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141.
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
142.
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
143.
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
144.
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
145.
Herbert C. Mckee William L. Rollwitz 《Journal of the Air & Waste Management Association (1995)》2013,63(4):338-340
Air pollution forecasting is not a new field but is certainly an area with only modest development since its early beginnings. Because ozone Is not a source emission but instead is formed from precursors, ozone episodes should be more readily forecasted than other pollutants by simply monitoring the precursors. The ozone empirical model developed within the course of this study is very site specific, therefore the major goal of the study was to establish the techniques which can be used to develop an ozone forecasting model for specific monitoring networks. The results of using the ozone forecasting model showed that even though errors as high as 25 % occurred the typical error In forecasting was in the 5-10% range. 相似文献
146.
Charles S. Maneri P. E. William H. Megonnell P. E. 《Journal of the Air & Waste Management Association (1995)》2013,63(5):374-377
The proposed By-law changes have been suggested over the last two years. They are basically housekeeping changes which correct the language, eliminate duplications, and clarify the dates for the receipt and acceptance of the ballots for nominees for the Board. The major revision proposed is in Article XV of the Technical Council which was necessitated by the new structure of the Technical Council approved by the Board of Directors in June 1970. 相似文献
147.
148.
Ralph I. Larsen Ph.D. William W. Stalker Charles R. Claydon 《Journal of the Air & Waste Management Association (1995)》2013,63(11):529-534
This progress report describes the National Air Pollution Technical Information Center currently under development in the Division of Air Pollution, Public Health Service. It briefly reviews the report "Science, Government, and Information" (Weinberg Report) and the White House delegation of responsibility to the Department of Health, Education, and Welfare for handling air pollution technical information. 相似文献
149.
150.