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Across West and Central Africa, wildlife provides a source of food and income. We investigated the relation between bushmeat hunting and household wealth and protein consumption in 2 rural communities in Bioko Island, Equatorial Guinea. One village was dedicated to commercial hunting, the other trapped game primarily for food. We tested whether commercial‐hunter households were nutritionally advantaged over subsistence‐hunter households due to their higher income from the bushmeat trade and greater access to wild‐animal protein. We conducted bushmeat‐offtake surveys in both villages (captures by hunters and carcasses arriving to each village). Mammals (including threatened primates: black colobus [Colobus satanas], Preussi's guenon [Allochrocebus preussi], and russet‐eared guenon [Cercopithecus erythrotis]), birds, and reptiles were hunted. The blue duiker (Philantomba monticola), giant pouched rat (Cricetomys emini), and brush‐tailed porcupine (Atherurus africanus) contributed almost all the animal biomass hunted, consumed, or sold in both villages. Monkeys and Ogilbyi's duikers (Cephalophus ogilbyi) were hunted only by commercial hunters. Commercial hunters generated a mean of US$2000/year from bushmeat sales. Households with commercial hunters were on average wealthier, generated more income, spent more money on nonessential goods, and bought more products they did not grow. By contrast, households with subsistence hunters spent less on market items, spent more on essential products, and grew more of their own food. Despite these differences, average consumption of vegetable protein and domestic meat and bushmeat protein did not differ between villages. Our results highlight the importance of understanding the socioeconomic and nutritional context of commercial and subsistence bushmeat hunting to correctly interpret ways of reducing their effects on threatened species and to enable the sustainable offtake of more productive taxa. Contrastes en el Sustento y la Ingesta de Proteínas entre Carne de Caza de Subsistencia y Comercial en Dos Aldeas en Isla Bioko, Guinea Ecuatorial 相似文献
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Hendrik Weber Julian Bock Jens Klimke Christian Roesener Johannes Hiller Robert Krajewski 《Traffic injury prevention》2019,20(4):S65-S70
AbstractObjective: In order to introduce automated vehicles on public roads, it is necessary to ensure that these vehicles are safe to operate in traffic. One challenge is to prove that all physically possible variations of situations can be handled safely within the operational design domain of the vehicle. A promising approach to handling the set of possible situations is to identify a manageable number of logical scenarios, which provide an abstraction for object properties and behavior within the situations. These can then be transferred into concrete scenarios defining all parameters necessary to reproduce the situation in different test environments.Methods: This article proposes a framework for defining safety-relevant scenarios based on the potential collision between the subject vehicle and a challenging object, which forces the subject vehicle to depart from its planned course of action to avoid a collision. This allows defining only safety-relevant scenarios, which can directly be related to accident classification. The first criterion for defining a scenario is the area of the subject vehicle with which the object would collide. As a second criterion, 8 different positions around the subject vehicle are considered. To account for other relevant objects in the scenario, factors that influence the challenge for the subject vehicle can be added to the scenario. These are grouped as action constraints, dynamic occlusions, and causal chains.Results: By applying the proposed systematics, a catalog of base scenarios for a vehicle traveling on controlled-access highways has been generated, which can directly be linked to parameters in accident classification. The catalog serves as a basis for scenario classification within the PEGASUS project.Conclusions: Defining a limited number of safety-relevant scenarios helps to realize a systematic safety assurance process for automated vehicles. Scenarios are defined based on the point of the potential collision of a challenging object with the subject vehicle and its initial position. This approach allows defining scenarios for different environments and different driving states of the subject vehicle using the same mechanisms. A next step is the generation of logical scenarios for other driving states of the subject vehicle and for other traffic environments. 相似文献
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Debra F. Pflughoeft-Hassett David J. Hassett Kurt E. Eylands Greg F. Weber Cameron E. Martin 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1214-1218
The duct injection retrofit process for flue gas cleanup of sulfur dioxide emissions has been demonstrated at several sites in the United States through a series of U.S. Department of Energy research projects. As a subcontractor on one of the projects, the University of North Dakota Energy & Environmental Research Center performed a comprehensive characterization of four residues from three demonstration sites. The characterization task objective was to facilitate understanding of materials handling and to identify potential disposal and utilization options for these high-volume coal utilization solid residues. Characterization included evaluation of the physical and engineering properties, chemical composition, mineralogy, and leaching potential. Chemical characterization results provided interesting and valuable information from the standpoint of the bulk chemistry and phase assemblages, as well as potential environmental issues associated with the use or disposal of these materials. Results of the chemical and mineralogical characterizations indicate that duct injection residues will be suitable for specific utilization applications and that disposal of these residues should be similar to many conventional coal combustion residues. Significant mineralogical phase changes were noted in long-term leaching experiments. 相似文献
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Rainer Götz Volker Sokollek Roland Weber 《Environmental science and pollution research international》2013,20(4):1925-1936
α-HCH, β-HCH, and γ-HCH (lindane) were listed as persistent organic pollutants in the Stockholm Convention. Therefore, they need to be globally addressed including the wastes remaining from historic use and production. While at most lindane production sites the unintentionally produced 85 % HCH waste isomers have been deposited, at a former pesticide factory in Hamburg-Moorfleet HCH waste isomers have been recycled from 1953 to 1984 by thermal decomposition to chlorobenzenes and resulted in high polychlorinated dibenzo-p-dioxin/polychlorinated dibenzofuran (PCDD/PCDF)-contaminated residues. The management of the PCDD/PCDF-contaminated waste from the former pesticide factory in Hamburg has been assessed and quantified. Based on past accredited PCDD/PCDF measurements, the registered 3,700 tonnes of disposed thermal HCH decomposition residue contained 333 to 854 kg of PCDD/PCDF toxicity equivalent (I-TEQ) in 53–102 tonnes total sum of PCDD/PCDF. The wastes have been deposited together with other wastes in landfills in Hamburg and other parts of Germany. For the Georgswerder landfill (Hamburg), where approximately 50 % of the PCDD/PCDF is disposed, current and previous situation and remediation activities are described. While PCDD/PCDF leaching from the landfill is controlled and incinerated, more water soluble organochlorines (vinyl chloride, cis-1,2-dichlorethene, chlorobenzenes) and benzene remain as a challenge for groundwater management. A comprehensive aftercare program has been established and will need to be operated by future generations including renewal of containment systems. Former lindane/HCH productions need—in addition to HCH deposits—to be assessed for possible recycling practice of HCH and related PCDD/PCDF-containing deposits. This could systematically be addressed within the Stockholm Convention implementation. 相似文献
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Wiszniowski J Surmacz-Górska J Robert D Weber JV 《Journal of environmental management》2007,85(1):59-68
A pre-denitrification activated sludge system (AS) without internal recycle was used in lab-scale studies of landfill leachate treatment. A bentonite supplement at a ratio of 1:4 (mineral : biomass) was used to ensure high sludge settling levels and to serve as a micro-organisms carrier. The system was operated within different parameters such as hydraulic retention time (HRT), ammonia loading rate (ALR) or external recycle ratio, which was adapted to treat varying leachate concentrations of COD and ammonia, ranging from 1020 to 2680 mgO(2)l(-1) and 400-890 mgNH(4)-Nl(-1) respectively. The nitrification was complete and ammonia oxidation reached 99%; this was obtained while the ALR did not exceed 0.09 g NH(4)(+)-Ng(-1)MLVSS d(-1) and HRT was not lower than 1 day (in the aeration reactor). The performance of denitrification was successfully improved by controlling the external recycle rate, when the BOD(5)/N ratio in the raw leachate was 4.1. Consequently, N-removal of up to 80% was achieved. A 10-fold decrease in the denitrification rate was obtained at a BOD(5)/N ratio of 0.5. The efficiency of COD removal varied significantly from 36% to 84%. The positive effect of bentonite addition was determined and is discussed based on preliminary studies. The experiments were carried out in fill-and-draw activated sludge with bentonite; the biomass ratio was 1:2. The activated sludge with bentonite was fed with a synthetic high ammonia and organic-free medium. 相似文献