Pollution Essay: Forests Counter-Act Global Warming

An important ecosystem service provided by forests is the ability to counter-act the effects of global warming. Carbon dioxide, a contributing factor to global warming, is taken up by the plants and vegetation contained in forests through photosynthesis and the resulting carbon is stored in both living and dead plant biomass. This process, known as carbon sequestration, greatly reduces the potential for global climate change (IPCC 2001). Forest cover also affects the albedo, that is, the proportion of incident solar radiation that is reflected by the earths surface. The dense green coloured canopy of tropical forests have a low albedo when compared with grasslands or deforested areas. This allows for more incident solar radiation to be absorbed and cooler air termperatures (O’Brien 1996).

Perhaps the most important ecosystem service provided by forests, which is a basic requirement for life, is the supply of clean water. Forests facilitate the storage of clean water through filtering precipitation through the tree canopy. This, in effect, slows the rate at which precipitation collects at the ground surface allowing it to remain unsaturated. It is estimated that over 2/3 of the clean water supply is United States is contained within stream water, which was filtered through forests, with a direct value exceeding $27 billion per year (Snail 2009). This clean water can be captured and stored in watersheds that in turn, can be used for variety of purposes including agriculture, municipal drinking water, recreational activities and habitat for wildlife.

Global forests provide habitat for wildlife, which in turn, contribute to the maintenance of ecological processes. Wildlife is directly utilized by humans for hunting, observation and ecotourism. However wildlife is considered an important ecosystem service because of its indirect contribution to many other ecological processes. Wildlife plays an important role in the pollination and seed dispersal of crops. Eighty percent of the world 1,330 cultivated crop species are pollinated by wild pollinators who typically live in forested regions (Abroamorvitz 1997). Additionally wildlife plays an important role in biologically controlling pest populations, specifically in timber species (Snail 2009).

Works Cited

Wiersum, K.F. 1984. Surface erosion under various tropical agroforestry systems. In: O’Loughlin, C.L. and

Pearce, A.J. (eds.) Proceedings Symposium on Effects of Forest Land Use on Erosion and Slope Stability.