Estimation of Chlorophyll in Irrigated Wheat by Aster High Resolution Satellite Imagery（Extracts）

Identifying crop properties non-destructively can provide a rapid and accurate understanding of its response to various environmental influences.Crop chlorophyll content is an important indicator of crop health and therefore estimation of crop yield.In recent years，remote sensing has been accepted as a robust tool for site-specific management by detecting crop parameters at both local and large scales.The reported research assessed the potential of high resolution satellite imagery to predict wheat properties at a regional scale.Vegetation indices including NDVI，RVI，GNDVIbr and other band ratios，were derived from ASTER imagery and related to crop chlorophyll concentration.The results demonstrated the effectiveness of using ASTER high resolution satellite images to map spatial variation of wheat chlorophyll content through the derived vegetation indices.NDVI and redgreen band ratio were revealed to be sensitive indices for assessing wheat chlorophyll content （R=0.73 and 0.72 respectively）.The results suggested that use of high spatial resolution satellite imagery for the retrieval of crop chlorophyll levels provides an effective assessment of crop status at a regional scale.