Abstract:

Investigating the distribution characteristics of landscape ecological risks in the Chaohu Lake watershed based on topographic gradients is crucial for formulating ecological risk avoidance measures and future development strategies in small watersheds. In this study, the landscape pattern index and ecological risk index were employed to illustrate the evolution mechanism of landscape patterns and ecological risks in the Chaohu Lake watershed. The topographic position index and distribution index were adopted to enhance geomorphological descriptions, facilitating the exploration of spatial and temporal variations in landscape patterns and ecological risks within the watershed. Findings reveal that the Chaohu Lake watershed is dominated by low-grade terrain. Within low- and medium-low-grade terrain areas, human activity distribution gradually intensifies, leading to landscape irregularity. Areas with lower risk grades exhibit greater adaptability to in high-gradient spaces, whereas high-risk areas are predominantly situated in low-grade terrain. Stable change is the overwhelmingly primary change pattern of landscape ecological risk grades. Future planning for the Chaohu Lake watershed requires tailored measures to improve water ecological environments, strictly adhere to ecological redlines, and prevent excessive expansion that could jeopardize ecological integrity.

Key words: landscape pattern, landscape ecological risk, topographic gradient effect, geo-information mapping, spatial and temporal variation characteristics, Chaohu watershed