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491.
Elizabeth Guthrie Nichols Rachel L. Cook James E. Landmeyer Brad Atkinson Donald R. Malone George Shaw Leilani Woods 《补救:环境净化治理成本、技术与工艺杂志》2014,24(2):29-46
A former bulk fuel terminal in North Carolina is a groundwater phytoremediation demonstration site where 3,250 hybrid poplars, willows, and pine trees were planted from 2006 to 2008 over approximately 579,000 L of residual gasoline, diesel, and jet fuel. Since 2011, the groundwater altitude is lower in the area with trees than outside the planted area. Soil‐gas analyses showed a 95 percent mass loss for total petroleum hydrocarbons (TPH) and a 99 percent mass loss for benzene, toluene, ethylbenzene, and xylenes (BTEX). BTEX and methyl tert‐butyl ether concentrations have decreased in groundwater. Interpolations of free‐phase, fuel product gauging data show reduced thicknesses across the site and pooling of fuel product where poplar biomass is greatest. Isolated clusters of tree mortalities have persisted in areas with high TPH and BTEX mass. Toxicity assays showed impaired water use for willows and poplars exposed to the site's fuel product, but Populus survival was higher than the willows or pines on‐site, even in a noncontaminated control area. All four Populus clones survived well at the site. © 2014 Wiley Periodicals, Inc.* 相似文献
492.
Nazli Yesiller James L. Hanson Jason T. Cox Danielle E. Noce 《Waste management (New York, N.Y.)》2014,34(5):848-858
This investigation was conducted to evaluate experimental determination of specific gravity (Gs) of municipal solid waste (MSW). Water pycnometry, typically used for testing soils was adapted for testing MSW using a large flask with 2000 mL capacity and specimens with 100–350 g masses. Tests were conducted on manufactured waste samples prepared using US waste constituent components; fresh wastes obtained prior and subsequent to compaction at an MSW landfill; and wastes obtained from various depths at the same landfill. Factors that influence specific gravity were investigated including waste particle size, compaction, and combined decomposition and stress history. The measured average specific gravities were 1.377 and 1.530 for as-prepared/uncompacted and compacted manufactured wastes, respectively; 1.072 and 1.258 for uncompacted and compacted fresh wastes, respectively; and 2.201 for old wastes. The average organic content and degree of decomposition were 77.2% and 0%, respectively for fresh wastes and 22.8% and 88.3%, respectively for old wastes. The Gs increased with decreasing particle size, compaction, and increasing waste age. For fresh wastes, reductions in particle size and compaction caused occluded intraparticle pores to be exposed and waste particles to be deformed resulting in increases in specific gravity. For old wastes, the high Gs resulted from loss of biodegradable components that have low Gs as well as potential access to previously occluded pores and deformation of particles due to both degradation processes and applied mechanical stresses. The Gs was correlated to the degree of decomposition with a linear relationship. Unlike soils, the Gs for MSW was not unique, but varied in a landfill environment due both to physical/mechanical processes and biochemical processes. Specific gravity testing is recommended to be conducted not only using representative waste composition, but also using representative compaction, stress, and degradation states. 相似文献
493.
R.P. Beaven K. Knox J.R. Gronow O. Hjelmar D. Greedy H. Scharff 《Waste management (New York, N.Y.)》2014,34(7):1191-1198
The key aspects of landfill operation that remain unresolved are the extended timescale and uncertain funding of the post-closure period. This paper reviews the topic and proposes an economic instrument to resolve the unsustainable nature of the current situation. Unsustainability arises from the sluggish degradation of organic material and also the slow flushing of potential pollutants that is exacerbated by low-permeability capping. A landfill tax or aftercare provision rebate is proposed as an economic instrument to encourage operators to actively advance the stabilization of landfilled waste. The rebate could be accommodated within existing regulatory and tax regimes and would be paid for: (i) every tonne of nitrogen (or other agreed leachate marker) whose removal is advanced via the accelerated production and extraction of leachate; (ii) every tonne of non-commercially viable carbon removed via landfill gas collection and treatment. The rebates would be set at a level that would make it financially attractive to operators and would encourage measures such as leachate recirculation, in situ aeration, and enhanced flushing. Illustrative calculations suggest that a maximum rebate of up to ~€50/tonne MSW would provide an adequate incentive. 相似文献
494.
495.
C. Henry Obasi U. Martin Obidiegwu N. Godwin Onyeagoro O. Innocent Arukalam C. Genevive Onuegbu N. Francis Onuoha M. Chinomso Ewulonu 《Journal of Polymers and the Environment》2017,25(3):544-555
We report in this paper the transport of an aromatic solvent, xylene through palm pressed fibre filled low density polyethylene composites studied at three different temperatures (40, 60, and 80 °C) by conventional weight-gain method. The diffusion parameters were investigated with special reference to the effect of fibre content, temperature and particle size. The effect of alkali treatment on solvent uptake was also analyzed. The transport coefficients of diffusion, permeation and sorption were determined to evaluate the influence of interface bonding on transport properties. The van’t Hoff relationship was used to determine the thermodynamic parameters and was found that the estimated free energies of sorption were all positive, indicating non-spontaneity of the solubility of PPF/LDPE composites. The first order kinetic rate constant and swelling parameters were also evaluated. 相似文献
496.
Owamah I. H. Izinyon O. C. Igbinewekan P. 《Journal of Material Cycles and Waste Management》2017,19(1):366-373
Journal of Material Cycles and Waste Management - In this study, the composition, characteristics and generation rates of solid waste (SW) in Ogbe-Ijoh community were investigated to provide... 相似文献
497.
Jaji MO Bamgbose O Odukoya OO Arowolo TA 《Environmental monitoring and assessment》2007,133(1-3):473-482
The quality of Ogun river in South-West, Nigeria was studied by a field survey for a period of 1 year (covering dry season
and rainy season). Water samples were collected from thirteen sites and analysed for physico-chemical and bacteriological
parameters as well as heavy metals using standard methods. Generally, the values obtained for turbidity, phosphate, oil and
grease, iron and faecal coliform from all the sites in both seasons were above the maximum acceptable limit set by the World
Health Organization (WHO) for drinking water. Also, the manganese content from all the sites in the dry season, lead concentrations
from three sites in the dry season and cadmium concentrations from some sites in both seasons were above the WHO limit. The
values obtained for total dissolved solids, dissolved oxygen and chloride at site M in the dry season and nitrate at site
J in the rainy season were also above the WHO limit. Pollution of Ogun river water along its course is evidenced by the high
concentrations of pollution indicators, nutrients and trace metals above the acceptable limit. This poses a health risk to
several rural communities who rely on the river primarily as their source of domestic water. The study showed a need for continuous
pollution monitoring programme of surface waters in Nigeria. 相似文献
498.
The Distribution and Sources of Polycyclic Aromatic Hydrocarbons in Surface Sediments Along the Egyptian Mediterranean Coast 总被引:2,自引:0,他引:2
El Nemr A Said TO Khaled A El-Sikaily A Abd-Allah AM 《Environmental monitoring and assessment》2007,124(1-3):343-359
Coastal marine sediment samples were collected from 31 sampling stations along the Egyptian Mediterranean Sea coast. All sediment
samples were analyzed to determine aliphatic and polycyclic aromatic hydrocarbons (PAHs) as well as total organic carbon (TOC)
contents and grain size analysis. Total concentrations of 16 EPA-PAHs in the sediments were varied from 88 to 6338 ng g−1 with an average value of 154 ng g−1 (dry weight). However, the concentrations of total aliphatic were varied from 1.3 to 69.9 ng g−1 with an average value of 15.6 ng g−1 (dry weight). The highest contents of PAHs were found in the Eastern harbor (6338 ng g−1), Manzala (5206 ng g−1) and El-Jamil East (4895 ng g−1) locations. Good correlations observed between a certain numbers of PAH concentrations allowed to identify its origin. The
average total organic carbon (TOC) percent was varied from 0.91 to 4.54%. Higher concentration of total pyrolytic hydrocarbons
(∑COMB) than total fossil hydrocarbons (∑PHE) declared that atmospheric fall-out is the significant source of PAHs to marine
sediments of the Egyptian Mediterranean coast. The selected marked compounds, a principal component analysis (PCA) and special
PAHs compound ratios (phenanthrene/anthracene vs fluoranthene/pyrene; ∑COMB/∑EPA-PAHs) suggest the pyrogenic origins, especially
traffic exhausts, are the dominant sources of PAHs in most locations. Interferences of rather petrogenic and pyrolytic PAH
contaminations were noticed in the harbors due to petroleum products deliveries and fuel combustion emissions from the ships
staying alongside the quays. 相似文献
499.
Isobe T Takada H Kanai M Tsutsumi S Isobe KO Boonyatumanond R Zakaria MP 《Environmental monitoring and assessment》2007,135(1-3):423-440
A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals
(EDCs) utilizing mussels as sentinel organisms was conducted in South and Southeast Asia as a part of the Asian Mussel Watch
project. Green mussel (Perna viridis) samples collected from a total of 48 locations in India, Indonesia, Singapore, Malaysia, Thailand, Cambodia, Vietnam, and
the Philippines during 1994–1999 were analyzed for PAHs, EDCs including nonylphenol (NP), octylphenol (OP) and bisphenol A
(BPA), and linear alkylbenzenes (LABs) as molecular markers for sewage. Concentrations of NP ranged from 18 to 643 ng/g-dry
tissue. The highest levels of NP in Malaysia, Singapore, the Philippines, and Indonesia were comparable to those observed
in Tokyo Bay. Elevated concentrations of EDCs were not observed in Vietnam and Cambodia, probably due to the lower extent
of industrialization in these regions. No consistent relationship between concentrations of phenolic EDCs and LABs were found,
suggesting that sewage is not a major source of EDCs. Concentrations of PAHs ranged from 11 to 1,133 ng/g-dry, which were
categorized as “low to moderate” levels of pollution. The ratio of methylphenanthrenes to phenanthrene (MP/P ratio) was >1.0
in 20 out of 25 locations, indicating extensive input of petrogenic PAHs. This study provides a bench-mark for data on the
distribution of anthropogenic contaminants in this region, which is essential in evaluating temporal and spatial variation
and effect of future regulatory measures. 相似文献
500.
K. Bruce Jones Anne C. Neale Maliha S. Nash Kurt H. Riitters James D. Wickham Robert V. O'Neill Rick D. van Remortel 《Environmental monitoring and assessment》2000,63(1):159-174
Using a new set of landscape indicator data generated by the U.S.EPA, and a comprehensive breeding bird database from the National Breeding Bird Survey, we evaluated associations between breeding bird richness and landscape characteristics across the entire mid-Atlantic region of the United States. We evaluated how these relationships varied among different groupings (guilds) of birds based on functional, structural, and compositional aspects of individual species demographics. Forest edge was by far the most important landscape attribute affecting the richness of the lumped specialist and generalist guilds; specialist species richness was negatively associated with forest edge and generalist richness was positively associated with forest edge. Landscape variables (indicators) explained a greater proportion of specialist species richness than the generalist guild (46% and 31%, respectively). The lower value in generalists may reflect finer-scale distributions of open habitat that go undetected by the Landsat satellite, open habitats created by roads (the areas from which breeding bird data are obtained), and the lumping of a wide variety of species into the generalist category. A further breakdown of species into 16 guilds showed considerable variation in the response of breeding birds to landscape conditions; forest obligate species had the strongest association with landscape indicators measured in this study (55% of the total variation explained) and forest generalists and open ground nesters the lowest (17% of the total variation explained). The variable response of guild species richness to landscape pattern suggests that one must consider species' demographics when assessing the consequences of landscape change on breeding birds. 相似文献