Abstract：
Reservoirs are a crucial form of water ecological infrastructure that offers a wide range of ecosystem services. The impact of reservoir construction on land use and landscape patterns is a matter of considerable importance. However, the specific effects of local-scale reservoir development on water system landscape patterns have not been comprehensively investigated. The Changshou district of Chongqing, located in southwest China and having an artificial lake system primarily composed of reservoirs, is an excellent example of examining the effects of human activities on the landscape patterns of water systems. This research reconstructed the historical evolution of reservoirs and rivers in Changshou District by historical maps and remote sensing data over seven decades from 1950 to 2020. On this basis, the landscape pattern metrics and graph-theoretical metrics of water systems in four crucial years, 1950, 1960, 1990, and 2020, were analyzed. The results indicate that from 1950 to 2020, the reservoir area in Changshou District increased by 64.195 km2, while the river area decreased by 7.297 km2; the two periods with the highest reservoir construction intensity were the 1950s and the 1970s to 1980s, when the reservoir area increased by 58.456 km2 and 3.089 km2, respectively; the construction of reservoirs diminished the connectivity of water systems and increased their fragmentation, dispersion, and edge complexity, but had little effect on their concentration and shape complexity. The findings can be applied to the optimization of water system patterns at the local level, the management of reservoir groups, the decision-making of water ecological infrastructure, and ecological effect studies of artificial lakes.
摘要：
水库是水生态基础设施的重要形式，可提供广泛的生态系统服务。水库建设对土地利用和景观格局的影响是一个相当重要的问题。然而,尚未全面研究局部尺度水库开发对水系统景观格局的具体影响。重庆市长寿区,位于中国西南部，拥有一个主要由水库组成的人工湖系统，是研究人类活动对水系统景观格局影响的一个很好的例子。本研究通过1950年至2020年七十年的历史地图和遥感数据，重建了长寿区水库和河流的历史演变。在此基础上,四个关键年份水系统的景观格局指标和图论指标，对1950年、1960年、1990年和2020年进行了分析。结果表明,1950~2020年,长寿区水库面积增加64.195km2,河流面积减少7.297km2;水库建设强度最高的两个时期分别为20世纪50年代和70~80年代,当水库面积分别增加58.456km2和3.089km2时；水库的建设减少了水系统的连通性，增加了水系统的破碎性，色散，和边缘复杂性，但对它们的浓度和形状复杂性影响不大。研究结果可应用于当地水系统模式的优化，水库群的管理，水生态基础设施的决策，人工湖的生态效应研究。
