Valuation Of Terrestrial Ecosystem Services And Values

Ecosystem services are the conditions and processing through which natural ecosystems, and the species that make them up, sustain and fulfill human life. They not only supply to human with the production of ecosystem goods, such as food , forage , timber , biomass fuels , natural fiber , and pharmaceuticals. Ecosystems also perform fundamental life support services, which include the purification of air and water, detoxification and decomposition of wastes, regulation of climate, regeneration of soil fertility, and production and maintenance of biodiversity, mitigation of floods, droughts, the erosive forces of wind and rain. 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 and their services are dominated directly by humanity. Economic valuation of ecosystem services is the base of scientific managing ecosystem and sustainable using natural resources. Today, ecosystem services and how to assess their values have become the researching hot spots in the fields of ecology and eco-economics.In this paper, using multidiscipline theories and methodologies, including ecosystem ecology, eco-economics, natural resources economics, environment science, the advances in ecosystem services characteristics, their economic valuation and their relations to sustainable development are literaturally surveyed and discussed,the theories and methods and their applications on valuation of terrestrial ecosystem services and accounting of environment degradation are outlined. The main research works are as following:(1) The advances in ecosystem services and their valuation and their relations to human well-being and development are literaturally reviewed;The concepts, contents and their driving force of terrestrial ecosystem services are analysized;The basis theories of ecosystem services and their valuation are summarized.(2) Based on the definitions and relationships among components, functions, processes and services of terrestrial ecosystem,guided by the scientific principle, systematic principles, independence, relevance, comparability, and so on. A framework of index system that suits China conditions for identifying, classifying and valuating ecosystem services is developed The index system has 4 levels, 28 items and 56 indicators. Using the methods of APH (Analytic Hierarchy Process), the weights of indexes were calculated, and the indexes were standardized by contrast value of indexes with theoretic indicator system. Here, terrestrial ecosystem services are grouped into four primary categories: production services, regulation services, cultural services and support services. The indexes system can provide scientific support for valuation of terrestrial ecosystem services in China.(3) The study reviews valuing methods for terrestrial ecosystem services, and then establishes relationships among processes, functions, services, values and valuing methods. Methods selecting procedures are established according the relationship between service indexes and valuing methods. The study presents systematically a set of evaluation methods for terrestrial ecosystem services including woody productions, holding water sources, flood control, protection of surface soil, maintenance of nutrient, preventing sediment, sequestration of carbon dioxide, release of oxygen, absorption of sulfur dioxide, interception of dust and purification of atmospheric pollution.(4) It is first time to estimate desert ecosystem services value by using method indexes the above-mentioned. The results showed that the total value of annual desert ecosystem services in China was about $2284.39×108/a, among which, the percentage of production took up 37.28 %, that of carbon sequestration and oxygen releasing accounted for 33.26 %, nutrition laying 0.89 %, erosion control and sediment retention 7.09 %, water and soil conservation 9.48%,biodiversity function maintenance10.56 %, and recreation and culture 1.44%.