Research On Ecological Economic Value Of Regional Water Resources Based On Emergy Theory

How to evaluate the economic value, social value and ecologic environment value of water resources to a common scale is a difficult and hot topic in water resources field by now. From the angle of water resources eco-economic system, introducing emergy theory, a systematic study of emergy evaluation of ecological economic value of water resources is conducted. The main researches are as follows:(1) According to its resources characteristics, the source and formation mechanism of economic and ecological value of water resources are revealed, and the content and structure of which are defined based on the ecological and economic functions and eco-economic system of water resources.(2) Based on emergy theory and the content of economic and ecological value of water resources, the frame of emergy evaluation is constructed, which provides a new analysis method for emergy evaluation of ecological economic value of water resources.(3) Based on the energy recycling and transformation in water eco-economic system and the construction principles of energy and emergy network, the energy and emergy network of water eco-economic system and its subsystems are constructed, including industrial subsystem, agricultural subsystem, living subsystem and ecological subsystem, which are the foundation of quantitative evaluation of ecological economic value of water resources.(4) Water bodies are divided into precipitation, natural resource water, engineering water and sewage, based on the energy transfer and conversion processes of water cycle and the effects on transformity. The emergy calculation methods of transformities of different water bodies are studied.(5) The contribution rates of water resources in industry, agriculture, and living are put forward, and the emergy quantification methods of which are given based on energy analysis of water eco-economic system. The emergy evaluation methods of economic value, social value and ecologic environment value of water resources are put forward based on its structure and embody.(6) The application was carried out in Zhengzhou city as a case study, the energy and emergy network graphs is protracted and emergy flow of system is analyzed, and then the water ecological economic value of Zhengzhou city in is evaluated for past 6 years extending from 2000 to 2005. The results of this paper are compared with water price and water resources fee of Zhengzhou city, and some idea and suggestions on water resource management in the future are given.(7) Combining the theory and the application research results, the conclusion and the questions need to be studied deeply are presented.