Ecological monitoring and evaluation comparison of the Pearl River Source region in Yunnan based on model coupling

The Pearl River Basin, a pivotal river system in Southern China, traverses ecologically fragile zones including the Yunnan-Guizhou Plateau, port trading zones of the Beibu Gulf in Guangxi, and urban economic zones of the Pearl River Delta. So, regional ecological protection and monitoring are of profound practical significance for the entire river basin ecosystem. By incorporating the remote sensing-based ecological index (RSEI) model to evaluate regional ecological quality, this study proposed to strengthen data support for habitat quality (HQ) assessment in upper reaches of the Pearl River Basin, using the integrated valuation of ecosystem services and tradeoffs (InVEST) model. Through model coupling and methodological exploration, a comprehensive demonstration of dynamic trends in the habitat quality of Yunnan Pearl River Source region was presented. Through dynamic monitoring, model coupling, and comparative analysis, it can be concluded that the overall regional ecology of Yunnan Pearl River Source region is on a downward trend, while the specific trends and dominant ecological grades vary considerably. The underlying causes of these phenomena can be elaborated upon from multiple aspects, such as evaluation principles, parameter configurations, and calculation procedures. The coupling of different assessment models enhances the scientific rigor and persuasiveness of the evaluation results, offering scientific guidance for water conservation, ecological protection, as well as development and construction initiatives in the Pearl River Basin. Furthermore, the comparison of these models can stimulate further contemplation on the advancement of regional ecological assessment methodologies.