Effects Of Land Use Change On Ecosystem Services

To cope with the increasingly widespread regional and global scale ecological problems, more attention has been payed to study the relationship between the economy(human activities) and ecosystem services. The ecosystem service evaluation has important significance for sustainable development, and is the basis of ecosystem management. The spatially distributed model provides a new evaluation methodology based on 3S technology and overcomes the limitations of the traditional quantitative assessment methods. Spatially distributed model can achieve spatial expression, dynamic analysis and quantitative assessment for ecosystem services. This study chose East Tiaoxi watershed as the study area. It analysised the pattern of land use based on remote sensing and geographic information technology during 20 years. The two types of ecosystem services that study assessed using In VEST model were water yield and water purification, and discussed the space distribution features. The main conclusions were as follows(1)During the 20 years, forest and construction area increased. Farmland, water and bare land were reduced. The part of farmland and bare land converted to construction land. Bare land converted to forest, farmland and construction land continuously. The increase of construction land was very obvious.(2)On the sptial distribution, the water yield and water purification showed higher from northwestern to southeastern in East Tiaoxi watershed.(3)The water yield were 17.46×108, 12.69×108 and 18.36×108mm in 1991, 2000 and 2010. Mainly affected by climatic conditions and land use. The water purification was declined during the study period.