Mapeamento da área cultivada e estimativa do rendimento de grãos de arroz irrigado a partir de modelos agrometeorológicos-espectrais para o Rio Grande do Sul / Crop area mapping and crop rice yields estimation using agrometeorological-spectral models for Rio Grande do Sul state, Brazil

AUTOR(ES)
FONTE

IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia

DATA DE PUBLICAÇÃO

2012

RESUMO

The objective of this study was to characterize the irrigated rice crop at Rio Grande do Sul State and to test a methodology to define the cultivated area and to estimate the grain yield through the adjustment of the agrometeorological-spectral models. The study was developed for the six rice-growing regions of Rio Grande do Sul. Data of the irrigated rice grain yield, crop area, meteorological data and NDVI (Normalized Difference of Vegetation Index) images of MODIS (Moderate resolution Imaging Spectroradiometer) sensor, were used from August to April, from 2000/01 to 2009/10 crop season. The results showed that there are accentuated differences between the rice-growing regions of the State related to the agricultural statistics of irrigated rice crop. There are technological increasing tendency of grain yield, at the average State level as well as for the six ricegrowing regions. The proposed methodology to determine the spacial distribution and to quantify the irrigated rice crop areas is efficient, and can be used to provide input data on agrometeorological-spectral models to estimate grain yield. The obtained temporal profiles of NDVI/MODIS are typical of crop areas and are associated to the principal stages of culture development. The NDVI values are low in the implantation period, increasing during the vegetative development, reaching the maximum values at the flowering and at the beginning of the grain filling and decreasing during the grain physiological maturation. The solar radiation, minimum air temperature and NDVI are associated to the irrigated rice grain yield, in several crop development periods. The agrometeorological-spectral models to estimate irrigated rice grain yield, adjusted through at the orientated approach by the climate-plant relationships, are adequate to the estimates in regional levels and can introduce objectivity to the current harvests forecasts. However, the elaborated model for the Rio Grande do Sul as a whole still needs improvements.

ASSUNTO(S)

meteorologia sensoriamento remoto

Documentos Relacionados