Benthic food web in lakes is generally supported by autochthonous primary production,and by terrestrial detritus derived from the surrounding catchment.Several studies have highlighted the importance of allochthonous input,but the effects of subsidy of that carbon source are not well understood in floodplain lakes of wetland,especially when thousands of herbivorous migrated waterfowl winter in that area and the water level is deceding.With stable isotope signatures(δ13C and δ15N)of four primary food sources and aquatic consumers,we used SIAR model to identify the relative importance of different production sources supporting the macroinvertebrate food web in a floodplain sublake of wetlands in Lake Poyang during the late dry season.Our data showed that Carex spp.was the predominant primary food source,potentially contributing 35%~53%organic carbon to the biomass of aquatic consumers in the sublake of wetlands,although its C:N ratio was much lower than other sources.For most of macroinvertebrate species,phytoplankton,and possibly particulate organic matter in the seston,were the other major carbon sources that they utilized.However,we did not find benthic algae or Vallisneria natans as thought to be important food sources for benthic primary consumers due to their low biomass during the cold and low water period.Our findings underpin the importance of allochthonous carbon sources,and further provide a view that migratory waterfowl may facilitate those subsidize which can support the biomass and productivity of consumer taxa in wetlands of Lake Poyang when availability of food sources is limited.