咸阳市农田灌溉水有效利用系数测算与分析

Calculation and Analysis of Effective Utilization Coefficient of Farmland Irrigation Water in Xianyang

农田灌溉水有效利用系数是衡量水的利用效率的一项重要指标。为了获得咸阳市农田灌溉水有效利用系数,利用首尾测算法来对咸阳市农田灌溉水有效利用系数进行了测算分析,即通过作物典型田块的每公顷平均净灌溉定额和典型田块的田块面积加权平均,确定片区的作物净灌溉定额,再利用整个灌区作物种植面积和净灌溉定额,确定灌区的年净灌溉用水量。分析了2016年咸阳市40个样点灌区的基本数据,计算出各类型灌区的农田灌溉水有效利用系数。计算表明:咸阳市大型灌区、中型灌区、小型灌区、井灌区农田灌溉水有效利用系数分别为:0.577 7、0.565 0、0.599 0、0.761 3,咸阳市的综合农田灌溉水有效利用系数为0.577 0。结果表明:咸阳市农田灌溉水有效利用系数有很大的提升潜力。提出了测算过程中存在的问题及解决办法,计算成果为提高农田灌溉水有效利用系数的提供了依据。

Irrigation water-using coefficient is one of the most important indexes to measure the coefficient of irrigation water.In this paper,＇head to tail＇ test is used to calculate and analyse the irrigation water-using coefficient in Xianyang city in order to attain the irrigation water-using coefficient in this region.In ＂head to tail＂ test,the plants net irrigation quota on each application in certain distinct is determined by net irrigation quota for unit area in typical fileds and the weighted average area of the filed first,and then the annual irrigation water use is obtained from the plants cultivated area and the net irrigation quota.In this paper,the basic data of 40 sampling irrigation areas in Xianyang is analyzed and the irrigation water-using coefficient in different kinds of irrigation areas is calculated.The results show that the irrigation water-using coefficients of large irrigation areas,medium irrigation areas,small irrigation areas and well irrigation areas in Xianyang are 0.577 7,0.565 0,0.599 0 and 0.761 3,respectively;the comprehensive irrigation water-using coefficient is 0.577 0;there are huge potential in improving irrigation water-using coefficient of Xianyang.Also,some problems and corresponding solutions during the calculation process are pointed out in the paper.The final calculated result provides a technical basis for improving the irrigation water-using coefficient.