What are the key biogeochemical processes that control metal speciation in sediments?
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The key biogeochemical processes that control metal speciation in sediments include solid-phase speciation, hydrodynamics, bioturbation, and biogeochemical transformations. Solid-phase speciation plays a critical role in determining the availability of trace metals in anoxic wetland soils and stream bed sediments . Hydrodynamics, such as flow forcing and sediment resuspension, can mobilize metal species from surficial sediments to pore water and overlying water . Bioturbation and bioirrigation by burrowing organisms increase sediment heterogeneity, oxygen delivery, and efflux of metals to pore water and overlying water . Bioturbation also enhances sediment destabilization and particle resuspension, leading to increased metal efflux following flow perturbations . These processes collectively influence metal speciation, solubility, and the development of concentration gradients at the sediment-water interface . Additionally, changes in sediment Eh (oxidation-reduction potential) and pH conditions can also affect metal speciation in sediments .
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27 Apr 2018 9 Citations | The paper does not provide specific information about the key biogeochemical processes that control metal speciation in sediments. |
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6 Citations | The paper does not provide information on the key biogeochemical processes that control metal speciation in sediments. |
| The paper does not provide information on the key biogeochemical processes that control metal speciation in sediments. |
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