Climate Change, adaptation and management of risks to boreal forests

Prof. Heli Peltola, School of Forest Sciences, University of Eastern Finland 

Global climate change (CMIP5, IPCC 2013) and impacts to Finland

Global change in mean T (oC)       Finland: Changes in mean annual T (oC)  and Prec. (P, %) 

T change

(oC) 

T change

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Climate Change may increase many abiotic and biotic risks to forests

Finnish case study: Both unfrozen soil and wind > 10 m/s (1971‐2000)

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Helsinki (N 292)

Joensuu (N 46)

Jyväskylä(N 99)

Kajaani (N 117)

Kauhava (N 173)

Rovaniemi(N 237)

Sodankylä(N 39)

Weather station

frost depth < 1 cm frost depth 1-20 cm frost depth 21-40 cmfrost depth 41-60 cm frost depth > 61 cm

Black line corresponds frost depth of about 20-30 cm in forest soil (in figure it is shown frost depth classes for snow free road, which are double!)

‐ Since 2050 there will probably be no frozen soil conditions frequently in southernFinland, increasing the risk of wind damage, although the severity and frequency of storm winds may not increase (since 2000, in total of 24 milj. m3 of timber damaged in Finland in different wind storms).

(Gregow et al. 2011)

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Figure legends:OMT: very fertile site (dominant species: Norway spruce, birch) MT: medium fertile site (Norway spruce, birch, Scots pine)VT: less fertile (quite dry) and  CT: poor (dry) site (Scots pine)

Climate change may increase drought especially on soils with low  water holding capacity  

Forest ecosystem model SIMA

(Kellomäki et al.  2008)

Effects of current and changing climate (RCP4.5 and RCP8.5) on ecosystem carbon stock of Finnish forests in 2010‐2039, 2040‐2069 and 2070‐2099 

‐ Forest management followed in forest ecosystem model (SIMA) simulations the current Finnishmanagement recommendationson NFI plots on upland forestsites.

‐ In addition to climate change, also prevailing growingconditions (climate, site), current forest structure (age, stocking, species) and intensityof forest management affectsthe results largely. 

(AlRahahleh et al., unpublished)

Effects of current and changing climate (RCP4.5 and RCP8.5) on growth of Finnish forests in 2010‐2039, 2040‐2069 and 2070‐2099 

‐ The volume growthincreases both under thecurrent climate and warming climate, and therelative sense most in north.

‐ Under the warmingclimate (especially withRCP8.5) the growth evenreduces in south.

(AlRahahleh et al., unpublished)

Relative effects of changing climate (RCP4.5 and RCP8.5) on growth of Finnish forests in 2010‐2039, 2040‐2069 and 2070‐2099 

‐Under drastic climatewarming, the growthreduces in south in shallow rooted Norwayspruce as growingconditions become sub‐optimal for it  especiallyon soils with low waterholding capacity.

(Peltola et al., unpublished)

Southern Finland   SRES scenarios Northern Finland

Climate sensitivity of volume growth of young Norway spruce, Scots pine and birch on sites with different fertility in Finland (2010‐2069)

(Torssonen et al. 2015)

Effects of forest management on wind damage risks to boreal forests?  

(Photo: Heli Viiri)

Mechanistic wind damage risk model HWIND

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Height/DBH ratio 1:100

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Scots pine Norway spruce Birch

(Peltola et al. 1999)

Wind, m/s

SIMA_HWIND model simulations: Wind speeds (m/s) uprooting trees

(Ikonen et al., unpublished)

2070‐2099: Effects of species preference on medium fertile sites

Windspeed, m/s

Currentclimate

(Ikonen et al., unpublished)

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Forest area of 360 ha in  Central Finland : Scots pine 10.4, Norway spruce 46.1 and  Betula sp.  43.4 % of total volume; MONSU model     

(Zubizarreta Gerendiain et al, unpublished)

Effects of  wind damage risk on optimal management of a landscape

Potential climate change (CC) impacts, vulnerability and adaptation measures  in boreal forestry 

Climate change  (CC) impacts 

Sensitivity/Vulnerability to CC

Possible adaptation measures

‐Higher  temperature, and increase of precipitation, but also risk of drought‐ Longer growing season‐Higher atmospheric CO2 concentration‐ Reduced duration of frozen soils‐ Reduced carrying capacity of soils‐ Increased frequency of high wind speed during  unfrozen soil conditions

‐Enhanced seed crop, with higher potentials for natural regeneration‐Increased total growth, but reduction in Norway spruce in south on the soils with low water holding capacity  ‐Enhanced growth of ground cover vegetation, disturbing forest regeneration‐Short supply of nitrogen in relation to growth potential‐Increased risks by wind and snow damage and insect/fungus attacks

‐Use proper soil preparation to reduce the competition of the ground cover in forest regeneration ‐Use forest fertilization if needed‐Prefer natural regeneration if appropriate‐ Use proper site specific tree species(genotypes) and improved seedmaterial/seedlings in regeneration‐Prefer mixed stands if site conditions aresuitable‐Adapt thinnings (timing and intensity) to meet the enhancing growth and to enhance the resistance of forests to abiotic and biotic damages ‐ Shorten rotation length if needed to consider silvicultural risks(Kellomäki et al. 2005)

• We need to gradually adapt forest management to the projectedclimate change, considering both various risks to forests andforestry and uncertainties related to the climate change, becausemeasures applicable now or in near future may not be valid later.

• Growing mixed forests is a value for future as it is no sense to ”putall eggs in same basket”, in the view of risk management.

Conclusions

FORBIO: Sustainable, climate‐neutral and resource‐efficient forest‐based bioeconomy (www.uef.fi/forbio, twitter @FORBIOproject)  

Research Partners of ConsortiumUniversity of Eastern Finland, School of ForestSciences, UEF (leader and vice‐leader of consortiumand team 1 Prof. Heli Peltola and Prof. Jyrki Kangas)  UEF, Department of Chemistry (leader of team 2 Prof. Janne Jänis)Finnish Meteorological Institute (leader of team 3 Docent Ari Venäläinen) Natural Resources Institute Finland (leader of team 4 Prof. Antti Asikainen) European Forest Institute (leader of team 5 Prof. Lauri Hetemäki) Finnish Environment Institute (leader of team 6 Prof. Pekka Leskinen)