Evaluation Of Forest Ecosystem Services Of Taihuyuan Watershed In Lin'an, Zhejiang Province

Ecosystem services refer to the natural environment conditions and utility which maintain the survival of humanbeings and are formed within the ecological system and during the process of ecology. Forests as the main body of the terrestrial ecosystem, their ecosystem services have always been the hot issue of the study of ecology. The previous studies mainly focused on ecosystem services in large scale, national or regional. The paper conducts the research in watershed scale to assess the value of forest ecosystem services in Taihuyuan watershed, and tries to provide some suggestions to the integrated planning of watershed.Applying frequency analysis and theoretical analysis method, according to the factual status of the forest resources of Taihuyuan watershed, the paper sets up an appraisal index system consisting of five first-class indexes: fixing carbon and releasing oxygen, water conservation, soil conservation, air purification, biodiversity conservation. Eight second-class indexes: carbon fixing, oxygen releasing, water regulation, water purification, preservation of fertility, reducing sediment deposition, SO2 assimilation, dust retention. Detailed descriptions of the formation mechanism and the evaluation methods of ecosystem services are also been shared.During the Sep. to Oct. 2010, the author investigated the 6 forest stands in the research area and estimated the amount of ecosystem services per unit area of the 6 main forest stands in the research area: bamboo forest, broadleaved softwood forest, Pinus massonian forest ,broadleaved hardwood forest, Cunninghamia lanceolata forest, Carya cathayensis Sarg. forest. With reference to previous studies, the paper identifies the value of unit amount of ecosystem services and figures out the value of ecosystem services per unit area of different forest stands. Based on the given number of forest stand area, the total value of ecosystem services of the whole watershed is finally calculated out. It concludes that the results of evaluation are: the total value in the Taihuyuan watershed is 3633.93 ten-thousand yuan, among which, the value of soil conservation is 1254.94 ten-thousand yuan, accounting for 34.53% of total value; fixing carbon and releasing oxygen, 1205.86 ten-thousand yuan, 33.18%; biodiversity conservation, 577.60 ten-thousand, 15.89%; water conservation, 532.07 ten-thousand, 14.64%; and air purification, 63.46 ten-thousand, 1.75%. The order of the per unit area value of ecosystem services from high to low is bamboo forest, broadleaved softwood forest, Pinus massonian forest, broadleaved hardwood forest , Cunninghamia lanceolata forest, Carya cathayensis Sarg.forest.