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371.
环境生态风险评估(ERA)流程已经被纳入全球环境政策中,既用于规范新化学物质的授权和营销(前瞻性环境生态风险评估),也用于评估潜在的污染场地(回顾性环境生态风险评估)。将土壤生态毒理学应用于风险评估,能阐明有毒物质对土壤生态系统中生命有机体的危害程度与范围。笔者主要介绍了应用评估因子法和物种敏感度分布法对基于效应数据进行的外推与估算,并综述了欧美等主要国家和地区的土壤生态风险评估框架、相关法律法规及其实施情况等,为中国开展土壤污染物生态毒理效应和风险评估等相关研究提供参考。 相似文献
372.
通过对浙江省近700组实际土壤样品进行分析,研究了土壤中铜、铅、锌、铬、镍、镉、砷、汞7种重金属和砷测定的精密度控制指标(实验室内相对偏差和实验室间相对偏差),并与行业标准分析方法和文献进行了比较,旨在为环境监测质量控制与质量保证工作提供参考。经统计分析,建议实验室内相对偏差控制指标如下:铜,≤15%;铅,≤15%;锌,≤15%;铬,≤15%;镍,≤15%;镉,≤20%;砷,≤15%;汞,≤50%。建议实验室间相对偏差控制指标如下:铜,≤25%;铅,≤25%;锌,≤20%;铬,≤20%;镍,≤25%;镉,≤35%;砷,≤25%;汞,≤55%。 相似文献
373.
通过湿法消解土壤样品,利用石墨炉原子吸收分光光度法(GAAS)和火焰原子吸收分光光度法(FAAS)测定不同土壤样品中铅的含量,以验证2种方法的有效性并加以对比。实验结果表明:2种方法均满足土壤中铅含量的测定要求,测定的标准土样含量均在标准值的不确定度范围内,GAAS方法测定结果更接近保证值。二者的相对标准偏差(RSD)值均低于1.5%,FAAS方法的精密度更高,且具有快速简单等优势。 相似文献
374.
375.
Kumar PR 《Environmental monitoring and assessment》2006,117(1-3):215-233
In this paper, an attempt has been made to highlight an experimental methodology for monitoring contaminant transport through
locally available silty soil and commercially available clay in geotechnical centrifuge models, for different compaction states.
Use of multiple depth sensors to determine depth distribution of sodium chloride in the soil column has been detailed. The
obtained results have been compared with argentometric method. To validate the centrifuge modelling, modelling of models has
been used. The test setup developed can simulate contaminant transport mechanisms through the soil mass, which is approximately
10 m deep, over a period of 600 days. R
e and P
e are found to be N times higher in the centrifuge models. These numbers are found to be several orders less than unity. This indicates that
laminar flow prevails and the dominating Cl− transport mechanism in centrifuge is diffusion. The study also highlights the fact that the geotechnical centrifuge modelling
can be used as a viable alternative to field scale experimentation. 相似文献
376.
Using Ion-Exchange Resins to Study Soil Response to Experimental Watershed Acidification 总被引:1,自引:0,他引:1
Szillery JE Fernandez IJ Norton SA Rustad LE White AS 《Environmental monitoring and assessment》2006,116(1-3):383-398
Ion-exchange resins (IER) offer alternative approaches to measuring ionic movement in soils that may have advantages over
traditional approaches in some settings, but more information is needed to understand how IER compare with traditional methods
of measurement in forested ecosystems. At the Bear Brook Watershed in Maine (BBWM), one of two paired, forested watersheds
is treated bi-monthly with S and N (28.8 and 25.2kgha−1yr−1 of S and N, respectively). Both IER and ceramic cup tension lysimeters were used to study soil solution responses after ∼11
years of treatment. Results from both methods showed treatments resulted in the mobilization of base cations and Al, and higher
SO4—S and inorganic N in the treated watershed. Both methods indicated similar differences in results associated with forest
type (hardwoods versus softwoods), a result of differences in litter quality and atmospheric aerosol interception capacity.
The correlation between lysimeter and IER data for individual analytes varied greatly. Significant correlations were evident
for Na (r=0.75), Al (r=0.65), Mn (r=0.61), Fe (r=0.57), Ca (r=0.49), K (r=0.41) and NO3—N (r=0.59). No correlation was evident between IER and soil solution data for NH4—N and Pb. Both IER and soil solution techniques suggested similar interpretations of biogeochemical behavior in the watershed. 相似文献
377.
Jaradat QM Massadeh AM Zaitoun MA Maitah BM 《Environmental monitoring and assessment》2006,112(1-3):197-210
Chemical and physical size fractionation of heavy metals were carried out on 20 soil samples from the scrap yard area. Tessier
method was used in sequential extraction. Cadmium showed the highest levels among the other elements studied in the exchangeable
fraction (about 33%), while other elements showed low levels in this fraction (≥1%). Lead and manganese were mostly found
in the Fe–Mn oxide fraction, zinc and iron were mostly in residual fraction, while copper was mostly found in the organic
fraction of the soil. Soil samples were size-fractionated into four sizes: 1000–500, 500–125, 125–53, and less than 53 μm.
The highest levels of Fe, Cu, Pb, Mn, and Cd were found in the medium fraction (500–125 μm), while zinc showed its highest
levels in the fine fraction (125–53 μm). The order of heavy metal load in the size fractions was found to be medium > fine
> coarse > silt for Fe, Mn, Cu, Pb, and Cd, where it was found as fine > medium > coarse > silt for zinc. 相似文献
378.
379.
城市湿地是城市生态系统的重要组成部分,在土壤抗侵蚀方面起重要作用.以哈尔滨松北区城市湿地为研究对象,在哈尔滨松北区湿地的西区、中区及东区沿线共布设采样点3个.哈尔滨松北区城市湿地土壤抗侵蚀效益价值通过湿地减少土地废弃、河道淤积和土壤中肥力流失三方面的价值来估算.结果表明:哈尔滨市松北区城市湿地保护土壤、减少土壤侵蚀的总效益价值为1.900×107元/a;湿地土壤在抗侵蚀效益中的贡献率占总效益的1/5,其效益价值为3.800×106元/a. 相似文献
380.