渭北旱塬麦田水分循环及水分亏缺研究

Studies on Hydrologic Cycle and Water stress of Wheat Field in Weibei Arid Highland

渭北旱塬麦田土壤水分支出的主要途径是蒸散作用，收入则靠降水。经在本区的永寿县民丰村定点定位采用仪器观测，所取结果用平衡公式计算，麦田水分的收支基本入不敷出（降水量－麦田蒸散量）。因此，干旱缺水是该区小麦生产的主要限制因素，因而抗旱保墒也就成为当地小麦增产的主要措施之一。

The evapotranspiration is the main reason to cause the soil moisture evaporation in thewheat field,and the absorption is related to the precipitation in Weibei Arid Highland.The sttidiesof observing definite spots by instruments in Minfeng village,Yongshou county in this area showthat the amount of soil moisttire absorption in the wheat field is less than that of evaporation(thedifference between precipitation and evaporation in the wheat field).And all the results obtainedwere calculated by the method of balance formula. It is obvious that drought resistance and soilmoisture conservation is oiie of the main measures for increasing wheat yield in Weibei Arid High-land because both of drought and water stress in the soil are the major limiting factors of wheatyield.