Research On The Urban Appropriate Scale In Arid Inland River Basin Based On Water Resource Carrying Capacity

Water is one of the most valuable natural resource for human survival anddevelopment. It lays an extremely important role on urban development and is aprerequisite of the cities’ emergence. Water is also the decisive factor of the cities’sustained economic growth and population capacity. Water shortages and fragileecological environment have become two important factors which restrict the socialand economic development in the northwest arid inland river basin in China. In theprocess of the implementation of western development strategy, speeding up theurbanization process is the inevitable choice to reduce the pressure on ecologicalenvironment, to overcome adverse natural conditions and to use resource effectivelyin northwest inland river basin. It is the only way to comprehensive constructionwell-off society too. However, there is the role of mutual coercion between regionalurbanization and water resource environment, which has aroused wide attention ofmany domestic and foreign scholars on this. Their mode of action andcharacteristics become a hotspot of current research.Secluded hinterland of the Shiyang River Basin, located in the eastern HexiCorridor of Gansu Province. And Shiyang River is one of the three largest aridinland rivers in Gansu province. Shiyang River possesses the typical features ofwater resource and environment of the northwest dry area. Its climate is dry and theprecipitation is scarce. Due to the serious shortage of water resource, the conflictbetween water utilization and water supply in this area has become more and moreserious. The long-term unreasonable use of water resource made the regionaleco-environment face the crisis of collapse. As the development of social economyand the continuous expansion of the cities’ scale, urban water supply becomes moresevere. Water shortage has become the "bottleneck" to China’s social and economicsustainable development. Located in the heart of the middle and upper reaches ofthe Shiyang River Basin, Liangzhou district is the most important part of the wholeShiyang River Basin with the highest population density and most vulnerableecological environment. So the choice of making Liangzhou area as the researchobject of this paper has a real and urgent meaning to the research of urban waterresource carrying capacity and modest population scale based on this.The research is built on the concept of sustainable development. And throughthe analysis and reference of existing water resource carrying capacity’s calculation method and model, the model of the three factors of water resource carryingcapacity has been put forward to explore mutual coercion between water resourceand urban scale and to search for the city’s moderate population scale which isbenefit to sustainable urban development combined with local water resourcesituation. The main contents include:Chapter I is an introduction.It introduces the background, the significance ofthe topic, the main research contents, the technical route and research methods.Chapter II is the general situation of the study area. The natural and geographiccondition of Liangzhou district is analyzed respectively from geographical location,geological landforms, climate, hydrology, water resource, soil and vegetation andother aspects. Then, the characteristics of Liangzhou district current social andeconomic development are described from population, economic and socialdevelopment level.Chapter III is to analyze the status, development and utilization of waterresource. And through the prediction of the future available water resource ofLiangzhou district, we have an initial understanding of the overall situation of waterresource in this study area.Chapter IV is to analyze the characteristics of urbanization and the interactionstress of urbanization and water-environment in Liangzhou district. At last,regression analysis, grey system theory and other methods are used to predict theeconomic aggregate of each national economic sectors of this area.Chapter V is the empirical research about Liangzhou appropriate scale basedon the water resource carrying capacity. Firstly the three factors computing modelfor urban water resource carrying capacity is proposed. Using the degree ofaccommodative and overload calculation formulation, a quantitative analysis ofmodest scale of the study area under the restriction of water resource from2001to2009is made. The result shows that water resource in Liangzhou is overloading.Then propose the measures of returning farmland to forest, improving the utilizationcoefficient of irrigation water, strengthening the urban sewage treatment capacityand reducing water consumption quota for all sectors within reasonable limits. Topredict the2010-2020moderate urban scale based on the water resource carryingcapacity, the result shows that: the threshold of Liangzhou city’s appropriate scale in2020can be reached87.89million based on water resource carrying capacity.However the forecast urban population is just68.62million. Although the urban population of2020’s appropriate urban scale threshold restricted by water resourceis significantly higher than predicted, it actually shows declining trend. So webelieve that the water resource to urban development restricted effects still existsand the situation is not optimistic. For the larger proportion of farmlandwater-saving, making the city’s modest scale threshold was significantly higher thanforecast number of urban population, the entire Liangzhou severe water shortage,while the population is increasing, food demand and farmland water demand willnot be an unlimited number, the economic growth based on the farmlandwater-saving can only solve the moment of hardship. For the development of social,growth of the economy and the expansion of urban capacity, need to find moreeffective and long-term measures.Chapter VI is the conclusion and prospect. Main conclusions, shortcomings,and future research commendations are summarized in this part.