Effect of Disturbance on the Hydro-environmental Factors and Macroinvertebrate Community in the Lijiang River

The impacts of stream disturbance caused by pleasured boat, and differences in seasonality on benthic macroinvertebrate communities, were evaluated in Lijiang River, China, October 2009 and April 2010. The environmental characteristic differed significantly between affected conditions and unaffected conditions. In wet period, the water temperature, conductivity and salinity after disturbance was significantly (p<0.01) lower than those without disturbance from pleasure-boat, the dissolved oxygen, pH, turbidity, velocity and total phosphorus had the opposite trend. In dry period, the water temperature after disturbance was significantly (p<0.01) higher than the water temperature without disturbance from pleasure-boat, the conductivity, salinity and COD had the opposite trend. In addition, the macroinvertebrate density, biomass and functional feeding groups differed between affected conditions and unaffected conditions.