Comparison of macrobenthic communities between the invasive Spartina alterniflora and native Suaeda glauca habitats in the Yellow River Delta

Salt marsh habitats in estuaries play important roles in species compositions and macrobenthos abundances. Here, the macrobenthic communities and environmental conditions in two habitats, which are dominated by the invasive species Spartina alterniflora (SA) and native species Suaeda glauca (SG), in the Yellow River Delta (YRD) were studied to assess habitat function in four months of one year. The species diversity and abundance of macrobenthos in the SA habitat were much higher than those in the SG habitat. The taxonomic groups in the former showed significant changes over time and shifted from polychaeta (68%) in spring to mollusca (97%) in autumn, but in the latter, it was dominated by crustacea (63 similar to 86%), mollusca (1 similar to 25%) and polychaeta (9 similar to 13%), and only mollusca exhibited obvious month changes. The sediments in the SA habitat contained richer organic matter contents and exhibited higher Chl-alpha concentrations than those in the SG habitat, although the grain sizes were coarser in the SA habitat. Macrobenthos in the SA habitat displayed significant negative correlations with salinity and organic matter in four months. The results indicated that the taxonomic groups of macrobenthos in the SA habitat were simpler and more sensitive to environmental changes than those in the SG habitat. The effects of invasive SA on macrobenthos need to be further observed and explored, if it continues to expand in the YRD.