黄河流域小麦生产水足迹量化与评价

Water Footprint Accounting and Evaluation for Wheat Production in Yellow River Basin

摘要:

为准确评价区域不同时空尺度作物生产耗水量及耗水效率的动态变化及其分布规律，以黄河流域典型年为例，基于作物水分生产力模型AquaCrop，考虑不同供水和灌溉方式，在5′空间尺度对流域内小麦生产水足迹进行了量化与评价。结果表明：流域小麦水足迹总量和单位生产水足迹年均值分别为2.19×1010m3和1.22m3/kg，蓝水足迹占65%，单位生产水足迹呈现上游向下游递减的趋势。传统地面灌农田小麦生产蓝、绿水足迹量分别为流域总量的92%和50%。流域灌溉条件下小麦生产水足迹（1.40m3/kg）高于雨养条件（1.12m3/kg）；灌溉方式对小麦生产水足迹影响显著，其中微灌仅为1.67m3/kg，喷灌条件下高达2.07m3/kg。供水与灌溉方式对区域农作物生产水足迹的影响不可忽略，考虑不同供水与灌溉方式的作物生产水足迹量化与评价将成为农业水资源高效利用的重要基础。研究结果可为不同时空尺度农作物水足迹核算和区域农业节水策略制定提供参考。

Abstract:

In order to accurately evaluate the dynamic changes and distribution in water consumption quantity and efficiency of crop production at different spatial and temporal scales in a region, the AquaCrop model was applied at 5′ spatial resolution to estimate the blue and green water footprints (WFs) of wheat production in three typical hydrological typical years in Yellow River Basin (YRB). Irrigated and rainfed wheat were identified. Results showed that the annual average total WF and perunitproduct WF of wheat in YRB were 2.19×1010m3 and 1.22m3/kg, respectively. Blue WF accounted for 65% of the perunitproduct WF of wheat. The wheat WF was decreased from the upper reach to the lower reach in YRB. Traditional surface irrigation dominated the total blue WF and total green WF of wheat by occupying 92% and 50% of basin’s total amount, respectively. The WF under irrigated condition was 1.40m3/kg, which was higher than that under rainfed condition of 1.12m3/kg. The WF of wheat production in YRB was affected by irrigation methods. The basin average WF under micro irrigation was only 1.67m3/kg, while that of sprinkler irrigation was up to 2.07m3/kg. The result indicated that the effects of different water supply and irrigation methods on large-scale WF accounting can not be ignored. The quantification and evaluation of crop WF distinguishing different water supply and irrigation methods could be an important foundation for efficient utilization of agricultural water resources. The results can provide reference for WF accounting and regional agricultural water saving strategy formulated for different temporal and spatial scales.