Nunes M, Coelho J P, Cardoso P G, Pereira M E, Duarte A C, Pardal M A
IMAR - Institute of Marine Research, Zoology Department, University of Coimbra, Coimbra, Portugal.
Sci Total Environ. 2008 Nov 1;405(1-3):186-94. doi: 10.1016/j.scitotenv.2008.07.009. Epub 2008 Sep 2.
Mercury is a widely distributed environmental pollutant and a toxic element to all living organisms. This study represents an attempt to evaluate its correlation with the macrobenthic community structure in a temperate estuarine system, the Ria de Aveiro (Portugal). The macrobenthic community structure showed significant differences along the mercury gradient. Overall, the increase of mercury contamination was associated with reduced total abundance, lower species richness, and dominance of tolerant taxa. The polychaetes Hediste diversicolor and Alkmaria romijni, and the isopod Cyathura carinata were associated with high levels of mercury in sediment, while the bivalves Scrobicularia plana, Cerastoderma edule and Abra alba showed higher density in lesser contaminated sites. Furthermore, highly contaminated sites showed substantially lower abundances of surface-deposit feeders and herbivores, and higher abundances of subsurface-deposit feeders and omnivores. Salinity was also a significant factor affecting the community, being responsible for seasonal variations in the macrobenthic assemblages.
汞是一种广泛分布的环境污染物，对所有生物都是有毒元素。本研究旨在评估其与葡萄牙阿威罗里亚（Ria de Aveiro）温带河口系统大型底栖动物群落结构的相关性。大型底栖动物群落结构沿汞梯度呈现出显著差异。总体而言，汞污染的增加与总丰度降低、物种丰富度降低以及耐污类群的优势地位有关。多毛类的杂色沙蚕（Hediste diversicolor）和罗米尼阿尔克马虫（Alkmaria romijni），以及等足类的隆背似哲水蚤（Cyathura carinata）与沉积物中的高汞含量相关，而双壳类的扁平河篮蛤（Scrobicularia plana）、紫贻贝（Cerastoderma edule）和白樱蛤（Abra alba）在污染较轻的地点密度较高。此外，高度污染的地点表层沉积物摄食者和草食动物的丰度显著较低，而地下沉积物摄食者和杂食动物的丰度较高。盐度也是影响群落的一个重要因素，它导致大型底栖动物组合出现季节性变化。
