Sistema de previsão de safra de soja para o Brasil.

Abstract

Facing the necessity to estimate the soybean harvest for Brazil through more objective methodology, offering higher credibility to the official harvest data, idea stimulated by the creation of the GeoSafras project, coordinated by CONAB, it was developed a system of soybean harvest forecast for Brazil, based on Agrometeorological Monitoring System - Agritempo. The system incorporates the conceptual bases proposed by DOORENBOS & KASSAM, (1979), adding empirical adjustments for each state using experimental data from Embrapa units from all Brazil, and a database of soybean sown area proceeding from IBGE. Tests were done esteeming the soybean harvest between 2000/01 and the current harvest, 2005/06. Good fittings were gotten for regions harvests, proving it necessity of adjustments mainly for South and Northeast Regions. In national terms, the highest observed error was 5.81% for the 2000/01 harvest, and the smaller, 0.77% for the 2005/06.