Using watershed characteristics, sediment, and tissue of resident mollusks to identify potential sources of trace elements to streams in a complex agricultural landscape

Abstract

Trace elements used in animal feed additives can be introduced to aquatic environments through application of manures from animal feeding operations to agricultural land as fertilizer. The use of poultry feed additives containing arsenic (As) is of particular concern in the Shenandoah River watershed (Virginia, USA), an agricultural landscape with a high density of poultry operations. This study investigated the relationship between watershed characteristics of Shenandoah River tributaries and trace element concentrations in streambed sediment and tissue of resident mollusks, including: Asian clams (Corbicula fluminea), which are commonly used biomonitors, and pleurocerid snails (Leptoxis carinata), which are generally understudied. Results failed to support the primary hypothesis of a predictive relationship between watershed densities of poultry operations and As concentrations in sediment and mollusk tissue. However, there were statistical relationships between land use in tributary watersheds and other trace elements in sediment (Cu, Mn, Pb, Zn) and tissue (Cd, Hg, Pb). Principal components analysis of the sediment data suggested a possible geologic source of As at some sites. Tissue concentrations of As were significantly higher in snails than in clams, but clams accumulated higher concentrations of other trace elements (Cd, Cr, Hg, Pb, Se). Snails may be useful biomonitors of environmental As, but appear to be less suitable than clams for studies of landscape sources of other trace elements.

Migration Features and Regularities of Heavy Metals Transformation in Fresh and Marine Ecosystems (Peter the Great Bay and Lake Khanka)

“…A majority of all pollutants, including HMs, enter water bodies with continental runoff and subsequent migration along trophic chains [1,2]. Here, some HMs are characterized by biomagnification in living organisms [3][4][5], while most HMs do not accumulate there [6,7] and ultimately are deposited in sea bottom sediments [8,9] of freshwater basins (ponds, lakes) and coastal sea areas.…”

The influence of the landscape structure within buffer zones, catchment land use and instream environmental variables on mollusc communities in a medium‐sized lowland river

“…The types of catchment land use are usually correlated with the physical and chemical parameters of the water and bottom sediments, which in turn affect the structure of lotic macroinvertebrate communities, including molluscs (Sponseller et al 2001;Erba et al 2015;Valle Junior et al 2015). For example, Ciparis et al (2012) found statistically significant relationships between catchment land use and the concentrations of heavy metals in the bottom sediments and Mollusca tissues.…”