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Acacia auriculiformis Benth., Mimosaceae, has been introduced relatively recently as a plantation tree to the island of Unguja, Zanzibar. It has been reported to establish itself outside the plantations, but it is not known if the...
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Acacia auriculiformis Benth., Mimosaceae, has been introduced relatively recently as a plantation tree to the island of Unguja, Zanzibar. It has been reported to establish itself outside the plantations, but it is not known if the success of establishment depends on habitat quality. We investigated the occurrence of A. auriculiformis in 5-m-wide sample lines, which started from the edge of acacia plantations and reached farthermost the distance of 1 km. The results of 7.24 ha studied showed that: (1) A. auriculiformis occurred in most of the studied habitats in Unguja and appeared to be more abundant in deep soils than in shallow coral-derived soils. However, statistical analyses suggested that the species has little preference or avoidance towards any of the habitats, even though forests - the least disturbed habitats - seemed to have less acacias than other more disturbed habitats. (2) The number of acacias decreased rapidly with the distance from an acacia plantation, and most of the found acacias were still young, below three metres tall. Our results suggest that the invasion of A. auriculiformis is at its beginning in Unguja. If no preventive measures are taken, A. auriculiformis may have an increasing impact on local ecosystem in the future.
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While the decrease in flow is obvious in the Kikuletwa River, the mechanism leading to the decrease is unclear. We assessed the influence of vegetation cover change on dry season flow in the Kikuletwa River. The combined cover of ...
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While the decrease in flow is obvious in the Kikuletwa River, the mechanism leading to the decrease is unclear. We assessed the influence of vegetation cover change on dry season flow in the Kikuletwa River. The combined cover of closed and open forests decreased by 68% while closed and open forests decreased by 56% and 64% respectively. Land under agroforestry decreased by 25%, while that under annual crops increased by 41%. Grasslands increased by 116% and riverine vegetation decreased by 53%. Daily dry season flow showed a slightly decreasing trend in one of the stations despite all of them receiving water from the Rundugai natural springs. On the other hand, low flow indices indicated no statistically significant changes in the long-term average flow and there was no identifiable change in the rainfall amount. The majority (93%) of the local people perceived a changing rainfall pattern and decline in dry season flow in the Kikuletwa River. Changes in the dry season flow then can be associated with the identified land cover changes. Further research to substantiate the local people perceptions is important as indigenous knowledge may be good evidence for ascertaining changes in the natural environment.
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Although wild meat is an important source of protein across Africa, patterns and reasons for its demand are poorly defined. A study was conducted on consumption by inhabitants of ten villages in five districts to the west of Seren...
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Although wild meat is an important source of protein across Africa, patterns and reasons for its demand are poorly defined. A study was conducted on consumption by inhabitants of ten villages in five districts to the west of Serengeti National Park, Tanzania. The first sample of 600 villagers was systematically selected from village registers and surveyed using a questionnaire. The second sample consisted of 341 arrested illegal meat hunters. Nine species dominated by eland (Taurotragus oryx) and wildebeest (Connachaetes taurinus) in terms of meat taste and hunting vulnerability respectively were found to be most preferred or consumed. There were remarkable variations in consumption and preferences for each species amongst ethnic groups and localities. The economics of protein consumption indicates that wild meat is consistently cheaper and hence consumed more frequently than other meats. Respondents' topmost tasty meat - eland and topi (Damaliscus lunatus) - were rare; consequently, common species e.g. buffalo (Syncerus caffer) and wildebeest were the substitutes mostly consumed to supplement beef and fish. Presence of carnivore species on the menu clearly demonstrates survival techniques when availability changes. Wildlife managers should, therefore, bestow attention to the conservation of all species for a balanced ecosystem and species survival.
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Vegetation data in an early 20th century map from northern Tanzania are presented and discussed for its potential of expanding the analytical time-frame in studies of land-use and land-cover change. The starting point is that much...
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Vegetation data in an early 20th century map from northern Tanzania are presented and discussed for its potential of expanding the analytical time-frame in studies of land-use and land-cover change. The starting point is that much research on land-use and land-cover change suffers from a time-frame bias, caused by limitations in remote sensing data. At the same time, the use of historical maps as a complementary data-set is rather insignificant. Can information in historical maps be used to extend the baseline in land-use and land-cover change studies? The historical context of the vegetation data is evaluated, and as an illustration of its potential for interdisciplinary research on land-cover and ecosystems change, a section of the map is juxtaposed with a recent pollen record specifically addressing the impact of a 'large infrequent disturbance' (LID) event at the end of the 19th century. It is concluded that the vegetation data in the map are not likely to be reflecting an extreme situation due to the LID event. Finally, the historical vegetation data were visually compared with a national 1995 land-cover data set, illustrating the possibility of using the map data as a baseline in land-cover change studies.
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In 1994, rinderpest virus of African lineage 2 was detected in East Africa after an apparent absence of more than 30 years. In 1996, a disease search, based on participatory epidemiological techniques supplemented by serological a...
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In 1994, rinderpest virus of African lineage 2 was detected in East Africa after an apparent absence of more than 30 years. In 1996, a disease search, based on participatory epidemiological techniques supplemented by serological and virological analyses, was undertaken in southern Somalia and northeastern Kenya to collate past and current epidemiological information about rinderpest-compatible disease events, and to test the hypothesis that African lineage 2 rinderpest virus persists in populationsof transhumant cattle in the Somali ethnic areas. The findings in Afmadu in Lower Juba led the search for rinderpest to the communities in the Bardera area and then on to the Kenya/Somalia border areas between Mandera and El Wak. The herders had a specific knowledge of the clinical signs of rinderpest and provided detailed and accurate descriptions of cases. They differentiated between classical acute rinderpest and a milder syndrome characterised by an ocular discharge and diarrhoea, few oral lesions,corneal opacity and occasional mortality. The studies provided evidence for the endemic occurrence of rinderpest back to at least 1981, with a periodicity of five years in the incidence of the disease. After a period of high mortality in 1992 to 1993, around Afmadu, herders reported a mild disease, with occasional increases in mortality, from other areas of Lower Juba and the Gedo Region. Reports by herders of a rinderpest-compatible disease in the El Wak area were pursued until active cases were located and rinderpest was confirmed.
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The breeding pattern of the grass rat, Arvicanthis neumanni, was investigated in central Tanzania in 2002/2003. Nine hundred and forty-seven animals were captured in three age groups: juveniles, sub adults and adults. These age gr...
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The breeding pattern of the grass rat, Arvicanthis neumanni, was investigated in central Tanzania in 2002/2003. Nine hundred and forty-seven animals were captured in three age groups: juveniles, sub adults and adults. These age groups were present in the population for an extended duration, but there was an increase in the number of sexually active individuals and juveniles 2-3 months after the onset of the rains (December 2002-May 2003). A peak in reproductive activity occurred between January and April. Litter size ranged between 5.58 pl 0.42 and 6.1 pl 0.26 in two study sites. There were no significant differences in the number of embryos implanted in the right and left horns of the uterus of pregnant females (t = 0, P > 0.05 and t = 1.68, P > 0.05, respectively). Sex ratio of A. neumanni was not skewed to either males or females. Breeding was seasonal and seemed to be associated with seasonal variations in primary productivity, which relates to rainfall patterns.
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Hysterectomy is one of the most common gynaecological procedures performed worldwide. The magnitude of the complications related to hysterectomy and their risk factors are bound to differ based on locations, availability of resour...
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Hysterectomy is one of the most common gynaecological procedures performed worldwide. The magnitude of the complications related to hysterectomy and their risk factors are bound to differ based on locations, availability of resources and level of surgical training. Documented complications rates and their correlates are reported from high income countries while data from low- and middle-income countries including Tanzania is scare. This was a hospital based cross-sectional study conducted at a tertiary facility in northern Tanzania where 178 women who underwent elective gynecological hysterectomies in the department of obstetrics and gynecology within the study period were enrolled. Logistic regression was performed to determine the association between risk factors and occurrence of surgical complication where p-value of 2?h) (OR 5.02; 95% CI 2.18–11.5). Both uterine fibroid and adenomyosis had good correlation of clinical and histological diagnosis (p-value <?0.001). Bleeding and blood transfusion were the most common complications observed in this study. Obesity, previous abdominal operation and prolonged duration of operation were the most significant risk factors for the complications. Local tailored interventions to reduce surgical complications of hysterectomy are thus pivotal. Clinicians in this locality should have resources at their disposal to enhance definitive diagnosis attainment before surgical interventions.
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The establishment of plantations is impacting the large mammal populations of the Kilombero Valley, Tanzania. Animal spoors were used as a proxy for activity to determine the influence of teak stand age on mammals. Habitat variabl...
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The establishment of plantations is impacting the large mammal populations of the Kilombero Valley, Tanzania. Animal spoors were used as a proxy for activity to determine the influence of teak stand age on mammals. Habitat variables were compared between different aged stands to investigate the relationship between mammal activity and vegetation characteristics. Vegetation surveys found plantation composition to differ with age; with young stands characterized by slender teak trees, limited leaf litter, abundant grass layer and substantial bare ground. Older plantations contained a high leaf litter layer and dead wood, low grass abundance and minimal bare ground. Spoor transects revealed that mammal species number decreased as the teak matured. Of those vegetation variables tested, grass and bare ground abundance explained significantly the variation in species number and in individual species' habitat use between differently aged stands; therefore this habitat use was influenced by the foraging value of the plantation. This study showed that several species (some of which warrant conservation attention, such as elephant) use plantations <6 years old to a greater extent than plantations >6 years. Thus, there is a need for conservation measures, such as wildlife corridors and staggered teak planting to be continued, allowing large mammal movements in the valley.
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In developing countries, participatory land-use planning is seen as a panacea to mitigate land-use conflicts and enhance land productivity. This assumption has not been thoroughly tested in wildlife corridors. Three villages were ...
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In developing countries, participatory land-use planning is seen as a panacea to mitigate land-use conflicts and enhance land productivity. This assumption has not been thoroughly tested in wildlife corridors. Three villages were selected for this study. Several methods were used to provide indication of the performance of the plans against their stated objectives of mitigating conflicts and conserving wildlife corridors. Three hundred and fifty-eight households and eight park and extension workers were interviewed. In addition, focus group discussion with the nomadic Barabeig, field assessment and review of land-use plan/general management plan reports were carried out. Results reveal that land-use plans failed to achieve their set objectives. For example, 75% of the households held this view. Major causes of failure were insufficient participation by stakeholders in the planning process, lack of robust, transparent and accountable implementation strategies, inadequacy of qualified staff and lack of 'holistic approach' to the planning process. Taking these findings into account, an improved buffer zone land-use planning framework is suggested. For the framework to enhance both conservation and development and to enable policies and legislation, equitable benefit sharing and conservation education, initiation of compensation schemes for depredation caused by wild animals and intensification of patrols are required.
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