四川盆地多重生态系统服务景观指数评价与服务簇识别

明确多重生态系统服务与生态系统服务簇的空间格局对于维持区域生态安全格局与可持续发展至关重要。在评估四川盆地2015年6种生态系统服务的基础上，计算了表征综合水平的多重生态系统服务景观指数；进而分析了生态系统服务间权衡与协同关系；并基于K-均值聚类法识别了研究区内生态系统服务簇的空间格局。研究结果表明：（1）研究区的多重生态系统服务景观指数平均值达到3.12，同时具有明显的空间分异性，整体上呈现出东南高西北低的空间分布格局，高值区主要分布于川东平行岭谷区，以林、草地为主的区域最高，城市建成区及其邻近地区最低。（2）6种生态系统服务空间异质性显著，且不同服务间协同与权衡关系并存，其中碳汇、生境质量和水土保持服务三者间的协同关系显著，碳汇、生境质量和水土保持服务与娱乐和粮食供给服务间的权衡关系均较强；产水服务与其他各项服务间的权衡与协同关系均较弱。（3）四川盆地可划分为文化旅游、食物供给、生态保育和多功能复合均衡型4种服务簇，其空间布局与内部结构分异明显。文化旅游型服务簇面积最小，面积占比为3.11%，主要分布于成都和重庆城镇及其周边地区，其提供多重生态系统服务功能的能力最弱；食物供给型服务簇主要位于成都平原、浅丘及部分河谷区域，面积约占36.23%；生态保育型服务簇主要分布于盆周山地，以林地为主导，其提供多重生态系统服务功能的能力最强，面积占比达22.61%；多功能复合均衡型服务簇分布最广，面积占比为38.04%，集中于川中、川东丘陵及平行岭谷槽谷区域。采取差异化优化措施有利于整体提升四川盆地生态系统服务能力，维护区域生态安全格局。

Evaluation of multiple ecosystem services landscape index and identification of ecosystem services bundles in Sichuan Basin

Understanding the spatial pattern of multiple ecosystem services and ecosystem services bundles is crucial for maintaining the regional ecological security pattern and sustainable development. Based on the assessment of six ecosystem services in Sichuan Basin in 2015, this paper evaluated multiple ecosystem services landscape index (MESLI) representing the comprehensive level of ecosystem services, and analyzed the trade-offs and synergies between ecosystem services in the Sichuan Basin. Then, K-means clustering method was applied to explore the spatial pattern of ecosystem service bundles, which was helpful to reveal the local characteristics of the ecological pattern of the Sichuan Basin. The results demonstrated that:(1) the average value of multiple ecosystem services landscape index in Sichuan Basin reached 3.12, and it had obviously spatial differentiation. The overall ability of the study area to provide multiple ecosystem services at the same time was high. It presented a spatial distribution pattern that high in the southeast and low in the northwest. The high value areas were mainly distributed in the parallel ridge valley area of eastern Sichuan, with the highest values area dominated by woodland and grassland, and the lowest values in the urban area and its adjacent areas. (2) Six ecosystem services in Sichuan Basin had significantly spatial heterogeneity. The synergy and trade-off relationships between ecosystem services existed simultaneously. Carbon storage, habitat quality, and soil conservation services showed a spatial distribution pattern of high around the basin and low in the central of the basin. Water yield service was higher in the southeast than in the northwest, and the highest in urban areas. High-value areas for food production service were concentrated in the Chengdu Plain and middle hilly area of Sichuan. High-value areas for entertainment service were mainly distributed in the main urban areas of Chengdu and Chongqing. There were significant synergies between carbon storage, habitat quality and soil conservation services, and prominent tradeoffs between the three services mentioned above and food production and entertainment services. The tradeoffs and synergies between water production service and other services were weak. (3) The Sichuan Basin could be divided into four service bundles:cultural tourism, food production, ecological conservation, and multi-functional balance with distinctly spatial distribution and internal structure. The cultural tourism bundle had the smallest area accounting for about 3.11% of the study area, which mainly distributed in the towns and surrounding areas of Chengdu and Chongqing, and its ability to provide multiple ecosystem services was the weakest. Food production service bundle accounted for about 36.23% of the study area which mainly located in the Chengdu Plain, shallow hills and some river valleys, with the cultivated land as the dominant type. The ecological conservation bundle was mainly distributed in the mountains around the basin, with forest land as the dominant type, which had the strongest ability to provide multiple ecosystem services. It covered 22.61% of the study area. Multi-functional balance bundle was the most widely distributed, accounting for about 38.04% of the study area. It mainly located in the valleys of the hills and parallel valleys in the central and eastern Sichuan, and was still dominated by cultivated land. Adopting differentiated optimization measures will be conducive to improving the overall ecosystem service level of the Sichuan Basin and maintaining the regional ecological security pattern.