Species body size distribution patterns of marine benthic macrofauna assemblages from contrasting sediment types

Species body size spectra have been constructed for macrofauna assemblages from four sites with contrasting sediment granulometry and heterogeneity in and around Plymouth Sound. The number of species and species turnover (bet a diversity) were higher on coarse sediment. While the fauna were distinct between sites, the median geometric size-class was conservative (class 14; 0.153-0.305 mg dry blotted weight). Only one site had significantly lower h eterogeneity within the species size spectrum, yet this was the most hetero geneous sediment. As such, we were unable to reject the null hypothesis tha t species body size distribution patterns are conservative despite differen ces in sediment granulometry and heterogeneity.