尽管通过流量的氮(N) 损失并且从农田沥滤被怀疑贡献包围水系统的恶化，没有最后的证据让水稻土证明这个假设。在这研究，地小区试验被进行通过流量调查 N 损失并且在大米(Oryza sativa L.) 与 3 N 受精率沥滤二连续的年小麦(Triticum a...尽管通过流量的氮(N) 损失并且从农田沥滤被怀疑贡献包围水系统的恶化，没有最后的证据让水稻土证明这个假设。在这研究，地小区试验被进行通过流量调查 N 损失并且在大米(Oryza sativa L.) 与 3 N 受精率沥滤二连续的年小麦(Triticum aestivum L.) 在泰胡·莱克区域的旋转，中国。一个水收集系统被设计收集流量并且沥滤为米饭和小麦季节的 ates。结果出现了那溶解 N (DN ) ，而非微粒 N (PN ) ，是由流量的 N 损失的主要表格。NO3 ? 在流量的 -N 集中在 0.1 和 43.7 mg L 之间 ? ，而 NH4+-N 集中从在察觉限制下面到 8.5 mg L ? 。由流量的全部的 N (TN ) 负担是 1.0 17.9 和 5.2 38.6 kg 哈？在米饭和小麦季节期间，分别地并且主要损失在庄稼的早成长的阶段发生了。氮集中在沥滤 ates 在米饭季节期间在 1.0 mg L 下面？并且独立于 N 申请率，而那些在小麦季节期间增加了到 8.2 mg L？并且被化肥率影响。通过流量的 TN 的年度损失并且沥滤从大米小麦的 13.7 48.1 kg ha-1 正在收割系统，财务为 5.6%8.3% 总数使用了 N。它被结束在 N 受精率的那减小，特别当庄稼在生物资源是小的时，能为水系统降低 N 污染潜力。展开更多
Increasing attention has been paid to air pollution control (APC) resi dues in China recently due to the rising proportion of waste incineration and th e hazardous characteristics of the residues, among which heavy me...Increasing attention has been paid to air pollution control (APC) resi dues in China recently due to the rising proportion of waste incineration and th e hazardous characteristics of the residues, among which heavy metal leaching to xicity plays an important role. Leaching behavior and potential risk of Pb and Z n in the APC residues from a Shanghai municipal solid waste (MSW) incinerator wa s studied, based on the leaching tests under different conditions and theoretica l calculation using a geochemical thermodynamic equilibrium model MINTEQA2. Res ults showed that, extractant species and liquid to solid (L/S) ratio predomina ntly controlled the leaching toxicity of Pb and Zn, while ionic strength, vibr ation method and leaching time had less effect on the metals release. Leachate/f inal pH determined the metal leaching behavior, which changed the speciation of heavy metals in the extraction system. The equilibrium aqueous speciation, preci pitation-dissolution of Pb and Zn was investigated according to the model comput ation, which was well in agreement with the experimental results.展开更多
A glasshouse experiment using a rhizobox technique was conducted to examine salt dynamics in the rhizosphere of a salt-tolerant grass, Puccinellia ciliata Bor. ’Irwin Hunter’, grown in a loamy soil, and to study the...A glasshouse experiment using a rhizobox technique was conducted to examine salt dynamics in the rhizosphere of a salt-tolerant grass, Puccinellia ciliata Bor. ’Irwin Hunter’, grown in a loamy soil, and to study the effect of rainfall flush on salt accumulation in the rhizosphere. The rhizobox (10 × 5.5 × 50 cm) had a nylon mesh (1 μm) positioned vertically in the middle to create two compartments filled with soil amended with 1 g NaCl kg-1. The plants were grown in one compartment only. Flushed treatments received 275 mL of deionized water two days before harvest. In the plant-growing compartment, soils were sectioned vertically at 5 cm intervals. Significant differences in soil electrical conductivity (EC) (P < 0.05) and pH (P < 0.05) were observed for depths, but not between flushed and non-flushed treatments. In the no-plant compartment (rhizosphere), soil cores were taken horizontally at depths of 5, 20 and 40 cm and sliced at 1, 2, 3, 4, 5, 7, 10, 15 and 20 mm away from the roots. Soil EC and Cl- concentration at the 5 and 20 cm depths, and Na+ concentration at the 5 cm depth significantly decreased (P < 0.05) with the distance away from the root, but no significant differences were observed in soil pH and concentrations of the K+ and Ca2+. The flush treatment only had significant influence on soil EC, pH, and Cl- concentration at the 20 cm depth. Thus, salt accumulation could occur in the rhizosphere of salt-tolerant species on saline soils, and the periodic low rainfall might not have a strong influence on salt distribution in the rhizosphere and/or root zone.展开更多
基金the National Natural Science Foundation of China (Nos.40571077 and 30390080)and the Knowledge Innovation Project of the Chinese Academy of Sciences (No.KZCX2-413).
文摘尽管通过流量的氮(N) 损失并且从农田沥滤被怀疑贡献包围水系统的恶化，没有最后的证据让水稻土证明这个假设。在这研究，地小区试验被进行通过流量调查 N 损失并且在大米(Oryza sativa L.) 与 3 N 受精率沥滤二连续的年小麦(Triticum aestivum L.) 在泰胡·莱克区域的旋转，中国。一个水收集系统被设计收集流量并且沥滤为米饭和小麦季节的 ates。结果出现了那溶解 N (DN ) ，而非微粒 N (PN ) ，是由流量的 N 损失的主要表格。NO3 ? 在流量的 -N 集中在 0.1 和 43.7 mg L 之间 ? ，而 NH4+-N 集中从在察觉限制下面到 8.5 mg L ? 。由流量的全部的 N (TN ) 负担是 1.0 17.9 和 5.2 38.6 kg 哈？在米饭和小麦季节期间，分别地并且主要损失在庄稼的早成长的阶段发生了。氮集中在沥滤 ates 在米饭季节期间在 1.0 mg L 下面？并且独立于 N 申请率，而那些在小麦季节期间增加了到 8.2 mg L？并且被化肥率影响。通过流量的 TN 的年度损失并且沥滤从大米小麦的 13.7 48.1 kg ha-1 正在收割系统，财务为 5.6%8.3% 总数使用了 N。它被结束在 N 受精率的那减小，特别当庄稼在生物资源是小的时，能为水系统降低 N 污染潜力。
基金The Key Project of Shanghai Council of Science and Technology(No. 032312043)
文摘Increasing attention has been paid to air pollution control (APC) resi dues in China recently due to the rising proportion of waste incineration and th e hazardous characteristics of the residues, among which heavy metal leaching to xicity plays an important role. Leaching behavior and potential risk of Pb and Z n in the APC residues from a Shanghai municipal solid waste (MSW) incinerator wa s studied, based on the leaching tests under different conditions and theoretica l calculation using a geochemical thermodynamic equilibrium model MINTEQA2. Res ults showed that, extractant species and liquid to solid (L/S) ratio predomina ntly controlled the leaching toxicity of Pb and Zn, while ionic strength, vibr ation method and leaching time had less effect on the metals release. Leachate/f inal pH determined the metal leaching behavior, which changed the speciation of heavy metals in the extraction system. The equilibrium aqueous speciation, preci pitation-dissolution of Pb and Zn was investigated according to the model comput ation, which was well in agreement with the experimental results.
文摘A glasshouse experiment using a rhizobox technique was conducted to examine salt dynamics in the rhizosphere of a salt-tolerant grass, Puccinellia ciliata Bor. ’Irwin Hunter’, grown in a loamy soil, and to study the effect of rainfall flush on salt accumulation in the rhizosphere. The rhizobox (10 × 5.5 × 50 cm) had a nylon mesh (1 μm) positioned vertically in the middle to create two compartments filled with soil amended with 1 g NaCl kg-1. The plants were grown in one compartment only. Flushed treatments received 275 mL of deionized water two days before harvest. In the plant-growing compartment, soils were sectioned vertically at 5 cm intervals. Significant differences in soil electrical conductivity (EC) (P < 0.05) and pH (P < 0.05) were observed for depths, but not between flushed and non-flushed treatments. In the no-plant compartment (rhizosphere), soil cores were taken horizontally at depths of 5, 20 and 40 cm and sliced at 1, 2, 3, 4, 5, 7, 10, 15 and 20 mm away from the roots. Soil EC and Cl- concentration at the 5 and 20 cm depths, and Na+ concentration at the 5 cm depth significantly decreased (P < 0.05) with the distance away from the root, but no significant differences were observed in soil pH and concentrations of the K+ and Ca2+. The flush treatment only had significant influence on soil EC, pH, and Cl- concentration at the 20 cm depth. Thus, salt accumulation could occur in the rhizosphere of salt-tolerant species on saline soils, and the periodic low rainfall might not have a strong influence on salt distribution in the rhizosphere and/or root zone.
