Deforestation and Forest Degradation: The Case of the Islamic Republic of Iran
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recreation is estimated based on the cost of travel to visit forests, had deforestation not occurred. In other cases, the data are so scarce that even cost-based methods cannot be used; whenever meaningful, we use benefit transfer of results from other studies undertaken in similar contexts. In other cases still, relevant information is not available at all, thus valuation of particular benefits cannot be provided.
Costs of Deforestation and Forest Degradation The chapter estimates the gross losses of deforestation and forest degradation without considering the possible benefits of the alternative land uses that replace forests. It estimates the present value of the present and future annual flows of damages due to deforestation and forest degradation that occurred during 2002 and refers these values to that baseline year. It uses a discount rate of 4 percent over a time horizon of 25 years. The selected time horizon is identified with a generation life span, under the assumption that a person of average age would enjoy the benefits of the environment for another 25 years, until death.6 The analysis uses secondary data, mostly from local sources. In the absence of secondary data, whenever meaningful, available information from international sources is used. The analysis involves several uncertainties but suffers from information too limited to address them. Two major issues are (a) the extent of the forest benefit losses and (b) the time for forests to recover, if they do. The extent of losses can be complete or partial, depending on how the deforestation is performed. For example, the slash-and-burn conversion of forest land to agricultural use is likely to cause a complete loss of most (if not all) forest benefits. However, if deforestation means cutting trees for timber, it may cause only a partial loss of some benefits, such as extractive uses relying on forest soil and the remaining vegetation cover (for example, fodder for grazing and other plants) and forest services (for example, watershed protection). Because of the limited knowledge concerning the magnitude of losses caused by deforestation, this chapter attempts to incorporate these valuation issues by using realistic assumptions, to the extent possible given the severe data limitations.
Costs of Deforestation: Direct Use Values This section estimates losses of direct use values grouped in five categories: timber, firewood, grazing and other tangible NWFPs, hunting, and recreation.