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41.
Concentrations of perfluorooctane sulfonate (PFOS) were measured for the first time in major rivers within southwest, Nigeria. PFOS was concentrated from water and sediment using solid-phase extraction, identified and quantified with high-performance liquid chromatography coupled with tandem mass spectrometry. Concentrations of PFOS ranged from 1.71 to 16.19 ng L?1 in water, and from 1.64 to 10.29 ng g?1 in sediments across all locations. Comparatively, the concentrations of PFOS observed in this study were within the range ever measured in the environment. Field-based sediment water distribution coefficients (log Kd, L kg?1) ranged from 2.08 to 3.56. While no correlation was observed between Kd and organic carbon contents, there was significant positive correlation between Kd and salinity (r2 = 0.7867), which suggested that activities capable of increasing salinity can enhance PFOS removal from the environment.  相似文献   
42.
The concentrations of lead and copper in sclerotium of the mushroom Pleurotus tuber-regium widely consumed in Southeastern Nigeria were determined. The specimens purchased from different markets were mineralized with H2SO4 and H2O2 and analyzed using flame atomic absorption spectrophotometer. The concentrations of Pb ranged from 0.2?±?0.1?mg?kg?1 to 0.8?±?0.5?mg?kg?1 with approximately 91% of the results being below 1?mg?kg?1. The concentrations of Cu ranged from 0.5?±?0.2?mg?kg?1 to 1.2?±?0.6?mg?kg?1 with 78% of the results below 1?mg?kg?1. The results were compared with the literature and levels set by regulatory authorities, with the conclusion that the consumption of sclerotium does not pose a toxicological risk. The low Pb content of the studied products would contribute to only about 1% of the provisional tolerable weekly intake of Pb. The Cu contents would contribute to nutritional intake of the metal in the general population. It is recommended that the outer layers of the sclerotia be properly scrapped before use to reduce metal contamination from exogenous sources.  相似文献   
43.
SUMMARY

A cross-section survey of five states in Nigeria was derived through a stratified random sampling technique in 1999–2000 to assess the contribution of traditional knowledge in environmental conservation. Data were collected through a combination of questionnaire survey and discussions with stakeholders, with field assessment of herb gardens. Interviews were held with 1953 respondents composed of women, men and youths drawn from 20 settlements in 10 local government areas in the savanna and rainforest ecological zones.

The results derived from data analysis indicated that: (i) the rural communities were willing to accept integrated rural land-use practices that would conserve species and habitats, sustain the rural economy and the socio-cultural lifestyles of the people; (ii) the people at the local level had some basic knowledge about species and habitats, and have been conserving the forests with traditional land tenure rights; and (iii) environmental projects acceptable to the rural communities must be beneficial to the people, participatory, integrated with traditional knowledge and based on local needs.  相似文献   
44.
SUMMARY

The humid zone of Nigeria has traditionally been considered unsuitable for extensive cattle production because of the prevalence of tsetse fly. Over the years, nomadic pastoralists, mainly Fulani, from the northern part of the country paid seasonal visits to this zone in search of pasture and water for their cattle during the dry season when the threat of the tsetse menace is less. The recent increase in the number of settled pastoralists has been associated with changing trends in the ecology and economy of the zone.

Relying on recent survey data, this paper attempts a systematic analysis of the adaptive strategies of the Fulani in pursuit of a sedentary lifestyle in the humid frontier of southwest Nigeria. Some of the adaptive strategies identified include: establishment of grazing orbits within a 20 km radius of their settlements, adjustment of herd size and structure, adoption of a multiple livelihood system, production of arable crops and appropriation of traditional social structures and kinship networks for herd management.

Long-term insecure land-holding arrangements, incessant seasonal bush burning for regeneration of pasture by the Fulani and the gradual destruction of the native forest cover are some of the problems arising from the sedentarisation of livestock production in the area. It was observed that the present land-use arrangement, even though it appears to guarantee the pastoralists security of tenure in the short term, is not sustainable in the long run, given the increasing commercialization of land in the area and rapid population growth. It was, therefore, concluded that government should put in place a land redistribution arrangement that will ensure secure land ownership by the Fulani. Development initiatives in the area should also focus on reinforcing those traditional practices of the Fulani that would guarantee a sustainable land-use system in the area.  相似文献   
45.
Despite large investments that have gone into meeting the challenges of effective waste management in urban Nigeria, there is little evidence that such efforts are having their expected impacts. Consequently, much attention has been drawn to the need to evolve more sustainable waste management strategies. Drawing on data from in-depth interviews among the Ngwa of southeastern Nigeria, some useful indigenous solid and liquid waste management techniques, in the search for solutions to the current waste management crisis in urban Nigeria, have become evident. These indigenous techniques and practices, which include ingenious and careful waste segregation and sorting, selective burning and burying, composting and conversion, etc., offer scope for meeting the challenges and addressing the limitations of current waste management in urban areas, especially if they are supported by appropriate inputs from modern technology.  相似文献   
46.
ABSTRACT

This study explores the experience of the sub-urban slum residents in Okpoko (Anambra State), Ngwa-road Aba (Abia State), Ajegunle (Lagos State) and Gwagwalada (Abuja), to underscore the elitist and western contexts of Covid-19 lockdown and physical distancing policies. The study apprehends these policies as being counter-productive due to Nigeria’s peculiar socio-economic circumstances, and brainstorms on the need and prospects for adaption and institutionalisation of an indigenous Afro-centred approach towards the containment of the Covid-19 pandemic. The use of herbal mixtures or local concoctions such as parboiled garlic cloves, lemon and ginger juice in the treatment and/or prevention of Covid-19 pandemic is a popular home-grown indigenous approach/practice which is generally believed to have inhibitory effects against Covid-19 by majority of the local people. These herbal remedies should be formally investigated, validated and encouraged in Nigeria as an alternative indigenous approach for the prevention and treatment of Covid-19 pandemic.  相似文献   
47.
The levels of total petroleum hydrocarbons in two commonly consumed benthopelagic shellfishes, Macura reptantia and Procambarus clarkii, harvested from benthic sediment of Qua Iboe Estuary were determined using a gas chromatography with flame-ionization detector. Seventy-two (72) samples each of benthic sediment and the shellfishes were collected monthly between June 2003 and February 2004 covering the peak periods of the wet and dry seasons. Concentrations of hydrocarbons were highly variable and ranged between 5.00 and 232.00 μg/g dry weight of benthic sediment, 3.05 and 11.30 μg/g dry weight of M. reptantia, 1.62 and 9.00 μg/g dry weight of P. clarkii. Pearson’s correlation analysis of total hydrocarbon concentrations in subtidal sediments with levels in the fauna species yielded positive significant (P < 0.05) correlations in M. reptantia (r = 0.737) and P. clarkii (r = 0.924). This is indicative of a long term and chronic accumulation of hydrocarbons in the estuarine ecosystem, reflecting the potential for exposure of the resident biota and the risk to human health.  相似文献   
48.
Solid waste poses a serious problem to government agencies and people in third world cities. Recycling as a way of managing waste has received relatively little attention. This paper examines the role of waste scavengers in the waste recycling process. The preliminary findings reported here indicate that the waste scavenger could be incorporated formally into the recycling process. Using plastic waste as an example, it is demonstrated that such recycling is economically viable.  相似文献   
49.
This paper attempts to provide an empirical basis for planning the optimisation of public outdoor recreational potential in Benin City, Nigeria. The study is seen as a partial analysis in that it considers only the deferred component of demand, and only with public recreational facilities. It identifies a mismatch between demand for and provision of facilities, due to an inadequate planning system.  相似文献   
50.
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