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1.
Sub-Saharan Africa is by far and away the most disadvantaged of the world's three main developing regions. Worse, its situation has mostly been deteriorating for much of the past several decades. Its agriculture is severely under-productive, and per capita food supplies have been steadily dwindling. Its environments and natural-resource base, characterised by water deficits, soil erosion, fuelwood shortages, rudimentary agro-practices, and grossly inadequate infrastructure, are generally unfavourable for sustainable agriculture. The population has expanded until it far exceeds carrying capacity, yet its growth rate is the highest in the world. The region also suffers from more disease than any other region. There is widespread and deepening poverty. As a result of these and other problems, and despite major food imports, two-thirds of the people are malnourished, one-quarter of whom endure outright hunger, even semi-starvation. Both these proportions appear set to keep on increasing both relatively and absolutely. Were these problems to persist with their decades-long trends, there could eventually arrive a stage when much larger numbers of people would succumb to terminal malnutrition, precipitating a human tragedy of unprecedented proportions. Fortunately, success stories demonstrate that solutions are available, on the part of both governments concerned and international agencies. Because of ignorance, or rather ignore-ance of the potential mortality disaster ahead, however, not nearly enough has been done to address the challenge with the energy and urgency to match its scale.  相似文献   

2.
Abstract

This paper critically examines how privatisation and liberalisation of electricity provision is reconstructing energy consumption practices. The paper discusses the commercial restructuring of the electricity industry in the UK over the last four years, illustrating how a reconfiguration of production and consumption interests is transforming the utility marketplace: differentiating the value of resource units, distinguishing between infrastructure suppliers and stratifying utility customers. This process is shown to be resulting in differential forms of service provision as utility companies actively engage with more lucrative customers, presenting opportunities for environmental innovation, while disengaging from unprofitable customers and heightening social polarisation.  相似文献   

3.
Sexual violence is an epidemic that often overlaps with the AIDS pandemic and is often a cause and consequence of the spread of HIV/AIDS amongst women and girls. Presently, half or more of the 40 million people infected with HIV in the world are women. Millions of those infected are aged 15-24 years and have suffered some form of intimate partner violence. This group accounts for half of all new infections. In sub-Saharan Africa, young women account for 75% of HIV infections and are approximately two-and-a-half times more likely to be infected than young men of the same age (UNAIDS, Report on the Global AIDS Epidemic: 4th Global Report, Geneva, 2004). What makes women, especially girls and younger women, so disproportionately vulnerable to HIV infection, and why have current AIDS control efforts in sub-Saharan Africa largely failed to stem the epidemic in this gender?  相似文献   

4.
Securing sustainable livelihood conditions and reducing the risk of outmigration in savanna ecosystems hosted in the tropical semiarid regions is of fundamental importance for the future of humanity in general. Although precipitation in tropical drylands, or savannas, is generally more significant than one might expect, these regions are subject to considerable rainfall variability which causes frequent periods of water deficiency. This paper addresses the twin problems of “drought and desertification” from a water perspective, focusing on the soil moisture (green water) and plant water uptake deficiencies. It makes a clear distinction between long‐term climate change, meteorological drought, and agricultural droughts and dry spells caused by rainfall variability and land degradation. It then formulates recommendations to better cope with and to build resilience to droughts and dry spells. Coping with desertification requires a new conceptual framework based on green‐blue water resources to identify hydrological opportunities in a sea of constraints. This paper proposes an integrated land/water approach to desertification where ecosystem management supports agricultural development to build social‐ecological resilience to droughts and dry spells. This approach is based on the premise that to combat desertification, focus should shift from reducing trends of land degradation in agricultural systems to water resource management in savannas and to landscape‐wide ecosystem management.  相似文献   

5.
In this paper, we argue for the importance of incorporating a gendered perspective for the effective development of sustainable agricultural biotechnology systems in sub-Saharan Africa. Priority setting for agricultural policy and project development requires attention to gender issues specific to the demands of agricultural biotechnology. This is essential for successfully addressing food security and poverty reduction in sub-Saharan Africa (SSA). There has been a great deal of debate and literature on the implications of gender in agricultural development and policy. However, the implications of gender in agricultural biotechnology and have received relatively less attention, especially in SSA. Based on interviews with key stakeholders in agricultural biotechnology across SSA, review of pertinent literature and field observations, we have found that incorporating a gendered perspective is critical for the sustainable development of agricultural biotechnology and requires attention in five areas: the inclusion of women, particularly women farmers, in decision-making around biotech/genetically modified (GM) crop and trait selection; equal representation of women as men in education for agricultural science and in agricultural biotechnology research and development professions; greater involvement of women in extension services and farmers’ associations for successful delivery of information about biotech crops equality between men and women in access to resources for biotech/GM crop cultivation; and increased control for women farmers over biotech/GM crop management and income generation. We explain the consequences of failing to include such gender-responsive considerations into priority setting for agricultural biotechnology development and policy in SSA and provide recommendations for how policy makers and project partners of development initiatives can avoid such oversights.  相似文献   

6.
Despite the reported benefits of conservation agriculture (CA), its wider up-scaling in Sub-Saharan Africa (SSA) has remained fairly limited. This paper shows how a newly developed qualitative expert assessment approach for CA adoption (QAToCA) was applied to determine its adoption potential in SSA. CA adoption potential is not a predictor of observed adoption rates. Instead, our aim was to systematically check relevant factors that may be influencing its adoption. QAToCA delivers an assessment of how suitable conditions “and thus the likelihood for CA adoption” are. Results show that the high CA adoption potentials exhibited by the Malawi and Zambia case relate mostly to positive institutional factors. On the other hand, the low adoption potential of the Zimbabwe case, in spite of observed higher estimates, is attributed mainly to unstable and less secured market conditions for CA. In the case of Southern Burkina Faso, the potential for CA adoption is determined to be high, and this assessment deviates from lower observed figures. This is attributed mainly to strong competition of CA and livestock for residues in this region. Lastly, the high adoption potential found in Northern Burkina Faso is explained mainly by the fact that farmers here have no alternative other than to adopt the locally adapted CA system—Zaï farming. Results of this assessment should help promoters of CA in the given regions to reflect on their activities and to eventually adjust or redesign them based on a more explicit understanding of where problems and opportunities are found.  相似文献   

7.
This paper contributes to the debate on governance, transparency and Corporate Social Responsibility (CSR) in oil-rich sub-Saharan Africa, focusing on the case of Chad. Over the past decade, Chad has gained international standing as an oil-producer on the back of the World Bank-catalyzed Chad–Cameroon pipeline project, which aims to develop the country's oil-rich Doba region. The analysis begins by examining at greater length the challenges to implementing a CSR agenda in fragile states such as Chad, highlighting, specifically, the barriers to facilitating development in environments exhibiting Dutch Disease-like symptoms. It subsequently critiques CSR programs in resource-rich developing countries, questioning the role of corporate intervention in such settings. The paper concludes by examining how CSR has been “operationalized” in Chad itself, where to ensure that the finances generated from the oil project are properly managed, the Bank instituted a comprehensive revenue management plan.  相似文献   

8.
9.
A shallow-depth ground water area was investigated to identify the dominant processes governing the distribution of hydrocarbon contaminants and hydrogeochemical parameters. The ground water in the study site has been highly contaminated with petroleum hydrocarbons. A preliminary pump-and-treatment remediation technology was applied for 4 yr at the site. Multivariate analyses were applied to hydrogeochemical data obtained before and after the rainy season. The pump-and-treatment application, indigenous biodegradation, and mixing by precipitation recharge are the major factors or events involved in the distribution of geochemical parameters of the ground water in the study area. Site-specific artificial pavement also played an important role in the evolution of the ground water chemistry. A conventional graphical analysis method (Piper plot) of major ions did not effectively reveal these effects. In this study, we demonstrate the usefulness of multivariate analysis (factor and cluster analyses) using biodegradation indicator parameters, as well as major cations and anions, for the study of the ground water system in the hydrocarbon-contaminated site.  相似文献   

10.
11.
Lead levels in different environmental media (soil, grass leaves, water, ceramics, pencil, paint, crayons and cosmetics) were determined to assess the major sources of lead exposure in Thohoyandou, South Africa. Soil and plant leaves were used as indicators of Pb pollution from vehicle exhaust emissions. After digestion with concentrated acids (HNO3, HCl and HClO4) Pb concentrations were determined in triplicate using a flame atomic absorption spectrometer. The mean Pb concentrations at the kerb of selected busy roads were 205.5 ± 90, 273.0 ± 90 and 312.8 ± 81 μg g−1 and 154.7 ± 67, 182.9 ± 76 and 240.6 ± 66 μg g−1 for soil and plant leaves (dry weight) respectively. These concentrations were substantially higher than the values found on soils 50 m away from the roads (97.4 ± 11 μg g−1). Pb concentrations in plants collected further away from the road (50 m) were substantially lower (71.8 ± 9.0 μg g−1). The observed levels on soil are lower than the UK critical value of 500 μg g−1 for gardens and allotments; and 2000 μg g−1 for parks and open space as well as the Canadian values for agricultural (375 μg g−1), residential (500 μg g−1 and industrial (1000 μg g−1). From these data it was clear that Pb concentrations in soil samples were substantially higher than the levels obtained for plant leaves. The Pb levels in green crayons, blue crayons, pencils (from China & Germany), were 10650 ± 75.2, 8200 ± 52.4, 1160 ± 50.2, 79 ± 10.1 μg g−1 for the inner contents; and 4870 ± 58.1, 5650 ± 55.5, 1950 ± 46.6, 60 ± 12.9 μg g−1 for the outer surface paint respectively. The ceramics showed Pb levels of 630 ± 50.3 μg g−1 (saucer) and 560 ± 32.2 μg g−1 (cup), while the inner contents and outer surface paint showed 480 ± 32.4 and 318 ± 21.2 μg g−1 of Pb respectively. Early morning tap water flush gave a Pb level of 20.6 ± 5.6 μg Pb l−1. This value is higher than the WHO and FDA maximum permissible concentrations of 10 μg l−1 and 15 μg l−1 respectively.  相似文献   

12.
13.
Two hundred and fifty-seven urine samples collected from school children living in the Manzini region, Swaziland, were analysed for lead (Pb), using a graphite furnace atomic absorption spectrometer. The mean urine lead concentration for the urban schools ranged from 0.038–0.040 gml–1, while that for the rural schools ranged from 0.017–0.022 gml–1. The observed range shown by the urban schools was above the normal (for healthy humans) urine lead concentration of 0.035 gml–1. However, the mean urine lead concentration for the rural schools was found to be lower than this value. The mean urine lead concentration for the urban schools was significantly higher than that of the rural schools. The differences in the mean urine lead concentrations for boys and girls from both urban and rural schools were found not to be significant, despite the higher values shown by the girls. The difference in lead concentrations between urban and rural schools in Manzini was thought to be due to the traffic density within the urban area.  相似文献   

14.
This study was performed to investigate mercury (Hg) tolerance, accumulation, and translocation within the genus Salix for the potential use of this plant to remediate Hg-contaminated sites. Six clones of willow (Salix spp.) were tested on tolerance to Hg by treating plants grown in solution culture with 0 to 15 microM HgCl(2). Results showed that willow had a large variation in its sensitivity to Hg. However, the accumulation and translocation of Hg to shoots was similar in the eight tested willow clones as shown by cold vapor atomic absorption spectrometry analysis when plants were treated with 0.5 microM HgCl(2) in a nutrient solution. The majority of total Hg accumulated was localized to the roots, whereas only 0.45 to 0.62% of the total Hg accumulated via roots was translocated to the shoots. Thus, the root system is the main tissue of willow that accumulates Hg and the majority of the Hg in the root system (80%) was bound in the cell wall.  相似文献   

15.
16.
Mining is an important part of the South African economy and has been the driver of much of the economic development of the country. However, the small–scale mining subsector still has to realise its full potential. A small–scale mine has been defined as a mining activity employing less than 50 people and with an annual turnover of less than 7.5 million Rand and includes artisanal mines. Small–scale miners are involved in many commodities but there appears to be a bias towards gold, diamonds and quarrying for construction materials, including brickclays. Small–scale mining is regulated by the same legislation (i.e., for the environment, labour, mineral rights, exploration and mining permitting, and skills development) as large–scale mining, though compliance is low, particularly where artisanal mining in concerned. The effective participation of small–scale miners in the mining sector is hampered by their lack of skills, i.e., technical, business and management, and their limited access to mineral deposits, capital and markets. Some of these hindrances have been inherited from the imbalances of the colonial and apartheid eras and continue to act as barriers, making entrance to the industry difficult. For those who have entered the industry out of desperation, as is the case with most artisanal miners, their activities result in negative impacts evident in the inefficient, unsafe and environmentally unfriendly operations. With the advent of the new political dispensation in South Africa, a new era is dawning for the country’s small–scale mining subsector. This has resulted in a change of attitude and new government policies which have led to special programmes being put in place to promote the subsector. Intervention strategies for the support of small–scale mining (some of which are already in operation) include programmes for kickstarting mineral beneficiation and value–addition projects, development of appropriate technologies and skills and technology transfer. Proponents of small–scale mining see a well–regulated industry as being the cornerstone of future rural economic development, particularly for previously disadvantaged communities in the poverty nodes.  相似文献   

17.
18.
Phytoremediation depends on the ability of plants to tolerate and assimilate contaminants. This research characterized the interaction between several ornamental plant species and the fungicidal active ingredient, metalaxyl [N-(2,6-dimethylphenyl)-N-(methoxyacetyl)alanine methyl ester]. Species evaluated included sweetflag (Acorus gramineus Sol. ex Aiton), canna (Canna hybrida L. 'Yellow King Humbert'), parrotfeather [Myriophyllum aquaticum (Vell.) Verdc.], and pickerelweed (Pontederia cordata L.). Metalaxyl tolerance levels for each species were determined by exposing plants for 7 d to solutions containing 0, 5, 10, 25, 50, 75, or 100 mg metalaxyl L-1 aqueous nutrient media. Response endpoints included fresh mass production after 7 d exposure and 7 d post-exposure and quantum efficiency using dark-adapted (Fv/Fm) and light-adapted (fluorescence yields) plants. Metalaxyl uptake and distribution within the plant was determined by growing plants in aqueous nutrient media containing 1.18 x 10(6) Bq L-1 [14C]metalaxyl (0.909 mg L-1) for 1, 3, 5, or 7 d. Plant tissues were combusted and analyzed by liquid scintillation counting. Metalaxyl had no effects on the endpoints measured, except for fresh mass production of sweetflag at the 75 and 100 mg L-1 treatment levels. However, leaf necrosis was apparent in most species after 5 d exposure to concentrations greater than 25 mg L-1. Metalaxyl removal from the spiked nutrient media ranged from 15 to 60% during the 7-d exposure period. The majority of metalaxyl removed from the solution was detected within individual plants. In nearly all cases, activity from the radiolabeled pesticide accumulated in the leaves. Uptake of metalaxyl was correlated with water uptake throughout the 7 d. These results suggest that all species examined may be good candidates for incorporation into a phytoremediation scheme for metalaxyl.  相似文献   

19.
20.
Managing disposal of water produced with petroleum in Kuwait   总被引:1,自引:0,他引:1  
Disposal of water produced with petroleum has been of great interest in Kuwait for the last 20 years. The current problem arose when the Burgan oil field, which is the second largest field in the world, experienced successive increases in the water content of the produced oil. This study introduces a decision-making analysis of the considered alternatives for the disposal of the produced water. Four alternative solutions exist for the industry as practical solutions for the disposal of water produced in Kuwait. The first method utilizes a large number of pits to discharge water. The second alternative depends on discharging water into sealed pits. The third approach to dispose water is by injecting the water underground. The last method is similar to the previous one, but takes into consideration the recovery of reservoir pressure to maintain the rate of oil production. A questionnaire was distributed to 48 experts at the top management level of the petroleum companies and the governmental authority. The data collected considered cost, efficiency, and environmental parameters. Based on the data, a statistical analysis was conducted using the factor analysis method to reduce the number of investigated variables. The analysis concluded that the optimal solution is to use the effluent injection method to discharge water produced with oil in Burgan and similar fields in Kuwait.  相似文献   

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