The soft-bottom macrobenthos of North Carolina estuaries

摘要: The structure of macro infaunal (>0.5 mm sieve size) assemblages was examined in samples unconsolidated substrates collected during the summers 1994–1997 at 208 stations throughout North Carolina estuaries. Numerical classification (cluster analysis) resulted 14 distinct site groups that reflected discernible habitatrelated patterns species distributions. Multiple discriminant analysis, performed on synoptic abiotic variables (depth, salinity, dissolved oxygen, pH, percent silt-clay), showed separation related primarily to salinity. Percent silt-clay had a secondary influence sites within similar salinity zones. Species diversity among generally decreased with decreasing and increasing mud content sediment. Nodal analysis wide range constancy fidelity groups. Some dominated by euryhaline no particular affinity any one group. strongest affinities, as evidenced high values both fidelity, were displayed an assemblage oligochaetes, insect larvae, gammaridean amphipods, clamCorbicula fluminea tidal freshwater muds; haustoriid bivalveDonax variabilis, polychaeteParaonis fulgens, unidentified echinoids high-salinity outer Pamlico Sound near ocean inlets. A series impaired benthic polluted habitats emerged from cluster distinguishable other greater natural controlling factors (such sediment type) These results suggest interaction anthropogenic environmental is important defining these assemblages.