Assessment, Distribution and Regional Geochemical Baseline of Heavy Metals in Soils of Densely Populated Area: A Case Study

Abstract

To understand the content, pollution, distribution and source and to establish a geochemical baseline of heavy metal elements in soil under the influence of high-density population, the concentrations of heavy metal elements Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Hg, Pb and Fe were determined in 23 soil samples in Suzhou University, and geo-accumulation index, enrichment factor, principal component analysis, spatial analysis and regression analysis were completed. The results showed the following: The elements Cu and As were slightly polluted, while the other heavy metal elements were not. The elements Cd, Cu, Ni and As in soils were mainly caused by agricultural activities of chemical fertilizer, whereas the elements Zn and Hg were impacted by the chemicals and batteries. The heavy metal elements in the north were lower than in the south of the campus, as a whole. The enrichment of elements Cu, As and Cd was caused by the east–west river on the campus, and the enrichment of the elements Mn, Ni and Zn was induced by the reservoir. Biochemical experiments and vehicle parking influenced the spatial enrichment of Cr, Co and Pb, while domestic waste led to the spatial differentiation of Hg concentrations. The regression curve between heavy metal elements and Fe was established, and the background values of the heavy metals Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Hg and Pb are 50.90, 489.37, 11.76, 37.74, 55.70, 58.22, 20.07, 0.09, 0.08 and 24.13 mg/kg, respectively.

Geochemical Baseline Establishment and Source-Oriented Ecological Risk Assessment of Heavy Metals in Lime Concretion Black Soil from a Typical Agricultural Area

“…In this study, Cr, Mn and Co in the surface soils show mean concentrations lower than values characterizing their respective background ( Table 2 ), indicating that these metals are lacking obvious artificial sources, mostly controlled by parent materials. This result is consistent with that of the previous small-scale investigation conducted in a densely populated campus form the present study area [ 40 ]. Hence, the factor 2 could be considered as a natural source.…”

Physiological and Ultrastructural Changes in the Cattle Egret (Bubulcus Ibis), as Bio-Indicators of Soil Heavy Metal Pollution in Sharkia Province, Egypt

“…The concentrations of As, Cd, Pb, and Se in the soil samples from site "I" (urban site) have significantly higher levels compared to those from site "II" (rural site) during summer. The highest levels of metals in both sites were investigated in summer, this could be due to the different anthropogenic activities, transportation, atmospheric deposition, and application of fertilizers and pesticides [17] . Arsenic is a very toxic element that is widely distributed in the environment.…”

Characteristics and Risk Assessment of Soil Available Heavy Metal Pollution in Guangzhou Based on Multi Method Fusion

“…They observed slight pollution in Cu and As, primarily influenced by the reservoir. However, it's important to note that current evaluation methods come with certain limitations [13][14].While the Nemerow index can provide a comprehensive assessment of the overall multi-element pollution status of a region, reflecting the specific levels of pollution element content, it does not account for the differential impact of various element characteristics on the soil environment [15]. The potential ecological hazard index method takes into consideration the ecological, environmental, and toxicological effects of heavy metals, concentrating on the impact of elements with relatively high biological toxicity on the soil environment.…”