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331.
Francis Xavier Dery Tuokuu Uwafiokun Idemudia Eugene B. G Bawelle John Bosco Baguri Sumani 《Natural resources forum》2020,44(1):52-65
The fact that the artisanal and small-scale mining (ASM) sector in Ghana is driven largely by poverty means that the sector is a major source of livelihood for people in mining communities across the country. However, given the various social and environmental problems associated with the ASM sector, there is now an emerging consensus that the formalization of the sector would not only allow for these associated problems to be addressed but also ensures that the sector contributes to sustainable development and safeguard the livelihood of local communities. While a large body of extant literature has examined the challenges and opportunities facing the process of formalization, the question of the criminalization of the sector and its consequences for local livelihood has received only limited attention. Drawing from primary data collected during fieldwork in Ghana, this study examined the livelihood implications of the ban on galamsey in the Tarkwa-Nsuaem Municipality in South-Western Ghana from the perspectives of local communities and other key stakeholders. The study reveals that the ban on galamsey has imposed significant socio-economic hardships on the people and appears to be entrenching poverty rather than sustainable development. The study considers the theoretical and practical implications of the findings for sustainable livelihood enhancement in developing countries. 相似文献
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Norman L. Miller Larry L. Dale Charles F. Brush Sebastian D. Vicuna Tariq N. Kadir Emin C. Dogrul Francis I. Chung 《Journal of the American Water Resources Association》2009,45(4):857-866
Abstract: A series of drought simulations were performed for the California Central Valley using computer applications developed by the California Department of Water Resources and historical datasets representing a range of droughts from mild to severe for time periods lasting up to 60 years. Land use, agricultural cropping patterns, and water demand were held fixed at the 2003 level and water supply was decreased by amounts ranging between 25 and 50%, representing light to severe drought types. Impacts were examined for four hydrologic subbasins, the Sacramento Basin, the San Joaquin Basin, the Tulare Basin, and the Eastside Drainage. Results suggest the greatest impacts are in the San Joaquin and Tulare Basins, regions that are heavily irrigated and are presently overdrafted in most years. Regional surface water diversions decrease by as much as 70%. Stream‐to‐aquifer flows and aquifer storage declines were proportional to drought severity. Most significant was the decline in ground water head for the severe drought cases, where results suggest that under these scenarios the water table is unlikely to recover within the 30‐year model‐simulated future. However, the overall response to such droughts is not as severe as anticipated and the Sacramento Basin may act as ground‐water insurance to sustain California during extended dry periods. 相似文献
335.
Benjamin P. Oldroyd Luke A. Halling Gregory Good Wandee Wattanachaiyingcharoen Andrew B. Barron Piyamas Nanork Siriwat Wongsiri Francis L. Ratnieks 《Behavioral ecology and sociobiology》2001,50(4):371-377
Workers of the Asian hive bee, Apis cerana, are shown to have relatively high rates of worker ovary activation. In colonies with an active queen and brood nest, 1-5% of workers have eggs in their ovarioles. When A. cerana colonies are dequeened, workers rapidly activate their ovaries. After 4 days 15% have activated ovaries and after 6 days, 40%. A cerana police worker-laid eggs in the same way that A. florea and A. mellifera do, but are perhaps slightly more tolerant of worker-laid eggs than the other species. Nevertheless, no worker's sons were detected in a sample of 652 pupal males sampled from 4 queenright colonies. A cerana continue to police worker-laid eggs, even after worker oviposition has commenced in a queenless colony. 相似文献
336.
Abstract: The controversy ( Berger 1990, 1999 ; Wehausen 1999 ) over rapid extinction in bighorn sheep ( Ovis canadensis ) has focused on population size alone as a correlate to persistence time. We report on the persistence and population performance of 24 translocated populations of bighorn sheep. Persistence in these sheep was strongly correlated with larger patch sizes, greater distance to domestic sheep, higher population growth rates, and migratory movements, as well as to larger population sizes. Persistence was also positively correlated with larger average home-range size ( p = 0.058, n = 10 translocated populations) and home-range size of rams ( p = 0.087, n = 8 translocated populations). Greater home-range size and dispersal rates of bighorn sheep were positively correlated to larger patches. We conclude that patch size and thus habitat carrying capacity, not population size per se, is the primary correlate to both population performance and persistence. Because habitat carrying capacity defines the upper limit to population size, clearly the amount of suitable habitat in a patch is ultimately linked to population size. Larger populations (250+ animals) were more likely to recover rapidly to their pre-epizootic survey number following an epizootic ( p = 0.019), although the proportion of the population dying in the epizootic also influenced the probability of recovery ( p = 0.001). Expensive management efforts to restore or increase bighorn sheep populations should focus on large habitat patches located ≥23 km from domestic sheep, and less effort should be expended on populations in isolated, small patches of habitat. 相似文献
337.
Inorganic polyphosphates (PolyP) are simple linear phosphate (PO(4)(3-)) polymers which are produced by a variety of microorganisms. One of their functions is to complex metals resulting in their precipitation. We investigated the interaction of phosphate and low-molecular-weight PolyP (1400-1900Da) with uranyl ion at various pHs. Potentiometric titration of uranyl ion in the presence of phosphate showed two sharp inflection points at pHs 4 and 8 due to uranium hydrolysis reaction and interaction with phosphate. Titration of uranyl ion and PolyP revealed a broad inflection point starting at pH 4 indicating that complexation of U-PolyP occurs over a wide range of pHs with no uranium hydrolysis. EXAFS analysis of the U-HPO(4) complex revealed that an insoluble uranyl phosphate species was formed below pH 6; at higher pH (> or = 8) uranium formed a precipitate consisting of hydroxophosphato species. In contrast, adding uranyl ion to PolyP resulted in formation of U-PolyP complex over the entire pH range studied. At low pH (< or = 6) an insoluble U-PolyP complex having a monodentate coordination of phosphate with uranium was observed. Above pH 6 however, a soluble bidentate complex with phosphate and uranium was predominant. These results show that the complexation and solubility of uranium with PO(4) and PolyP are dependent upon pH. 相似文献
338.
Sarot Emeline Carillo-Baraglioli Marie-Françoise Duranthon Francis Péquignot Amandine Pyronnet Stéphane 《Environmental science and pollution research international》2017,24(20):16985-16993
Environmental Science and Pollution Research - One essential step of museum and clinical specimen preservation is immersion in a fixative fluid to prevent degradation. Formalin is the most largely... 相似文献
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Jolien Schure Verina Ingram Julius Chupezi Tieguhong Cleto Ndikumagenge 《Resources Policy》2011,36(4):363-371
This paper examines the institutional framework of artisanal mining in the forests of the Sangha Tri-National Landscape (TNS) in the Congo Basin. Artisanal miners in Cameroon and the Central African Republic (CAR) commonly make sacrifices to their god of diamonds, to improve fortunes. This study looks into ‘the other forces’; institutions that play a role in shaping the sector and its outcomes. These institutions comprise formal and informal institutions at a local, national, regional and international level. Although artisanal miners in TNS benefit by gaining cash income, this activity also carries risks as income is highly disparate and environmental impacts in this priority forest conservation area are expected to increase due to the growing competition over land use. It was concluded from a literature review, interviews and site visits that informal arrangements dominate the sector, especially in Cameroon, leading to poor relations between officials and miners and meaning that miners have few rights and no voice. The current institutional setup is inadequate to deal with current and anticipated social and environmental issues. Future interventions need to take into account the existing (local) types of organization, vulnerable groups, the interests of multiple actors and the fact that most miners are experienced but combine mining with other activities, such as agriculture, fishing and harvesting forest products. African initiatives concerning ASM offer opportunities to Cameroon and CAR to collaborate with other countries to combat similar issues. A regional integrated approach of both the forest and mining sector would be especially relevant for trans-boundary agreements, such as concerning the TNS, to reinforce positive outcomes for the landscape and the area's population. 相似文献