Geographia Polonica (1999) vol. 72, iss. 2
Assessment of the importance of forests in reducing global climatic change (counteracting and mitigating the impacts of greenhouse gases)
Geographia Polonica (1999) vol. 72, iss. 2, pp. 27-44
Forests can contribute to increases in atmospheric levels of greenhouse gases (deforestation, bad harvest), are affected by changes in climate (change of natural range of forest tree species) and at the same time offer a unique opportunity to help mitigate future climate change. Forests contribute to the fight against the greenhouse effect in three ways: (1) carbon sequestering; (2) CO2 avoidance through substitution by wood of energy-intensive materials such as plastics, aluminium, steal, cement and brick, (3) CO2 avoidance by using timber instead of fossil fuels for generating energy. The effect of utilization of wood is even greater than that of fixation. Carbon storage would be optimized in plantation forests (refore-station and afforestation), harvested at the time of maximum mean annual increment, when the lifetime of the products exceeds the rotation period. The rate of carbon absorption by trees and forests is a function of growth and age - the rate is higher when they are fast-growing and young. There are some possibilities to increase the carbon accumulation ability of our forests: reconstruction of stands into ones of more adequate species composition; tending of the forest and to the creating of an opportunity to obtain so-called "thinning-induced incre-ment"; the introduction of an understorey which could result in a increment in standing volume; the increase in the fraction of humus in forest soils which could be regulated by means of a preference for the forest regeneration model; resignation from clear-cutting and the afforesta-tion of abandoned agricultural land. The role of Polish forests in reducing global change is not so important as far as the proportional contribution to world forest cover is concerned (0,002%) but from the domestic point of view and in the light of the obligation under the Kyoto Protocol, forest, forestry and wood utilization present a high interest for our environmental policy and an important element in the national development strategy into the 21st century.
, Forest Research Institute, Department of Ecology and Environmental Protection, Sekocin Las, 09-090 Raszyn, Poland