Evaluation Of Snail Control And Schistosomiasis Prevention Forest Ecosystem Services In Dongting Lake

The evaluation of ecosystem service has an important guiding role in the decision of the current ecological environment management system.At the same time it can make policymakers have a scientific and accurate understanding of ecosystem services,coordinates the economic development and ecological construction.In this study the In VEST model were used to evaluation the water supply,soil conservation,carbon storage,snail control and schistosomiasis prevention in 2005,2010 and 2015 of Dongting Lake.We also combine the market value method and shadow engineering method for the monetization of ecosystem services,which can provide basis for quantitative evaluate the ecosystem service and scientific understanding the value of ecosystem services of snail control and prevention forest in Dongting Lake.The results are as follows:(1)Based on the land use/cover type,precipitation,evapotranspiration soil,digital elevation model,snail control forest area,snail area and schistosomiasis epidemic,and the authoritative datas of schistosomiasis.The data processing of Arcgisl0.2,the water conservation,soil conservation and carbon storage modules parameters of the InVEST model were revised and improved,and the spatial distribution of the ecological service of the snails in the Dongting Lake area was demonstrated.(2)Through the calculation of the water conservation function,it is concluded that the water conservation of different land use is difference.The snail control and schistosomiasis prevention forest as a special land use type,the water conservation is the same as that of forest land,and sort:forest land(snail control and schistosomiasis prevention forest)>cultivated land>grassland>residential land>unused land>waters.In 2010 the per hectare of forest land water conservation was 1.27×108m3/ha,which was higher than that of cultivated land、waters、residential land and unused land of 0.01×108m3/ha,1.26×108m3/ha,0.04×108m3/ha,0.37×108m3/ha,respectively.And less than that of grassland of 0.03×108m3/ha.But in 2015 the per hectare of forest land water conservation quantity was 1.08、108m3/ha,less than that the cultivated land、grassland and residential land of 0.08×108m3/ha,0.06×108m3/ha and 0.02×108m3/ha,respectively.And higher than that of waters and unused land of 1.07x108m3/ha and 0.22×108m3/ha.From the spatial distribution of water conservation in the Dongting Lake area,the water conservation of the Snail control and schistosomiasis prevention forest compare well with the forest land,the unit area water supply of Yueyang city is the largest and the smallest county is Taoyuan.(3)Through the calculation of the soil conservation,it is concluded that the soil conservation of different land use is difference.The snail control and schistosomiasis prevention forest as a special land use type,the soil conservation the same as that of forest land,and sort:grassland>forest land(snail control and schistosomiasis prevention forest)>waters>cultivated land>residential land>unused land.In 2010 the per hectare of forest soil conservation was 13.39t/ha,which was higher than that of cultivated land、waters、residential land and unused land of 11.09t/ha、10.36t/ha、11.54t/ha and 12.63t/ha,respectively,but less than that of grassland was 6.65t/ha.In 2015 the per hectare of forest soil conservation quantity was 8.88t/ha,which was higher than that of cultivated land、waters、residential land and unused land of 7.40t/ha、7.00t/ha and 8.26t/ha,respectively,but less than that of grassland was 5.24t/ha.From the spatial distribution of soil conservation in the Dongting Lake area,the soil conservation of the snail control and schistosomiasis prevention forest consistent with the forest land,the unit area soil conservation of Yueyang city is the largest and the smallest county is Taoyuan.(4)Through the calculation of the carbon storage,it is concluded that the carbon storage of different land use is difference.The snail control and schistosomiasis prevention forest as a special land use type,the carbon storage of snail control and schistosomiasis prevention forest higher thann that of the no-snail control and schistosomiasis prevention forest,and sort:grassland>snail control and schistosomiasis prevention forest>no-snail control and schistosomiasis prevention forest>unused land>cultivated land>residential land>waters.In 2010 the per hectare carbon storage of the Snail control and schistosomiasis prevention forest was 276.20 t/ha,which was higher than that of the non-Snail control and schistosomiasis prevention forest、cultivated land、residential land and unused land of 0.13 t/ha、234.56 t/ha、273.29 t/ha and 112.00 t/ha，respectively,but less than that of grassland was 4.03 t/ha.In 2015 the carbon storage of the snail control and schistosomiasis prevention forest was 270.28 t/ha,which was higher than that of the non-Snail control and schistosomiasis prevention forest、cultivated land、residential land and unused land of 0.14 t/ha、228.71 t/ha、267.11 t/ha and 123.00 t/ha,respectively,but less than that of grassland was 14.00 t/ha.From the spatial distribution of soil conservation in the Dongting Lake area,the largest city and the smallest county carbon storage of the Snail control and schistosomiasis prevention forest is Yueyang and Taoyuan.(5)Through the calculation of the snail control and schistosomiasis prevention forest,the results showed that the differences of snail control and schistosomiasis prevention in different counties of Dongting Lake in 2005～2015,Taoyuan County has the largest decreased number of snails and the largest reduction rate.Yuanjiang City is the largest reduction in schistosomiasis patients,Linli County’s schistosomiasis patients increased,and the counties schistosomiasis reduction rate of more than 95%are Taoyuan County,Changde City,Wangcheng County.Linli County is the largest increased rate in schistosomiasis patients.(6)Among the value of ecosystem services in Dongting Lake,water conservation have the greatest value,and followed by carbon storage,Snail control and schistosomiasis prevention and soil conservation.The unit area value of ecological service of snail control and schistosomiasis prevention forest is higher than that of non-snail control and schistosomiasis prevention forest was 0.07×104 yuan.The maximum value of snail control and schistosomiasis prevention forest service is Yueyang city,the smallest is Taoyuan county.Combined with the above ecosystem services,the value of ecological service of snail control and schistosomiasis prevention forest is enormous.Construction of snail control and schistosomiasis prevention forest can improve the comprehensive ecological service of Dongting Lake.