The definition and classification of field evapotranspiration was discussed, based on which the calculation model for field evapotranspiration was established. Based on crop, soil measurements and mean climatic data i...The definition and classification of field evapotranspiration was discussed, based on which the calculation model for field evapotranspiration was established. Based on crop, soil measurements and mean climatic data in 1950-1980, mean field water surplus or deficit on climatic, crop and cropland basis in dryland of northern China was calculated, and the pattern of field water surplus or deficit was analyzed and discussed in this paper.展开更多
基金The national key research project: Field water balance and its regulation techniques, water potential productivity and its prope
文摘The definition and classification of field evapotranspiration was discussed, based on which the calculation model for field evapotranspiration was established. Based on crop, soil measurements and mean climatic data in 1950-1980, mean field water surplus or deficit on climatic, crop and cropland basis in dryland of northern China was calculated, and the pattern of field water surplus or deficit was analyzed and discussed in this paper.