河北省主要农作物2005～2014年灰水足迹变化

为了定量分析河北省农业过量施用化肥造成的严重面源污染，应用灰水足迹理论与评价方法，对河北省2005～2014年期间的冬小麦、夏玉米、蔬菜、水果4种主要农作物总灰水足迹及生长过程灰水足迹变化进行了分析评价，结果表明：2005～2014年期间，河北省冬小麦总灰水足迹总体呈下降趋势；夏玉米总灰水足迹总体呈增加趋势；蔬菜总灰水足迹总体呈增加趋势；水果总灰水足迹总体呈下降趋势。2005～2014年期间，河北省冬小麦、夏玉米、蔬菜、水果生长过程灰水足迹均呈下降趋势。4种作物每公顷施肥量没有表现出下降趋势，产量增加是导致4种作物生长过程灰水足迹下降的主要原因。最后从技术和政策两方面提出了降低氮肥施量和作物生长过程灰水足迹的措施。

Variation of grey water footprint of main crops in Hebei Province from 2005 to 2014

In order to quantitatively analyze the serious non-point source pollution caused by the excessive use of chemical compound fertilizer in agriculture in Hebei Province，both the total grey water footprint of four kinds of main crops，i.e.winter wheat，summer corn，vegetables and fruits，and the variation of the grey water footprint during the growing process of the crops are analyzed and evaluated with the relevant theory of grey water footprint and evaluation method. The result shows that in Hebei Province，the total grey water footprint of winter wheat generally presents a decreasing trend，the total grey water footprint of summer corn generally presents an increasing trend，the total grey water footprint of vegetables generally presents an increasing trend and the total grey water footprint of fruits generally presents a decreasing trend during the period of 2005~2014.In this period，all the grey water footprints of winter wheat，summer corn，vegetables and fruits in Hebei Province during their growing processes show the decreasing tendencies. No decreasing trend of fertilizing amount per ha. is there for the four corps，and then the main causation of the decrease of the grey water footprint of the four crops is just the increase of the yield of the crops. Finally，the measures to lower the application of nitrogen-fertilizer and the grey water footprint of the four crops during their growing processes are proposed from the aspects of technology and the policy concerned.