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111.
Integration of indigenous knowledge and ethnoscientific approaches into contemporary frameworks for conservation and sustainable management of natural resources will become increasingly important in policies on an international and national level, both in countries that are industrialised and those that have a developing status. We set the scene on how this can be done by exploring the key conditions and dimensions of a dialogue between ȁ8ontologiesȁ9 and the roles, which ethnosciences could play in this process. First, the roles of ethnosciences in the context of sustainable development were analysed, placing emphasis on the implications arising when western sciences aspire to relate to indigenous forms of␣knowledge. Secondly, the contributions of ethnosciences to such an ȁ8inter- ontological dialogueȁ9 were explored, based on an ethnoecological study of the encounter of sciences and indigenous knowledge in the Andes of Bolivia, and reviewed experiences from mangrove systems in Kenya, India and Sri Lanka, and from case-studies in other ecosystems world-wide, incl. Australia, Burkina Faso, Ecuador, Ethiopia, Guatemala, Indonesia, Nepal, Niger, Philippines, Senegal, South-Africa and Tanzania.  相似文献   
112.
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   
113.
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   
114.
This paper integrates tourism, economic growth, and environmental issues in a multivariate format. Unlike recent research on this topic, a panel data of selected sample nations of sub-Saharan Africa is adopted by using cointegration and panel regression models. The current research discovers both long-run equilibrium and short-run dynamics between economic growth, tourism, energy use, and carbon emissions in sub-Saharan Africa. Furthermore, tourism and energy use show a highly significant direct impact on economic growth. In addition, tourism, energy use, and economic growth yield a highly significant positive effect on carbon emissions. Dissecting the region into oil producers and non-oil producers further suggests that the economic growth of sub-Saharan Africa has been accomplished by strong growth in tourism and energy use. However, there is highly significant evidence that in oil producing countries, CO2 emissions are directly affected by energy use and economic growth and not by tourism. For non-oil producing countries, tourism and energy use but not economic growth incur a highly significant positive impact on carbon emissions.  相似文献   
115.
This study demonstrates that countries responded quite differently to calls for healthcare workers (HCWs) during the Ebola epidemic in West Africa in 2014. Using a new dataset on the scale and timing of national pledges and the deployment of HCWs to states experiencing outbreaks of the virus disease (principally, Guinea, Liberia, and Sierra Leone), it shows that few foreign nations deployed HCWs early, some made pledges but then fulfilled them slowly, and most sent no HCWs at all. To aid understanding of such national responses, the paper reviews five theoretical perspectives that offer potentially competing or complementary explanations of foreign government medical assistance for international public health emergencies. The study systematically validates that countries varied greatly in whether and when they addressed HCW deployment needs during the Ebola crisis of 2014, and offers suggestions for a theory‐driven inquiry to elucidate the logics of foreign interventions in critical infectious disease epidemics.  相似文献   
116.
Illegal, unregulated, and unreported (IUU) fishing poses a major threat to effective management of marine resources, affecting biodiversity and communities dependent on these coastal resources. Spatiotemporal patterns of industrial fisheries in developing countries are often poorly understood, and global efforts to describe spatial patterns of fishing vessel activity are currently based on automatic identification system (AIS) data. However, AIS is often not a legal requirement on fishing vessels, likely resulting in underestimates of the scale and distribution of legal and illegal fishing activity, which could have significant ramifications for targeted enforcement efforts and the management of fisheries resources. To help address this knowledge gap, we analyzed 3 years of vessel monitoring system (VMS) data in partnership with the national fisheries department in the Republic of the Congo to describe the behavior of national and distant-water industrial fleets operating in these waters. We found that the spatial footprint of the industrial fisheries fleet encompassed over one-quarter of the Exclusive Economic Zone. On average, 73% of fishing activity took place on the continental shelf (waters shallower than 200 m). Our findings highlight that VMS is not acting as a deterrent or being effectively used as a proactive management tool. As much as 33% (13% on average) of fishing effort occurred in prohibited areas set aside to protect biodiversity, including artisanal fisheries resources, and the distant-water fleet responsible for as much as 84% of this illegal activity. Given the growth in industrial and distant-water fleets across the region, as well as low levels of management and enforcement, these findings highlight that there is an urgent need for the global community to help strengthen regional and national capacity to analyze national scale data sets if efforts to combat IUU fishing are to be effective.  相似文献   
117.
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   
118.
To support grazing and fire management of communal semi-arid to sub-humid African rangelands, the assessment of grazing capacity is illustrated for cattle. The forage dry matter intake (DMI) was divided into four components: 1) the mature standing crop, 2) the green part of the standing crop, 3) the regrowth after range fires, and 4) browse. The relationship between the potential DMI and the crude protein (CP) concentration of the forage was modelled. The DMI ranged from 5 to 50% for forage with low to high CP concentrations, respectively. The DMI of browse was fixed at 0 and 10% of the DMI of unburnt vegetation for plain and woodland systems, respectively. The potential DMI of the four forage components combined, based on data of the early- to mid-dry season, was matched with livestock requirements to calculate grazing capacities. Possible combinations of and changes in the forage components, representing grazing capacities for different seasons of the year, were calculated and visualised. Lastly, it was demonstrated how to assess the proportion of the rangeland that should be burnt to make optimal use of the low quality forage available in abundance and the small amount of high quality regrowth.  相似文献   
119.
Accelerated expansion of wastewater services to small communities in the Middle East and North Africa (MENA) is essential in order to address serious concerns over water scarcity and pollution in addition to meeting the demand for convenience and protecting public health. Centralized and conventional wastewater systems are currently the preferred choice of planners and decision-makers in MENA. Water and funding are not available to provide these centralized conventional services to small communities. This paper presents an integrated approach to sustainable wastewater management for small communities in MENA under the severe water resources crisis. The approach calls for a paradigm shift from centralized conventional wastewater systems to decentralized wastewater systems. Management of wastewater in MENA should start at home. Wastewater generation should be reduced through a combination of domestic water conservation measures. On-site systems must be improved and monitored to control pollution and to recover water for non-potable water uses. Should the circumstances not allow the use of on-site systems, wastewater should be transported and managed through a community system applying the principles of decentralized wastewater management and using the settled sewers for wastewater transportation where appropriate. This approach will facilitate the accelerated and sustainable extension of environmentally responsible wastewater services to MENA's small communities. It offers great potential for cost reduction, accommodates the necessary domestic water conservation efforts, reduces freshwater inputs in wastewater transportation thus eliminating unnecessary demand on freshwater, reduces associated environmental risks and increases wastewater reuse opportunities.  相似文献   
120.
Stakeholder participation has become a key factor in the success of grassroots conservation and natural resource management programs. Yet the majority of program evaluations are conducted by external consultants for the purposes of accountability, rather than program improvement. Too often, systematic evaluations of conservation programs are not conducted at all. The objective of this study was to build the capacity of a grassroots conservation organization to conduct participatory evaluation, involving project stakeholders in the design, implementation, and use of evaluation. The study applied a conceptual model for participatory evaluation to the Wildlife Clubs of Kenya (WCK), the largest grassroots conservation program for youth in Africa, involving more than one million youth since 1968. Seven trainings in participatory evaluation were conducted with WCK staff, teachers, and community members. The 120 participants, representing nine WCK regions with 800 clubs, showed a significant increase in attitudes and knowledge regarding evaluation, as reflected by mean test scores before and after training. To institutionalize evaluation at WCK, existing organizational practices were assessed and used as a foundation for developing an evaluation system. Based on club competitions, a new evaluation initiative was launched called the WCK Incentive Program. Participants in all seven workshops identified indicators and sources of evidence for this evaluation system, which now serves as a basis for rewarding outstanding performance in WCK. This study revealed the importance of incentives for evaluation, the need to build on existing structures to promote organizational learning, and the necessity for the conservation community to commit resources to capacity building in participatory evaluation.  相似文献   
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