Study On Effective Utilization Of Rain Water Resources And Ecological Environment Construction In Karst Mountain Region Of Northwest Hunan Province

Study of this thesis focuses on two key aspects. One is effective utilization of rainwater resources and the other is ecological environment construction in the karst mountain region of the northwest Hunan province. Based on analysis of ecological environment characteristics and essential problems in the karst mountain region of the northwest Hunan province, eco-agriculture construction of a case that is representative example of eco-agriculture construction only depending on rainwater and county scale are researched respectively in Cili county by applying ecology principle and method of system. As study of a case, factors of affecting effective utilization on rainwater and benefits of various measures in model effectively utilizing rainwater resources are analyzed, and study on relationship of region ecosystem development with model in practice is carried out. Then, agro-ecological information system (AEIS) of model system is established with support of GIS, and landscape changing of model system is researched by applying AEIS. As study on eco-agriculture construction in county scale, Synthetic benefits are evaluated on system and various eco-agriculture zones by applying method of fuzzy evaluation. The major conclusions can be summarized as follows:l.The existing problems in the karst mountain region of the northwest Hunan province are the problems of the regional ecology that are resulted from a lot of factors such as frangibility of ecological environment and low social-economic development level. The prominent conflict of cultivated land with overpopulation resulted from very low productivity of cultivated land is a key factor that affect region ecological environment and social-economic development.2.The factors that affect effective utilization of rainwater resources consist of heavy leakage and asymmetry seasonal distribution of rainfall and peculiar soil moisture character in coincidence. Especially, soil originated from carbonate rock has higher release rate of soil water and lower available water suction comparison with soil from other rock in the same region such as red soil. This character of soil moisture is the intrinsic factor ofsoil that brings out karst drought easily.3.As the analysis of benefits of model effectively utilizing rainwater resources showed, it has notable benefits of ecology, society and economic because field engineering, biology engineering, farming system and ecological technique which utilize effectively rainwater resources are integrated organically. The ecological benefits represent in increasing validity of soil moisture in field soil water pool and potential ability of holding soil water, and enhancing crop ecological adaptability to rainfall, and improving soil qualities and condition of climate in environment; Social and economic benefits represent in increasing productivity of land, expending income ways and resolving water source of life.4.As analysis of relationship region ecosystem development with model showed, many aspects are influenced by model effectively utilizing rainwater resources on ecosystem. Along with model development in region, productivity of land increases, cultivated land area holds stable, the conflict of cultivated land with overpopulation resolves, Pluralism of the domain agricultural production structures appears and the level of technology advances. The model makes region ecosystem harmony and sustainable development. Therefore, effective utilization of rainwater resources and the sustainable development of region ecosystem are coupled organically.5. Agro-ecological information system (AEIS) of model system is established with support of GIS. AEIS integrates figure dealing, data managing, analyzing with statistics and modeling. It includes basic information about model system such as resources, society and economic except geographic spatial information. It can support planning, design and management with ecosystem.6. Obtained results in landscape changing of model system by applying AEIS show that cultivated land holding stable...