The working paper compares the 1990 net forest areas and the figures for net annual forest area change derived from FRA 1990 and FRA 2000.
The total 1990 forest area registered by FRA 2000 was found to be 521 million ha or 15.1% larger than the corresponding figure from FRA 1990. This difference owes primarily to change of definitions of forest between the assessments (in particular the lowering of the threshold value for crown density in the industrialized countries from 20 to 10%). The change of forest definitions had the largest impact on the reported forest areas for Australia and the Former USSR.
Due to the above, a larger forest area was studied in FRA 2000 compared to FRA 1990. Despite that, the net annual forest area change during the 1990's reported for FRA 2000 was - 9.4 million ha, representing a positive development from the FRA 1990 estimate of - 13.1 million ha during the 1980's. The rate of net forest area loss as reported by FRA has thereby decreased by 3.7 million ha from the 1980's to the 1990s. If the FRA 1990 definitions are applied to the data for the 1990s, the slowing net deforestation trend at the global level is further enhanced.
The FRA 2000 regional data were adjusted for anticipated plantations success rate of 70% and for the results of the FRA 2000 Remote Sensing Survey for Africa. The adjusted data indicate that the main reasons for the reported positive development in forest cover change from the 1980s to the 1990s at global level, are reported increasing forest cover in Europe & North America and in particular a reported slowdown in the rate of deforestation in South America (+2,3 million ha annually). FRA 2000 Remote Sensing Survey was not able to indicate a statistically significant difference between the rates of forest area change during the 1980s and the 1990s for Tropical South America or the other 2 tropical regions.
Changes of methodology, forest definitions, quality and timeliness of underlying data between the assessments however makes a direct calculation of forest cover change based on data from the two assessments problematic. However the results point to a slow down in the global rate of net forest area loss, primarily generated by natural regrowth in the non tropical domain and by a reduced rate of net forest cover loss in South America.
At the same time the global loss of natural forests has continued at roughly the same rate for the past 20 years. The loss of natural forest in the tropical domain remains alarmingly high at approximately 14.2 mill ha. or 1% per annum