中国粮食生产的水资源利用特征评价

基于标准彭曼公式，利用CROPWAT软件测量了中国31个省区粮食作物的绿水、蓝水及灰水足迹，并在此基础上对粮食生产的耗水量、生态修复需水量以及水资源利用效率进行了评价。结果显示：小麦、玉米和水稻三种粮食作物对水资源的消耗数量和类型存在较大地区差异，河南、山东等省份具有较高的水资源使用量，而浙江、福建等省份用于粮食生产的水资源数量相对较少，江苏、浙江等降雨量充沛的省份具有相对较高的绿水消耗比重，而陕西、甘肃等水资源稀缺省份具有较高的蓝水消耗比重；1998-2013年三种粮食作物的灰水足迹总量均在总体上呈现出上升趋势，其中水稻的灰水足迹总量相对最高，灰水足迹总量较大的地区主要集中于东北、华北、华东、华中等区域，表明这些地区对生态修复水量的需求较大；我国粮食作物的水足迹强度在总体上呈现出下降趋势，表明水资源利用效率得到了提高，空间分析结果显示水足迹强度具有显著的全局与局域空间正相关特征，其中相比于西北和华北地区，西南、华东和华南地区具有相对较低的水足迹强度，意味着这些地区具有较高的水资源利用效率。

Evaluation on Utilization of Water Resources of Food Production in China

Based on Penman-Monteith Equation,this paper measures the green water footprint,blue water footprint and grey water footprint of food crop in 31 provinces of China by using CROPWAT software,and then evaluates water consumption,water demand for ecological restoration and water use efficiency of food production.The result shows that firstly,there are significant regional differences of water quantity and type consumed by wheat,maize and rice.Henan and Shandong provinces have high water consumption for food production,and Zhejiang and Fujian provinces have relatively low water consumption.In addition,the provinces with abundant precipitation,such as Jiangsu and Zhejiang,have a higher proportion of green water consumption in the total water use,while provinces such as Shaanxi and Gansu,which are short of water resources,have a high proportion of blue water consumption in the total water use.Secondly,the amount of grey water footprint of food crop has a rising trend on the whole between 1998 and 2013,and the amount of grey water footprint of rice is the highest among the three crops.Specifically,the areas with large amount of grey water footprint are mainly located in northeastern China,northern China,eastern China and central China,which shows that these areas have a greater water demand for environmental restoration.Finally,water footprint intensity of food crop has a downward trend in recent years,which indicates that water use efficiency is improving.In addition,the results of spatial analysis show that water footprint intensity has a significant global and local positive spatial autocorrelation.Specifically,compared with northwestern and northern China,the areas of southwest China,eastern China and southern China have relatively lower water footprint intensity,and this indicates water use efficiency in these areas is relatively higher.