【目的】 云南省抚仙湖流域作为我国西南地区和珠江流域重要的生态屏障,是我国“两屏三带”生态安全格局的重要组成部分。抚仙湖流域景观格局和生态系统服务价值(ESV)的变化受到“四退三还”保护政策的影响,定量研究其发展演变规律,为流域景观的保护与规划提供参考。【方法】 选取2006—2021年“四退三还”保护政策实施前后抚仙湖流域的4期遥感影像进行景观分类,计算土地利用动态度、转移矩阵、景观格局指数,并基于当量因子法评估生态系统服务价值(ESV),运用SPSS对流域的ESV与景观格局指数进行相关性分析。【结果】 ①“四退三还”政策实施前,抚仙湖流域林地面积大量减少,建设用地持续扩展,水体面积减少;景观格局复杂化、破碎化,连通性减弱,同时流域ESV明显下降。“四退三还”政策实施后,抚仙湖流域林地面积显著增加,建设用地扩张速度明显减缓,水体缩减速度降低;景观格局破碎化程度降低,连通性增强;流域ESV显著增加。②抚仙湖流域ESV与景观格局之间存在明显联系,流域ESV总量与景观格局指数蔓延度(CONTAGE)显著正相关,与香浓多样性指数(SHDI)和香浓均匀度指数(SHEI)相关性较高且呈负相关。各单项生态系统服务价值中,供给服务与最大斑块指数(LPI)显著负相关;调节服务和支持服务与CONTAGE显著正相关,与SHDI和SHEI显著负相关;文化服务与CONTAGE显著正相关。【结论】 景观类型的剧烈变化引起景观类型之间的相互转移以及景观多样性、连通度等的变化,并改变了景观生态系统的结构和功能,同时也影响生态系统服务价值。未来研究中可聚焦其机制,为抚仙湖流域下一步的保护与管理提供参考。

【Objective】 Changes in landscape patterns and ecosystem service values (ESVs) in the Fuxian Lake basin are affected by the “Four Retreats and Three Returns” protection policy. Quantitatively understanding such changes can provide a reference for the protection of watershed landscapes. 【Method】 Four sets of remote sensing images taken from 2006 to 2021 (before and after the implementation of the “Four Retreats and Three Returns” protection policy) were selected for landscape classification, and the land use dynamics, transfer matrix and landscape pattern indices were calculated. The ESVs were evaluated using the equivalent factor method and the SPSS software package was used to analyze the correlations between the ESVs in the watershed and the landscape pattern indices. 【Result】 The results indicated that the forested and water system areas in the Fuxian Lake basin were small, while the construction land area was expanding before the implementation of the “Four Retreats and Three Returns” protection policy. The landscape pattern was also complicated and fragmented, with weak connectivity and low ESVs. After the policy was implemented, the forested area increased significantly, the expansion of construction land slowed significantly, and the rate of water system reduction decreased. The degree of fragmentation of the landscape pattern also decreased and the connectivity was enhanced. The ESVs in the basin increased significantly. (2) The ESVs in the Fuxian Lake basin were connected with the landscape pattern, and the total basin ESV was significantly positively correlated with CONTAGE and negatively correlated with SHDI and SHEI. Among the individual ESVs, supply services were significantly negatively correlated with LPI, regulation and support services were significantly positively correlated with CONTAGE and significantly negatively correlated with SHDI and SHEI, and cultural services were significantly positively correlated with CONTAGE. 【Conclusion】 Future studies should focus on the mechanism behind these changes and provide a reference for the next step in protecting and managing the Fuxian Lake basin.