Soil contamination in the vicinity of the Dabaoshan Mine, Guangdong Province, China, was studied through determi- nation of total concentrations and chemical speciation of the toxic metals, Cu, Zn, Cd, and Pb, using i...Soil contamination in the vicinity of the Dabaoshan Mine, Guangdong Province, China, was studied through determi- nation of total concentrations and chemical speciation of the toxic metals, Cu, Zn, Cd, and Pb, using inductively coupled plasma mass spectrometry. The results showed that over the past decades, the environmental pollution was caused by a combination of Cu, Zn, Cd, and Pb, with tailings and acid mine drainage being the main pollution sources affecting soils. Significantly higher levels (P ≤ 0.05) of Cu, Zn, Cd, and Pb were found in the tailings as compared with paddy, garden, and control soils, with averages of 1486, 2516, 6.42, and 429 mg kg^-1, respectively. These metals were continuously dispersed downstream from the tallings and waste waters, and therefore their concentrations in the paddy soils were as high as 567, 1 140, 2.48, and 191 mg kg^-1, respectively, being significantly higher (P ≤ 0.05) as compared with those in the garden soils. The results of sequential extraction of the above metals from all the soil types showed that the residual fraction was the dominant form. However, the amounts of metals that were bound to Fe-Mn oxides and organic matter were relatively higher than those bound to carbonates or those that existed in exchangeable forms. As metals could be transformed from an inert state to an active state, the potential environmental risk due to these metals would increase with time.展开更多
A field experiment was conducted to study the effects of Pb, Cd, Cu, Zn and As coexisting in red soilon growth of rice (Oryza sativa L.), mung bean (Vigna rabiata (Linn.) Wilczek), alfalfa (Medicago sativaL.), slash p...A field experiment was conducted to study the effects of Pb, Cd, Cu, Zn and As coexisting in red soilon growth of rice (Oryza sativa L.), mung bean (Vigna rabiata (Linn.) Wilczek), alfalfa (Medicago sativaL.), slash pine (Pinus elliottii Engelm.) and aspen (Populus L.). Results showed that rice, mung bean andalfalfa were significantly innuenced by combined pollution of the heavy metals. The contents of Pb, cd andAs in rice grains greatly exceeded the National Standards for Food Hygiene of China. Heavy metals at ahigh concentration seriously retarded growth of mung bean and alfalfa, but not so obviously with slash pineand aspen. The composite index is suggested for evaluating the relativity of combined pollution witll heavymetals in soil.展开更多
The pot-culture method combined with chemical and statistical analyses was used to get basic data for determination of the food-security indexes related to combined pollution of Cr and phenol in soil-rice systems.Regr...The pot-culture method combined with chemical and statistical analyses was used to get basic data for determination of the food-security indexes related to combined pollution of Cr and phenol in soil-rice systems.Regression analyses according to the experimental result indicated that the critical concentrations of Cr andphenol in brown rice were 0.37 and 0.33 mg kg-1, respectively, under the condition of Cr-phenol combined pollution.展开更多
基金Project supported by the Guangdong Environmental Protection Bureau of China (No.2001-27)Guangdong Provincial Department of Science and Technology,China (No.2004A30308002)State Key Laboratory of Environment Geochemistry,Chinese Academy of Sciences
文摘Soil contamination in the vicinity of the Dabaoshan Mine, Guangdong Province, China, was studied through determi- nation of total concentrations and chemical speciation of the toxic metals, Cu, Zn, Cd, and Pb, using inductively coupled plasma mass spectrometry. The results showed that over the past decades, the environmental pollution was caused by a combination of Cu, Zn, Cd, and Pb, with tailings and acid mine drainage being the main pollution sources affecting soils. Significantly higher levels (P ≤ 0.05) of Cu, Zn, Cd, and Pb were found in the tailings as compared with paddy, garden, and control soils, with averages of 1486, 2516, 6.42, and 429 mg kg^-1, respectively. These metals were continuously dispersed downstream from the tallings and waste waters, and therefore their concentrations in the paddy soils were as high as 567, 1 140, 2.48, and 191 mg kg^-1, respectively, being significantly higher (P ≤ 0.05) as compared with those in the garden soils. The results of sequential extraction of the above metals from all the soil types showed that the residual fraction was the dominant form. However, the amounts of metals that were bound to Fe-Mn oxides and organic matter were relatively higher than those bound to carbonates or those that existed in exchangeable forms. As metals could be transformed from an inert state to an active state, the potential environmental risk due to these metals would increase with time.
文摘A field experiment was conducted to study the effects of Pb, Cd, Cu, Zn and As coexisting in red soilon growth of rice (Oryza sativa L.), mung bean (Vigna rabiata (Linn.) Wilczek), alfalfa (Medicago sativaL.), slash pine (Pinus elliottii Engelm.) and aspen (Populus L.). Results showed that rice, mung bean andalfalfa were significantly innuenced by combined pollution of the heavy metals. The contents of Pb, cd andAs in rice grains greatly exceeded the National Standards for Food Hygiene of China. Heavy metals at ahigh concentration seriously retarded growth of mung bean and alfalfa, but not so obviously with slash pineand aspen. The composite index is suggested for evaluating the relativity of combined pollution witll heavymetals in soil.
文摘The pot-culture method combined with chemical and statistical analyses was used to get basic data for determination of the food-security indexes related to combined pollution of Cr and phenol in soil-rice systems.Regression analyses according to the experimental result indicated that the critical concentrations of Cr andphenol in brown rice were 0.37 and 0.33 mg kg-1, respectively, under the condition of Cr-phenol combined pollution.