Duquesne Sabine, Newton Lyn C, Giusti Lorenzo, Marriott Susan B, Stärk Hans-Joachim, Bird David J
Department of Chemical Ecotoxicology, UFZ Centre for Environmental Research, D-04318 Leipzig, Germany.
Environ Pollut. 2006 Sep;143(2):187-96. doi: 10.1016/j.envpol.2005.12.002. Epub 2006 Feb 7.
Levels of heavy-metals (Cd, Cu, Cr, Ni, Pb and Zn) in suspended particulate and in surface and subsurface sediments were determined at seven locations in the Severn Estuary and Bristol Channel. Sediment metal concentrations were highest at sites close to industrial centres but levels have decreased significantly over the last 30 years so that they are now close to, or meet, environmental quality guidelines. The greatest metal concentrations in deposited sediments were usually associated with the finest particulates at locations with muddy sediments, but this was not always true at sites with predominantly sandy sediments. The metals bound to suspended particulates at all sites were remarkably consistent, presumably reflecting the mixing capacity of this macro-tidal estuary. The re-exposure of older, more contaminated sediments could explain the observed differences between deposited and suspended material. Sediment redistribution due to strong seasonal currents might also explain the differences between winter and summer samples.
在塞文河口和布里斯托尔海峡的七个地点，测定了悬浮颗粒物以及表层和次表层沉积物中的重金属（镉、铜、铬、镍、铅和锌）含量。沉积物中的金属浓度在靠近工业中心的地点最高，但在过去30年里已显著下降，以至于现在已接近或符合环境质量准则。沉积沉积物中最高的金属浓度通常与泥质沉积物地点的最细颗粒有关，但在以沙质沉积物为主的地点并非总是如此。所有地点与悬浮颗粒物结合的金属含量非常一致，大概反映了这个强潮河口的混合能力。较老的、污染更严重的沉积物再次暴露可能解释了沉积物质和悬浮物质之间观察到的差异。由于强烈的季节性水流导致的沉积物重新分布也可能解释冬季和夏季样本之间的差异。
