Pomacea canaliculata is a major invasive snail species in freshwater ecosystems in southern China. Population outbreaks of this species threaten zoobenthic community structure and food web stability. However, the competitive mechanisms of invasive mollusks in zoobenthos communities remain poorly understood. Previous studies have neither systematically assessed the niche relationship between invasive mollusks and native zoobenthos communities nor identified the environmental driving mechanisms. To explore the niche, interspecific relationships, and relationships with environmental factors of the invasive community in the Jianghan Plain, 45 sampling sites were established (15 each in paddy fields, ditches, and lakes). Zoobenthos were collected using Peterson mud samplers and D-shaped nets, alongside corresponding water samples. The analysis of the P. canaliculata invasive community primarily focused on the dominant zoobenthos, niche width, morpho-functional group, niche overlap, and connection coefficient. The survey results revealed 65 species of zoobenthos, among which arthropods were the dominant taxon, accounting for 69.2% (45 species), and functional feeding taxa were dominated by predators and scrapers. The niche width of P. canaliculata varied significantly across different habitats. In paddy fields, P. canaliculata occupied a medium niche; in ditches, a narrow niche; and in lakes, a broad niche. In paddy fields, the niche overlap between P. canaliculata and major zoobenthos was low, with no species pairs exhibiting Oik > 0.6. In ditches, the niche overlap between P. canaliculata and major zoobenthos was relatively low, with only 28.57% of species pairs having Oik > 0.6. In lakes, the niche overlap between P. canaliculata and major zoobenthos was high, with 66.67% of species pairs having Oik > 0.6. The invasive community was positively associated overall (VR = 1.51, W = 45.23), and the species were relatively independent of one another. P. canaliculata was strongly associated with Diplonychus sp., Micronecta sp., Anisops sp., Aciagrion sp., Caridina sp., and Macrobrachium sp. According to environmental factor analyses, NH3-N, chemical oxygen demand, total nitrogen, and water temperature are the main environmental factors affecting the distribution of P. canaliculata. Overall, the results showed that invasion by P. canaliculata can affect the community structure and food web relationship of the zoobenthic community; however, the specific consequences and extent of the invasion are restricted by many factors.
