Impacts of land use on benthic invertebrate diversity in the East River in China

Land use change and aquatic habitat degradation have important implications for lotic biodiversity because these anthropogenic disturbancespose severe threats to river ecosystems. This is evident in the Pearl River Delta, southern China, where rapid population growth, economic development and urbanization have been associated with changes to streams and rivers caused by pollution, sand dredging, dam construction, and over-fishing. However, there are limited data on the impacts of these threats to benthic invertebrate diversity. We examined human impacts on the East River (Dong Jiang) tributary of the Pearl River, a major source of water supply for Hong Kong and Guangdong Province in China. We hypothesized that increased disturbance intensity in river channel would significantly reduce taxon richness and affect the structure of benthic communities. We used total impervious area (TIA, % of total urban and rural areas within a catchment) for measuring land-use disturbance at 11 sites along the East River. Benthic invertebrates were sampled at each site. Water Quality Index was calculated from 7 water-quality parameters to indicate water quality condition