Research On Water Resources Carrying Capacity And Water Cycle Evaluation Of River Basin

Water resource is a kind of important natural resource as well as strategic economic resource. With the rapid development of social economy, the shortage of water resource and the deterioration of water environment start to appear gradually as a problem. Water resource has become one of the key factors that restrict the sustainable development of social economy and ecological environment. Under the background of Taizi River basin and around the problems that exist there, the paper has developed some relative researches as below:(1) Though the analysis on the development and the utilization of water resources in Taizi River basin now, point out that the shortage of water resource, the deterioration of water quality and the backwards of water management are the main problems in Taizi River basin in nowadays. In view of the phenomenon of ecological deterioration that appears in Taizi River basin and basing on the analysis and summary of the calculation methods about the water required for the minimum eco-environment, the water required for the minimum eco-environment in the Taizi River channel has been calculated by using Montana method and the average discharge in the driest month of the decade. Provide a scientific evidence for the sustainable utilization and management of the water resource in Taizi River basin.(2) Aiming at the purpose and demand of water quality evaluation, put forward a kind of new comprehensive evaluation method of the water quality—a evaluation model for water quality based on factor analysis fixed weight. The model makes full use of the characteristic of factor analysis and get the weight of the water quality index by variance contribution rates of the common factors and factor score coefficients, the comprehensive index of water quality evaluation can be obtained by the index weights and standardization values of each water sample indexes, and then, the evaluation samples can be sorted and classed. This method is tested to be reasonable by comparing with other methods in sorting and classing water quality samples. Meanwhile, the model can get the main pollutants by doing analysis of formation factors for the polluted water body. It can also explore the space-time variation law for the water body when the datum is enough.(3) Propose a quantitative model for the carrying capacity of water resources, using carrying degree to present the size of the water resources carrying capacity, and divide the water resources carrying condition into "able loading" and "unable loading" for people always not only care about the specific carrying index of the carrying capacity of water resources but also pay more attention on whether the usable water resources can carry and the proportion of social economy scale in the future that the usable water can carry. In the calculation of concrete carrying index, considering water resources will take part in social economic activity as a kind of capital goods, compute water resources supporting capacity for the society economy by the production function in economics. Production function is a function that can presents the quantity relationship between the inputs of the productive factors and the outputs of the productions during the manufacturing process. We can get the relationship between water resources and social economy by using production function. Consequently, we can obtain the economy scale that the water resources can bear indirectly. Compared with other traditional economy scale calculation methods, this method is an ideal method because its principle is clearer, its calculation is simpler and the data required is not complex. It provides a new thought for calculating the carrying capacity of water resources.(4) Propose the thoughts and steps for making the water cycle of basin unit network model and establish a Taizi River water cycle unit network model aiming at Taizi River basin. The model has considered the water quantity, the water quality, and the ecology changes comprehensively. It has also considered the human activity impact on natural water cycle of a basin, namely the impact on social water cycle. Though the model, the artificial influence factors on Taizi River basin are analyzed.(5) Perfecting water cycle evaluation is a new subject in the research of water resources issues. The concept of perfecting water cycle is presented out and its connotation has been deep analyzed by analysis the characteristic of water cycle as well as its function in nature and in the development of social economy. Establish the frame structure of the evaluation indexes for water cycle and the evaluation model basing on analysis the theories of perfecting the evaluation indexes of water cycle. Propose using perfecting the comprehensive indexes of water cycle to represent water circulative conditions in a basin. The water circulative conditions can be divided into five grades: very perfect, comparative perfect, perfect, not perfect and morbidity. Compute the evaluative model by AHP. The evaluation system and the model are proved to be correct by analysis the water cycle conditions of Taizi River basin in 2002.In the end, a summary for the whole paper and some problems for further research are given.