A COMMUNITY-LEVEL SEDIMENT BIOASSAY APPLIED TO AN ESTUARINE HEAVY-METAL GRADIENT

A simple laboratory microcosm system, previously used as a community l evel sediment bioassay for laboratory contaminated sediments, has been used for testing contaminated field sediments. Meiobenthic communitie s from the Lynher Estuary were incubated with defaunated sediment coll ected from the Fal Estuary system where a gradient of heavy metal conc entrations is reflected in meiofaunal community structure. In the micr ocosms changes in nematode community structure were related to sedimen t metal concentrations. These changes in community structure were simi lar to those previously observed between creeks in the Fal Estuary sys tem indicating that an experimental microcosm approach can be useful b oth as a sediment bioassay and in the validation of conclusions drawn from field surveys. Copyright (C) 1996 Elsevier Science Ltd.