Assessment And Evaluation Of Ecosystem Services In Shanghai Green Belt

Urban forests play important roles in maintaining the balance of urban ecosystems and improving living environment. Assessment and evaluation of urban forest ecosystem services will reflect the services directly.As an important part of urban forests in Shanghai, "Shanghai Green Belt" was selected for study object. The survey of plant communities structural characterisitc including diameter at breast height (DBH), height(H), bifurcate height(BH), leaf layer height(LH),crown diameter(CD), total coverage(TC)and stand density(SD). The experiment of ecosystem services index including temperature, humidity, noise, dust accumulation ability and the concentration of microbe content, negative-ion. The survey and experiment were carried out from Jun.,2010 to Sep.,2010., in 39 sample points of Shanghai Green Belt. The purpose was to analyze the difference of ecosystem services between different gradient of Green Belt, and to explore the impacts of community structure on ecological services. Based on these datus and by applying the methods of substitution of the expenses, and shadow project,etc., reference to "Specifications for assessment of forest ecosystem services in China"(LY/T1721-2008), the ecosystem services of Shanghai Green Belt were evaluated, to accurately reflect the the quantities and characteristics of the total ecosystem services value of Shanghai Green Belt. This study could provide theoretical basis for the construction and ecosystem service improvement of Shanghai Green Belt.The results showed that the atmosphere environmental purification service was better in urban Green Belt, the microclimate adjusting service was better in industrial Green Belt, meanwhile this service is related with forest built time. The ecosystem services of Shanghai Green Belt were in accordance with the forest function orientation. Urban Green Belt was built to purify atmosphere environment and make people feel comfortable. However, industrial Green Belt was built to alleviate and reduce environment pollution..In order to reveal main factors, the correlation between community structural characteristics and ecosystem services was analyzed.The results showed that all the ecosystem service indicies regulated by the community structural characteristics.The community structural characteristics can be divided into two categories:the canopy structure indicies and the biomass indicies. The following ecosystem services were regulated by canopy structure indicies:negative-ion supply and noise reduction.The following ecosystem services were regulated by biomass indicies:microclimate adjustion, bacteria inhibition and dust accumulation.The evaluation result showed that in 2010, the total ecosystem services value of Shanghai Green Belt was 8.9946×108 yuan. The sequence of the service function values was as follows:microclimate adjustion> atmosphere environmental purification> water conservation>C fixation and O2 release>forest recreation> biodiversity conservation>provision of forest products>soil conservation. Main ecosystem services of Shanghai Green Belt were temperature regulation and atmosphere environmental purification.