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211.
Greenhouse gas emissions assessments for site cleanups typically quantify emissions associated with remediation and not those from contaminant biodegradation. Yet, at petroleum spill sites, these emissions can be significant, and some remedial actions can decrease this additional component of the environmental footprint. This article demonstrates an emissions assessment for a hypothetical site, using the following technologies as examples: excavation with disposal to a landfill, light nonaqueous‐phase liquid (LNAPL) recovery with and without recovered product recycling, passive bioventing, and monitored natural attenuation (MNA). While the emissions associated with remediation for LNAPL recovery are greater than the other considered alternatives, this technology is comparable to excavation when a credit associated with product recycling is counted. Passive bioventing, a green remedial alternative, has greater remedial emissions than MNA, but unlike MNA can decrease contaminant‐related emissions by converting subsurface methane to carbon dioxide. For the presented example, passive bioventing has the lowest total emissions of all technologies considered. This illustrates the value in estimating both remediation and contaminant respiration emissions for petroleum spill sites, so that the benefit of green remedial approaches can be quantified at the remedial alternatives selection stage rather than simply as best management practices. ©2015 Wiley Periodicals, Inc.  相似文献   
212.
ASTM E2137 (Standard Guide for Estimating Monetary Costs and Liability for Environmental Matters, or E2137) is the guidance for developing estimates of future environmental costs. E2137 provides a hierarchy of cost estimation approaches, and expresses an explicit preference for the use of probabilistic cost analysis to develop expected values for environmental costs. Dr. Ram and his colleagues have published an article (Remediation Journal, Autumn 2013) which rejects the use of EV analysis, arguing that while “good in principle” it has little practical value because it is nearly impossible to develop supportable probabilities. The E2137 principles and processes have been used for more than a decade in the context of addressing future environmental costs, yet their view of E2137 renders the standard meaningless. We conclude that the deficiency is not in the ASTM standard, and that when properly constructed, probabilistic analyses can be used to develop expected values with supportable probabilities. ©2015 Wiley Periodicals, Inc.  相似文献   
213.
Disinfectants are added to swimming pools to kill harmful pathogens. Although liquid chlorine(sodium hypochlorite) is the most commonly used disinfectant, alternative disinfection techniques like electrochemically generated mixed oxidants or electrochemically generated chlorine, often referred to as salt water pools, are growing in popularity. However, these disinfectants react with natural organic matter and anthropogenic contaminants introduced to the pool water by swimmers to form disinfectio...  相似文献   
214.
Journal of Material Cycles and Waste Management - The use of lignocellulosic fibers as fillers in polymer matrices has aroused the interest of the scientific community and industrial sectors. In...  相似文献   
215.
Different livestock feeds manipulations have been reported to reduce the total P concentration in manure. Information on the influence of these dietary manipulation strategies on the forms of P in manure is, however, limited. This study was, therefore, conducted to investigate the effect of diet manipulation through feed micronization and enzyme supplementation on the forms of P in swine manure. Eight growing pigs were fed four diets: barley-raw pea (BRP), barley-micronized pea (BMP), barley-raw pea with enzyme (BRPE), and barley-micronized pea with enzyme (BMPE) in a 4 x 4 Latin square design. Because we are interested in the effect of enzyme cocktail and pea micronization on manure P, we did not reduce the non-phytate P with enzyme addition in this study. The fecal material and urine were collected and analyzed for total P. Fecal material was fractionated to determine the total P in H2O-, NaHCO3-, NaOH-, and HCl-extractable fractions. The total P in the residual fractions was also determined. About 98% of the total P excreted by the pigs was found in the fecal material. Inclusion of micronized pea in pig diet did not have any significant effect (p > 0.1) on either the total P or the different P fractions in the manure. The labile P (the sum of H2O-P and NaHCO3-P) was significantly reduced (p < 0.05) by the addition of enzyme to swine diets. Pigs fed the BRPE and BMPE had 14 and 18% lower labile P, respectively, compared with pigs fed the BRP. Enzyme addition to pig diets reduced not only the total P in manure, but also the labile P fraction, which is of great environmental concern. Thus, the potential of P loss to runoff and the subsequent eutrophication can be reduced by enzyme addition to pig diets.  相似文献   
216.
Because catchment characteristics determine sediment and nutrient inputs to streams, upland disturbance can affect stream chemistry. Catchments at the Fort Benning Military Installation (near Columbus, Georgia) experience a range of upland disturbance intensities due to spatial variability in the intensity of military training. We used this disturbance gradient to investigate the effects of upland soil and vegetation disturbance on stream chemistry. During baseflow, mean total suspended sediment (TSS) concentration and mean inorganic suspended sediment (ISS) concentration increased with catchment disturbance intensity (TSS: R2= 0.7, p = 0.005, range = 4.0-10.1 mg L(-1); ISS: R2= 0.71, p = 0.004, range = 2.04-7.3 mg L(-1)); dissolved organic carbon (DOC) concentration (R2= 0.79, p = 0.001, range = 1.5-4.1 mg L(-1)) and soluble reactive phosphorus (SRP) concentration (R2= 0.75, p = 0.008, range = 1.9-6.2 microg L(-1)) decreased with increasing disturbance intensity; and ammonia (NH4+), nitrate (NO3-), and dissolved inorganic nitrogen (DIN) concentrations were unrelated to disturbance intensity. The increase in TSS and ISS during storms was positively correlated with disturbance (R2= 0.78 and 0.78, p = 0.01 and 0.01, respectively); mean maximum change in SRP during storms increased with disturbance (r = 0.7, p = 0.04); and mean maximum change in NO3- during storms was marginally correlated with disturbance (r = 0.58, p = 0.06). Soil characteristics were significant predictors of baseflow DOC, SRP, and Ca2+, but were not correlated with suspended sediment fractions, any nitrogen species, or pH. Despite the largely intact riparian zones of these headwater streams, upland soil and vegetation disturbances had clear effects on stream chemistry during baseflow and stormflow conditions.  相似文献   
217.
This paper reviews the effects of past forest management on carbon stocks in the United States, and the challenges for managing forest carbon resources in the 21st century. Forests in the United States were in approximate carbon balance with the atmosphere from 1600-1800. Utilization and land clearing caused a large pulse of forest carbon emissions during the 19th century, followed by regrowth and net forest carbon sequestration in the 20th century. Recent data and knowledge of the general behavior of forests after disturbance suggest that the rate of forest carbon sequestration is declining. A goal of an additional 100 to 200 Tg C/yr of forest carbon sequestration is achievable, but would require investment in inventory and monitoring, development of technology and practices, and assistance for land managers.  相似文献   
218.
This article discusses the system of classification of forest types used by the Pwo Karen in Thung Yai Naresuan Wildlife Sanctuary in western Thailand and the role of nontimber forest products (NTFPs), focusing on wild food plants, in Karen livelihoods. The article argues that the Pwo Karen have two methods of forest classification, closely related to their swidden farming practices. The first is used for forest land that has been, or can be, swiddened, and classifies forest types according to growth conditions. The second system is used for land that is not suitable for cultivation and looks at soil properties and slope. The article estimates the relative importance of each forest type in what concerns the collection of wild food plants. A total of 134 wild food plant species were recorded in December 2004. They account for some 80–90% of the amount of edible plants consumed by the Pwo Karen, and have a base value of Baht 11,505 per year, comparable to the cash incomes of many households. The article argues that the Pwo Karen reliance on NTFPs has influenced their land-use and forest management practices. However, by restricting the length of the fallow period, the Thai government has caused ecological changes that are challenging the ability of the Karen to remain subsistence oriented. By ignoring shifting cultivators’ dependence on such products, the involvement of governments in forest management, especially through restrictions imposed on swidden farming practices, is likely to have a considerable impact on the livelihood strategies of these communities.  相似文献   
219.
From 1992–1996, 3204 artificial roosts of 9 types were placed in woodlots near Indianapolis International Airport in an effort to provide habitat for the federally-endangered Indiana myotis (Myotis sodalis) and to determine the feasibility of using these structures to manage bats in a rapidly developing suburban area. We surveyed these structures at least annually during 1992–1999 and found only northern myotis (Myotis septentrionalis) regularly using the structures. Four other species were occasionally found using structures including big brown bats (Eptesicus fuscus, n = 14 individuals), little brown myotis (Myotis lucifugus, n = 2), Indiana myotis (Myotis sodalis, n = 2), and one silver-haired bat (Lasionycteris noctivagans). Single, triple, and Missouri-style batboxes were almost always used, rather than the six other types of experimental roosts that had been in place. However, after 10 years in place, it appears that Indiana bats are acclimated to boxes, as 6 of them were being used rather regularly by Indiana myotis. Bat boxes can provide roosting habitat for some species under conditions where few suitable roosts exist, but assuring an abundance of natural habitats is usually more desirable for conservation of tree-roosting bats.  相似文献   
220.
We report the preparation of poly(3,4-ethylene dioxythiophene) (PEDOT)-modified polyvinylidene fluoride electrospun fibers and their use as a novel adsorbent material for the removal of the anionic dye Methyl Orange (MO) from aqueous media. This novel adsorbent material can be used to selectively remove MO on a wide pH range (3.0–10.0), with a maximum capacity of 143.8 mg/g at pH 3.0. When used in a recirculating filtration system, the maximum absorption capacity was reached in a shorter time (20 min) than that observed for batch mode experiments (360 min). Based on the analyses of the kinetics and adsorption isotherm data, one can conclude that the predominant mechanism of interaction between the membrane and the dissolved dye molecules is electrostatic. Besides, considering the estimated values for the Gibbs energy, and entropy and enthalpy changes, it was established that the adsorption process is spontaneous and occurs in an endothermic manner. The good mechanical and environmental stability of these membranes allowed their use in at least 20 consecutive adsorption/desorption cycles, without significant loss of their characteristics. We suggest that the physical-chemical characteristics of PEDOT make these hybrid mats a promising adsorbent material for use in water remediation protocols and effluent treatment systems.  相似文献   
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