Abstract
To analyze the concentration, spatial distribution patterns, and ecological risks of heavy metals (Cd, Cr, Pb, As, Cu, Ni and Co), 272 topsoil samples (0–20 cm) were collected from paddy fields in Fujian province in July 2017. The results revealed that the mean concentration of all heavy metals exceeded the background values in Fujian province, with the mean concentration of Cd being 5.20 times higher than its background. However, these concentrations of heavy metals were lower than their corresponding national standards (GB 15618-1995). Spatially, for Cd, the high concentration areas were located mainly in southeast of Sanming city and northeast of Quanzhou city. For Pb and As, the places of highest concentration were mainly in southeast of Quanzhou city and Zhangzhou city, and the main areas of high Ni concentration were distributed southeast of Nanping city. The geo-accumulation index ({I}_{geo}) of Cd and As were indicative of moderate contaminations, and the index of Co, Cu and Cr suggested that these were practically uncontaminated. The nemerow integrated pollution index ({P}_{n}) showed that the entire study area was prone to a low level of pollution, but at the county level, Yongcun county and Zhaoan county are in an warning line area of pollution. According to the potential ecological risk (RI), the ecological risk belongs to the low risk of paddy fields in Fujian province. However, Cd should be given attention ({E}_{r} = 25.09), as it contributed to the majority of potential ecological risks in Fujian province.
Highlights
To analyze the concentration, spatial distribution patterns, and ecological risks of heavy metals (Cd, Cr, Pb, As, Cu, Ni and Co), 272 topsoil samples (0–20 cm) were collected from paddy fields in Fujian province in July 2017
We found that Fujian province’s mean concentrations of heavy metals (Cd, Cr, Pb, As, Cu, Ni and Co) in paddy fields were greater than the background level in soils, and the max values of these metals were higher than the National Environmental Quality Standards for acidic agricultural soils (GB 15618-1995)
Compared with the pollution survey in the Yangtze river delta and the Pearl river d elta[1,17,18,19,20,26,35], we found that Fujian province contains a low level of heavy metal pollution, which is mainly due to the low degree of industrialization and the long-term development of the green economy in the region, such as construction of an ecological province in 2000
Summary
Spatial distribution patterns, and ecological risks of heavy metals (Cd, Cr, Pb, As, Cu, Ni and Co), 272 topsoil samples (0–20 cm) were collected from paddy fields in Fujian province in July 2017. To better manage the quality of the soil environment, it is necessary to strengthen the study of heavy metal pollution in paddy soils of a large regional scale, such as a provincial level. The evaluation of levels and risks for soil heavy metals pollution have been widely used to the methods of geo-accumulation index ( Igeo ), nemerow integrated pollution index ( Pn ) and potential ecological risk index ( RI ), which considers the lithology, maximum value, toxicity variance of the different heavy metals and the comprehensive effect of multiple contaminants, have been applied frequently[15,23,24]. The main objectives of the present study are (1) to determine the concentrations of heavy metals (Cd, Cr, Pb, As, Cu, Ni and Co) in paddy fields in Fujian province, (2) to evaluate the spatial distributions of heavy metals in paddy fields in Fujian province, and (3) to assess the soil heavy metal pollution levels and ecological risks in paddy fields in Fujian province
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
