Diversidade de espécies aumenta a renda em sistemas agroflorestais na Amazônia Oriental

Abstract

This study compares biodiversity and socioeconomic performance of a wide range of agroforestry systems. We quantified (i) agroforestry species diversity (commercial, subsistence and „non-productive‟ species), and (ii) key socioeconomic variables (costs, monetary and non-monetary income, net income, degree of satisfaction) in 38 farms, aggregated in 4 site-clusters in the eastern periphery of Amazonia. We cover a wide range of agroforestry systems, ranging from commercial to subsistence, and from simply-structured plantations developed by Japanese immigrants to complex and biodiverse systems (enriched fallows and multi-strata homegardens), and compare these with the region´s two predominating landuse systems, pastures with babassu palms (dominating in area) and slash-and-burn shifting cultivation (dominating in people). Landuse-intensity (costs and income per hectare) were highest in commercial plantation agroforestry and in subsistence homegardens, and lowest in enriched fallows and pastures. All agroforestry systems resulted in higher income:cost ratios and a higher degree of satisfaction than pastures and shifting cultivation. Non-monetary income and the income:cost ratio were highest in small homegardens, a system which so far lacks systematic Research & Development and extension efforts. Total species richness was negatively related both with costs and monetary, but not with non-monetary income per hectare, due to occupation of space by „non-productive‟ species which provide important ecosystem services. The number of productive species was positively related to (mainly non-monetary) income, net-income and especially the income:cost ratio. Future efforts for food security and poverty reduction need to focus more on species rich agroforestry systems, notably the ubiquitary and successful homegardens