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201.
The current trend in foreign aid is toward small-scale sustainable development projects in partnership with defined communities.
However, these projects are subject to the influences of self-interested human behavior, poorly defined community structures
and resources and organizational constraints that can prevent full realization of development models. Under these constraints,
attempting participatory community development models to the exclusion of other techniques may not be the most effective way
to achieve positive change. Instead, development agencies should consider adopting other proven elements of development in
combination with the spirit of community development to achieve a positive impact within the community and organizational
structures and ensure accountability for success. A small-scale attempted, sustainable development case study in Rwanda is
reviewed, as well as a new concept for larger scale development integrating ‘carbon credits’. Additionally, a development
accreditation organization is proposed to ensure additional accountability in this field. 相似文献
202.
Bernadette Teufl Gabriele Weigelhofer Jennifer Fuchsberger Thomas Hein 《Environmental science and pollution research international》2013,20(3):1781-1793
Intensive agricultural land use imposes multiple pressures on streams. More specifically, the loading of streams with nutrient-enriched soil from surrounding crop fields may deteriorate the sediment quality. The current study aimed to find out whether stream restoration may be an effective tool to improve the sediment quality of agricultural headwater streams. We compared nine stream reaches representing different morphological types (forested meandering reaches vs. deforested channelized reaches) regarding sediment structure, sedimentary nutrient and organic matter concentrations, and benthic microbial respiration. Main differences among reach types were found in grain sizes. Meandering reaches featured larger mean grain sizes (50–70 μm) and a thicker oxygenated surface layer (8 cm) than channelized reaches (40 μm, 5 cm). Total phosphorous amounted for up to 1,500 μg?g?1 DW at retentive channelized reaches and 850–1,050 μg?g?1 DW at the others. While N-NH4 accumulated in the sediments (60–180 μg?g?1 DW), N-NO3 concentrations were generally low (2–5 μg?g?1 DW). Benthic respiration was high at all sites (10–20 g O2 m?2?day?1). Our study shows that both hydromorphology and bank vegetation may influence the sediment quality of agricultural streams, though effects are often small and spatially restricted. To increase the efficiency of stream restoration in agricultural landscapes, nutrient and sediment delivery to stream channels need to be minimized by mitigating soil erosion in the catchment. 相似文献
203.
João Paulo Machado Torres Claudio Leite Thomas Krauss Roland Weber 《Environmental science and pollution research international》2013,20(4):1958-1965
In 1997, the Polychlorinated dibenzo-para-dioxin (PCDD)/Polychlorinated dibenzofuran (PCDF) concentrations in dairy products in Germany and other European countries increased. The PCDD/PCDF source was contaminated lime used in Brazilian citrus pulp pellets. The contaminated lime was mined from an industrial dump site. However, the detailed origin of the PCDD/PCDFs in the lime was not revealed. This paper investigates the contamination origin and describes the link between lime milk from the dumpsite of a chlorine/organochlorine industry and the contaminated lime. The contaminated lime stem from mining at the corporate landfill of Solvay Indupa in Sao Paulo. The landfill was used for 40 years for deposition of production residues and closed in 1996. The factory operated/operates at least two processes with potentially high PCDD/PCDFs releases namely the oxychlorination process for production of ethylene dichloride (EDC) and the chlor-alkali process. The main landfilled waste was lime milk (1.4 million tons) from the vinyl chloride monomer production (via the acetylene process) along with residues from other processes. The PCDD/PCDF fingerprint revealed that most samples from the chemical landfill showed an EDC PCDD/PCDF pattern with a characteristic octachlorodibenzofuran dominance. The PCDD/PCDF pattern of a Rio Grande sediment samples downstream the facility showed a chlor-alkali pattern with a minor impact of the EDC pattern. The case highlights that PCDD/PCDF- and persistent organic pollutants-contaminated sites need to be identified in a comprehensive manner as required by the Stockholm Convention (article 6) and controlled for their impact on the environment and human health. Landfill mining and reuse of materials from contaminated deposits should be prohibited. 相似文献
204.
Angélique Lazartigues Marielle Thomas Cécile Cren-Olivé Jean Brun-Bellut Yves Le Roux Damien Banas Cyril Feidt 《Environmental science and pollution research international》2013,20(1):117-125
Residues of pesticides in fish farming productions from barrage ponds are seldom studied in spite of increasing health questionings and environmental concerns. The purpose of this study is to establish the pesticide contamination profiles of sediments and edible fish from five ponds in Northeastern France. Multi-residues method and liquid chromatography–tandem mass spectrometry analysis were used to quantify 13 pesticides (azoxystrobin, carbendazim, clomazone, diflufenican, dimethachlor, fluroxypyr, iprodion, isoproturon, mesosulfuron-methyl, metazachlor, napropamid, quizalofop and thifensulfuron-methyl). Ten sediments and 143 muscles samples were analysed, corresponding to two successive fishing campaigns (first fishing date and second fishing date (P2), about 1 year later) on five sites (noted C-0, C-25, C-45, C-75 and C-85 to express the increasing gradient of crop area). Isoproturon was present in all sediments samples (1.8–56.4 μg/kg dry weight). During P2 period, carbendazim was quantified in the fish of site C-0 (0.09?±?0.02, 0.2?±?0.1 and 0.17?±?0.06 μg/kg wet weight (ww) for roach, carp and perch, respectively). Metazachlor was only quantified in perch of the site C-25 (0.13?±?0.02 μg/kg ww). Concentrations of isoproturon were similar for the sites C-45 and C-75 with 0.4?±?0.1 and 0.75?±?0.06 μg/kg ww for carp and perch, respectively. Contamination of fish reflected generally concentrations in surroundings. Isoproturon was the most concentrated and its main source was water for perch while carp was exposed through both water and sediments, highlighting their life strategies in pond. 相似文献
205.
Sarah Schönbrodt-Stitt Anna Bosch Thorsten Behrens Heike Hartmann Xuezheng Shi Thomas Scholten 《Environmental science and pollution research international》2013,20(10):6917-6933
In densely populated countries like China, clean water is one of the most challenging issues of prospective politics and environmental planning. Water pollution and eutrophication by excessive input of nitrogen and phosphorous from nonpoint sources is mostly linked to soil erosion from agricultural land. In order to prevent such water pollution by diffuse matter fluxes, knowledge about the extent of soil loss and the spatial distribution of hot spots of soil erosion is essential. In remote areas such as the mountainous regions of the upper and middle reaches of the Yangtze River, rainfall data are scarce. Since rainfall erosivity is one of the key factors in soil erosion modeling, e.g., expressed as R factor in the Revised Universal Soil Loss Equation model, a methodology is needed to spatially determine rainfall erosivity. Our study aims at the approximation and spatial regionalization of rainfall erosivity from sparse data in the large (3,200 km2) and strongly mountainous catchment of the Xiangxi River, a first order tributary to the Yangtze River close to the Three Gorges Dam. As data on rainfall were only obtainable in daily records for one climate station in the central part of the catchment and five stations in its surrounding area, we approximated rainfall erosivity as R factors using regression analysis combined with elevation bands derived from a digital elevation model. The mean annual R factor (R a) amounts for approximately 5,222 MJ?mm?ha?1?h?1?a?1. With increasing altitudes, R a rises up to maximum 7,547 MJ?mm ha?1?h?1 a?1 at an altitude of 3,078 m a.s.l. At the outlet of the Xiangxi catchment erosivity is at minimum with approximate R a?=?1,986 MJ?mm?ha?1?h?1?a?1. The comparison of our results with R factors from high-resolution measurements at comparable study sites close to the Xiangxi catchment shows good consistance and allows us to calculate grid-based R a as input for a spatially high-resolution and area-specific assessment of soil erosion risk. 相似文献
206.
Martina Periša Sandra Babić Irena Škorić Tobias Frömel Thomas P. Knepper 《Environmental science and pollution research international》2013,20(12):8934-8946
Once released into the aquatic environment, pharmaceuticals may undergo different degradation processes. Photodegradation, for example, might be an important elimination process for light-sensitive pharmaceuticals, such as antibiotics. In this study, the fate of sulfonamides (sulfamethazine, sulfadiazine, and sulfamethoxazole) and their N 4-acetylated metabolites (N 4-acetylsulfadiazine, N 4-acetylsulfamethazine, and N 4-acetylsulfamethoxazole) under simulated sunlight irradiation was investigated. The irradiation resulted in total or almost total degradation (88 to 98 %) of the pharmaceuticals tested, except for sulfamethazine (52 %), during 24 h of irradiation. The photoproducts of all investigated pharmaceuticals have been analyzed using high-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry. Structure elucidation performed from photodegradation products of both, sulfonamides and their N 4-acetylated metabolites, clearly showed two major formation pathways. These were cleavage of the sulfonamide bond as well as SO2 extrusion. In total, nine photoproducts were elucidated. Among these photoproducts, the tautomers of sulfamethoxazole and desulfonated products of sulfadiazine and sulfamethazine were also present. Tautomers of sulfadiazine and sulfamethazine have been characterized here for the first time as well as some photoproducts of sulfadiazine, sulfametoxazole, and their metabolites N 4-acetylsulfadiazine and N 4-acetylsulfametoxazole. The obtained results are an important piece in the complex puzzle for assessing the environmental fate of sulfonamides and their metabolites in the environment. 相似文献
207.
Mover D. Thomas 《Journal of the Air & Waste Management Association (1995)》2013,63(12):517-520
The current literature on the role of sulfur dioxide in air pollution 相似文献
208.
H. P. Sanderson R. Thomas Morris Katz 《Journal of the Air & Waste Management Association (1995)》2013,63(6):328-330
Field experience with the lead acetate impregnated paper tape sampler has indicated that large errors may arise in this method due to fading of the color of the precipitated lead sulfide spots. This fading is due to the action of light, sulfur dioxide, ozone, on other substances capable of oxidizing lead sulfide. The moisture content or relative humidity of the air sample must be maintained at an appropriate level to ensure reaction with the impregnated paper tape. The effects of the factors have been investigated in laboratory experiments with known concentrations of H2S. A number of antioxidants were studied in relation to the stability of the resultant spots to light and oxidation Orthophenyl phenol was found to be the most effective antioxidant for this purpose. A number of necessary precautions to be employed in the use of the lead acetate method are recommended and the limitations are discussed. 相似文献
209.
Thomas E. Kreichelt Thomas G. Keller 《Journal of the Air & Waste Management Association (1995)》2013,63(8):640-645
Studies of roof monitor emissions are conducted for two reasons: (1) to obtain design data necessary to engineer control systems to meet existing regulations, and (2) to determine projected control costs which can influence present day proposals for process change. Heated wire anemometers and rotating vane anemometers have been selected for velocity measurements, and high-volume air samplers have been selected to collect the particulate sample. Evaluation of other types of velocity sensing devices are described in the paper. Roof monitor studies must be preceded by a preliminary survey to allow the project engineer to determine the test sampling locations and specific methodology necessary for the given study, and to allow the engineer to determine the type of safety equipment, scaffolds, and power requirements necessary to complete the study. Field tests are conducted by operating a number of high-volume air samplers simultaneously while at the same time measuring the velocity of the gas through the monitor opening. Curves of particulate concentration and velocity as a function of monitor length are constructed. The concentration and velocity curves are then integrated together and the resultant curve is multiplied by the monitor width to determine a curve of mass emission rate as a function of monitor length. The total mass emission rate is represented by the area under the mass emission rate curve. Procedures for calibrating the anemometers and correcting for the effect of power fluctuation on the high-volume sampler operation are described. Data evaluation procedures and discussion of test error are also described. A study can cost between 10 and 20 thousand dollars, including the cost of manpower and the cost of scaffolds, power, cables, etc. It can take four months or more to conduct a study, from the preliminary survey phase through the report phase. 相似文献
210.
Timothy M. Gilmore Thomas R. Hanna 《Journal of the Air & Waste Management Association (1995)》2013,63(5):535-539
The so-called “Six Month Study” of the air toxics problem in the United States was initiated in November 1983 by the U.S. Environmental Protection Agency. The study focused on the magnitude, nature, and distribution of the problem—three major issues that were felt to be most useful to policy makers as they attempted to define the scope and direction of a national program for controlling toxic air pollutants. The following paper is based on a draft staff report on the study released for review in September 1984. The report has not been formally released by the U.S. EPA; a final report is due by late spring of 1985. 相似文献