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191.
192.
Viatcheslav Moutavtchi Jan Stenis William Hogland Antonina Shepeleva 《Journal of Material Cycles and Waste Management》2010,12(2):169-183
This article aims to develop a general model for the evaluation of ecological-economic efficiency that will serve as an information
support tool for decision making at the corporate, municipal, and regional levels. It encompasses cost-benefit analysis in
solid waste management by applying a sustainability promoting approach that is explicitly related to monetary measures. A
waste managements’ efficient decision (WAMED) model based on cost-benefit analysis is proposed and developed to evaluate the
ecological-economic efficiency of solid waste management schemes. The employment of common business administration methodology
tools is featured. A classification of competing waste management models is introduced to facilitate evaluation of the relevance
of the previously introduced WAMED model. Suggestions are made for how to combine the previously introduced EUROPE model,
based on the equality principle, with the WAMED model to create economic incentives to reduce solid waste management-related
emissions. A fictive case study presents the practical application of the proposed cost-benefit analysis-based theory to the
landfilling concept. It is concluded that the presented methodology reflects an integrated approach to decreasing negative
impacts on the environment and on the health of the population, while increasing economic benefits through the implementation
of solid waste management projects. 相似文献
193.
194.
Thomas WH 《Environmental management》2010,45(1):82-92
It has been proposed that indigenous societies can be models for the conservation of biodiversity. However, attempts at implementing
conservation-based development plans are being judged failures. In this article, I argue that these failures can be addressed
by translating indigenous knowledge into context that is mutually intelligible to both indigenous people and conservation
biologists. Drawing on sixteen months of ethnobiological fieldwork, this article uses indigenous knowledge to describe the
relationship of traditional life to biodiversity for the Hewa of Papua New Guinea’s Central Range. The island of New Guinea
is one of the planet’s last bastions of cultural and biological diversity. Using birds as an indicator of diversity, I argue
that more productive conservation policies will emerge when indigenous activities are viewed not as vehicles for establishing
equilibrium with the environment, but as a source of ecological disturbance. Although Hewa traditions currently play a significant
role in shaping this biologically diverse environment, their lifestyle is not necessarily a template for sustainability in
the future. 相似文献
195.
Gary Z. Whitten Gookyoung Heo Yosuke Kimura Elena McDonald-Buller David T. Allen William P.L. Carter Greg Yarwood 《Atmospheric environment (Oxford, England : 1994)》2010,44(40):5346-5355
Toluene is ubiquitous in urban atmospheres and is a precursor to tropospheric ozone and aerosol (smog). An important characteristic of toluene chemistry is the tendency of some degradation products (e.g., cresols and methyl-catechols) to form organic nitro and nitrate compounds that sequester NOx (NO and NO2) from active participation in smog formation. Explaining the NOx sinks in toluene degradation has made mechanism development more difficult for toluene than for many other organic compounds. Another challenge for toluene is explaining sources of radicals early in the degradation process. This paper describes the development of a new condensed toluene mechanism consisting of 26 reactions, and evaluates the performance of CB05 with this new toluene scheme (Toluene Update, TU) against 38 chamber experiments at 7 different environmental chambers, and provides recommendations for future developments. CB05 with the current toluene mechanism (CB05-Base) under-predicted the maximum O3 and O3 production rate for many of these toluene–NOx chamber experiments, especially under low-NOx conditions ([NOx]t=0 < 100 ppb). CB05 with the new toluene mechanism (CB05-TU) includes changes to the yields and reactions of cresols and ring-opening products, and showed better performance than CB05-Base in predicting the maximum O3, O3 formation rate, NOx removal rate and cresol concentration. Additional environmental chamber simulations with xylene–NOx experiments showed that the TU mechanism updates tended to improve mechanism performance for xylene. 相似文献
196.
Scott M. Payne William W. Woessner 《Journal of the American Water Resources Association》2010,46(5):1003-1023
Payne, Scott M. and William W. Woessner, 2010. An Aquifer Classification System and Geographical Information System-Based Analysis Tool for Watershed Managers in the Western U.S. Journal of the American Water Resources Association (JAWRA) 46(5):1003-1023. DOI: 10.1111/j.1752-1688.2010.00472.x Abstract: Aquifers and groundwater systems can be classified using a variety of independent methods to characterize geologic and hydraulic properties, the degree of connection with surface water, and geochemical conditions. In light of a growing global demand for water, an approach for classifying groundwater systems at the watershed scale is needed. A comprehensive classification system is proposed that combines recognized methods and new approaches. The purpose of classification is to provide groundwater professionals, policy makers, and watershed managers with a widely applicable and repeatable system that reduces sometimes cumbersome complex databases and analyzes to straightforward terminology and graphical representations. The proposed classification system uses basin geology, aquifer productivity, water quality, and the degree of groundwater/surface water connection as classification criteria. The approach is based on literature values, reference databases, and fundamental hydrologic and hydrogeologic principles. The proposed classification system treats dataset completeness as a variable and includes a tiered assessment protocol that depends on the quality and quantity of data. In addition, it assembles and catalogs groundwater information using a consistent set of nomenclature. It is designed to analyze and display results using Geographical Information System mapping tools. 相似文献
197.
Exporting natural capital: the foreign eco-footprint on Costa Rica and implications for sustainability 总被引:1,自引:0,他引:1
As the world economy ‘globalizes’, trade has become a major mechanism by which much of the human population supports its needs.
While trade in resource commodities (natural income) can increase the well-being of people in both exporting and importing
countries, it can also lead to depletion of natural capital and the loss of ecosystems integrity. In recent years, various
researchers have attempted to address this problem using a consumption-based perspective on ecological change. Their work
shows that the loss of ecosystem integrity in almost any region of the world can be attributed to both local and international
consumer demand. This paper illustrates the utility of modified eco-footprint analysis in assessing export-related ecological
change in Costa Rica. We quantify ecological footprint of consumers around the world on the productive ecosystems of Costa
Rica, document the changing character of this footprint and highlight some of the linkages between production for export in
Costa Rica and ecological degradation. We then discuss the implications of the increasing trade-based entanglement of nations
for ecosystems and global sustainability. 相似文献
198.
Yujing Yang Changxiao Li Jian Li Rebecca Schneider William Lamberts 《Environmental science and pollution research international》2013,20(10):7112-7123
Pterocarya stenoptera is a native deciduous tree species and a candidate for reforestation in the riparian zones of the Three Gorges Reservoir Region of Yangtze River in China. Water treatments of continuous flooding (CF) and periodic flooding–drought (PF) were applied to examine the growth dynamics of 4-month-old P. stenoptera seedlings and its effects on soil chemical properties. Results showed that P. stenoptera seedlings in both CF and PF significantly decreased leaf biomass accumulation and the height and diameter growth as compared to that in control (CK; treatment with well-watered, well-drained soil), respectively. There was no significant difference in stem biomass among the three groups, but root biomass in PF showed severe reduction compared to that in both CK and CF. Total biomass in PF was significantly decreased compared to that in CK, but comparable to that in CF. Furthermore, no significant difference was found between CF and CK in total biomass. Water treatments in the unplanted soil pots significantly influenced soil pH, soil organic matter (OM), total nitrogen (TN), and alkali hydrolysable nitrogen (AN) contents, in contrast to no significant effects in total phosphorus (TP), total potassium (TK), available phosphorus (AP), and available potassium (AK) contents. In P. stenoptera soils, there were significant effects by water treatment, time, and treatment × time in the eight tested soil chemical properties, except treatment in TK and time effect in OM content. Compared to unplanted soils, the growth of P. stenoptera seedlings significantly increased soil pH value and OM, TN, TP, and TK contents, while decreasing AN, AP, and AK contents in CK group, augmented the mean value of each of the tested soil chemical properties with an exception of AK content in CF group, and increased soil pH value and TN, AN, TP, and AP contents with no significant differences in OM, TK, and AK contents in PF group. Given the fact that TN and TP contents significantly increased in P. stenoptera soils as compared to those in unplanted soils, growth of P. stenoptera seedlings should be a successful candidate for restoration within the highly dynamic hydrologic zone of the riparian zones of the Three Gorges Reservoir Region. 相似文献
199.
Flagships are one conservation education tool. We present a proposed flagship species fleet for environmental education in central Chile. Our methods followed recent flagship guidelines. We present our selection process and a detailed justification for the fleet of flagship species that we selected. Our results are a list of eight flagship species forming a flagship fleet, including two small- and medium-sized mammals, the degu (Octodon degus) and the culpeo fox (Lycalopex culpeaus), two birds, the turca (Pteroptochos megapoidius) and the burrowing owl (Athene cunicularia), the Chilean iguana (Calopistes palluma), the tarantula (Grammostola mollicoma), and two trees, the litre (Lithrea caustica) and the espino (Acacia caven). We then describe how these flagships can be deployed most effectively, describing their audience, effective narrative frames, and modes of presentation. We conclude that general selection rules paired with social science background data allow for an efficient selection process. 相似文献
200.
William G. Christy 《Journal of the Air & Waste Management Association (1995)》2013,63(2):126-174
Bottom ash is a waste material from coal-fired power plants, and it is known to contain elements that are potentially toxic at high concentration levels when disposed in landfills. This study investigates the use of bottom ash as a partial substitute sorbent for wet flue gas desulfurization (FGD) processes by focusing on its leaching kinetics in adipic acid. This was studied basing on the shrinking core model that was applied to the experimental data obtained by the authors presented at the International Conference on Industrial, Manufacturing, Automation and Mechanical Engineering, Johannesburg, South Africa, November 27–28, 2013) on dissolution of bottom ash. The leaching rate constant was obtained from different reaction variables, namely, temperature, pH, acid concentration, and solid-to-liquid ratio, that could affect the leaching process. The solid sample of bottom ash was characterized at different leaching periods using X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that solid-to-liquid ratio had a significant effect on the leaching rate constant when compared with other variables. The leaching kinetics showed that diffusion through the product layer was the rate-controlling step during leaching, and the activation energy for the process was found to be 18.92 kJ/mol.Implications:?The use of coal bottom ash waste as a sorbent substitute in wet flue gas desulfurization (FGD) has both economic and environmental advantages. This is because it is a waste from coal-fired thermal power plant and this study has proven that it can leach out a substantial amount of calcium ions for wet FGD process. This will abate anthropogenic pollution due to landfill disposal of bottom ash wastes and also reduce sulfur dioxide emissions. 相似文献