题目: Detection of terrigenous and marine organic matter flow into a eutrophic semi-enclosed bay by δ13C and δ15N of intertidal macrobenthos and basal food sources

作者: Iman Arbi, Songlin Liu, Jingping Zhang, YunchaoWu, Xiaoping Huang*

刊物: Science of The Total Environment

年卷期页: 2017,613-614:847-860

摘要：The pathways of terrigenous and marine organic matter originating into Daya Bay intertidal habitats were investigated using carbon and nitrogen stable isotope analyses. Spatiotemporal (sites, seasons and tidal levels) variationsin isotopic ratios of basal food sources andmacrobenthic consumers, and also the contribution of sources to the diet of representative species and the whole macrobenthic biomass were estimated using Isosource mixing model. Results showed the anthropogenic impacts on benthic and pelagic organic matter as well as macrobenthos, dependingon the spatial and temporal scales. Macrobenthic trophic structure was affected by mariculture and nuclear power plants in the dry season (winter), and the allochthonous sources i.e. industrial and urban sewage in flood season (summer).Microphytobenthos dominated the sediment organicmatter pool and macrobenthic diet,while the trophic importance of mangrove leaf litter for intertidal macrobenthic communities was low. However, mangroves showed their indirect effects on the variations in macrobenthic trophic function across tidal levels. The isotopic ratios of benthic food sources and common taxa varied significantly among the tidal levels of the mangrove-lined ecosystem. In addition, pooling the macrobenthic taxa based on their feeding guild and also biomass confirmed the causes and effects for variations in organic matter composition and flow indicated by representative species in the study area. Therefore, using feeding guild and biomass as the indicators of the macrobenthic trophic function is suggested as well as the tidal level spatial scale in the heterogeneous intertidal ecosystems for data analyses and sampling design of intertidal macrobenthic food web modeling.