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121.
有机酸土柱淋洗法修复重金属污染土壤 总被引:10,自引:1,他引:9
通过室内模拟实验,采用土柱淋洗方法,研究草酸、柠檬酸、乙酸和酒石酸溶液对某电镀厂附近土壤中重金属的去除效果。探讨了淋洗剂浓度、淋洗次数和淋洗时间等对淋洗效果的影响,研究草酸淋洗前后土壤中重金属形态的变化。结果表明,淋洗过程中铬的去除效果明显滞后于铜、锌和镍3种重金属离子。1 mol/L的草酸在土水比为1∶1,淋洗5h,淋洗4次的条件下可以达到最佳淋洗效果,Cu、Zn、Ni和Cr的去除率分别是99.6%、66.98%、88.7%和18.23%。 相似文献
122.
123.
The relations between natural and civic place attachment and pro-environmental behavior 总被引:2,自引:0,他引:2
The relation between place attachment and pro-environmental behavior is unclear. Studies have reported that place attachment is associated both with more and less pro-environmental behavior. To help clarify this, we distinguished two dimensions of place attachment: civic and natural, and explored their respective influences on pro-environmental behavior. A community sample of residents (N = 104) from two proximate towns with different environmental reputations reported the strength of their civic and natural place attachment, their performance of various pro-environmental behaviors, and a number of sociodemographic characteristics. Regression analyses revealed that natural, but not civic place attachment predicted pro-environmental behavior when controlling for the town, length of residence, gender, education and age. This demonstrates that research and theory on place attachment should consider its civic and natural dimensions independently. 相似文献
124.
Despite annual increases in the amount of material solid waste (MSW) that is recycled in the United States, the overall amount of MSW generated continues to increase. In an effort to identify and test specific predictors of curbside recycling behavior, the current study adapted the empirically validated Information–Motivation–Behavioral Skills model (IMB), traditionally used to predict personal health behavior, to explain curbside recycling behavior. Using structured computer assisted telephone surveys with two random community samples; structural equation models indicated that the IMB model significantly predicted curbside recycling. Data from the current study provides specific information about critical psychosocial determinants of curbside recycling behavior and public policy implications. 相似文献
125.
For conifer stands in NW-Germany with high DIN load (23-35 kg N ha−1 a−1) and a long history of nitrogen export the risk of N mobilization were investigated. Ammonium is the most mobilized N species, pointing towards either conditions not favoring nitrification or, more likely - under the dominant aerobic conditions - a very high amount of ammonium in the forest floor. Independence of net nitrification and net ammonification from each other indicates the existence of two separate systems. The nitrifying system depends very much on biotic conditions - as a function of energy and moisture - and seems not to be directly related to N deposition. In contrast, for the ammonification system (Oe horizon) a correlation with the sum of ammonium deposition three months prior to sampling was found. However, the role of disturbance, i.e. nitrogen export, during the last centuries and the role of recovery of the N balance during the last 150 years is still not clear. 相似文献
126.
Tanu Jindal Dileep K. Singh H. C. Agarwal 《Journal of environmental science and health. Part. B》2013,48(3):309-320
Abstract Dissipation, degradation and leaching of fresh 14C coumaphos, alkylated 14C coumaphos and aged residues of 14C coumaphos from vats were studied in alkaline sandy loam soil in soil columns in the field under subtropical conditions in Delhi for a year. Dissipation, degradation and bound residue formation was more in case of alkali treated coumaphos than fresh coumaphos. After 365 days total residues of fresh coumaphos accounted for 33.25% while that of alkali treated coumaphos was 19.12%. Bound residue formation was almost double in case of alkali treated coumaphos (18.95%) than fresh coumaphos (9.53%) after 150 days followed by release of bound residue in both the cases. The proportion of metabolites 4 ‐ methylumbelliferone, chlorferon and potasan collectively was 86.05% in fresh coumaphos extractable residues while the same was 91.74% in alkali treated coumaphos after 365 days. Aged residues from vats containing copper sulphate and buffer were found to be more persistent in soil as total residues remained were 95.58% in comparison with 83.09% total residues of aged residues from vats containing only buffer after 150 days of treatment. Copper sulphate seems to inhibit the degradatiion of coumaphos in soil by microorganisms. Chlorferon was the major metabolite in generally all the samples. Coumaphos did not leach below 10 cm in all the cases. 相似文献
127.
Abstract Male corn earworm moths, Helicoverpa zea (Boddie), were captured in conical Texas pheromone traps (cone traps) and bucket traps baited with four different commercial lures manufactured by three different manufacturers. Because significant numbers were captured in bucket traps baited with some of the lures, and none with others, the volatile emissions from all of the lures were sampled and analyzed by gas Chromatographic methods. The numbers of males captured in two types of trap were compared with bait emissions in an endeavor to define a more effective lure for bucket traps. The lure from one manufacturer captured the same numbers of males in both trap types; one captured more in bucket traps than in cone traps, and another captured only a small number in bucket traps. The emission rate of all active compounds from each of the different lures was approximately linear for the duration of the assays. A gas‐liquid Chromatographic peak associated with a third compound, (Z)‐9‐tetradecenal, which reduces behavioral responses, was observed in the emissions from all lures evaluated. The effectiveness of the Hercon (Emmigsville, PA) lure in capturing males in both types of trap was associated with a lower emission of (Z)‐l 1‐hexadecenal, (Z)‐9‐hexadecenal and (Z)‐9‐tetradecenal than from the other lures. 相似文献
128.
摘要以镁盐、铝盐、纯碱和烧碱为原料制备了一种多孔镁铝复合氧化物(P—Mg3.1AlO4.6),其比表面积、平均孔径和总孔容分别为206.3m2/g、8.961nm和0.4208cm3/g。研究了这种多孑L材料对水溶液中cr(VI)的吸附性能,在25~45qC时,静态吸附量为82.32~141.7mg/g;当初始浓度100mg/L、流速5mL/min、床层高度10cm和pH=6时,半穿透时间、半穿透吸附量和饱和吸附量分别为406rain、49.28ing/g和51.30Ing/g;拟合参数及误差分析表明,cr(Ⅵ)在P—M敬。AIO4.6上的静态吸附过程符合Freundlich等温方程式和伪二级动力学方程,Yoon·Nelson模型能很好地预测cr(Ⅵ)在P—Mg3.1A104.6上的动态穿透曲线。 相似文献
129.
Quantification of nitrate leaching from German forest ecosystems by use of a process oriented biogeochemical model 总被引:1,自引:0,他引:1
Kiese R Heinzeller C Werner C Wochele S Grote R Butterbach-Bahl K 《Environmental pollution (Barking, Essex : 1987)》2011,159(11):3204-3214
Simulations with the process oriented Forest-DNDC model showed reasonable to good agreement with observations of soil water contents of different soil layers, annual amounts of seepage water and approximated rates of nitrate leaching at 79 sites across Germany. Following site evaluation, Forest-DNDC was coupled to a GIS to assess nitrate leaching from German forest ecosystems for the year 2000. At national scale leaching rates varied in a range of 0–>80 kg NO3–N ha−1 yr−1 (mean 5.5 kg NO3–N ha−1 yr−1). A comparison of regional simulations with the results of a nitrate inventory study for Bavaria showed that measured and simulated percentages for different nitrate leaching classes (0–5 kg N ha−1 yr−1:66% vs. 74%, 5–15 kg N ha−1 yr−1:20% vs. 20%, >15 kg N ha−1 yr−1:14% vs. 6%) were in good agreement. Mean nitrate concentrations in seepage water ranged between 0 and 23 mg NO3–N l−1. 相似文献
130.
Kros J Frumau KF Hensen A de Vries W 《Environmental pollution (Barking, Essex : 1987)》2011,159(11):3171-3182
The integrated modelling system INITIATOR was applied to a landscape in the northern part of the Netherlands to assess current nitrogen fluxes to air and water and the impact of various agricultural measures on these fluxes, using spatially explicit input data on animal numbers, land use, agricultural management, meteorology and soil. Average model results on NH3 deposition and N concentrations in surface water appear to be comparable to observations, but the deviation can be large at local scale, despite the use of high resolution data. Evaluated measures include: air scrubbers reducing NH3 emissions from poultry and pig housing systems, low protein feeding, reduced fertilizer amounts and low-emission stables for cattle. Low protein feeding and restrictive fertilizer application had the largest effect on both N inputs and N losses, resulting in N deposition reductions on Natura 2000 sites of 10% and 12%, respectively. 相似文献