Padrões econômicos-ambientais da agropecuária no estado do Tocantins: estudo comparativo de microbacias correspondentes a três sistemas agrários relevantes

Abstract

At first it was developed a theoretical basis that supports this work, structuring an environmental sustainability concept, which by its turn props the elaboration of an index of agricultural sustainable environment (ISAGRI). It’s paramount that the referred index is based, among others, in a Universal Equation of soil loss – EUPS. It has been worked also in the analysis of the anthropic action effects practiced by soybean producers, cattleman, and small producers, in three micro bays of Tocantins State located in the municipalities of Sítio Novo do Tocantins, by the State’s north region; Araguaia, northeast; and Pedro Afonso, in the central region of the State. In this analysis, it was calculated the sustainability grade inherent to each of the activities using the ISAGRI. From this reality observed in regions under study it were created multiples alternative scenarios that allowed a higher range to the analysis effectuated according the results shown by ISAGRI. It was compared the acquittal presented by each category among the producers to identify which one produces higher aggressions to environment. The ISAGRI was used also in its disaggregated mode through its sub index which allowed less disaggregation comparators and thereby closer to reality. Than it were made calculations of valuation of replacement costs of soil restoration resulting from the activities of rural producers. To do the calculations it was used the Replacement Cost Method (MCR), with some alterings in the standard model. To the results acquired it was applied the same comparative analysis used before. According the results, regarding the environment sustainable point of view, the cattleman located in the micro bay in the municipality of Araguaia-TO activities are in the same level reached by the small producers of Sitio Novo do Tocantins-TO which means that it is a good standard. However the soybean producers established in the micro bay of Pedro Afonso-TO reached an index considered only as regular. It is possible to observe that when multiple alternative scenarios are analyzed, in some parts they are particularly interesting and in others they are preoccupying, all of them are commented throughout the study. Nevertheless when considered the valuation of the replacement cost of lost soil, operations with small producers, including the projected scenarios are considered non sustainable which generates a situation at some point paradoxical. When, regarding the environmental point of view, its activity reaches a good level of sustainability. And concerning the restitution costs valuation of soil losses by its activities they drop to non sustainability standard. The soybean croppers are in the real conditions, inside the sustainability pattern and according the foreseen scenario, sometimes, are in the sustainable model and sometimes out. In the case of cattleman in all of situations their activities remains in the sustainability context.