Study on River Health Assessment of Typical River Segments in the Xiang River Basin

River health assessment is an important method of understanding the state of a river and is fundamental to the sustainable development of river ecosystems. Traditional river health assessment frameworks primarily rely on panel data, such as monitoring points and statistical records, for evaluation, with indicators and data sources predominantly drawn from these sources. However, this type of data often reflects information from specific sections of the river, localised areas or survey points, and may lack the spatial data required to represent the river as a whole and its associated regions. More effective integration of panel and remote sensing data can provide a more comprehensive evaluation and a more accurate reflection of the actual health status of rivers. In this study, three river health assessment frameworks were applied to the Changsha section of the Xiangjiang River Basin (XRB) respectively based on panel data, remote sensing data, and a coupled approach integrating both types of data. A comparative analysis was conducted to evaluate the health of the Changsha section of the river across five dimensions: water quality, quantity, biology, physical structure and social services. This analysis yielded specific recommendations. The results show that: ①The river health assessment scores for the Changsha section of the XRB were 84.49, 75.73 and 80.29 under the panel-based, remote sensing-based and coupled frameworks, respectively. Different frameworks yielded different results, as approaches relying on either panel or remote sensing data alone may over- or underestimate the actual river health status. The coupled framework, which synthesises both panel and remote sensing data, is likely to provide a more balanced assessment.② Under the coupled assessment framework, the overall health status of the Changsha section of the XRB is rated as healthy, while certain river segments, localised areas or specific indicators remain sub-healthy or unhealthy. The primary factors influencing river health in the study area include water transparency, algal biomass (as indicated by chlorophyll-a concentration), the rate of wetland change, the fish retention index and the types of riparian land use. Among these, an unreasonable spatial configuration of riparian land use may be a key constraint. Therefore, when managing river health in the Changsha section of the Xiangjiang River, particular attention should be paid to the aforementioned indicators and associated health issues. The findings of this study provide insights into the selection of assessment indicators for river health studies and offer a reference for the management and planning of river health in this region in the future.