Studies on Organic Matter and Heavy Metals in Soils around the Coal-fired Power Plant in Jinsha

摘要

The concentrations of organic matter and heavy metals (H g, Cu, Pb, Zn, As and Cd) were analyzed in soils around the coal-fired power plant in Jinsha (Guizhou Province, China), and the ecological risks of these heavy metals were evaluated by using the ecological risk warning assessment. The results showed that the concentration of organic matter in soils was high with the average value up to 41.54 g/kg, which met the threshold limit for the concentration of organic matter at level 1. The concentration of organic matter in the study area was above the level of lack or the level of urgency. The results from the correlation analysis showed that there were correlations between organic matter and speciation of the heavy metals (except Pb). The results from the ecological risk warning assessment showed that the order for the risk probability of individual ecological risk index above the level of no alarm was： Hg > Cu = Pb > Zn > As = Cd. The comprehensive indices revealed that the probability was 15.62% for the sample locations at no alarm level, while the probabilities were 3.13 % , 40.63% , 21.87% and 18.75% for sample locations at the levels of early warning, light warning, medium warning and serious warning, respectively. The results indicated that the ecological environment in this area has been adversely affected to some extent, and thus the treatment of heavy metals pollution should be strengthened in the future.