Surface runoff from rainfall event is an important indicator of metal mobility in soil, which may enhance non-point source contamination of soil. This study is designed to assess the mobility of soil-bound lead throug...Surface runoff from rainfall event is an important indicator of metal mobility in soil, which may enhance non-point source contamination of soil. This study is designed to assess the mobility of soil-bound lead through simulated rainfall runoff experiment and its spatial distribution within the vicinity of a berm at a major military shooting range. Contamination was more significant at the impact area of berm, indicating threefold increase in Pb (17,500 ± 3811 μg/g) within a space of ten years. However, the non-impact area (459 ± 147 μg/g) was less contaminated. Other metals (Cu, Cd, Cr, Ni and Zn) analyzed were about background levels except for Cu at impact area. The enrichment ratio of Pb in runoff sediments was mostly high for the 0.43 mm sediment fractions independent of rainfall condition. Principal component analysis (PCA) biplot showed strong correlation between spatial distributions of metals around the vicinity of the berm (farmlands behind the berm) with concentrations on the impact berm soil. Surface runoff simulated on impact area soil had high concentrations of Pb (40.4 - 65.6 μg/mL) which could further lead to enrichment of soil-Pb levels within the vicinity of the berm. Decontamination measure is therefore required to minimize extensive contamination of surrounding soils of the impact berm due to rainfall runoff events.展开更多
Ecological risk assessment of metals in soils is important to develop the critical loads of metals in soils. Phytotoxicity is one of the endpoints for ecological risk assessment of soils contaminated with metals. The ...Ecological risk assessment of metals in soils is important to develop the critical loads of metals in soils. Phytotoxicity is one of the endpoints for ecological risk assessment of soils contaminated with metals. The sensitivity of eight Chinese plant species（bok choy, mustard, tomato, green chilli, paddy rice, barley, spinach and celery） to copper（Cu） and nickel（Ni） toxicity in two Chinese soils was investigated to assess their potential use for ecological risk assessment in the region. The results showed that bok choy and mustard were the two most sensitive species to Cu and Ni toxicities. Assessment of metal accumulation by the plants demonstrated that bok choy shoot had the highest bioconcentration factor（BCF, the ratio of metal concentration in plant shoots to metal concentration in soil）. Given the importance of bok choy to agricultural production in Asia, it is therefore important that these sensitive plant species are included in species sensitivity distributions for ecological risk assessment of Cu and Ni in soils.展开更多
文摘Surface runoff from rainfall event is an important indicator of metal mobility in soil, which may enhance non-point source contamination of soil. This study is designed to assess the mobility of soil-bound lead through simulated rainfall runoff experiment and its spatial distribution within the vicinity of a berm at a major military shooting range. Contamination was more significant at the impact area of berm, indicating threefold increase in Pb (17,500 ± 3811 μg/g) within a space of ten years. However, the non-impact area (459 ± 147 μg/g) was less contaminated. Other metals (Cu, Cd, Cr, Ni and Zn) analyzed were about background levels except for Cu at impact area. The enrichment ratio of Pb in runoff sediments was mostly high for the 0.43 mm sediment fractions independent of rainfall condition. Principal component analysis (PCA) biplot showed strong correlation between spatial distributions of metals around the vicinity of the berm (farmlands behind the berm) with concentrations on the impact berm soil. Surface runoff simulated on impact area soil had high concentrations of Pb (40.4 - 65.6 μg/mL) which could further lead to enrichment of soil-Pb levels within the vicinity of the berm. Decontamination measure is therefore required to minimize extensive contamination of surrounding soils of the impact berm due to rainfall runoff events.
基金financial support by the National Natural Science Foundation of China(40971262,40620120436 and 41401361)the International Copper Association,Rio Tinto Pty Ltd.and the Nickel Producers Environmental Research Association
文摘Ecological risk assessment of metals in soils is important to develop the critical loads of metals in soils. Phytotoxicity is one of the endpoints for ecological risk assessment of soils contaminated with metals. The sensitivity of eight Chinese plant species（bok choy, mustard, tomato, green chilli, paddy rice, barley, spinach and celery） to copper（Cu） and nickel（Ni） toxicity in two Chinese soils was investigated to assess their potential use for ecological risk assessment in the region. The results showed that bok choy and mustard were the two most sensitive species to Cu and Ni toxicities. Assessment of metal accumulation by the plants demonstrated that bok choy shoot had the highest bioconcentration factor（BCF, the ratio of metal concentration in plant shoots to metal concentration in soil）. Given the importance of bok choy to agricultural production in Asia, it is therefore important that these sensitive plant species are included in species sensitivity distributions for ecological risk assessment of Cu and Ni in soils.
