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1.
Thuli N. Mdluli Coleen H. Vogel 《Mitigation and Adaptation Strategies for Global Change》2010,15(3):205-222
South Africa faces several development challenges including those linked to climate change. Energy usage in South Africa,
for example, is already constrained because of a range of development challenges (the dependence on cheap coal as a heating
source; energy availability; access; affordability of alternative energy sources; and a range of health impacts, including
air pollution). Notwithstanding calls for a transition to a low carbon economy, there have been few, recent assessments in
South Africa of the costs associated with such a transition, particularly the social and economic costs for the poor who use
energy in a variety of ways. In this paper we focus on trying to unravel some of the complex energy-use behaviour including
understanding what drives consumers in resource-poor areas to choose and use persistently risky energy options. Analysis of
qualitative data in two township areas, Doornkop and Kwaguqa, shows that township households, whether electrified or not,
continue to burn coal. In both study areas, an estimated 80% of electrified households burn coal for space heating and cooking
and also make use of multiple fuel sources for a range of activities. Although the major obstacles preventing people from
discontinuing domestic coal combustion are poverty, the ready availability and social acceptability of coal together with
other social customs cannot be underrated. This paper therefore highlights some of the persistent challenges associated with
sustainable energy transitions in South Africa including implications for improved mitigation and adaptation for the energy
sector in wider climate change efforts. 相似文献
2.
C. E. Barthel JR. 《Journal of the Air & Waste Management Association (1995)》2013,63(11):475-478
This is a report on Meetings of Representatives of National Air Pollution Preventions Associations to Consider the Establishment of an International Union, held in Washington, D. C, June 18–19, 1964 and Houston, Texas, June 21–22, 1964. 相似文献
3.
MIRIAM H. INOUE RUBEM S. OLIVEIRA JR. JUSSARA B. REGITANO CÁSSIO A. TORMENA JAMIL CONSTANTIN VALDEMAR L. TORNISIELO 《Journal of environmental science and health. Part. B》2013,48(5):605-621
The objective of this study was to investigate the behavior of sorption and desorption of the herbicides atrazine (6-chloro-N 2-ethyl-N 4-isopropyl-1,3,5-triazine-2,4-diamine) and diuron [3-(3,4-dichlorophenyl)-1,1-dimethyleurea] in soil samples from a typical lithosequence located in the municipality of Mamborê (PR), southern Brazil. Five concentrations of 14C-atrazine and 14C-diuron were used for both herbicides (0.48, 0.96, 1.92, 3.84, and 7.69 mg L?1). Sorption of both herbicides correlated positively with the organic carbon and clay content of the soil samples. Sorption isotherms were well described by the Freundlich model. The slope values of the isotherm (N) ranged from 0.84 to 0.90 (atrazine) and from 0.75 to 0.79 (diuron) for the lithosequence samples. Sorption of diuron was high regardless of the soil texture or the concentration added. The desorption isotherms for atrazine and diuron showed good fit to the Freundlich equation (R 2 ≥ 0,87). Atrazine slope values for the desorption isotherms were similar for the different concentrations and were much lower than those observed for the sorption isotherms. Significant hysteresis was observed in the herbicide desorption. When the two herbicides were compared, it was found that diuron (N = 0.06–0.22) presented more pronounced hysteresis than atrazine. The results showed that, quantitatively, a greater atrazine fraction applied to these soils remains available to be leached in the soil profile, as compared to diuron. 相似文献
4.
H. H. Meredith JR 《Journal of the Air & Waste Management Association (1995)》2013,63(11):719-723
An American Petroleum Institute study of desulfurization of Caribbean fuel oil was completed in February 1967. The report is unique in that proprietary information was made available to the contractor, the Bechtel Corp., by task force members and licensors of desulfurization processes. Thus confidential information never before available to a single organization was used to develop feasibility and incremental costs of various processes for desulfurization. The report provides needed guideposts for decision-making by governmental units as well as by industry. Incremental costs are presented for intermediate levels of desulfurization from the normal level for Caribbean heavy fuel oil of 2.6% down to 0.5%, as well as the sensitivity of costs to sulfur credits and to rate of recovery of invested capital. Degree of justifiable confidence in the various data is discussed. Effects of desulfurization on other characterisics of the fuel oil are also discussed. 相似文献
5.
Kate M. Munson Richard M. Vogel John L. Durant 《Journal of the American Water Resources Association》2018,54(2):527-542
We investigate the sensitivity of phosphorus loading (mass/time) in an urban stream to variations in climate using nondimensional sensitivity, known as elasticity, methods commonly used by economists and hydrologists. Previous analyses have used bivariate elasticity methods to represent the general relationship between nutrient loading and a variable of interest, but such bivariate relations cannot reflect the complex multivariate nonlinear relationships inherent among nutrients, precipitation, temperature, and streamflow. Using fixed‐effect multivariate regression methods, we obtain two phosphorus models (nonparametric and parametric) for an urban stream with high explanatory power that can both estimate phosphorus loads and the elasticity of phosphorus loading to changes in precipitation, temperature, and streamflow. A case study demonstrates total phosphorus loading depends significantly on season, rainfall, combined sewer overflow events, and flow rate, yet the elasticity of total phosphorus to all these factors remains relatively constant throughout the year. The elasticity estimates reported here can be used to examine how nutrient loads may change under future climate conditions. 相似文献
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8.
Utility of North Atlantic Right Whale Museum Specimens for Assessing Changes in Genetic Diversity 总被引:2,自引:0,他引:2
Howard C. Rosenbaum †§§ Mary G. Egan Phillip J. Clapham ‡ Robert L. Brownell JR. § Sobia Malik Moira W. Brown ††‡‡ Bradley N. White Peter Walsh † and Rob Desalle 《Conservation biology》2000,14(6):1837-1842
Abstract: We examined six historical specimens of the endangered North Atlantic right whale ( Eubalaena glacialis ) using DNA isolated from documented baleen plates from the late nineteenth and early twentieth centuries. Sequences from the mitochondrial DNA (mtDNA) control region from these samples were compared with those from a near-exhaustive survey (269 of approximately 320 individuals) of the remaining right whales in the western North Atlantic Ocean. Our results suggest that there has been only relatively modest change in maternal lineage diversity over the past century in the North Atlantic right whale population. Any significant reduction in genetic variation in the species most likely occurred prior to the late nineteenth century. One historical specimen was from the last documented female capable of propagating one of the maternal lineages in the population today; no females in the existing population have been found to carry this mtDNA haplotype. Analysis of the only specimens from the eastern North Atlantic right whale population ever to be examined revealed that eastern and western North Atlantic right whales may not have been genetically differentiated populations. Loss of gene diversity experienced by North Atlantic right whales over the last century has been modest, and the six decades of protection have been successful in maintaining much of the maternal lineage diversity that was present in the late nineteenth century. 相似文献
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10.
Abstract: Starch-gel electrophoresis was used to screen 101 bison from Badlands National Park, South Dakota, for variation at 24 genetic loci. The population was descended from founder groups of about 6 and 3 individuals, separated geographically for a minimum of 64 years. The purpose of this study was (1) to estimate levels of genic variability in this bison population, (2) to assess the extent to which descendents of the two founder groups differ genetically, and (3) to compare the genetic characteristics of the Badlands population with other bison populations. The Badlands herd was found to be polymorphic for only a single locus (MDH–1). Descendents of the founder groups were homogeneous with respect to allelic and genotypic frequencies at this locus. The MDH–1 polymorphism has not been observed in other bison populations, while several polymorphism reported in other bison populations were not detected in the Badlands herd. A mean heterozygosity of 0.012 was observed in the Badlands herd; this value is lower than that typically reported for mammals, though not as low as heterozygosities seen in other populations that have passed through severe bottlenecks in size. These results underscore the need for genetic data in planning breeding programs for species in captivity or managed in isolate reserves. 相似文献