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191.
Climate change poses a major threat to human security and poverty in Africa. In Africa, where livelihoods are mainly based on climate-dependent resources and environment, the effect of climate change will be disproportionate and severe. Moreover, Africa's capacity to adapt to and cope with the adverse effects of climate variability is generally weak. This article discusses how climate change affects human security in Africa. It also assesses the policy options available to policymakers in terms of mitigation and adaptation to climate change to reduce vulnerability and human insecurity in Africa.  相似文献   
192.
In South Africa, extreme rural poverty often geographically overlaps with areas of high and important biodiversity. Attempts to bring about land-based poverty reduction projects in such areas tends to trigger tensions among stakeholders purporting to be concerned about local people’s welfare, as well as the environment. Using discursive document analysis and semi-structured interviews, the paper discusses a case study of the Wild Coast, an area celebrated for its high biodiversity and ‘beauty’, which reveals that a tension among environmental non-government organisations, government agencies and the private sector, on the best development option, exacerbates the threats to local livelihood options and biodiversity conservation.  相似文献   
193.
Persistent organic pollutants such as Polychlorinated biphenyls (PCB) and dichloro diphenyl trichloroethane (DDT) are known to exert various adverse health effects in wildlife mammals. The impact from dietary intake of minke whale (Balaenoptera acutorostrata) blubber high in organohalogen and other chemical contaminants on renal morphology and function was investigated via a controlled study on West Greenland sledge dogs (Canis familiaris). Our results showed significantly higher frequencies of glomerular, tubular, and interstitial lesions in the exposed group. Furthermore, higher urine protein?:?creatinine ratio and plasma urea levels were found in the exposed group, which indicated a negative impact on kidney function via tubular and glomerular dysfunctions. The lesions were similar to those observed in top predator marine species–such as seals and polar bears–and humans exposed via diet to persistent environmental pollutants. The lesions may have impacts on the overall health of these animals. It is reasonable to suggest that chronic exposure to organic pollutants via a country diet of high trophic level marine organisms may have an impact on renal morphology and function in Arctic apex predators in general as well as Inuit people.  相似文献   
194.
The presence of organochlorine compounds (OC) such as DDT and their metabolites in the environment have created a significant environmental concern over the years due to adverse effects. Consequently, DDT has been banned in many countries. However, it is still used in some countries including South Africa, particularly for vector-borne disease eradication programmes. Since the presence of DDT and its metabolites may provide an indication of the general exposure and use of these compounds, there was a need for such a study. Human breast milk samples (n = 30) were collected from mothers within the age range of 19–40 years from the Thohoyandou area, South Africa. The liquid–liquid extraction method was used to extract DDT and its metabolites from the samples. The crude extracts were subjected to column chromatography for measurements of OC levels. The concentration ranges of the contaminants were as follows: not detected (ND) to1770 ng g?1 (2,4′-DDE); ND to 3977 ng g?1 (4,4′-DDE); ND to 3250 ng g?1 (2,4′-DDD); ND to 2580 ng g?1 (4,4′-DDD) and ND to 2847 ng g?1 (4,4′-DDT). The mean ΣDDE, ΣDDD and ΣDDT obtained from the villages were 1180 ng g?1, 830 ng g?1 and 690 ng g?1, respectively. The total DDT ranged from 820–7473 ng g?1. The estimated daily intake varied from 260 to 4696 ng g?1, ND-10551 ng g?1 and ND-4237 ng g?1 for DDE, DDD and DDT, respectively. These values are significantly higher than the FAO/WHO acceptable daily intake (ADI) of 20 ng g?1. The ΣDDT was found to decrease with increasing age of the mothers. The observed high levels of DDE compared to DDT indicated chronic exposure of the mothers to DDT, which is metabolized to DDE and retained in the body.  相似文献   
195.
朱磊  李怀恩  李家科 《环境科学学报》2012,32(10):2617-2624
通过建立渭河关中段水质水量响应关系程序,对渭河关中段规划水平年(2020年)不同来水频率(P)条件下丰水期、平水期、枯水期的水质水量响应关系进行定量化分析研究.结果表明,规划水平年丰水期、平水期、枯水期同一断面在不同来水频率下COD和NH+4-N从小到大的排序均为:P=25%、P=50%、P=75%、P=95%.规划水平年丰水期、平水期、枯水期的COD在林家村断面至兴平断面较小,低于地表水环境质量标准(GB3838—2002)Ⅴ类水标准,而后逐渐开始升高,南营断面COD涨幅较大,至咸阳断面升至最高,后又逐渐减低;规划水平年丰水期、平水期、枯水期的NH+4-N在林家村断面至兴平断面较小,低于地表水环境质量标准Ⅴ类水标准,而后逐渐开始升高,咸阳断面NH+4-N增幅较大,至树园断面升至最高.  相似文献   
196.
The Paris Agreement?s nationally determined contributions (NDCs) provide an excellent point of entry to simultaneously address climate change and the 2030 Agenda for Sustainable Development and its Sustainable Development Goals (SDGs). This study sets out to explore the connections between climate action plans (NDCs) and each of the 17 Sustainable Development Goals (SDGs). In this study, we used four levels of visibility, that is, present, generic, implied and absent to provide a broad perspective of the extent to which South Africa?s NDC is aligned with the targets of the SDGs. Our results revealed that South Africa?s NDC has 12% present level of visibility to the SDG targets, with SDG 7 Affordable and Clean Energy and SDG 13 Climate Action showing the highest representation of present level of visibility. By contrast, the absent level of visibility NDC showed 53% in the SDG targets, with SDG 5 Gender Equity, SDG 16 Peace, Justice and Strong Institutions and SDG 3 Good Health and Well‐Being, showing the highest representation of absent level of visibility. These results indicate that there is scope to improve the alignment of South Africa?s NDCs with the SDG targets. To this end, we have identified areas that may benefit with further elaboration in the country?s second NDC.  相似文献   
197.
This paper explores a fruitful convergence between the distributive and procedural dimensions of environmental justice theory and current debates in the field of development studies over capitals and capabilities, institutions, and discourse formation to shed new light on natural resource management projects in the developing world. Specifically, we document the planning and implementation of two types of water interventions in two contrasting regions: watershed development programmes in northeast India and small reservoirs in sub‐Saharan West Africa. We find that there is a contradiction between the inherently political nature of water interventions and the fact that such projects remain grounded in apolitical, technical and managerial narratives. In contrast to the new semantic of development, this depoliticization results in the near absence of attention paid to procedural (participation and empowerment) and distributive (equity) justice concerns and in local actors having to revert to covert ways to achieve their ends. A constructive dialogue between development studies and environmental justice scholars can offer a fresh look on the society‐environment nexus in the developing world.  相似文献   
198.
Faced with the prospects of a changing climate, a small but increasing number of countries are developing legal and regulatory frameworks that explicitly address climate change. Moreover at least some of these laws and policies carve out substantial roles for local governments. The present paper surveys three countries from different regions in the Global South that have developed or are developing such laws and policies: the Philippines (Asia-Pacific), Mexico and more specifically its State of Chiapas (Latin America), and South Africa (Africa). It examines those experiences through two different lenses. The paper first reviews the steps by which those laws or policies were developed. For this review, criteria for effective consultative processes are proposed. The study then examines the three climate change laws or policies per se. To this end, a framework including four modes of multi-level urban climate governance (governing by regulation, governing through enabling, governing by provision, governing with representation and consultation) is utilised. The paper ends with synthetic conclusions as to which experiences represent promising practices, and what other lessons are relevant for countries embarking on such processes.  相似文献   
199.
Bridging the water infrastructure gap has become a major policy concern. In rural areas of Africa, access to water is as much constrained by territorial coverage as it is by the poor conditions of water points due to the difficulty in mobilizing communities for repairs. This paper examines the equity considerations of a rural water and sanitation programme in a district of Mozambique, and their impacts on the achievement of the programme's objectives. Our analysis underlines the contradictions in the conceptualization of equity in the design, planning and implementation of the programme. Even an explicitly pro‐poor strategy can fall short of delivering equity. Our findings stress the fact that overlooking local perception of equity can have a direct impact on the ability of a community to ensure the maintenance of their water points. They call for a careful definition of equity in the design of water programmes, as well as closer attention to this criterion as a precondition to achieving the long‐term objective of the programme.  相似文献   
200.
西笤溪流域重金属污染磁学研究及多元分析   总被引:10,自引:0,他引:10  
对西苕溪流域的土壤样品及部分太湖近岸表层底泥样品,进行了环境磁学测试与化学分析.采用指标聚类分析,抽取磁化率、S比值和Cr、Fe、Pb、Sr、Ti、Zn含量等8个典型指标.再应用模糊C均值聚类分析,分辨出了4种不同的样品类型和两种不同的人类活动响应.取自丘陵山地的第一类样品,以强的磁化率、高的S比值和低的Sr、Ni和Zn含量为特征,代表了流域的自然背景.分布在河谷平原农耕区的第二类样品,磁化率、S比值以及重金属含量都很低,反映了农业活动对环境的影响.而分布在滨湖平原和东苕溪流域的第三类样品,Sr、Ni和Zn含量最高,反映了工业活动对环境的影响.代表丘陵与平原过渡带的第四类样品,其磁参数和重金属含量介于丘陵山地与平原之间.由于流域的磁背景场很高,且人类活动多元化,磁与重金属的相关性差,因此单一的磁化率不能直接指示污染状况.  相似文献   
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