960 resultados para Folk literature - Africa, East


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Coral reefs are widespread along the east African coast and Seychelle islands. Their roles in island building and coastal protection are often underestimated, they are also important fishery habitats and major tourist attractions. The east African marine fishery production, estimated at 1.4-4.9 tonnes per km super(2), is principally a result of artisanal fishing. Siltation, trampling, and destructive fishing methods are the main cause of coral reef degradation along the east African coast and associated islands. Legislation has been implemented to protect coral reefs by establishing marine parks and reserves. However, poaching and anchor damage are widespread on these protected reefs. Legislative provision to increase the benefit to fishing communities may reduce poaching. The establishment of exclusive nature reserves may be one way to ensure preservation of some coral reefs in the region.

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Lake Victoria, in East Africa, has suffered from introductions and invasions of non-native species such as Lates niloticus, various tilapiine species, and Eichornia crassipes since the 1950s. These have had a devastating effect on the natural biological communities. This paper reviews the effects of the introductions on ecology, environment, fisheries and the local human population.

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This "Survey of Research and Scientific Services in East Arica 1947-1956" has been prepared by Dr. E. B. Worthington, who held the post of Scientific Secretary in the Office of the Chief Secretary to the East African Governor's Conference and subsequently in the Administrator's Office of the East Mrica High Commission during the period January, 1947-May, 1951. Dr. Worthington is now Secretary General of the Scientific Council for, Arica South of the Sahara

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An historical account is given of the development of the Lake Albert fisheries since Worthington's survey in 1928. It is noted that the development of the fisheries was related to, and dependent upon, improvements in the type of gear and canoes, an incFease in the number of canoes and outboard engines in use, improved marketing facilities and better road communications. Summarized data, collected mainly since 1954, has been analysed and tabulated to show annual exports to the Congo, total annual catches 'and annual catches of individual species. A change in the relative abundance of the various species in the annual catches is described. It is noted that this change was caused by a change-over from large to small mesh size gill-nets, and that it was associated with an increased demand within Uganda for the smaller species of fish, such as Aleste's baremose and Hydrocynus forskahlii. A brief description of fish processing and marketing in the Lake Albert region is given, which emphasizes the suitability of salt-cured fish to the social and physical environment of the area. Finally, a summary of a recent survey of the potential fish resources of the lake is given in the discussion, and estimates of the 1965 catch at the north and south ends of the lake are compared with the findings of the survey. This showed that there is little danger of overfishing the Alestes baremose stocks of the Wanseko area at the 1965 rate of exploitation of the species, and that the total catch for 1965 at the south end of the lake was well below the estimated annual sustainable yield from the area.

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Thirty-three groups of geochemically related natural lake and river waters collected from 368 sites scattered over East and West Africa, were investigated to determine correlations between their various ions and the patterns of change in their ionic composition across the African continent. The following nine significant correlations were found to exist in the entire area or in a major part of it: sodium and potassium; sodium and chloride; sodium and sulphate; potassium and ammonium; potassium and chloride; ammonium and nitrate; calcium and magnesium; magnesium and chloride; sulphate and chloride. When compared with the world average composition. The concentration of potassium in these waters was found to be high, that of calcium and nitrate was low. With respect to the area of East Africa only, trends in the pattern of change involving the ionic composition of the lake and river water and the longitude at which the sites were present, were found to exist for the ratio of sodium: conductivity (which showed an increase in the direction of West to East), magnesium: conductivity, and for the sum of calcium and magnesium: phosphate was generally found to increase in East Africa in the direction of west to East.

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A shallow, highly productive, tropical lake is descrihed with a brief history of its commercial fishery. Three separate assessments of the present (1967-1970) yield are compared, with an apparent confirmation of the values derived from Fishery Department statistics over a period of 20 years. The seasonal change in the catch is noted with, an apparent anomaly shown by ohservations of canoe landings. Long-term trends during the period 1950-1969 are considered with a brief discussion of possible future trends in the fishery.

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Nothobranchius guntheri is found in seasonal pools and streams in the coastal region of Tanzania. A population recurring annually in a pond near Kilosa has been studied. Growth in length was rapid and maximum mean lengths were attained within 11-12 and 7-8 weeks of hatching by males and females respectively. Males grew larger and exhibited wider variation in length than females. N. guentheri shows clear sexual dichromatism. No significant inequality in the sex ratio was found. Females with ripe eggs were found 7-8 weeks after hatching. Spawning continued throughout adult life and fecundity increased markedly with increasing length. In laboratory aquaria, aggressiveness between adult males was noted and females were actively driven on to the substratum preparatory to spawning. The diet of the fish pond consisted chiefly of aquatic and terrestrial insects, of which midge larvae and pupae were the most common. N. guentheri is exploited by man in the aquarist trade and for the biological control of mosquitoes. An extended redescription of the species is appended which includes N. melanospilus (Pfeffer) as a synonym.

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In 1967 the then University College of Dar es Salaam built a small laboratory on the shore at Kunduchi, 16 km from the main campus and 24 km north of Dar es Salaam. This was used for undergraduate field courses, and as a base for staff from the University to carry out research. It soon became apparent that the urgent need for studies of the marine environment in the East African area, and the lack of existing facilities, necessitated the development of the Kunduchi Marine Biology station into a research establishment with its own staff of full time scientists. This operation began in 1970: necessary structural modifications have been made to the building, staff have been recruited, and the station has been equipped with an adequate range of field and laboratory apparatus. A varied programme of research is now actively under way.

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Protein deficient diets are a standard way of life in many parts of East Africa;this of course tends to result in shorter life expectancy and chronic ill-health. Population increase is sufficiently high to outdistance the economic gains that may be made in various fields. With recurrent shortages of basic commodities not only in East Africa, but in many parts of the world, it is becoming increasingly clear that agricultural production practices must be maximised rapidly in order to meet the world's constantly expanding need for food. Here in East Africa, while our food requirements can be met most of the time, our protein requirements are far from being met. Yields from traditional fishery resources, must therefore be increased. The farming of fish (aquaculture)adds a new dimension to food production in general and high quality protein production in particular, in that it can be incorporated into other agricultural production activities.

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http://www.archive.org/details/garenganze00arnouoft/

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Beginning with a panoramic analysis of the role played by East Timorese poets in the struggle for liberation from Portuguese and Indonesian colonial rule, this article examines the extent to which an East Timorese national identity and unity repeatedly featured in the poetry of the 1970s and 80s are represented in contemporary Timorese literary production. By reading the work of the novelist Luís Cardoso, and the poets Abé Barreto and Celso Oliveira, the article also assesses whether the independent nation envisioned earlier by those such as Borja da Costa, Fernando Sylvan and Xanana Gusmão, has been realised. In doing so, critical attention is brought to bear on the intimate relationship between the specific material and political circumstances of East Timor and the literature produced in colonial and postcolonial moments in the nation’s history.

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We dated a continuous, ~22-m long sediment sequence from Lake Challa (Mt. Kilimanjaro area, Kenya/Tanzania) to produce a solid chronological framework for multi-proxy reconstructions of climate and environmental change in equatorial East Africa over the past 25,000 years. The age model is based on a total of 168 AMS 14C dates on bulk-organic matter, combined with a 210Pb chronology for recent sediments and corrected for a variable old-carbon age offset. This offset was estimated by i) pairing bulk-organic 14C dates with either 210Pb-derived time markers or 14C dates on grass charcoal, and ii) wiggle-matching high-density series of bulk-organic 14C dates. Variation in the old-carbon age offset through time is relatively modest, ranging from ~450 yr during glacial and late glacial time to ~200 yr during the early and mid-Holocene, and increasing again to ~250 yr today. The screened and corrected 14C dates were calibrated sequentially, statistically constrained by their stratigraphical order. As a result their constrained calendar-age distributions are much narrower, and the calibrated dates more precise, than if each 14C date had been calibrated on its own. The smooth-spline age-depth model has 95% age uncertainty ranges of ~50–230 yr during the Holocene and ~250–550 yr in the glacial section of the record. The d13C values of paired bulk-organic and grass-charcoal samples, and additional 14C dating on selected turbidite horizons, indicates that the old-carbon age offset in Lake Challa is caused by a variable contribution of old terrestrial organic matter eroded from soils, and controlled mainly by changes in vegetation cover within the crater basin.

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Increased globalisation within the British AEC (Architectural, Engineering and Construction) sector has increased the need for companies to transfer staff to manage their overseas operations. To be able to perform abroad, expatriates must harmonise themselves to the conditions prevailing in the host country. These include getting accustomed to living, working and interacting with the host country nationals. The process is commonly referred to as 'cross-cultural adjustment'. Various factors influence the process of adjustment. In order to identify these issues, a qualitative study was undertaken, which mainly comprised of comprehensive literature review, individual interviews and focus group discussion with British expatriates working on international AEC assignments in Middle Eastern countries. Through interpretative approach, the current study aims to understand the concept of cross-cultural adjustment of British Expatriates based in Middle East and their influencing factors.

The findings suggest that success of expatriation does not entirely rest on an expatriate's ability but also on organisational support and assistance that expatriates receive prior to and during the assignment. Organisational factors such as selection mechanisms, job design, training, logistical and social support, mentoring, etc., influence various facets of expatriate adjustment. Striking cultural contrasts between British and Arab culture both in work and non work situations also dictate the level of support required by the expatriate, suggesting that relocation to less developed, remote or politically unstable regions, demands additional support and consideration by the parent company. This study is relevant to the AEC companies employing British expatriates, who need to be cognisant of the issues highlighted above to make rational and informed decisions when handling international assignments in the Middle East.

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Weathering-rind thicknesses on pebble-and cobble-size sediment have been used for the past half-century, at least, as an age indicator of postdepositional time following a geologic event. In mountainous terrain, rind thickness is taken as a measurement of weathering over time frames of 0.5 m.yr.; variable thicknesses are used to discriminate relative ages of glacial deposits. The effects of chemical and physical weathering that together produce rinds are only rarely considered, and most research objectives have centered on lichen alteration of clast surfaces. Recent microscopic analyses of weathering rinds on volcanic clasts of similar to 70.0-ka to similar to 2.0-m.yr. age produced new data on weathering products as well as unexpected incorporated biotic materials undergoing diagenesis. The question as to how much physical/mineral/chemical/ biotic paleoenvironmental data might be archived in rinds is discussed. The character and classification of organic materials undergoing diagenesis are also discussed.