黑龙港地区自然降水条件下粮食生产潜力研究

黑龙港地区为河北省重要粮食产区，但水资源严重匮乏，其中粮食灌溉是第一用水大户，已造成地下水严重超采。2008年10月～2009年10月在大田条件下，以常规灌溉施肥为对照，采用裂区试验设计，研究了不进行灌溉而只靠自然降水进行小麦和玉米生产时的水分生产潜力及其受肥力影响的变化特征。结果表明：在自然降雨条件下，旱地小麦、玉米及周年的平均产量分别为1719．8kg／hm^2、6404．3kg／hm^2和8124．1kg／hm^2。分别是补灌2水处理的22．45％、65．12％和46．44％；平均WUE分别为0．728kg／m^3、1．161kg／m^2和1．031kg/m^3，分别较补灌2水处理低66．44％、26．66％和42．56％。在旱地小麦和玉米生产中，水分是主要限制因素，仅靠自然降雨时肥料的作用不能充分发挥。对缺水的黑龙港地区来说，没有水就没有粮食安全。

Study on Potential Grain Productivity under Natural Precipitation Condition in Heilonggang Region

Heilonggang region was the important grain producing region in Hebei Province with serious shortage of water resources.The irrigation for grain crops was the No.1 water consumption,which had led to heavy groundwater overexploitation.Using normal irrigation and fertilization as the control,a field experiment was conducted to analyze the effects of natural precipitation without irrigation on the water potential productivity and its variation characteristics with fertility in wheat and maize production from October 2008 to October 2009.The results showed that under the natural precipitation condition,the average yield of wheat,maize and annual total grains were 1 719.8 kg/hm2,6 404.3 kg/hm2 and 8 124.1 kg/hm2,respectively,which were 22.45%,65.12% and 46.44% of those with twice irrigation treatment,respectively.The average water use efficiency of wheat,maize and annual total grains were 0.728 kg/m3、1.161 kg/m3 and 1.031 kg/m3,respectively,which were 66.44%,26.66% and 42.56% lower than those with twice irrigation treatment,respectively.In dry land wheat and maize production,water was the main limiting factor.The fertilizer efficiency could not be fully played with natural precipitation only.In Heilonggang region,no water,no grain safety.