Rapid industrialization and economic development have left a great amount of industrial facilities,such as chemical,smelting and mining industries,throughout the country over the past few decades.As a result,a wide ra...Rapid industrialization and economic development have left a great amount of industrial facilities,such as chemical,smelting and mining industries,throughout the country over the past few decades.As a result,a wide range of toxic pollutants are generated and discharged directly or indirectly into the soil environment[1].展开更多
Phosphine is a part of an atmospheric link of phosphorus cycle on earth, which could be an important pathway for phosphorus transport in environment. Wetland ecosystems are important locations for global biogeochemica...Phosphine is a part of an atmospheric link of phosphorus cycle on earth, which could be an important pathway for phosphorus transport in environment. Wetland ecosystems are important locations for global biogeochemical phosphorus cycle. In this study, production and emission fluxes of free phosphine from four wetlands types in southern China were observed in different seasons. The results showed that the concentration of phosphine liberated from wetlands was at pg/m^3·ng/m^3 level. The emission concentrations of different wetlands followed the sequence： paddy field （51.83 ± 3.06） ng/m^3 〉/marsh （46.54 ± 20.55） ng/m^3 〉 lake （37.05 ± 22.74） ng/m^3 〉〉 coastal wetland （1.71 ± 0.73） ng/m^3, the positive phosphine emission flux occurred in rice paddy field （6.67 ± 5.18） ng/（m^2.hr） and marsh （6.23 ± 26.9） ng/（m^2.hr）, while a negative phosphine flux of （-13.11 ± 35.04） ng/（m^2.hr） was observed on the water-air interface of Lake Taihu, suggesting that paddy field and marsh may be important sources for phosphine gas in atmosphere, while lake may be a sink of atmospheric phosphine gas during the sampling period. Atmospheric phosphine levels and emission flux from Yancheng marsh and rice paddy field varied in different seasons and vegetational zones. Both diffusion resistance in aqueous phase and temperature were dominating factors for the production and transportation of phosphine to atmosphere.展开更多
A terrestrial biotic ligand model（t-BLM） was developed to predict nickel toxicity to wheat（Triticum aestivum） root elongation in hydroponic solutions. The competitive effects of five major cations（Ca^（2＋）, Mg^...A terrestrial biotic ligand model（t-BLM） was developed to predict nickel toxicity to wheat（Triticum aestivum） root elongation in hydroponic solutions. The competitive effects of five major cations（Ca^（2＋）, Mg^（2＋）, Na~＋, K~＋and H~＋） on Ni toxicity were investigated and Mg^（2＋）was found to be a strong competitor, while H＋showed less competing effect. Besides free Ni^（2＋）,the toxicity induced by the species NiHCO_3~＋ was non-neglect able at pH 〉 7 because NiHCO_3~＋ occupied a significant fraction of total Ni under such condition. Thus, a t-BLM including Ni^（2＋）, NiHCO_3~＋, Mg^（2＋）, and H＋could successfully predict the nickel toxicity to wheat root elongation and it performed better prediction than the conventional free ion activity model.In addition, the model was examined with two sets of independent experiments, which contained multiple cations and low-molecular-weight organic acids to mimic the rhizosphere condition. The developed t-BLM well predicted nickel toxicity in both experiments since it can account in both complexation and competition effects, suggesting its potential to be used in a complicated matrix like soil solution. This study provides direct evidence that the t-BLM is a reliable method for the risk assessment of nickel in terrestrial system.展开更多
基金supported by the National Key Research and Development Program of China(2018YFC1800600)the National Natural Science Foundation of China(42022057 and U1906225)。
文摘Rapid industrialization and economic development have left a great amount of industrial facilities,such as chemical,smelting and mining industries,throughout the country over the past few decades.As a result,a wide range of toxic pollutants are generated and discharged directly or indirectly into the soil environment[1].
基金supported by the National Basic Research Program (973) of China (No. 2008CB418003)the Jiangsu Natural Science Foundation (No. BK2008276)+2 种基金the National Natural Science Foundation of China (No.21077051, 30700020)the International Foundation of Science (No. A/4425-1)the Self-Research Subject of State Key Laboratory of Pollution Control and Resource Reuse
文摘Phosphine is a part of an atmospheric link of phosphorus cycle on earth, which could be an important pathway for phosphorus transport in environment. Wetland ecosystems are important locations for global biogeochemical phosphorus cycle. In this study, production and emission fluxes of free phosphine from four wetlands types in southern China were observed in different seasons. The results showed that the concentration of phosphine liberated from wetlands was at pg/m^3·ng/m^3 level. The emission concentrations of different wetlands followed the sequence： paddy field （51.83 ± 3.06） ng/m^3 〉/marsh （46.54 ± 20.55） ng/m^3 〉 lake （37.05 ± 22.74） ng/m^3 〉〉 coastal wetland （1.71 ± 0.73） ng/m^3, the positive phosphine emission flux occurred in rice paddy field （6.67 ± 5.18） ng/（m^2.hr） and marsh （6.23 ± 26.9） ng/（m^2.hr）, while a negative phosphine flux of （-13.11 ± 35.04） ng/（m^2.hr） was observed on the water-air interface of Lake Taihu, suggesting that paddy field and marsh may be important sources for phosphine gas in atmosphere, while lake may be a sink of atmospheric phosphine gas during the sampling period. Atmospheric phosphine levels and emission flux from Yancheng marsh and rice paddy field varied in different seasons and vegetational zones. Both diffusion resistance in aqueous phase and temperature were dominating factors for the production and transportation of phosphine to atmosphere.
基金the Natural Science Foundation of China(Nos.21577062 and 21277068)the Key Research and Development Program of Jiangsu Province(No.BE2015708)for financial support
文摘A terrestrial biotic ligand model（t-BLM） was developed to predict nickel toxicity to wheat（Triticum aestivum） root elongation in hydroponic solutions. The competitive effects of five major cations（Ca^（2＋）, Mg^（2＋）, Na~＋, K~＋and H~＋） on Ni toxicity were investigated and Mg^（2＋）was found to be a strong competitor, while H＋showed less competing effect. Besides free Ni^（2＋）,the toxicity induced by the species NiHCO_3~＋ was non-neglect able at pH 〉 7 because NiHCO_3~＋ occupied a significant fraction of total Ni under such condition. Thus, a t-BLM including Ni^（2＋）, NiHCO_3~＋, Mg^（2＋）, and H＋could successfully predict the nickel toxicity to wheat root elongation and it performed better prediction than the conventional free ion activity model.In addition, the model was examined with two sets of independent experiments, which contained multiple cations and low-molecular-weight organic acids to mimic the rhizosphere condition. The developed t-BLM well predicted nickel toxicity in both experiments since it can account in both complexation and competition effects, suggesting its potential to be used in a complicated matrix like soil solution. This study provides direct evidence that the t-BLM is a reliable method for the risk assessment of nickel in terrestrial system.
