دانلود رایگان مقاله انگلیسی منطقه بندی ظرفیت حمل محیطی آب برای حمایت از مدیریت و توسعه منابع آب پایدار در چین - الزویر 2018

ABSTRACT

With the rapid economic growth and social development in China, conflicts over water resources between human and nature are continuously increasing which is attracting the attention of researchers. At the same time, discharge of water pollutants and exploitation of water resources pose a daunting challenge to the sustainable development of economy and society. China consists of 34 provincial administrative regions having similar or different characteristics in the levels of economic development, water resource endowment, water environmental capacity and water environmental pressure. Among these, it is meaningful to analyze spatial similarities and variations in water environmental carrying capacity (WECC), which contributes to carrying out different and scientific strategies for the management of water environment and for sustainable economic and social development in China. An index system is established to quantify WECC from the perspectives of carrying capacity, environmental pressure, vulnerability of water environment and exploitation and utilization potential. The kmeans clustering method is applied to conduct the similarity combination based on the quantification of 4 integrated indicators using catastrophe progression method. The silhouette coefficient is introduced to measure the quality of clustering and to determine the optimal clustering number. The obtained results indicate that carrying condition of water environment becomes more and more better and exploitation and utilization potential of WECC is decreasing gradually from the east to the west in China, and there are more overload in the north provinces and less in the south. In addition, water environmental vulnerability in the west is higher than that of central and eastern provinces in China. The optimal clustering number is 4 obtained by calculating the silhouette coefficient. Also, 31 provinces are categorized into 4 sub-areas i.e. key protected area, controlled development area, optimized development area and prioritized development area. The suggestions on the corresponding bidirectional regulation to different sub-areas are also put forward to provide a scientific reference to rational distribution of economic development, elaborate management of water environment as well as regional sustainable development in the future.

4. Conclusions

An index system of water environmental carrying capacity is established by carefully considering the perspectives of water environment carrying status, water resources carrying status, water environmental vulnerability and exploitation and utilization potential. Besides, quantification is carried out on the integrated indicators based on the catastrophe progression method. Then, the spatial distribution of 4 comprehensive factors representing WECC is analyzed. The obtained results through this investigation reveal that the carrying condition of water environment becomes increasingly better and the exploitation and utilization potential of WECC is decreasing gradually from the east to the west in China, which corresponds to the differences existing in the spatial distribution of the level of economic development. As far as the water resources carrying status is concerned, there are more overloading provinces in the north and less in the south, which is roughly the same as with the distribution of precipitation. In addition, water environmental vulnerability in the west is higher than that of central and eastern provinces due to different locations along the main rivers and also due to the spatial distribution of national nature reserves.

The k-means clustering method is applied to identify the similarities as well as different characteristics of WECC in the 31 provinces. The silhouette coefficient is introduced to measure the clustering quality and to determine the optimal zoning number. The observed results show that the average silhouette coefficient is the largest when k = 4, which represents the best clustering quality, i.e. the optimal clustering number is 4. Therefore, 31 provincial administrative regions are categorized into 4 areas, including key protected area, controlled development area, optimized development area and prioritized development area. Following this, suggestions on the corresponding bidirectional regulation to different sub-areas have been put forward to provide a scientific reference to the rational distribution of economic development and in assisting the management of water environment and regional sustainable development.