Abstract:
To understand the water quality status and plankton community characteristics in the Huolin River Basin under the influence of different land-use structures and landscape patterns, water samples were collected from 20 monitoring sections in October 2023. Eight water quality parameters were measured, and plankton community characteristics were investigated. During the survey, 88 zooplankton species (4 categories) and 98 phytoplankton species (6 phyla) were identified. Rotifers dominated the zooplankton community, while Bacillariophyta and Chlorophyta constituted the primary phytoplankton groups. Land-use structures and landscape patterns significantly influenced water quality. Specifically, grassland and woodland effectively filtered and intercepted pollutants, with higher Largest Patch Index (LPI) values enhancing their water purification capacity. Conversely, construction land and cultivated land exerted negative effects on river water quality. These land-use structures and landscape configurations indirectly shaped plankton community characteristics by altering physicochemical water parameters. Key environmental factors affecting dominant zooplankton species abundance included: the proportion of grassland and cultivated land in the buffer zone, LPI, Shannon’s Diversity Index, as well as ammonia nitrogen and permanganate index in water. For dominant phytoplankton species, critical factors were the proportion of cultivated land, nitrate nitrogen, ammonia nitrogen, alkalinity, and dissolved oxygen. These findings provide a scientific basis for rational land-use planning and landscape pattern optimization in the Huolin River Basin, and offered essential data support for riverine ecological conservation and restoration.