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Abstract Land use change can result in variations in ecosystem services (ESs) and their relationships. Studying the temporal dynamics of ESs and their relationships can support scenario analyses that provide the theoretical basis for policy decisions and regional ecosystem management. Previous studies have revealed the trade-offs between two ESs on multiple scales, while the trade-offs between multiple ESs require further analysis. Furthermore, trade-offs are rarely considered in scenario constructions, which weakens the ability of scenarios to inform land use policy. In this study, the InVEST model was applied to assess carbon sequestration, habitat quality, nutrient retention, sediment retention and seasonal water yield at five-year intervals from 1990 to 2015 and to construct five simulated scenarios that represented different ecological restoration and land reclamation policies. The results indicated that the Grain for Green Project (GFGP) increased all ESs, with seasonal water yield increasing by approximately 1.29 times above the initial stage. However, decreasing cropland area reduced the correlations between ESs both in trade-offs and synergies. Among all scenarios studied, the Returning Cropland to Grassland trade-off scenario had the maximum effect, while the natural succession to shrubland scenario had a minimum effect at the pixel level. Except for the land reclamation scenario, the overall ES benefits in the other scenarios exceeded the benefits received in 2015. Given the extent of watershed areas impacted by different overall ES benefit and trade-off situations, the Returning Cropland to Grassland scenario appears to best reduce the impacts of the worst situation compared to 2015, reducing the negative impacts by 22.6%. We suggest that scenarios that combine both overall ESs values and their trade-offs can support more effective and efficient land use decisions. Graphic abstract Unlabelled Image Highlights • We evaluated five regulating ESs and simulate five scenarios using the InVEST model. • Seasonal water yield showed a distinct increase after the GFGP was implemented. • Increased ESs and decreased cropland reduce correlations among them after 2000. • The Returning Cropland to Grassland scenario is optimal for future land use. [ABSTRACT FROM AUTHOR]

Abstract: The rapid economic growth in China has caused ever-increasing pollution and gradual deterioration of surface water quality over the whole territory of China since 1978. Along with it, there have been 130 environmental protection policies publicized and enacted. Unfortunately, even though these contradictory phenomena have coexisted for almost three decades, the cause analysis and the effective evaluation of policy measures are still rare. The Jiaxing region, a lowland located at the Taihu Lake watershed, is a typical representative of this dilemma and was proposed as a case study area for an assessment on the effectiveness of the environmental policy measures mentioned above. The pollutant loads originating from point pollution sources were discharged into rivers at fixed in-stream sites, while pollutant loads from non-point pollution sources in rural areas were assumed to be rushed into rivers by stormwater runoff. The environmental policy measures concerning water quality in the Jiaxing region were specified quantitatively as parameters for estimating the variation of pollutant loads. The base case and other three cases with the effects of policy measures were then simulated by the surface water quality models. The results show that a significant improvement of the surface water quality can be achieved by controlling the non-point pollution in rural areas and the point pollution over the whole area, if the water protection policies are sustainable and executed completely, and if the local government is active in their administrative, supervising and educational responsibilities and the farmers assume voluntary activities on rural pollution control. [Copyright &y& Elsevier]