Spatiotemporal patterns of the trade-off and synergy relationship among ecosystem services in Poyang Lake Region, China.

Poyang Lake region is the largest freshwater lake impacted area in China. Quantitative analysis of trade-off and synergy in ecosystem service is of great significance for realizing regional sustainable development. Based on multi-source data of remote sensing, soil, meteorology and DEM, we quantitatively measured food supply service, soil conservation service and water yield service in Poyang Lake region from 2005 to 2015, and analyzed their spatiotemporal patterns and evolution characteristics. The spatial and temporal characteristics of trade-off and synergy between services on the scale of 1 km×1 km were analyzed by using correlation analysis, hot spot analysis and spatial mapping method. The differences of ecosystem services and their relationships in the perspective of land use were studied. The results showed that food supply service increased, soil conservation service decreased, and water yield service increased first and then decreased during the study period. In terms of spatial distribution, food supply service presented "low-high-low-high" in the northwest-southeast direction, soil conservation service was concentrated in high and low values, and water yield service was high in south and low in north. There were trade-off relationships between food supply and soil conservation, and between food supply and water yield. There was synergistic relationship between soil conservation and water yield. Moreover, the relationship between food supply and soil conservation showed a spatial pattern of synergy in northern but trade-off in southern region. There was a clear spatial trade-off between food supply and water yield, and from north to south the relationship between soil conservation and water yield existed synergy-tradeoff-synergy differentiation, like a "sandwich". Among different land use types, there was a significant synergy between cultivated land and food supply, garden land and soil conservation, water area and water yield, but trade-off relationships between construction land and three services. The relationship between food supply and soil conservation and water yield was mainly trade-off in different land use types. The relationship between soil conservation and water yield was synergy in cultivated land, garden land, grassland and construction land, but was trade-off in water and unused land. The hot spots of multiple ecosystem services in the Poyang Lake region were mainly in the eastern and sou-thern plain areas, with a decreasing trend.