Philip Fearnside is at the Dept of Ecology, National Institute for Research in the Amazon (INPA), CP 478, 69.011 Manaus-Amazonas, Brazil.
Trends Ecol Evol. 1990 Jun;5(6):192-6. doi: 10.1016/0169-5347(90)90209-V.
Tropical rainiorest areas are rapidly being settled as a result of continued growth of local populations, spontaneous migration from non-rainiorest areas and planned settlement projects undertaken by governments. National decision makers frequently view rainiorest settlement as a solution to the problems of other regions undergoing population growth, land tenure concentration, environmental degradation, agricultural mechanization and population displacement by development projects. Natural habitats are replaced by settlements that often cannot support the density of population expected of them. Inappropriate assumptions can lead to estimates that are orders of magnitude too high, such as an FAO calculation that Brazil could support over seven billion people if Amazonia were converted to intensive agriculture. Inadequate information on human carrying capacity allows planners to foster unrealistic expectations.
由于当地人口的持续增长、非雨林地区的自发性迁移以及政府的计划定居项目，热带雨林地区正在迅速被定居。国家决策者经常将雨林定居视为解决其他地区人口增长、土地保有权集中、环境退化、农业机械化和发展项目导致人口流离失所等问题的一种方法。自然栖息地被定居点所取代，这些定居点往往无法支撑预期的人口密度。不恰当的假设可能导致估计值高出几个数量级，例如粮农组织的一项计算表明，如果将亚马逊地区转变为集约化农业，巴西可以容纳超过 70 亿人口。对人类承载能力的信息不足使得规划者产生了不切实际的期望。
