基于流域的陕西省水资源承载力研究

Water resource carrying capacity in Shaanxi Province at the scales of watersheds

以陕西省9个流域为评价单元,基于宏观指标和综合指标构建水资源承载力综合评价模型。通过分析经济压力、人口压力、承载压力及协调指数,进而对研究区水资源承载力进行评价并探讨其时空分布特征。结果表明:(1)陕西各流域水资源承载力差异较为明显,其中陕南最大,陕北次之,汉中最小。陕南地区的汉江和嘉陵江两个流域水资源丰富且降水充足,WI<0.6处于承载适宜阶段,但该流域水资源利用效率较低HI<0.6,流域人均用水量、万元GDP用水量以及农田灌溉亩均用水量均超过全省平均水平。陕北地区的河口-龙门、内流区以及北洛河三个流域水资源紧缺且存在水质性缺水问题,处于轻度超载阶段;而关中地区的渭河、泾河、龙门三门峡及伊洛河四个流域水资源供需矛盾随着人口与经济的增长进一步加剧,水资源承载力综合评价指标值WI>1.5,处于严重超载阶段。(2)从承载压力指数分析可以看出,流域调水对缺水地区或经济中心城市的发展起到决定性作用。从丰水流域跨流域调水能解决地区性缺水问题,进而解决水资源危机所带来的社会经济可持续发展问题。(3)基于水资源的自然资源属性,以流域为评价单元,其研究结果更符合自然规律,有利于实现流域间水资源的合理均衡和分配。

Water resource carrying capacity is a critical index that is used to measure sustainable social and economic development in the arid and semi-arid regions.Taking nine basins of Shaanxi Province,China as evaluation units,this paper constructed a comprehensive evaluation model of water resource carrying capacity from two aspects of the macro index and comprehensive index,respectively,to reflect the size,carrying status,and coordination status of water resources carrying capacity.Macro index refers to the economic pressure index and the population pressure index.The comprehensive index refers to the carrying pressure index and the coordination index,which are calculated by constructing an index system that covers water resource,socio-economic and ecological indexes.Finally,through the analysis of the economic pressure index,population pressure index,carrying pressure index,and coordination index,this paper evaluates and discusses the water resource carrying capacity and the spatio-temporal distribution characteristics of various basins in Shaanxi Province.The results showed as follows:(1)the water resource of various basins in Shaanxi Province are unevenly distributed and water resource carrying capacity varies significantly,being maximum in southern Shaanxi and minimum in northern Shaanxi and Guanzhong.The Hanjiang River and Jialing River basins in southern Shaanxi are rich in water and rich in precipitation,and the water resource carrying capacity(WI<0.6)is in a suitable state.However,the water resource utilization efficiency in these two basins is relatively low(HI<0.6),and the water consumption per capita,per ten thousand Yuan of GDP,and per mu of farmland irrigation were all higher than the provincial average.Water scarcity and water quality issues threaten the basins of Hekou-Longmen,interior drainage area,and Beiluo River in northen Shaanxi(1.20<WI<1.50).In addition,the water resource carrying capacity is in a state of mild overload.With population and economic growth,the four river basins of the Weihe River,Jing River,Longmen-Sanmenxia,and Yiluo River in Guanzhong region have problems on water supply and demand.Although these resources account for 61.75%of the provincial population theoretically,they can only serve 18.52%of the total province.The comprehensive evaluation index value of water resource carrying capacity is greater than 1.5,which is in a severe overload state.(2)from the analysis of carrying pressure index,it can be seen that the inter-basin water transfers play a decisive role in the development of water-deficient areas and economic centers.As can be seen from Figure 2,the water consumption of the three basins in the Guanzhong region is greater than their total water resources.In other words,inter-basin water transfers from water-rich basins can solve the regional water shortage problem,and then solve the socio-economic issues of sustainable development caused by water crisis.(3)based on the natural resource attributes of water resources,the results of research conducted on the basin,as an evaluation unit,were essentially in line with the laws of nature,contributing to the realization of rational balance and distribution of water resources.