Application of agrometeorological spectral model in rice area in southern Brazil

摘要

The southern region is responsable for 70% of rice production in Brazil. In this study, rice areas of Rio Grande do Sul were selected, using the land use classification, scale 1: 100,000, provided by Brazilian Institute of Geography and Statistics (IBGE). MODIS Images were used and meteorological data, available by National Institute of Meteorology (INMET). The period of analysis was crop season 2011/2012, October to march. To obtain evapotranspiration was applied agrometeorological-spectral model SAFER (Simple Algorithm For Retrieving Evapotranspiration). From the analysis of the results, on planting and cultivation period , the average evapotranspiration (ET) daily was 1.93 ± 0.96 mm.day-1. In the vegetative development period of rice, the daily ET has achieved 4.94 mm.day-1, with average value 2,31± 0.97 mm.day-1. In the period of harvest, evapotranspiration daily average was 1.84 ± 0.80 mm.day-1. From results obtained, the estimation of evapotranspiration from satellite images may assist in monitoring the culture during the cycle, assisting in estimates of water productivity and crop yield.