黄土高原多沙粗沙区作物水分供需状况评价

采用最大可能蒸散、作物实际蒸散、水分盈亏、水分订正系数评价了黄土高原多沙粗沙区主要作物(春小麦、冬小麦、春玉米、夏玉米和棉花)和草地生长季水分供需状况,结果表明,需水量:冬小麦>棉花>春玉米>春小麦>夏玉米;水分订正系数:春玉米>夏玉米>棉花>春小麦>冬小麦。草地需水量为350～450mm,水分订正系数0.95以上,水分供需矛盾小,实施退耕还牧无论对缓解水资源短缺,还是改善生态环境,在黄土高原多沙粗沙区都是十分有效的措施。

Evaluation on Crop Water Demand and Supply in Plentiful and Coarse Sandy Area in Loess Plateau

The water demand and supply condition of main crops, such as spring wheat, winter wheat, spring maize, summer maize, and cotton, and grassland in the growth stage in the plentiful and coarse sandy area in the Loess Plateau is evaluated with the potential evapotranspiration, actual crop evapotranspiration, water profit and loss, and water correction coefficient. It indicates that the water demand decreases by winter wheat, cotton, spring maize, spring wheat, and summer maize. And the water correction coefficient decreases by spring maize, summer maize, cotton, spring wheat, and winter wheat. Whereas the water demand in the grassland is 350-450mm, and the water correction coefficient is over 0 95, which show that the confliction of water demand and supply in the grassland is lower. Returning farmland to grassland in the region is an effective measure that can ameliorate the water resource shortage and improve the ecological environment.