Analysis Of Water Resources Carrying Capacity In The Yellow River Coastal Region Of Gansu Province

Water resource is one of the most important basic resources for human survival and social development. With the world economy and population growth, the demand of water resource is continuously increasing. That is to say water shortage has become a global problem. Water resources carrying capacity is the basis and prerequisite of regional socio-economic development, which is significant to realize the coordinated development of regional "water resources-ecological environment-socio-economy" composite system. So it has become the focus and hot topic in water science field nowdays.The study area is located at the Upper Yellow River, whose center is Lanzhou city and axis is the Yellow River. It is in the hinterland of Gansu Province, where connect east part with west part. Its climate appears a transition from semi-arid to arid. Also it is the traffic artery of Northwest China and the key area to make communication between Western Regions and Mainland since ancient times, as the unique pathway of the famous ancient Silk Road. The main power of modern industry and resources of technology and education in Gansu Province had been concentrated in this area, where has become the core region of economic growth in Gansu Province or even the Northwest China, showing an important strategic position.60 years after New China established, agriculture development dominated by cropland irrigation has effectively promoted the process of industrialization and urbanzation in the region, and now it has achieved primary industrialization. As a district where population and industry all concentrate on the Upper Yellow River, its sustainable development will deeply affect Gansu Province, Northwest China, even the Yellow River basin.This paper took county units as objects to study water resources carrying capacity in the area. According to predicting results of water resources carrying capacity in future years, corresponding measures were proposed for regional development. which is significance to socio-economic development. Water Resources data in this paper come from The Major Function Area Plan of Gansu Province-the Available Water Resources Research Subject. The data of water resources assessment are the average value from 1956 to 2006, and the guarantee rate is about 75%. Social and economic data come from Gansu Rural Yearbook(1993-2007). Analysis time period start from 2006 and forecast years are 2015,2020 and 2030.Firstly, based on literature data collection and analysis, we summaried and disscussed water resources carrying capacity theoretically. Considering physical geography, social-economy and water resources overview in the Yellow River Coastal Region of Gansu Province. It analysed the dynamic changes of water resources carrying capacity through constructing system dynamics model. The results showed that five variables include cropland irrigation areas, irrigation quota, water-saving technology, the scale of non-agricultural industries and ecological water are main factors that greatly impact on the water resources carrying capacity.Secondly, according to the demand of water resources carrying capacity index prediction, we established prediction modules of corresponding indexes relate to society, economy and ecological environment development indexes in the Yellow River Coastal Region of Gansu Province. Based on the present situation of water resources carrying capacity, the impact factors on water resources carrying capacity were analyzed, and some main factors were selected to model multi-scenario assumptions and analyzed water resources carrying capacity of the whole study area under various scenarios conditions. The result showed that each scenario has its own advantages and disadvantages among four typical scenarios, the most favorable option is the coordinated development scenario.Finally, under the two hypothesis preconditions that water resources can flow and can not flow to other area, we contrastively analyzed the change trend and carrying status of water resources carrying capacity in the Yellow River Coastal Region of Gansu Province. The result showed that in the case that the allocation of water resources is not restricted by space, the goal of overall well-off may be achieved for in this region in 2020, but there are huge differences internal. Four living levels include the subsistence level, the relative ample life, primary well-off and overall well-off still exist. However, the overall average value conceals differences within the region. The data of water resources carrying capacity obtained by overall calculation are larger than that by summation of all counties. Because of the water resources non-uniform distribution in each country, it is difficult to really reflect socio-economic diversities.In this paper, we take the water resources carrying capacity in the Yellow River Coastal Region of Gansu Province as study object and use the system dynamics model to simulate the process. The conclusions have certain reference for future development of this region.