中国灰水足迹时空动态演进及驱动因素研究

Study on the Spatial and Temporal Dynamic Evolution and Driving Factors of Grey Water Footprint in China

灰水足迹可从水量角度评价水环境污染程度,有助于实现水污染对水资源短缺影响的评估。中国是全球灰水足迹最大的国家,对中国灰水足迹进行全面准确核算,分析其时空动态演进特征,并准确识别其驱动因素,对缓解中国水资源短缺具有重要意义。从农业(包括种植业和畜牧业)、工业及生活三方面全面计算2011-2021年中国31个省(市、自治区,不含港澳台)的灰水足迹,采用ArcGIS空间制图、核密度估计和标准差椭圆方法分析灰水足迹时空变化特征和动态演进趋势,采用广义迪氏指数分解法探索中国灰水足迹时空动态演进的驱动因素。结果显示,1)2011-2021年中国灰水足迹及其组成均呈下降趋势,工业灰水足迹下降的比例远大于农业灰水足迹和生活灰水足迹;除西藏、青海和新疆的灰水足迹实现了增长外,其余省域的灰水足迹均呈下降趋势,且各省灰水足迹及其组成的区域差异呈缩小态势。2)河南、山东和四川的灰水足迹一直位于全国前3位,而北京、天津、上海和海南均位于全国末位;灰水足迹标准差椭圆均呈现明显的“东北-西南”分布格局,且重心略微向西移动,中国灰水足迹的总体空间分布变化较小。3)GDP和人口数一直为中国及各省灰水足迹的正向驱动因素,而灰水足迹强度、人均灰水足迹和技术效应一直为灰水足迹的负向驱动因素;GDP对灰水足迹增长的促进作用最大,灰水足迹强度对灰水足迹的降低作用最大。研究结果可为中国及各省域制定针对性水污染管理措施提供科学参考。

The grey water footprint enables the assessment of water environmental pollution in terms of water quantity,thereby facilitating the evaluation of the impact of water pollution on water resource scarcity.China possesses the largest grey water footprint globally.It is crucial to mitigate water resource shortages in China,by measuring China’s grey water footprint comprehensively and accurately,analyzing its spatiotemporal dynamic evolution characteristics,and identifying its driving forces precisely.This study comprehensively calculated the grey water footprint of 31 provinces(cities,autonomous regions,excluding Hong Kong,Macao and Taiwan)in China from 2011-2021 across three sectors:agriculture(including planting and animal husbandry),industry and domestic use.ArcGIS spatial mapping,kernel density estimation and standard deviation ellipse methods were used to analyze the temporal and spatial variation characteristics and dynamic evolution trend of grey water footprint.Additionally,the generalized divisia index method was used to explore the driving force of the temporal and spatial dynamic evolution of grey water footprint in China.The results showed that 1)China’s grey water footprint and its composition exhibited a declining trend from 2011 to 2021,with the industrial grey water footprint decreasing at a significantly higher rate compared to the agricultural and domestic sectors.Except for Xizang,Qinghai and Xinjiang,the grey water footprint of the rest of the provinces showed a downward trend,and the regional differences in the grey water footprint and its composition of the provinces showed a narrowing trend.2)The grey water footprint of Henan,Shandong,and Sichuan ranked top three in China,while Beijing,Tianjin,Shanghai,and Hainan ranked at the lower end.The standard deviation ellipses of grey water footprint showed a clear“northeast southwest”distribution pattern,with the center of gravity slightly moving westward.The overall spatial distribution of grey water footprint in China showed little change.3)GDP and population were positive driving factors of the grey water footprint in China and various provinces.However,the intensity of grey water footprint,per capita grey water footprint,and technological effects were negative driving factors of these footprints.In addition,GDP exerted the greatest promoting effect on their growth while the intensity of grey water footprint played an essential role in reducing them.The research outcomes could provide valuable scientific insights to formulate targeted measures,aiming at water pollution management across different regions within China.