Abstract:It is of great significance to study the impact of land use on macrobenthic communities for watershed land use planning revision and river ecological restoration. Taking the Babian River Basin in the upper reaches of the Red River as research area, the status of macrobenthic communities was investigated. Twenty land use indicators in 4 aspects including composition, allocation, diversity and hydrological distance based on upper catchment area of 37 sampling points were calculated to analyze the impacts of different land use patterns on macrobenthic communities. A total of 25 macrobenthic taxa were identified in this survey, of which aquatic insects accounted for 72% of the total. The main feeding functional groups were predators (PR), scrapers (SC), and gather collectors (GC). The impacts of urban land and woodland on macrobenthic communities were dominant, while the impact of agricultural land was relatively small in the Babian River Basin. The key land use indicators affecting the macrobenthic communities were the percentage of urban land (3PLA), the largest patch index of urban land (3LPI), the aggregation index of urban land (3AI), the flow length of urban land (3FLOW), the largest patch index of woodland (1LPI), and the landscape shape index of woodland (1LSI). Land use composition, allocation and hydrological distance were the main factors affecting macrobenthic communities in the Baibian River Basin, while land use diversity had little effect on macrobenthic community. The species density and diversity of macrobenthos showed negative correlations with 3PLA, 3LPI, 3AI, 3FLOW and 1LSI, while positive correlations with 1LPI. The clean species, such as Ephemeridae and Heptaglidae, increased with increasing of 1LPI. There were significantly negative correlations between the urban indexes and the density of SC and SH (Shredders), but no significant correlations between the urban indexes with other functional groups. SC and SH were sensitive to water quality and environmental conditions, however, GC were more tolerant of human interference. 1LPI was positively correlated with the density of SC and FC (Filter Collectors), but negatively correlated with the density of PR and GC. SC and FC had higher demands on habitat integrity, while GC and PR were more adaptive to human disturbance and fragmented habitat. On the one hand, with the increase of urban land use, the complexity of boundaries, and the degree of aggregation, the density and species diversity of macrobenthos in the study area decreased. On the other hand, as the integrity of woodland decreased, the species evenness of macrobenthos also decreased. The relationship between land use and macrobenthic species diversity and functional group diversity is not completely consistent, such as 1LSI and 3FLOW are negatively correlated with species diversity, but are positively correlated with functional group diversity. More in-depth researches are needed to investigate the impacts of land use on species, functional groups and communities at different scales.