کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4426693 1309133 2009 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The origin of speciation: Trace metal kinetics over natural water/sediment interfaces and the consequences for bioaccumulation
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم محیط زیست شیمی زیست محیطی
پیش نمایش صفحه اول مقاله
The origin of speciation: Trace metal kinetics over natural water/sediment interfaces and the consequences for bioaccumulation
چکیده انگلیسی

The speciation of heavy metals was measured over a variety of natural and undisturbed water/sediment interfaces. Simultaneously, two benthic species (oligochaete Limnodrilus spp. and the midge Chironomus riparius) were exposed to these sediments. Under occurring redox conditions, free ion activities of trace metals Cd, Cu, Ni, Pb, and Zn were measured with a chelating exchange technique, while geochemical conditions (i.e., redox) remained in tact. Free ion activities were compared with total dissolved concentrations in pore waters and surface waters in order to relate speciation to bioaccumulation. Limnodrilus spp. and C. riparius have accumulation patterns that could be linked to time-dependent exposure concentrations, expressed as chemical speciation, in the surface water and the sediment's pore water. Concentrations of free metal ions in the overlying surface water, rather than in sediment pore water, proved to be the best predictor for uptake. For the first time, measurements are obtained from sediments without disturbing physical–chemical conditions and thus bioavailability, a major restriction of other studies so far.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Environmental Pollution - Volume 157, Issue 2, February 2009, Pages 519–527
نویسندگان
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