McGee Beth L, Pinkney Alfred E, Velinsky David J, Ashley Jeffrey T F, Fisher Daniel J, Ferrington Leonard C, Norberg-King Teresa J
US Fish and Wildlife Service, Chesapeake Bay, Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401, USA.
Environ Monit Assess. 2009 Sep;156(1-4):51-67. doi: 10.1007/s10661-008-0462-8. Epub 2008 Aug 2.
The Sediment Quality Triad (SQT) consists of complementary measures of sediment chemistry, benthic community structure, and sediment toxicity. We applied the SQT at 20 stations in the tidal portion of the Anacostia River from Bladensburg, MD to Washington, DC to establish a baseline of conditions to evaluate the effects of management actions. Sediment toxicity was assessed using 10-day survival and growth tests with the freshwater amphipod, Hyalella azteca and the midge, Chironomus dilutus. Triplicate grabs were taken at each station for benthic community analysis and the Benthic Index of Biotic Integrity (B-IBI) was used to interpret the data. Only one station, #92, exhibited toxicity related to sediment contamination. Sediments from this station significantly inhibited growth of both test species, had the highest concentrations of contaminants, and had a degraded benthic community, indicated by a B-IBI of less than 3. Additional sediment from this station was tested and sediment toxicity identification evaluation (TIE) procedures tentatively characterized organic compounds as the cause of toxicity. Overall, forty percent of the stations were classified as degraded by the B-IBI. However, qualitative and quantitative comparisons with sediment quality benchmarks indicated no clear relationship between benthic community health and contaminant concentrations. This study provides a baseline for assessing the effectiveness of management actions in the Anacostia River.
沉积物质量三元组（SQT）由沉积物化学、底栖生物群落结构和沉积物毒性的互补测量方法组成。我们在从马里兰州布莱登斯堡到华盛顿特区的阿纳科斯蒂亚河潮汐段的20个站点应用了SQT，以建立一个条件基线，用于评估管理行动的效果。使用淡水双足虾（阿氏摇蚊）和摇蚊（直突摇蚊）进行为期10天的生存和生长测试来评估沉积物毒性。在每个站点采集三份抓斗样本用于底栖生物群落分析，并使用生物完整性底栖指数（B-IBI）来解释数据。只有一个站点（92号）表现出与沉积物污染相关的毒性。该站点的沉积物显著抑制了两种测试物种的生长，污染物浓度最高，底栖生物群落退化，B-IBI小于3表明了这一点。对该站点的额外沉积物进行了测试，沉积物毒性鉴定评估（TIE）程序初步将有机化合物确定为毒性原因。总体而言，40%的站点被B-IBI归类为退化站点。然而，与沉积物质量基准的定性和定量比较表明，底栖生物群落健康与污染物浓度之间没有明确的关系。本研究为评估阿纳科斯蒂亚河管理行动的有效性提供了一个基线。
