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11.
Pedogenesis, geochemical forms of heavy metals, and artifact weathering in an urban soil chronosequence, Detroit, Michigan 总被引:1,自引:0,他引:1
An urban soil chronosequence in downtown Detroit, MI was studied to determine the effects of time on pedogenesis and heavy metal sequestration. The soils developed in fill derived from mixed sandy and clayey diamicton parent materials on a level late Pleistocene lakebed plain under grass vegetation in a humid-temperate (mesic) climate. The chronosequence is comprised of soils in vacant lots (12 and 44 years old) and parks (96 and 120 years old), all located within 100 m of a roadway. An A-horizon 16 cm thick with 2% organic matter has developed after only 12 years of pedogenesis. The 12 year-old soil shows accelerated weathering of iron (e.g. nails) and cement artifacts attributed to corrosion by excess soluble salts of uncertain origin. Carbonate and Fe-oxide are immobilizing agents for heavy metals, hence it is recommended that drywall, plaster, cement and iron artifacts be left in soils at brownfield sites for their ameliorating effects. 相似文献
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Gallagher FJ Pechmann I Holzapfel C Grabosky J 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1159-1166
Recognizing the growing importance of both structure (maintenance of biodiversity) and function (fostering natural cycles) of urban ecologies, we examine coarse scale (herbaceous, shrub and forest) beta guild trajectory in an urban brownfield. The distribution of the pioneer forest assemblage dominated by Betula populifolia Marsh. and Populus spp. could be correlated positively with total soil metal load (arsenic, cadmium, chromium, copper, lead, zinc, lead and vanadium),whereas herbaceous and shrub guilds were negatively correlated. Distinct assemblage development trajectories above and below a critical soil metal threshold are demonstrated. In addition, we postulate that the translocation of metals into the plant tissue of several dominant species may provide a positive feedback loop, maintaining relatively high concentrations of metals in the litter and soil. Therefore assembly theory, which allows for the development of alternate stable states, may provide a better model for the establishment of restoration objectives on degraded urban sites. 相似文献
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Arsenic stability and mobilization in soil at an amenity grassland overlying chemical waste (St. Helens, UK) 总被引:1,自引:0,他引:1
William Hartley Nicholas M. Dickinson Christopher French Trevor G. Piearce Nicholas W. Lepp 《Environmental pollution (Barking, Essex : 1987)》2009,157(3):847-856
A 6.6 ha grassland, established on a former chemical waste site adjacent to a residential area, contains arsenic (As) in surface soil at concentrations 200 times higher than UK Soil Guideline Values. The site is not recognized as statutory contaminated land, partly on the assumption that mobility of the metalloid presents a negligible threat to human health, groundwater and ecological receptors. Evidence for this is evaluated, based on studies of the effect of organic (green waste compost) and inorganic (iron oxides, lime and phosphate) amendments on As fractionation, mobility, plant uptake and earthworm communities. Arsenic mobility in soil was low but significantly related to dissolved organic matter and phosphate, with immobilization associated with iron oxides. Plant uptake was low and there was little apparent impact on earthworms. The existing vegetation cover reduces re-entrainment of dust-blown particulates and pathways of As exposure via this route. Minimizing risks to receptors requires avoidance of soil exposure, and no compost or phosphate application. 相似文献
14.
Gallagher FJ Pechmann I Bogden JD Grabosky J Weis P 《Environmental pollution (Barking, Essex : 1987)》2008,153(2):351-361
Anthropogenic sources of toxic elements have had serious ecological and human health impacts. Analysis of the soil samples from a brownfield within Liberty State Park, Jersey City, NJ, USA, showed that arsenic, chromium, lead, zinc and vanadium exist at concentrations above those considered ambient for the area. Accumulation and translocation features were characterized for the dominant plant species of four vegetative assemblages. The trees Betula populifolia and Populus deltoides were found to be accumulating Zn in leaf tissue at extremely high levels. B. populifolia, P. deltoides and Rhus copallinum accumulated Cr primarily in the root tissue. A comparison of soil metal maps and vegetative assemblage maps indicates that areas of increasing total soil metal load were dominated by successional northern hardwoods while semi-emergent marshes consisting mostly of endemic species were restricted primarily to areas of low soil metal load. 相似文献
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Huan Feng Yu Qian Frank J. Gallagher Weiguo Zhang Lizhong Yu Changjun Liu Keith W. Jones Ryan Tappero 《环境科学学报(英文版)》2016,28(3):172-182
Liberty State Park in New Jersey,USA,is a "brownfield" site containing various levels of contaminants.To investigate metal uptake and distributions in plants on the brownfield site,Phragmites australis and Typha latifolia were collected in Liberty State Park during the growing season(May–September)in 2011 at two sites with the high and low metal loads,respectively.The objective of this study was to understand the metal(Fe,Mn,Cu,Pb and Zn)concentration and spatial distributions in P.australis and T.latifolia root systems with micro-meter scale resolution using synchrotron X-ray microfluorescence(μXRF)and synchrotron X-ray computed microtomography(μCMT)techniques.The root structure measurement by synchrotron μCMT showed that high X-ray attenuation substance appeared in the epidermis.Synchrotron μXRF measurement showed that metal concentrations and distributions in the root cross-section between epidermis and vascular tissue were statistically different.Significant correlations were found between metals(Cu,Mn,Pb and Zn)and Fe in the epidermis,implying that metals were scavenged by Fe oxides.The results from this study suggest that the expression of metal transport and accumulation within the root systems may be element specific.The information derived from this study can improve our current knowledge of the wetland plant ecological function in brownfield remediation. 相似文献
17.
Arsenic mobility and speciation in a contaminated urban soil are affected by different methods of green waste compost application 总被引:3,自引:0,他引:3
William Hartley Nicholas M. Dickinson Elizabeth Leese Nicholas W. Lepp 《Environmental pollution (Barking, Essex : 1987)》2010,158(12):3560-3570
Application of green waste compost (GWC) to brownfield land is now common practice in soil restoration. However, previous studies have demonstrated both beneficial and detrimental effects on arsenic and metal mobility. In this paper, trace element behaviour was investigated following GWC application, either as surface mulch to, or mixed into soil from a previously described brownfield site in the U.K. Significant differences in arsenic mobility were observed between treatments. Mulching caused most disturbance, significantly increasing soil pore water As, together with Fe, P, Cr, Ni and dissolved organic carbon, the latter was a critical factor enhancing As mobilization. Arsenate was the main inorganic As species in soil pore water, increasing in concentration over time. An initial flush of potentially more toxic arsenite decreased 4 weeks after compost application. Biological processes appeared to play an important role in influencing As mobility. The results point to the necessity for careful management of As-contaminated soils. 相似文献
18.
Brownfields are abandoned, idled, or underused sites whose reuse necessitates some sort of intervention. These sites are largely
urban and are frequently contaminated. Brownfield management options can be associated with three types of environmental consequences:
those resulting from changes in the site’s environmental quality (primary impacts); those resulting from the actual intervention
stage (secondary impacts); and, if the vocation of the site changes, those resulting from effects on regional land use (tertiary
impacts). Different stakeholders and decision-making contexts will place a different importance on each of these types of
impacts. This article proposes a framework for comparing brownfield management options in regard to these three types of environmental
impacts and for interpreting these results from different perspectives. The assessment framework is based on consequential
life cycle assessment (LCA), which is shown to provide environmental information on the three types of impacts. The results
for a case study are presented, where a “rehabilitation” option allowing residential redevelopment is compared to an “exposure
minimization” option not resulting in the site being reused. Calculated primary and tertiary impacts are favorable to the
rehabilitation option, whereas secondary impacts are favorable to the exposure minimization option. A ternary diagram presents
the favorable option for different stereotypical perspectives. Tertiary impacts are much greater than secondary impacts, and
consequently all perspectives that consider tertiary impacts favor rehabilitation. The perspective that considers primary
and secondary impacts receives conflicting information. The ternary diagram, showing results for all perspectives, could possibly
be useful for consensus-building among stakeholders. 相似文献
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