Estimating the agricultural water productivity of the yellow river basin based on remote sensing data

Water shortage for agricultural water use is a major problem m the Yellow River basin. I his research use NDVI value, meteorological data, supervised classification in remote sensing image and actual statistical data to estimate and verify the wheat and maize distribution and the relevant crop water productivity values in the Yellow River basin. The validation of the method is performed by comparing the results with the distribution of CIESIN statistic data for 1990. To obtain the accurate crop water productivity, the study used and compared two methods for calculating the total crop water productivity. The first one is to sum the crop water productivity calculated by multiplying the crop water requirement per unit area and the estimated planting total area of crops in the basin. The second one is to sum the crop water productivity calculated for each province. The research found that the remote sensing data could efficiently improve the accuracy in estimating the crop water productivity.