Kirschbaum, M. & Fischlin, A., 1996. Climate change impacts on forests. 
        In: Watson, R., Zinyowera, M.C. & Moss, R.H. (eds.), Climate change
        1995 - Impacts, adaptations and mitigation of climate change:
        scientific-technical analysis. Contribution of Working Group II to 
        the Second Assessment Report of the Intergovernmental Panel of Climate 
        Change (IPCC). Cambridge University Press, Cambridge a.o., pp. 95-129.

Summary (Chapter 1: Climate Change Impacts on Forests):

Forests contain a wide range of species with complex life cycles. Forests, particularly in the tropics, harbor as much as two-thirds of the world's biodiversity. They directly affect climate up to the continental scale by influencing ground temperatures, evapotranspiration, surface roughness, albedo, cloud formation, and precipitation. These ecosystems contain 80% of all aboveground carbon in vegetation and about 40% of all soil carbon. Forests and forest soils play a major role in the carbon cycle as sources (e.g., forest degradation and deforestation) and sinks (reforestation, afforestation, and possibly enhanced growth resulting from carbon dioxide fertilization).

Models project that a sustained increase of 1 degree C in global mean temperature is sufficient to cause changes in regional climates that will affect the growth and regeneration capacity of forests in many regions. In several instances, this will alter the function and composition of forests significantly. As a consequence of possible changes in temperature and water availability under doubled equivalent-carbon dioxide equilibrium conditions, a substantial fraction (a global average of one-third, varying by region from one-seventh to two-thirds) of the existing forested area of the world will undergo major changes in broad vegetation types-with the greatest changes occurring in high latitudes and the least in the tropics. Climate change is expected to occur at a rapid rate relative to the speed at which forest species can grow, reproduce, and reestablish themselves at new locations. Although net primary productivity could increase, the standing biomass of forests may not because of more frequent outbreaks and extended ranges of pests and pathogens, and increasing frequency and intensity of fires. Large amounts of carbon could be released into the atmosphere during transitions from one forest type to another because the rate at which carbon can be lost during times of high forest mortality is greater than the rate at which it can be gained through growth to maturity.

Climate change is likely to have its most significant impact on boreal forests through loss of the southern boreal forests, slow invasion of northern treelines into tundra areas, increased fire frequency, and pest outbreaks. The potential area for temperate forests is projected to change the least, but some existing forests, especially in dry regions, will undergo significant changes in species composition. Tropical forests are likely to be more affected by changes in land use than by climate change as long as deforestation continues at its current rate; the greatest effect of climate change on tropical forests is likely to result from changes in soil water availability.

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