Economic Value Evaluation Of Paddy Ecosystem’s Services And Functions In Jingzhou

As a manual and natural complex ecosystem type, paddy ecosystem has the dual attributes of nature and society. It also provides us with all kinds of products and services while it supplies living space for many creatures. Conventional wisdom suggests that paddy ecosystem only provides primary agricultural products for human beings, such as food and fiber. But in fact, paddy ecosystems have other functions and services, like the hydrologic cycle regulation, climate regulation, soil organic matters cultivation and conversion, providing plots for landscape and cultivation, bio-diversity reservation and greenhouse gases emission. However, with the rapid development of modern intensive agriculture, pesticides, chemical fertilizers and all kinds of growth regulators were widely used, and domestic and industrial contaminants were discharged into paddies, which destroyed natural vegetation and water creatures of agricultural region and its edge, lowered biodiversity level, and then weakened the functions of paddy ecosystems.Based on the researches of domestic and foreign scholars, this study started from regional scale and conducted a monetized quantitative evaluation of paddy ecosystem’s services and functions in Jingzhou with survey, detection and field experiments. Aiming at providing theoretical basis and technical support for ecosystem reservation project, and supplying basis for establishing route map of sustainable agricultural development.The preliminary research results are as follows:(1) The value of production function:based on field experiment and statistical data, the value of rice and straw produced in the paddy ecosystem was estimated with market valuation method. Eliminate production cost (the cost of fertilizers, pesticides, human and animal), the value of paddy ecosystem’s producing rice and straw in Jingzhou in 2015 were respectively 4.16 billion CNY and 1.06 billion CNY, the total value of production was 5.22 billion CNY in 2015.(2) The value of hydrological adjusting function:this part concludes water consumption, flood-mitigation storage and water conservation. The value of water consumption was evaluated with market valuation method, and the value of flood-mitigation storage and water conservation were evaluated with shadow project approach. The value of the three parts were respectively 0.42 billion CNY,0.43 billion CNY and 1.19 billion CNY. The total value of paddy ecosystem’s hydrological adjusting function in Jingzhou in 2015 was 1.20 billion CNY.(3) The value of climate regulation function:the value of paddy ecosystem’s regulating climate was assessed with substitute cost method, the value was 1.53 billion CNY in Jingzhou in 2015.(4) The value of gas regulation function:it concludes value of carbon dioxide fixation and oxygen production, greenhouse gas emissions. The value of carbon dioxide fixation and oxygen production was evaluated with carbon tax approach and industrial cost method. The value of greenhouse gas emissions was estimated with carbon tax approach. The results showed that, the value of carbon dioxide fixation and oxygen production, greenhouse gas emissions were respectively 16.80 billion CNY and 5.36 billion CNY. The total value of paddy ecosystem’s gas regulation function in Jingzhou in 2015 was 11.43 billion CNY.(5) The value of organic matter accumulation function:the quantity of accumulated organic matter was measured by the balance of input and output, and assessed with market valuation method. The results showed that the value of paddy ecosystem’s organic matter accumulation function in Jingzhou in 2015 was 1.77 billion CNY.(6) The value of environment purification function:air purification and water purification are concluded. The value of the two part was estimated with industrial cost method. That is, it was assess by the quantity of purified pollutants combined with industrial disposing cost of pollutants. The value of air purification and water purification were 2.06 billion CNY and 0.13 billion CNY. The total value of paddy ecosystem’s environment purification function in Jingzhou in 2015 was 2.20 billion CNY.(7) The value of organic solid waste disposing function:the common organic solid waste from agriculture were grain straw and animal waste. In this study, industrial cost method was applied for estimating the value of paddy ecosystem’s organic solid waste disposing function. Analysis showed the value of grain straw and animal waste disposing function respectively were 0.09 billion CNY and 1.23 billion CNY. The total value of paddy ecosystem’s organic solid waste disposing function in Jingzhou in 2015 was 1.32 billion CNY.(8) The value of landscape and education function:contingent valuation method and equivalent factor method were both used to evaluate the value of paddy ecosystem’s landscape and education function. The results was that the value of paddy ecosystem’s landscape and education function in Jingzhou in 2015 was 0.59 billion CNY.(9) The value of biodiversity reservation function:for the value estimation of this function, contingent valuation method was applied. Last results indicated that the value of paddy ecosystem’s biodiversity reservation function in Jingzhou in 2015 was 2.17 billion CNY.(10) Total value of paddy ecosystem’s services and functions:the study showed that, the total value of paddy ecosystem’s services and functions in Jingzhou in 2015 was 27.44 billion CNY. And the total value accounted for 18.5% of the gross regional domestic product in Jingzhou in 2015. The direct production value was 5.22 billion CNY, which accounted for 19.9% of grass agricultural production in Jingzhou.Ecosystem has important ecological function, plays a significant role in the national ecological security. Taking Jingzhou for an example, the value of its ecological function was 4.1 times as that of economic function. Therefore, the people of all circles should be appealed to ecosystem reservation. First, the national government should inspire and instruct agricultural producers to adapt excellent production mode, and pay more attention to ecologic benefits while pursing economic benefits by kinds of means, like increasing subsidies for grain farmers, establishing the agro-environment protection mechanism and so on. Besides, local government can attract investment according to local conditions, and scientifically and rationally use resource to develop new-type agriculture production forms. At last, agricultural producers should establish right concept, and develop resource saving and environment friendly agriculture forms, to ensure the development of sustainable agriculture.