HUMAN CARRYING-CAPACITY ESTIMATION IN BRAZILIAN AMAZONIA AS A BASIS FOR SUSTAINABLE DEVELOPMENT

Sustainable development requires that population and consumption remai n within the limits of carrying capacity, while preventing a decline i n the carrying capacity of an area requires that productive systems im planted through development be sustainable. Zoning can be a valuable t ool in influencing land-use decisions, but we cannot expect government decrees to be capable of causing the landscape to evolve toward the s ustainable patterns which have been recommended through zoning. A prer equisite for influencing land-use change is understanding the social p rocesses involved in land-use decisions, beginning with deforestation dynamics. Work to estimate carrying capacity needs to embrace the wide variety of production systems used and contemplated for Amazonia and to be able to interpret this information at scales ranging from local communities to the region as a whole. This will require not only studi es of different land-use systems in rural areas, but also integration with studies of energy use and support limits of urban populations. Ri sks of environmental impacts must be quantified under different develo pment scenarios, and limits of acceptable risk identified and integrat ed into analyses of carrying capacity. Tapping the value of environmen tal services of standing forest represents a promising means of sustai ning Amazonia's population over the long term, but numerous obstacles exist. These include halting deforestation before opportunities are lo st and supporting the population in non-damaging ways while the instit utional groundwork is laid for using the environmental services involv ed. Research is needed to quantify the magnitude of services and the a ppropriate monetary value per unit of service. Diplomatic agreement mu st be reached on these values, which can be expected to be quite diffe rent from estimates of the 'true' values based on research. A series o f social arrangements must be proposed and implemented if the value de rived from environmental services is to fulfil its dual role of mainta ining both the forest and the human population in Amazonia.