Potential Sources of Heavy Metals in Sediments of an Urban‒Agricultural Watershed and Relationship with Land Use Using a Statistical Approach

Abstract

This study verified pollution levels through evaluation of the Sediment Quality Guidelines (SQGs), pollution load index (PLI), and potential ecological risk index (PERI) by analyzing the concentrations of heavy metals in sediments of an urban‒agricultural watershed in the Yeongsan River basin, South Korea. Statistical analyses were performed to determine the relationships between pollution levels and land use, and potential sources of pollution were identified. For spatial distributions, Pb, Zn, Cu, Cd, and Hg concentrations were highest at mid-upstream, but As, Cr, and Ni concentrations were similar at most sites. The polluted sites, which showed the potential toxicity toward benthic organisms in comparison to SQGs, were most frequently observed at mid-upstream. Moreover, PLI and PERI evaluations also confirmed levels of high anthropogenic pollution and the potential ecological risk at mid-upstream. The mid-upstream sites with high heavy metal pollutions showed high correlations with urban land use, which showed the highest distribution, implying a close relationship with anthropogenic impacts such as high population density and industrial complexes. Statistical analyses also confirmed that high heavy metal concentrations in the mid-upstream were closely related to urban land use. These findings suggest that urban areas are highly likely to cause anthropogenic heavy metal pollution in sediments as point or non-point sources such as domestic sewage and industrial wastewater flow into rivers.

An Assessment of the Heavy Metal Contamination, Risk, and Source Identification in the Sediments from the Liangtan River, China

“…The Pb contents in the sediments at sampling sites S2, S6, S9, S14, S15, and S19 were 1.77, 1.21, 1.87, 1.17, 4.73, and 1.40 times the environmental BGVs, respectively, making them significantly higher than the BGVs and indicating that the Pb in these sampling sites may be affected by human activities. Studies have shown that Pb is mainly emitted into the water and soil as a result of human activities such as the consumption of fossil fuels [39,59]. Fertilizers may also contain Pb [60].…”