Risk Analysis Models And Application Of Ecosystem Services Value

The biota and physical structure of ecosystem provide a wide variety of marketable goods. Moreover, society is increasingly recognizing the myriad life support functions, the observable manifestations of ecosystem processes that ecosystems provide and without which human civilizations could not thrive. Recognition that ecosystems or ecosystem services are valuable, it is necessarily to quantify their value. Ecosystem services and how to assess their value and risk have become the researching hot spots in the fields of ecology mathematics and ecological economics. This thesis is aimed at the key to the questions ecosystem services value, a new theoretical framework has been advanced. The framework is composed mainly of emergy value of ecosystem services. The innovative study have made on ecological risk evaluation by integrating the quantification of the value of ecosystem services with the EVR model of risk analysis, and case study have made to evaluate the risk of Gansu province ecosystem services value. The main research works are as follow:(1) As the human population has grown and the power of technology has expanded, the scope and nature of this modification has changed drastically. Many ecosystems are dominated directly by humanity. Under this background, the author reviews the development of ecological risk analysis research and establishes Water resource carrying capacity model, soil fertility degradation risk model, Markov process risk model and integrated risk evaluation model.(2) Emergy analysis has been developed over the past 20 years by H.T.Odum. Emergy measures both the work of nature and that of human in generating products and services, as a science-based evaluation system that represent both natural values and economic values with a simple, universal unit. Ecological footprint and ecological carrying capacity models are also established to evaluate the value of ecological services.(3) Ecological risk analysis is a new marginal subject that studies issues on risk theory, modern ecology and environmental science, etc. Currently, quantitative assessing and integrative study of ecological risk is a significant issue in the world. Referring to the risk management framework which has formed in some developed country and combining with the content of the ecological risk analysis, a work flow and the indices assessing the risk of ecological risk analysis are generated.(4) Ecological Value at Risk model (EVR) is established to evaluate the risk of ecosystem services value basing on quantitative assessment of ecosystem service. EVR gives the largest loss the ecosystem might be suffered on a certain confident level in the future. The tail loss which indicates the average loss when the disaster happens is deducted. This enhances the forecasting capability of the EVR model. Basing on the emergy value of ecosystem services, I use EVR model to forecast the risk of Gansu province ecosystem services under the confident level such as 90%. The results showed by EVR model is that Gansu province ecosystem services emergy value will suffer the largest loss of 6.09×10²¹ sej and its average loss when the disaster happens is 9.45 × 10²¹ sej in the 90% probability. EVR can report the risk of an ecosystem through reporting a single data and report an average loss scale when disaster happens through expanding the model. These strengths make EVR facilitate the managers and decision makers of the ecosystem. The case study predicts the risk of ecosystem services value in Gansu province using EVR methodwhich provide quantitative analysis for the sustainable development of Gansu province.