Assessment of Heavy Metal Contamination in the Surrounding Soils and Surface Sediments in Xiawangang River, Qingshuitang District

Abstract

Xiawanggang River region is considered to be one of the most polluted areas in China due to its huge amount discharge of pollutants and accumulation for years. As it is one branch of Xiang River and the area downstream is Changsha city, the capital of Hunan Province, the ecological niche of Xiawangang River is very important. The pollution treatment in this area was emphasized in the Twelfth Five-Year Plan of Chinese government for Xiang River Water Environmental Pollution Control. In order to assess the heavy metal pollution and provide the base information in this region for The Twelfth Five-Year Plan, contents and fractions of four heavy metals (Cd, Cu, Pb and Zn) covering both sediments and soils were analyzed to study their contamination state. Three different indexes were applied to assess the pollution extent. The results showed this area was severely polluted by the four heavy metals, and the total concentrations exceeded the Chinese environmental quality standard for soil, grade III, especially for Cd. Moreover, Cd, rated as being in high risk, had a high mobility as its great contents of exchangeable and carbonates fractions in spite of its relative low content. Regression analysis revealed clay could well explain the regression equation for Cd, Cu and Zn while pH and sand could significantly interpret the regression equation for Pb. Moreover, there was a significant correlation between Non-residual fraction and Igeo for all the four metals. Correlation analysis showed four metals maybe had similar pollution sources.

Spatial Distribution and Mobility Assessment of Carcinogenic Heavy Metals in Soil Profiles Using Geostatistics and Random Forest, Boruta Algorithm

“…The metal mobility factor describes the possible movement of the selected heavy metals out of the soil profiles [49].…”

Assessment of Heavy Metal Contamination from Sediment and Soil in the Riparian Zone China’s Three Gorges Reservoir

“…fertilizer, pesticides, and herbicides) [16,17]. On the other hand, correlation analysis showed that heavy metals have significantly correlated each other except for Cr ( Table 4), suggesting that they might have similar pollution sources [32,33]. Moreover, the nutrient is significantly positively related to heavy metals (except Cr) ( Table 4), suggesting that enrichment of the nutrient may be a reason for richer heavy metals in sediment of the riparian zone in the TGR.…”

Response of rhizosphere microbial community structure and diversity to heavy metal co-pollution in arable soil

“…Due to industrial structure and historical reasons, environmental pollution of Qingshuitang District was very severe, making it one of the most serious areas of national environmental issues (Jiang et al 2013). Industries' wastewater was discharged into Xiawangang River, which was used for agricultural irrigation of surrounding farmlands; thus, it would lead to pollutant entering into soil and crops.…”