京津冀地区水资源供需平衡及其水资源承载力

A Study on Water Resources Carrying Capacity in Jingjinji Region

京津冀地区丰水年可实现水资源供需平衡;平水年以下,水资源供需矛盾突出;即使降水偏丰年份,京津地区依然供不应求;水资源短缺已成为影响京津冀地区21世纪经济社会可持续发展的主要制约因素。在区域水资源供需平衡分析的基础上,应用“承载人口数”方法定量研究了京津冀地区不同生活水平、不同水平年下水资源所能承载的人口数量与经济发展规模。研究表明:在平水年(p=50%)以上,按温饱标准,水资源承载能力高于现状人口,但是按小康标准,水资源支撑的经济指标无法实现;发达地区遇到枯水年时,可以通过降低福利标准提升水资源承载力,但对于部分欠发达地区,遇到枯水年时,福利标准已经很低,可能会出现水危机。南水北调实施以后,京津冀地区水资源承载力有所提升,但由于人口的增长,社会福利水平并没有显著提高。因此,解决京津冀水资源短缺问题,不能只谈调水和节水,还需防止人口过度膨胀,否则,南水北调成果有可能被过度的人口所吞噬。

China is one of the countries facing the most serious water shortage crisis.In recent years,the water problem has become more and more projecting,especially for urban area where water shortage has been a common problem--water demand is mounting up rapidly due to population burgeon and improvement of living people＇s standards.The serious dearth of water has turned out to be a bottleneck in the region＇s social and economic development,which makes the research on water resource more pressing.In this paper,we mainly study the water resources carrying capacity （WRCC）,as the groundwork of the study of water resources security stratagem, which plays an important role in the harmonious development of regional water-ecology-socioeconomy complex system.Jingjinji region located in the Hvihe River valley is chosen as a typical area to study the water shortage problem.This region includes Beijing,Tianjin and eight cities in Heibei province：Shijiazhuang,Tangshan,Qinhuangdao,Baoding,Zhangjiakou,Chengde,C angzhou and Langfang,which is around Greater Beijing Economic Hub and is the core area of the Bohai Bay Trade Hub.Mean while it is severely short of water resources,the average water resources of which is only 370×10^8m^3,1.3% less than the national average level,but it carries about 10% ofthe national population,food and GDP. A model of water resources is developed for analyzing the carrying capacity of water resources in different years in this region.The model for calculating WRCC is established by taking the “population capacity capacity” as its synthetic index and using the system optimization method.And a formula of load factors is also used to compute the potential of water resources in different areas. The final results indicate that：l）There are still 684×10^8m^3 of potential water resources which come from rain and flood in the region,and could be exploited.2）In the years of normal precipitation （p=50%）,according to the “having enough to eat and wear” life standard,the population that water resources can carry is larger than that of nowadays;while,if according to the “better-off”life standard,the water resources cannot support today＇s population.3）In drought years,in developed area, the population can be carried by lowering the living standard ,however, in underdeveloped areas,when having a long-term drought,the population cannot be supported.4） Although the water carrying capacity of Jingjinji region may be improved after completing the South to North Water Transfer Project,the living standard might not be improved,for it can be offset by the increasing population.So,the rudimentary method for solving the problem of water scarcity is stringent population control.