The Relationship Between Landscape Patterns and Nearshore Water Quality: A Case Study of Erhai Lake, Southwest China

Landscape patterns directly or indirectly affect lake water quality by regulating nutrient inputs, pollutant interception, hydrological processes, and ecological functions. Due to scale effects, the mechanisms through which landscape patterns influence nearshore lake water quality are extraordinarily complex. Based on 2017 water quality monitoring data from the nearshore area of Erhai Lake in southwestern China, this study employed redundancy analysis (RDA) and Pearson correlation analysis to investigate the relationship between nearshore water quality and landscape patterns at multiple spatial scales. Results indicated that: (1) RDA revealed that the landscape patterns within all buffer zones exhibit explanatory power for water quality variations. Pearson correlation analysis underscores that landscape composition exerts a stronger influence on water quality than landscape configuration. (2) Within the 500 m buffer zone, both landscape composition and configuration had an explanatory power exceeding 86% for RDA1. Pearson correlation analysis indicated that the effects of different landscape types and their proportions on water quality parameters varied with buffer zone. Meanwhile, the influence of landscape configuration on water quality parameters tended to weaken as the buffer scale increases. (3) Wetlands exhibited the most substantial positive influence on water quality parameters both within the 500 m buffer zone and beyond 3000 m. These findings contribute to a better understanding of how nearshore landscape patterns influence water quality and provide essential information for effective nearshore landscape planning and water quality management in Erhai Lake.