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1.
SUMMARY

Bwindi Impenetrable National Park and the Virunga Volcano region are the last remaining habitats of the highly endangered mountain gorilla (Gorilla beringei beringei). This conservation area, shared by Uganda, Rwanda and the Democratic Republic of Congo, also acts as a refuge for biodiversity and high endemism in the Albertine Rift of Central East Africa. This particular region has suffered from a number of years of civil strife, which have severely affected the management of these forests. This paper will explore the experiences of the International Gorilla Conservation Programme (IGCP) obtained throughout the development of regional processes that are working towards establishing a transboundary-protected area. The establishment of a regional framework and tools utilized are described. The costs and constraints incurred by the IGCP and the resulting positive impacts on conservation are also highlighted.  相似文献   
2.
The research community increasingly analyses global environmental problems like climate change and desertification with models. These global environmental modelling studies require global, high resolution, spatially exhaustive, and quantitative data describing the soil profile. This study aimed to develop a pedological approach that takes stock of available legacy and auxiliary data to create a global, 30 arc second soil property database for modelling. The methodology uses the Harmonized World Soil Database and the ISRIC‐WISE 3.1 soil profile database. Auxiliary information at 30 arc second resolution for various landscape properties is used to describe the variation in landscape properties (temperature and precipitation, topography, elevation, land use, and land cover). Complex mapping units of the HWSD were first disaggregated using a digital elevation model and toposequences to generate delineated areas described by a single soil type. Secondly, ranges of soil properties per soil type were determined using the soil profile data. Then a meta‐analysis on a broad literature survey was used to develop a simple model that, based on landscape properties at a particular location, determines the position within these ranges and thus provides an estimation of the local soil properties. Finally, the model was implemented at the global level to determine the distribution of soil properties. The methodology, denominated S‐World (Soils of the world) resulted in readily available, high resolution, global soil property maps that are now available for environmental modelling. © 2016 The Authors Journal of Behavioral Decision Making Published by John Wiley & Sons Ltd.  相似文献   
3.
Most of Rwanda's wetlands are being reclaimed under government schemes with the aim of growing rice as the main crop. In the present study, information on farmers' knowledge and perceptions of agricultural wetland management was collected in Cyabayaga and Rugeramigozi wetlands. The two wetlands were selected as representatives for typical reclaimed wetland agriculture in Rwanda. They provide contrasts in both environmental and social terms. Three tools were used to investigate farmers' knowledge and perception of agricultural wetland management: (i) household survey; (ii) focus group discussions; and (iii) transect walk. The major constraints identified by farmers in the two wetlands were water shortage and lack of availability of improved seeds and high prices of fertilisers. The primary benefits from wetlands for farmers are income generation in Cyabayaga and food security in Rugeramigozi. The most commonly reported concern about the wetlands in the Cyabayaga and Rugerameragozi was that they are a source of malaria. Rice is an important crop in both wetlands, whereas farmers in Cyabahaga wish to continue cultivating rice, Rugeramigozi farmers prefer to grow rice only after it has been tested for its adaptability. Farmers have sufficient knowledge on the causes and the potential solutions to overcome most constraints. They know that soil suitability is closely related to relief. They classify soils by a number of criteria and choose crops accordingly. Any programme designed to address wetland management in the region will have to take account of farmers' knowledge and adopt a holistic view of wetland management. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
4.
In an attempt to identify solutions to the effects of erratic rainfall patterns and droughts that limit agricultural production growth, the Rwandan government has recently increased investments in irrigation development. In this study, we analyze the adoption of small-scale irrigation technologies (SSITs) and its impact on land productivity using cross-sectional data from a sample of 360 farmers in Rwanda. The study uses the propensity score matching technique to address potential self-selection bias. Our results reveal that adoption decisions are significantly influenced by factors such as education, farm size, group membership, gender, extension services, access to credit, access to weather forecast information, risk perceptions, access to a reliable source of water for irrigation, awareness of rainwater harvesting techniques, and awareness of subsidy programs. In addition, the results show that the adoption of SSITs has a significantly positive impact on land productivity. The study concludes with policy implications that highlight the need to promote the adoption of SSITs among farmers as a strategy to improve agricultural productivity and food security in Rwanda.  相似文献   
5.
Throughout Rwanda, terracing was reintroduced in 1973 as the major conservation practice to minimize soil loss on its steep agricultural lands.1 Terracing has been partially successful in reducing soil losses resulting from nonchannelized runoff, the goal of this practice. However, because of the widespread fragile environmental conditions in the highlands, soil fertility has decreased and soil acidity increased in numerous fields as a direct result of the terracing. To maintain sufficient agricultural yields, within the constraints of a low resource agricultural system, farmers have responded to the acidity and soil fertility problems by systematically removing a portion of the terrace berm during field preparation. This practice, in response to the changing environmental situation due to terracing, results in significant amounts of soil displaced downslope year after year. This human-induced soil erosion process seriously counters many of the intended benefits of terrace construction and is contributing to the land degradation problem. The results of this study emphasize the need for both conservation strategies and the measurement of soil loss to be sensitive to human-induced as well as natural erosional processes. By not considering the human response to terrace construction, the benefits of this conservation practice have been seriously offset.  相似文献   
6.
This paper investigates the adoption of bench terraces by applying a three‐stage analysis using data from 301 households in the highlands of Rwanda. Ongoing adoption of bench terraces is ‘unpacked’ to consider both adopters willing to retain and increase the intensity of using terraces already constructed and new adopters willing to develop new bench terraces. Results suggest that farmers' inability to maintain existing terraces may explain the reluctance to adopt new terraces. The same inability explains why some of the terraces constructed earlier are not well maintained and fully used by farmers in northern and southern Rwanda. Policy actions aimed at improving farmer's capacity to invest in complementary inputs will sustain future generations of soil and water conservation measures in Rwanda. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
7.
The objective of this study was to assess the reproductive performance of Rwandan cattle and determine the effects of husbandry practices on reproduction. One hundred and fifty Ankole and Crossbreed cattle from 87 farms, were body condition scored (BCS) on a scale of 1(lean) to 5 (fat), and examined rectally for pregnancy and ovary size and structures present. Questionnaires were completed by the farmers to obtain information on husbandry and management practices. The mean age of onset of puberty was 27.7 ± 10.4 months, the interval from parturition to first oestrus was 8.7 ± 7.8 months, calving index was 16.8 ± 5.2 months and 44% (95% CL 0.36-0.52) of cows examined rectally were anoestrus. Crossbred cattle reached puberty younger than Ankole cattle, 23.4 ± 10.4 and 28.4 ± 9.6 months respectively (p < 0.05; t = 1.944; df = 121). Cows in poor BCS (< 2.5) are 1.67 times as likely to be in anoestrus as those with higher BCS (≥ 2.5) (χ2 = 9.476; df = 2; p < 0.01). Increased weaning age resulted in increased calving index (p < 0.001; t = −3.60; df = 38). Reproductive performance of Rwandan cattle is poor. Many of the problems can be attributed to husbandry practices and lack of experience and training in raising cattle.  相似文献   
8.
Jan Moeyersons   《CATENA》2003,50(2-4):381-400
This article presents new quantitative evidence that land use in Rwanda contributes to the development of hillslope incisions.Two types of hillslope incisions can be distinguished in southern Rwanda. Incisions of the first type drain an area depending on the form and extension on the natural topography and geology. The Runyinya gully (25°) and the Rugabano soil slippage (39°) are two examples. On a logarithmic plot of critical slope inclination at the incision head versus drainage area towards the incision head, both incisions lay sensibly to the right of the Montgomery–Dietrich (M-D) envelope. The latter gives the range of these topographical thresholds for gully and mass-wasting incision in parts of North America. The Runyinya and Rugabano cases obey the linear equation:
Scr=(±0.6)A−(±0.6)
where Scr=critical slope gradient (tangent of slope in °) at the gully head or the scar and A=the area (ha) drained towards the incision head.Hillslope incisions of the second group rely on a run-on area larger than normal because they are localised at the ‘outlet’ of artificially runoff-collecting systems like roads, soil conservational contour trenches, tracks and other linear landscape elements. Such systems often drain a surface much larger in extension than the natural run-on area to the ‘outlet.’ These hillslope incisions, taking into account their artificially big drainage area, concentrate more or less along the line:
Scr=(±0.3)A−(±0.6)
This line is about in the center of the Montgomery–Dietrich envelope. If, however, only the natural drainage area of these ‘outlet’ incisions is taken into account, all points fall close to the left border or even to the left of the Montgomery–Dietrich envelope. This indicates a much higher probability for incision in those localities receiving supplementary runoff or interflow from outside the natural drainage area. In the case of a soil slippage at Rwaza Hill, detailed stability calculations show that the slope failure should be due to excessive water infiltration into the bottom of a trench. The digging of the trench provoked an increase in the area drained to the slippage head by a factor of 6.The phenomenon of ‘forward’ erosion is compatible with the existence of threshold combinations of slope and drained area. For slopes steeper than 7–8°, the phase of regressive erosion does often follow the forward incision event with a delay of several years or more.Finally, the scanty data set now available for Rwanda suggests that the drainage area critical to hillslope incision on the red-brown ferrallitic soils in Rwanda might be nearly twice as big as those in North America.  相似文献   
9.
Human–wildlife conflict (HWC) presents an increasing challenge to conservation, particularly in densely populated parts of low-income countries. This article assessed one form of conflict, crop raiding by forest-dwelling primates, along the boundary of a tropical montane forest fragment (Gishwati Forest) in western Rwanda. Variation in species involved, crops affected, differences in magnitude with season and distance to the forest boundary, and the nature of mitigation efforts were assessed through semi-structured interviews with farmers and field-based observations during June and July 2009. Substantial losses of crops were reported, with replacement costs possibly reaching 10–20% of total household income. Chimpanzees (Pan troglodytes) and Cercopithecus monkeys were the sole reported raiders, mainly affecting maize and legumes. Mitigation was restricted to guarding of crops and modification of farming practices, the latter potentially having significant dietary consequences for subsistence farmers. These findings highlight the potentially high economic costs, and food security effects of HWC.  相似文献   
10.
Summary The potato has been grown in numerous developing countries for many years. Archival material on long-term production/yield trends expressed in graphic form, together with data on previous cultivar introductions, can be an important indicator of potential major constraints to production. As National Potato Programmes are being developed in these countries such data, when used in conjunction with sound agronomic training, can ensure the establishment of a realistic approach to crop development.  相似文献   
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