Análise prospectiva da distribuição da soja no estado do Tocantins, considerando-se cenários de mudanças climáticas

Abstract

ABSTRACT Soybean is one of the agroenergy crops of greatest supply and demand in the Brazilian economy. Even though positive slopes in the productivity curves are constantly perceptible, the demands for arable land are evolving wildly, inevitably promoting deforestation actions and deleterious effects on the natural biogeochemical cycles, such as the carbon cycle. Several environmental models are used to explain these complex phenomena, whose variables change spatially and temporally as a function of economic, social and natural factors. Therefore, this study aimed at prospecting the soybean cultivation area using a territorial dynamics model (Dinamica EGO), in regions where sustainable use conservation units are located in the Tocantins state, considering different climate risk scenarios based on the water requirement satisfaction indexes (WRSI), calculated using daily average rainfall and temperature data from the MIROC5 global climate model. The WRSI contributed to a greater exploitation of natural resources around the environmental preservation areas of Ilha do Bananal/ Cantão, Lago de Palmas and Serra do Lajeado. Furthermore, a possible decrease in the soybean area in some recognized producing centers was prospected, as well as a scenario of greater distancing of this species cultivated areas, in a near future, from the mosaic of conservation units of Jalapão, which has become of high climatic risk for the soybean grain yields usually demanded by the market.