Study On The Spatial And Temporal Variation And Prediction Of Land Ecosystem Service Value In Tongxiang City

Changes in land use patterns are an important cause of changes in the value of ecosystem services.The current rapid urbanization has led to dramatic changes in land use patterns,thus affecting the ecological environment.Therefore,it is important to analyze and assess the coupling relationship between land use and ecosystem service value to promote regional sustainable development.In this thesis,taking Tongxiang City,Zhejiang Province,which is located in the North Zhejiang Plain,as an example,based on remote sensing,GIS analysis and PLUS model,etc.,we extracted the land use and non-grain production information at plot scale from 2005 to 2020,analyzed the quantity and spatial distribution change pattern of each land use type in Tongxiang City,and then the dynamic changes of ecosystem service values in Tongxiang were assessed and analyzed.Finally,scenario prediction of land use in Tongxiang City in 2030 and calculation of its ecosystem service value are made,so as to propose corresponding countermeasures for the future sustainable development of the region.The main contents and conclusions of this thesis are as follows:(1)Based on the high-resolution remote sensing images and land use data,the information of each land use type and non-grain production in Tongxiang City from 2005 to 2020 was extracted,and the quantity and spatial distribution characteristics of different land use types and non-grain production were analyzed.The results showed that the number and spatial distribution characteristics of different land use types and non-grain production in 2005-2020.The results showed that the area of cultivated land and unused land continued to increase from 2005 to 2020,while the area of garden land,forest land and water area was decreasing year by year,and the construction land showed a trend of first increasing and then decreasing.Non-grain production showed a trend of gradual expansion from 2005 to 2020,with the total area increasing from 615.74 ha The expansion of non-grain production showed a spatial agglomeration effect,probably because some farmers engaged in non-grain production and obtained high economic returns,other farmers followed suit,thus further increasing the area of non-grain production.The expansion of non-grain production showed a spatial clustering effect,probably because some farmers engaged in non-grain production with high economic returns,other farmers followed suit,thus further expanding the area of non-grain conversion of cultivated land.(2)An ecosystem service value assessment model was constructed based on the ecological service value per unit area equivalence table,which was revised in the light of the actual situation of socio-economic development,and then the ecosystem service value of Tongxiang City was calculated.The results show that the value of ecosystem services in Tongxiang City showed a decreasing trend during the study period,with the total amount decreasing from 6.236 billion yuan to 2.453 billion yuan,a decrease of 3.783 billion yuan,mainly due to the transfer of a large amount of watershed and garden area to arable land and construction land.The changes in the value of ecosystem services vary significantly among towns and villages.In 2005-2020,the change of ecosystem service value in Wuzhen Township is more obvious and has been showing a decreasing trend,which is related to the continuous decrease of the local duck breeding area and garden area.In contrast,the ecosystem service value of Zhouquan Township has been higher,remaining above 500 million yuan,which is mainly due to the more water area in Zhouquan Township.(3)Based on the land use data of Tongxiang City in 2005,2010,2015 and 2020,the spatial distribution pattern of land use and the change of ecosystem service value in 2030 under three scenarios in Tongxiang City were simulated with the help of PLUS model.The results show that the total value of ecosystem services in the natural development scenario is 1.566 billion RMB;the highest value of ecosystem services in the ecological protection scenario is 1.689 billion RMB,which is due to the emphasis on the protection of lands such as gardens and waters;the lowest value of ecosystem services in the urban development scenario is1.126 billion RMB.The urban development scenario focuses on the development of urban economy,and the scope of construction land is expanding outward,which occupies more ecological land and eventually leads to the reduction of ecosystem service value.