changes and elevated wind turbulence cause increased tree mortality. Such edge effects increase exponentially as the area cleared increases linearly. Losses due to edge effect would not be detected by satellite reconnaissance, and probably not even by conventional land-based mapping techniques. Laur-ance and Fearnside (1999) further suggest that losses may be increasing. They stated that "Despite initiatives to reduce deforestation, in 1998 the rate of forest loss in the Brazilian Amazon rose by nearly 30% over the preceding year - not including the extensive areas degraded by ground-fires, logging or habitat fragmentation". Consequently, rates of deforestation may be greater than those reported in Tables 4.1-4.3.

Despite the problems of assigning accurate numbers to deforestation rates and biomass changes, the data suggest regional trends. From 1990-1997 Latin America and Southeast Asia had similar rates of deforestation in terms of area cleared. However, because in Latin America there is a much greater area of moist forest, percentage loss is lower (Table 4.3). The rate of loss in open woodlands of Africa is relatively high, but Africa has considerably more open woodlands than closed forests, and more open woodlands than the other two continents (Table 4.2).

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