As the most developed area in China,the Yangtze River Delta had undergone rapid urbanization since the reform and opening up in 1978. The ecosystem services and functions were both affected significantly by human activities which can be represented by land use change. Landsat5 TM imageries in 2009 and 2010 covering the Yangtze River Delta were selected and classified for land use with overall accuracy and Kappa coefficient were 87. 5% and 0. 82 respectively,and seven land use types,specifically,woodland,grassland,farmland,wetland,water body,construction land and unused land were considered. The land use maps in 1980 and 2005 were from Chinese Data Sharing Infrastructure of Earth System Science. The two sources of land use maps were geo-referenced. The temporal and spatial dynamics of land use in the Yangtze River Delta from 1980 to 2010 were analyzed supported by ArcGIS software. Then a simple ecosystem service value estimation method initiatively proposed by Costanza and localized by Xie was adopted to calculate the ecosystem servicevalue. The response of land use change on ecosystem service value was further analyzed. The results showed that:( 1) the area of construction land increased by 446. 10% from 1980 to 2010. Followed the greatest change amplitude of all the land use types,unused land,cropland,grassland,woodland and water changed 285. 9%,-31. 5%,-76. 2%,-5. 4%,42.9% in the same order.( 2) The total ecosystem services value of the Yangtze River Delta decreased from 4. 21billion in1980 to 4. 02 billion Chinese Yuan( CNY) in 2010,reduced by 4. 40%. The change trend of ecosystem service value of woodland and grassland were nearly the same and presented increasing from 1980 to 2005 and decreasing from 2005 to2010. Ecosystem service value of farmland and wetland were both on the trend of decreasing while water body and unused land increased from 1980 to 2010. In addition to the ecosystem service value of water supply,recreation and culture function and waste treatment increased while the other ecosystem functions declined from 1980 to 2010.( 3) Extremely low area of ecosystem service value( ESV) mainly located in the urban region and it increased dramatically following by urban expansion along the Yangtze River and Hangzhou Bay from 1980 to 2010 was and spatially consistent with distribution of arable land. The low area of ESV in the Southern Zhejiang increased while in the north of the Yangtze River Delta decreased gradually in the last 30 years. The medium area of ESV had the same spatial distribution as woodland and mainly located in the mountainous area of Zhejiang Province. The low area of ESV greatly reduced,particularly in the Southern Zhejiang.The spatial distribution of high and extremely high area of ESV was consistent with that of the water body.( 4) The ecosystem service value of Changzhou,Huzhou,Jiaxing,Nanjing,Taizhou increased by 2. 54%,6. 06%,6. 14%,11.87% and 7. 96% while the other cities decreased during 1980—2010. Urbanization,industrial restructuring were major factors to influence land use change,which caused the construction land expansion and the loss of farmland,woodland and grassland. ESV declined during 1980—2005 mainly resulting from farmland and wetland reduction,while ESV declined during 2005—2010 and was caused by reduction of grassland,wetlands,farmland and woodland. Water conservation,waste treatment,soil formation and protection and biodiversity conservation were the major ecosystem service functions in the Yangtze River Delta.
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