【目的】千岛湖流域是长江三角洲重要的水源地和生态屏障区,研究其水源供给服务对长江三角洲生态保护和社会经济高质量可持续发展有着重要的意义。【方法】基于InVEST模型对千岛湖流域近30年的产水量进行量化,并通过情景分析法和地理探测器探究其时空变化特征以及空间分异的主要影响因子。【结果】1995-2019年,千岛湖流域产水量与降水量的年际变化具有一致性,表现为前期大幅度减小后明显增大再略微减小的波动变化趋势,空间分布格局变化不大, 产水高值区主要集中在流域西部,低值区则集中在流域东部湖区范围内;不同土地利用类型中,建筑用地的平均产水量最高,草地次之,林地和水体的平均产水量最低;气候变化对产水量的影响较为显著,土地利用变化对产水量的影响较低;实际蒸散量是产水量空间分布格局的主要驱动因子,土地利用类型次之,实际蒸散量与降水的交互作用最为显著。【结论】流域产水量是气候、土地利用类型等多种因子共同作用的结果,在未来的生态建设和环境保护中,需要综合考虑地形、气候和人类活动的变化对千岛湖流域产水服务的影响。

【Objective】The Thousand-Island Lake basin is an important water conservation and ecological barrier area in the Yangtze River Delta. Thus, the study of water supply services is of great significance to ecological protection and high-quality sustainable development of the social economy. 【Method】The water yield of the Thousand-Island Lake basin was quantified over a six-year period: 1995, 2000, 2005, 2010, 2015 and 2019 based on the InVEST model, and water yield spatio-temporal variations and influencing factors were explored using the scenario and geodetector analyses.【Result】From 1995 to 2019, water yield inter-annual variations in the Thousand-Island Lake basin was consistent with precipitation trends; that is the water yield decreased significantly from 1995 to 2005, increased significantly from 2005 to 2015, and showed a subsequent marginal decrease from 2015 to 2019. Spatial distribution patterns showed little variation over the study period; however, patterns were high in the west of the basin and low in the basin’s eastern lake. The average water yield of buildings was higher than that of other land use types, followed by grasslands and woodland; water bodies had the lowest average water yield. Precipitation had a stronger effect on water yield than that of land use changes, which was significant. Actual evapotranspiration was the main driving factor of water spatial patterns, followed by land use types. The interaction between actual evapotranspiration and rainfall was the most significant than others. 【Conclusion】The water yield is the result of a combination of factors including climate and land use types. For the future ecological construction and environmental protection, the impact of terrain, climate, and human activities on water yield services must be considered and comprehensively studied.