Assessing the variable ecosystem services relationships in polders over time: a case study in the eastern Chaohu Lake Basin, China

Land use changes can isolate habitat patches, thereby aggravating the fragmentation of these units and altering natural ecological processes. Thus, it is necessary to analyze the responses of ecosystem services to changes in land use over time. Polders, a typical floodplain landscape in the Chaohu Lake Basin, were selected as the study area to evaluate how ecosystem services respond to changes in both land use and patch size over time. Multiple approaches, including remote sensing, geographical information system and correspondence analysis, were used. The results showed that the total ecosystem services were increased from 9.97 x 10(8) to 1.02 x 10(9) Yuan for all polders. Based on a correspondence analysis, recreation and culture, water supply and waste treatment are the ecosystem services that depend on water bodies, whereas six other types of ecosystem services (biodiversity protection, climate regulation, food production, raw material, soil formation and protection and gas regulation) depend on soil. Therefore, there are trade-offs between the ecosystem services provided by farmlands and those provided by water bodies, between supporting and provisioning services and cultural services in the polders, and between provisioning services and most regulating services. Furthermore, trade-offs and synergies were detected among regulating services. In this study, the relationships between patch sizes and ecosystem services were significantly changed during the 1985-2007 period, particularly from 2000 to 2007. The area variation of special land use can drive changes in these relationships. Notably, correspondence analysis can be used as a method to analyze synergies and trade-offs among multiple ecosystem services.