Investigation and Analysis of River Habitat and Construction of Evaluation Model in Liaohe Irrigation District

This study focuses on the river habitat in the Liaohe irrigation district of northwest Jiangxi Province as the research scope, aiming to develop an evaluation index system and application model for large-scale irrigation districts. The assessment system of river habitat quality in the Liaohe irrigation district was screened using bibliometrics and analytic hierarchy process, and the river habitat degradation index and the index of river habitat quality were created based on the examination and analysis of the water environment and riparian habitat in the irrigation district. The findings demonstrated the geographical statistical significance of river water quality, riparian vegetation, economic structure, land use, riverbed substrate and other factors. The average habitat value among the 32 reaches that were evaluated was 2.54, with a range of 1.37 to 3.92. Among them, 28.13% had medium habitat quality, 21.88% had poor habitat quality, and 25% of the river reaches had exceptional habitat quality. According to the statistical findings, river habitats were distributed spatially as follows: upstream section ＞ middle section ＞ downstream section. Jing’an area ＞ Fengxin area ＞ Anyi area; countryside area ＞ agricultural area ＞ village area ＞ urban area.According to the river habitat degradation index, 31.25% of the river reach was clearly impacted by human activity. The quality of the habitat in rivers was significantly correlated negatively with habitat deterioration. Between 2000 and 2020, the irrigated area’s river habitat quality first declined and then progressively improved. The impact of human activity on the Liaohe irrigation district are becoming more and more evident, exhibiting the traits of the conversion of forested and farmed land into water areas and construction sites.