 1990 2000

mill

. m3/y

ear

In exploitable forests 1950-1990 (133 mill. ha in 1990), in forests available for wood supply 2000 (149 mill. ha in 2000)

Gross annual increment

Net annual increment

Annual fellings

METSÄNTUTKIMUSLAITOS

SKOGSFORSKNINGSINSTITUTET

FINNISH FOREST RESEARCH INSTITUTEwww.metla.fi

LAUCHING OF A PROJECT BY METLA AND UNI FREIBURG IN 1992 ”GROWTH TRENDS IN EUROPEAN FORESTS”

“HAS FOREST (TREE) GROWTH IN EUROPE CHANGED IN A WAY, THAT CANNOT BE EXPLAINED BY CHANGES IN STAND STRUCTURE OR SILVICULTURE?”

Here: Growth trend = long-lasting deviation from expected growth (Tree age and stand density

excluded)

==> 45 forest growth scientist from 12 countries

•STUDY MATERIALS:

OLD DATA FROM:

1. LARGE-AREA INVENTORIES2. LONG-TERM PLOTS OR EXPERIMENTS3. UNTOUCHED OLD FORESTS (NATURE

RESERVES)

© Metla/Arvo Helkiö

Growth Trends in European Forests: Conclusions(Spiecker, Mielikäinen, Köhl & Skovsgaard 1996)

Possible causes for increasing growth trends in Central Europe

• Land use history and forest management

• Natural disturbances– fire, insects, drought, storms– natural variation of the climate

• Human influence on the environment – Nitrogen deposition MOST IMPORTANT FACTOR

GLOBAL PROBLEM:Climate change in Finland

• CAN WE ALREADY SEE IT?

• WHAT ARE THE IMPACTS ON FORESTS?

© Metla/Reino Saarnio

Annual ring index of Scots pine and July temperature in Sodankylä, Lapland

10

12

14

16

18

20Temperature of July, Sodankylä

50

75

100

125

150 Tree-ring index, Sodankylä

1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000

Mean temperature December-March in Sodankylä, Lapland

Mean temperature April – May in Sodankylä, Lapland

Annual ring index of Sodankylä in a longer time-scale

1750 1800 1850 1900 1950 2000

40

60

80

100

120

140

160

180

Tre

e-r

ing

in

de

x

Year

• What are the impacts on forest(ry)?

The impact of increasing temperature on tree growth in Finland

•

• Modeling (Kellomäki 1990´s) – CO2 + heating in

plastic tents + modeling

– temperature rise of 4 °C +30-50 % in growth

© Metla/Erkki Oksanen

• Experimental data (Heikinheimo 1920-2000)

– seed origins between Germany and Finnish Lapland

– temperature rise of 4 °C +100 % in growth

Impacts on forest management

• Selection of tree species– Norway spruce, broadleaved trees

• Harvesting technologies– no frost –> problems with machines

• Wind damages– changed stand structure (planted spruce)

inceasing risks

• After effects– fungi, insect damages

Uncertainties in forecasts

• Too simple models

• Variation of North Atlantic Oscillation (NAO)

• Heat pumps of the oceans (Golf stream) may change

• Long-term ”unknown” variation of tree growth (Dendrochronology)

What should the scientists do? • Meteorological

observations

• Analysis of annual rings (yearly basis)

• Monitoring of tree growth (daily basis) using girth bands

• Modeling

CLIMATE CHANGE

CAN WE SEE IT? NOT YET IN FINLANDIS IT COMING? PROCESSES ARE KNOWNIMPACTS ON TREES? GROWTH INCREASE

NEGATIVE IMPACTS

WHAT TO DO? FIGHT AGAINST

THANK YOU! Pekka Nöjd

Metsäntutkimuslaitos Skogsforskningsinstitutet Finnish Forest Research Institute www.metla.fi