Comparative study of heavy metals concentration in topsoil of urban green space and agricultural land uses

Abstract

The main objective of this study was to determine the concentration of cadmium, chromium, copper, nickel, lead, and zinc in surface soils of two land uses including agricultural and urban green space in Semnan Province, Iran. For this purpose, the soil samples of 27 urban green space and 47 agricultural fields were collected and analyzed. The correlation coefficients, analysis of variance, principal component analysis, cluster analysis, and geoaccumulation index were utilized to compare the mean values in the two land uses and pinpoint the possible sources of contamination in the study area. The average contents of Cd, Cu, Cr, Ni, Pb, and Zn in green space soils were 0.1, 24.9, 78.7, 28.2, 22.1, and 82.1 mg/kg, respectively, while the mean concentrations of Cd, Cu, Cr, Ni, Pb, and Zn in agricultural soils were 0.3, 24.3, 83.7, 33.3, 18.1, and 80.4 mg/kg, respectively. The mean concentrations of lead, copper, and zinc were higher in urban green space in comparison with those of agricultural fields, while it was vice versa for chromium, cadmium, and nickel. In general, significant, but weak, correlations were observed between Zn with Pb (r = 0.53) and Cu (r = 0.61) and Ni with Cr (r = 0.55) and Cu(r = 0.51). The main sources of contamination turned out to be both natural and anthropogenic as the results of correlation coefficients, principal component analysis, and cluster analysis showed. That is to say, chromium and nickel had emanated from natural while the sources of cadmium, lead, and zinc could be attributed to anthropogenic activities. For the case of copper, both natural and anthropogenic activities were influential; however, the role of human activities was more effective. The results of contamination assessment showed that heavy metal contamination in agricultural land use was higher than green space indicating the role of human activities in this respect.

Potentially Toxic Element Content in Arid Agricultural Soils in South Iran

“…The PTE levels obtained in this studied were compared with data reported by other studies carried out for agricultural soils in Iran (Table 2). When compared with the results of previous studies in Iran e.g., [13,40,41,[43][44][45][46][47], average values are similar or lower to indicate by them, probably due to some of these studies were carried out near to industrial areas e.g., [40,41]. Results showed significant enrichment of Cr and Ni in studied agricultural lands, although with similar values as indicated by Doabi et al [13] for agricultural areas in Kermanshah province, Western Iran.…”

Assessment of soil heavy metal pollution in a former mining area - before and after the end of mining activities

“…Since 1997 till 2015, the average value of As, Hg, Zn, Cu, Co, Ni, Cr, Pb, and Cd decreased above (Banasová & Lackovičová 2004;Hronec et al 2008) with positive impact on the environmental situation within the study area. But due to the fact, that heavy metals are non-biodegradable, they remain accumulated in the soil for years (Mehrabi et al 2015;Mirzaei et al 2015).…”

Characterization of Heavy Metals in Soil as Affected by Different Land Uses in Northern Pakistan

“…Higher concentration of total Fe was found in the fallow land and the lower concentration was found 1). However, many studies indicated that farmlands usually exhibited significantly higher heavy metal contents compared to other land use types due to the continuous application of agrochemicals [30][31]. The heavy metal fractions in various land systems varied in order of fallow>pasture >crop>forest.…”