石家庄市主要农作物灌溉节水潜力研究

利用田间作物灌溉试验数据，对作物单产产量与需水量的关系进行了模拟，并据此以县域为单元，计算了1984～2001年石家庄市主要农作物冬小麦、夏玉米和棉花获得逐年实际产量的理论总需水量、理论灌溉总需水量、实际灌溉用水量，测算了3种作物灌溉节水的空间。结果表明，1984～2001a。按照节水高效试验所得的产量需水模式。获得石家庄市3种主要作物产量的理论需水总量为23-29亿m^3／a，理论灌溉需水总量为8．8-13．8亿m^3／a，实际灌溉用水量平均约为17亿m^3／a，农业年均超采地下水5．67亿m^3／a。按照目前的种植结构和产量水平，石家庄市今后作物灌溉节水的理论上限为9亿m^3／a。即使加大节水投入，实现最大节水潜力的一半。仍不能弥补目前地下水的超采量。在2010年实现南水北调，部分城市用水归还农业用水，且实现最大节水潜力的一半的情况下，水资源方能勉强维持平衡。因此，石家庄市今后应一方面加大农业节水投入和管理。另一方面，也应根据水资源承载力适当减少高耗水的冬小麦播种面积，同时全面建设节水型社会，方能实现可持续发展。

Study on Irrigation Water-saving Potentiality of the Three Main Crops in Shijiazhuang

Using field irrigation data of the three main crops from 3 stations of Hebei Irrigation Technology Experimenting and Popularizing Center,this paper simulated the relationship between the three main crops'yield and water demand during the growing season.Based on it and taking county as the basic unit,the paper calculated winter wheat,summer corn and cottons' theoretical water demanding volume,theoretical irrigating water demanding volume and practical irrigating water volume of Shijiazhuang from 1984 to 2001.Considering the actual available water resources,the irrigation water-saving potentiality of the three main crops was also evaluated.The result shows that according to the relationship between yield and water demand,getting the three crops' real gross output from 1984 to 2001,the theoretical gross water demanding volume is 2.3 to 2.9 billion m~3 per year,the theoretical irrigating water volume demanded is 0.88 to 1.38 billion m~3 per year,while the practical irrigating water volume can reach 1.7 billion m~3 per year.The ground water over pumping volume is (0.576) billion m~3 per year.With the present crop structure and yield level,the biggest irrigating water-saving potentiality in the future is(0.9) billion m~3 per year.Even if the efforts of water-saving in irrigation is greatly increased and the water-saving rate reaches 50% of the potentiality,the problem of ground water over pumping still exists.After 2010,only when the South to North Water Transport Project finishes,with some water used previously by cities returned to farming and the irrigating water-saving rate reaching 50%,the basic water resources recycling balance can be managed.Therefore,to realize the aim of sustainable agricultural development,efforts to save water in irrigation should be emphasized and management be improved on one hand,and on the other hand,the farming area of high water-consuming crop winter wheat should be reduces according the water resources supporting capacity.Certainly,the construction of a water saving society is urgently needed.