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1.
Cleophas Lado 《GeoJournal》1998,45(3):165-176
In many developing countries, research institutions or centres have been established to develop and/or adapt technologies that would help agricultural development. This is particularly true in Africa where national efforts have been supplemented with international research institutes. Although some modest progress has been achieved in improving agricultural technology, on the whole, the improvement record is not quite encouraging among the small-scale farmers. In many areas, either there are no improved technologies, or where they exist, are unacceptable by farmers. However, where useful technologies exist, their spread has been very limited and where they have been adapted, the benefits only accrue to a small segment of the community. The logical question posed is: why and how do we find ourselves in the current situation? This paper considers the view that to understand fully why the available technologies have remained largely at the research centres, there is need to examine the whole process of research, development, dissemination and utilization of agricultural technology. It is significant to investigate the structural constraints and prospects under which those involved in the process work, their motivations and the interactions between different groups. The traditional ‘top-down’ of development strategy should be supplemented with farmers' indigenous knowledge, and programmes encouraging transfer of agricultural technology should include institutional support. Only by the identification of farmers' environmental and resource utilisation, preferences, socio-economic circumstances and constraints can a development programme of optimum meaning to farmers be devised and implemented with success.  相似文献   

2.
B. McCusker  E.R. Carr 《Geoforum》2006,37(5):790-804
Land use change and livelihood systems are often analyzed separately or with one “driving” the other. This “driver-feedback” relationship has been buttressed by approaches to social process that are often far too static. Actors are confronted with a bundle of choices that they must negotiate as they create pathways of change. These choices are always bound up in relations of power and the knowledges that are the conditions for and results of these relations. We suggest that land uses and livelihood are different manifestations of the social processes by which individuals and groups negotiate the everyday conditions that shape their lives. We propose a framework that extends current understandings of the relationship between land use change and livelihoods by treating social relations of power as the entry point into this complex relationship. We underpin our arguments with empirical examples from South Africa and Ghana that locate power/knowledge relations in the context of social change in both study areas.  相似文献   

3.
Overlap of Karoo and Ferrar Magma Types in KwaZulu-Natal, South Africa   总被引:3,自引:0,他引:3  
A suite of mafic dykes from the Underberg region of southernKwaZulu-Natal (South Africa) were intruded at 178 Ma, coincidentin age with the major Okavango Dyke Swarm of Botswana, and alsocoincident with minor Karoo-related intrusions of the northernand central Lebombo. The dykes are all low-Ti–Zr tholeiites,they trend NW–SE and are presumed to continue into theKaroo central area of the Lesotho Highlands. In many respects,the Underberg dykes are similar to the majority of the low-Ti–Zrvolcanic and subvolcanic intrusions of the Karoo; however, their87Sr/86Sr and Nd isotope ratios are either ‘Ferrar-like’(87Sr/86Sr 0·710; Nd < –3) or transitional betweenKaroo low-Ti–Zr and Ferrar low-Ti magmas. A potentialFerrar source for at least some of the Underberg dykes is supportedby anisotropy of magnetic susceptibility analyses of the dykesuite, which demonstrate absolute flow direction from the SEto the NW, consistent with Gondwana reconstructions. The roleof crustal contamination and combined fractional crystallizationis also demonstrated to have played a key role in the petrogenesisof the Underberg dykes, involving a local upper crust contaminant.However, the composition of the ‘Ferrar-like’ dykescannot be easily explained by AFC processes, but they do demonstratethat melting of a lithospheric mantle source enriched to a smalldegree by subduction-derived fluid was also important. KEY WORDS: dyke; basalt; crustal contamination; large igneous province  相似文献   

4.
5.
Airborne magnetic data and Landsat imagery, as well as time-domain electromagnetic soundings, were used to assess groundwater potential of the region around the town of Mafikeng in North West Province, South Africa. Lineaments were extracted based on on-screen digital data derived from magnetic and Landsat 7 imagery. The relationship between lineament-intersection density and borehole yield was assessed using statistical analysis. The results were discussed with respect to factors that determine the groundwater potential of the area. Correlation between lineament-intersection frequency and borehole yield is 60?C65% in the south and southeastern parts, and 45?C50% within 5?C30?km radius of Mafikeng. The eastern and western parts of the study area are characterized by weak or no correlation. Areas that correspond to high correlation between lineament-intersection frequency and borehole yield suggest the significance of cross-cutting structures in controlling groundwater potential zones, while results that suggest low or no correlation represent the influence of other factors. The overall results demonstrate that the combined analysis of airborne magnetic data, satellite imagery, borehole yield and ground-based time-domain electromagnetic soundings provide the best approach for groundwater assessment within the hard rock and carbonate terrains of the study area.  相似文献   

6.
7.
Cheryl McEwan 《Geoforum》2003,34(4):469-481
This paper considers the ongoing political transformations in South Africa in the context of debates about good governance and participatory democracy. It first appraises the current transformations of local government in South Africa, focusing specifically on relationships between gender equality and citizenship on the one hand, and local government policy, legislation, and community participation on the other, and then explores meanings of participation and how they inform approaches towards local socio-economic development. The findings of primary research conducted with civil society organisations and black women in communities in the Cape Town metropolitan area are explored through three interrelated themes. First, the model of structured participation that is central to South Africa’s democratic transformation is assessed from the perspective of black women. Second, cultures of alienation, both within local governance structures and amongst black women and the extent to which recent restructuring is combating or contributing to these are explored. Third, how participation policies are dealing with conflict within and between target groups are analysed, whether stakeholder group politics obliterate important differences in interests and whether alternative structures might be more effective in terms of women’s participation and empowerment. Finally, the findings are interpreted in relation to theoretical concepts of good governance and participatory democracy, and the potential and problems of realising South Africa’s transformation process toward developmental local government are assessed.  相似文献   

8.
Women in many rural areas of the US often engage in small-scale businesses as one of several avenues for contributing to household incomes. In those geographical areas that contain a significant minority population, many of the women's businesses display the cultural diversity of the regions in which they live. Likewise, women's roles as economic providers as well as wives and mothers are reflected in the manner in which they operate their businesses. Candida Brush suggests that women's strategies for operating their businesses are highly integrative because women's business decisions are intertwined with familial responsibilities, household economic demands and desires to contribute to their communities. Hispanic and Native American women in the Four Corners region of southwestern US and African American women in central Virginia participated in interviews in which they responded to numerous short answer and open-ended questions about their businesses and decision-making strategies. From these interviews an image emerges of rural minority business women who are operating their businesses at the nexus of family obligations, economic necessities, cultural ties and with a commitment for serving their communities. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

9.
The emergence of an environmental movement in post-apartheid South Africa has involved the reframing of the environment as a ‘brown’ issue, articulating the discourse of social and environmental justice and a rights-based notion of democracy. Environmental movements have pursued a dual strategy of deliberation and activist opposition. Environmental movements have deployed science to pursue the strategic task of democratic opposition and have established networks of environmental knowledge and expertise. Ecological modernization is the dominant approach to environmental governance and adopts a science-based policy approach. In this context the regulation and management of the environment is premised on the need for science, which provides the authoritative basis for a regulatory response. In local environmental movements, there exists a fundamental tension between a cumulative history of lay knowledge about pollution and the lack of official acknowledgement of qualitative narratives. This is accompanied by a lack and suspicion of reliable official data. Environmental movements have thus employed ‘civic science’ strategically to place the issue of air pollution on the political agenda. This paper uses the case of environmental politics in Durban to reflect on the ways in which civic science and lay knowledge, together constituting community hybrid knowledge, are produced and disseminated in order to pressure the state and capital. The three ways in which knowledge is deployed are: to frame environmental problems, in strategies of oppositional advocacy, and in deliberative policy forums. Empirical analysis shows that civic science is produced through knowledge networks, and both lay knowledge and civic science are opportunistically used by environmental movements to engage both inside and outside formal policy making arenas. This deployment of hybrid knowledge by environmental movements represents a broader challenge to the power of science and technology based on increasing evidence of the hazards and risks facing ordinary people in their daily lives.  相似文献   

10.
《Gondwana Research》2002,5(3):581-589
Magnetic susceptibilities were measured on a representative collection of Archaean granitoids of the Barberton region using a portable KT5 magnetic susceptibility meter. The studied granitoids comprise, (1) syn-tectonic tonalite-trondhjemite-granodiorite (TTG) granitoids (132 samples), (2) late-tectonic calc-alkaline granitoids (402 samples) and (3) post-tectonic low-Ca and high-Ca granitoids (12 samples). Most of the early-stage syn-tectonic granitoids (∼3450 Ma) have low magnetic susceptibilities, less than 3 × 10−3 SI units, and correspond to ilmenite-series granitoids. The late-stage Kaap Valley tonalite pluton (∼3230 Ma) contains sporadically distributed higher magnetic susceptibility values (greater than 3 × 10−3 SI units), which are less than one-third in magnetic susceptibility of typical magnetite-series TTG of the Japanese Island Arc and thus strictly belong to an intermediate series. The Barberton TTG suite is essentially derived from reduced amphibolitic lower crust that reflects the anoxic nature of the Earth surface during the Archaean Eon. The more oxidized nature of the Kaap Valley tonalite may be generated in an oxidized lower crust by fluids squeezed out of the subducting plate.Late-tectonic granodiorite - adamellite batholithic complexes (∼3105 Ma) belong mostly to the magnetite series, and seem to suggest that relatively oxidized continental crust, reflecting oxic atmosphere and subduction mechanism operating, had evolved it by this time. Post-tectonic granitic plutons formed largely between circa 2900 Ma and 2700 Ma can be subdivided into low-Ca ilmenite series and high-Ca magnetite series.  相似文献   

11.
This paper is concerned with the relationship between safety and mobile phones with particular reference to Sub-Saharan Africa; and looks at a range of geographical contexts: non-violent, conflict and post-conflict situations. The main part of the paper reports on recent findings of extensive field-work into the use of mobile phones in 11 countries in Sub-Saharan Africa. The findings are important partly because from a welfare view, it is use rather than mere adoption that generates actual benefits to consumers. What the survey finds is that use of the mobile phone is mainly for safety-related purposes and that the countries that fare highest in terms of usage are drawn from the richest and poorest members of the sample. In explaining these results I draw heavily on the relationships and interactions between poverty, inequality and crime. For example, the dominance of Southern African countries is ascribed to their exceptionally high levels of inequality, which, in turn, are due partly to the unequal effects of resource abundance.  相似文献   

12.
Because South Africa is situated in a semi-dry region, the limited water resources are placed under increasing pressure by consumers from different sectors. Irrigation consumes more than half of the available water resources in South Africa. In the Northwest Province large volumes of water are found in dolomitic aquifers. Since 1970 irrigation from these aquifers has resulted in an exponential growth in the withdrawal of groundwater. The purpose of this study is to evaluate the effectiveness of groundwater utilization with centre-pivot irrigation in the Northwest Province, as well as to identify the most important variables that influence this effectiveness. Factor Analysis and Multiple Regression Analysis were used to establish a model with which the probable effectiveness of groundwater utilization on a specific farm can be predicted. The results show that four variables have a significant effect on the net profit margin from centre-pivot irrigation in the study area, namely: • Knowledge regarding the water capacity of the soil • Adjusting irrigation according to precipitation • The use of a yield target for fertiliser application, and • Soil characteristics The above parameters were used to develop a model with which farmers in the study area can be ranked according to the effectiveness of their water usage for centre-pivot irrigation. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

13.
Based on a systematic sample survey among the residents of two contrasting floodplain environments - the Tista floodplain (a shallow flood area) and the Ganges-Brahmaputra floodplain (a deep flood area) - this study tests a central hypothesis that the floodplain residents of Bangladesh preferred regulation of flood levels as the main flood alleviation measure. The study found that, despite significant differences in property setting, flood hazard experience and the nature of indigenous adjustments to floods between the two sample areas, an overwhelming 95% of the respondents from each area preferred regulation of flood levels within a range of 0.3 to 2.0 m. The study attempts to provide an explanation for the popularity of regulated flood levels in the context of indigenous adjustments of floodplain crops and infrastructures tonormal flood levels in Bangladesh, which coincided with the respondents' preferred range of flood levels. The study points out that the objective of the UNDP/World Bank-sponsored embankment compartmentalization projects also coincides with this goal of regulating flood levels. However, to test the physical limitations of regulating water levels between neighbouring compartments and to assess the environmental impacts of the proposed projects, the study stresses the need for initiating environmental baseline surveys on the pilot compartmentalization project, which is located on the left bank of the Brahmaputra.  相似文献   

14.
浙江嘉兴市农户宅基地退出意愿的调查与分析   总被引:1,自引:0,他引:1  
宅基地退出是农村土地整治与建设用地减量化的重要途径。针对嘉兴市农村建设用地现状,开展了农户基本情况及退出现有宅基地意愿的实地调查。分析认为,目前影响宅基地退出的主要因素是农村住房及宅基地的补偿或安置、承包地的补偿或流转、农民社会保障等问题。为有效推进农户宅基地退出,应充分考虑农民权益并予妥善处理。  相似文献   

15.
Daniel Buor 《GeoJournal》2005,61(1):89-102
The paper examines the factors that influence the utilisation of health services by women in the rural and urban areas in Ghana. The systematic sampling procedure was used to draw the sample from women aged 18 and above with diverse backgrounds from Ahafo-Ano South district, representing the rural districts and Kumasi metropolis, representing the urban districts. The research instruments used for data collection were the questionnaire and formal interviews. Multiple regression was the main tool for analysis. The research reveals that the key factors that impact significantly on the utilisation of health services by women in the Ahafo-Ano South district are, distance, income and family size (number of children) while for Kumasi metropolis they are education, distance and marital status. Whereas it is clear that distance is a common problem facing women in both rural and urban areas in Ghana in the utilisation of health services, marital status and number of children have emerged as contrasting factors influencing utilisation of health services by women in rural and urban Ghana. Recommendations to improve utilisation include the location of maternal and child health services within easy reach in the rural areas, intensification of family planning education in the rural areas, the empowerment of women through access to formal education and vocational training for income generation activities and the full implementation of the National Health Insurance Scheme (NHIS). A model of utilisation of health services by women in the rural and urban areas has emerged.  相似文献   

16.
The article evaluates household vulnerability after the 2000 flood in two poor communities of the Limpopo Province, South Africa. The study analyses the forms of vulnerability which disasters such as floods present. Using data gathered from a survey of households, the study presents the impacts, coping and adapting strategies of households after the 2000 flood. The article argues that beyond the concern over socio-economic circumstances as the major determinant of household vulnerability, the management of the disaster can serve to perpetuate vulnerability.  相似文献   

17.
Late Quaternary moraines and diamictons containing striated clasts are described from near Elliot in the Drakensberg of South Africa. An equilibrium line altitude (ELA) of 2109 m is suggested for the palaeoglacier associated with the innermost moraine. This glacier was fed by a very extensive snowblow area and the ELA may reflect the temperature–precipitation–wind ELA rather than the temperature–precipitation ELA and be considerably below the ‘regional’ ELA. Mean annual air temperatures when glaciation occurred were probably at least 10.0°C below those of the present. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

18.
2005~2007年,在河南省南召县白土岗-南河店-带发现数十个风化花岗闪长岩型超贫磁铁矿床。矿体的形态、产状、规模与花岗闪长岩体基本一致,矿石类型、成分简单,磁性铁品位2.79~13.28%,平均9.02%,矿石易采易选,在当前经济技术条件下,开采该类矿床具较好经济效益。笔者以梅子垛铁矿为例分析说明该类矿床成矿地质特征及矿石加工技术性能。  相似文献   

19.
We explore the correspondence between changing palaeoenvironments, patterns of site use, and lithic technology at the rock shelter site Klein Kliphuis (South Africa) across the interval 65–55 000 years before present. This period coincides with the termination of Marine Isotope Stage (MIS) 4, and the disappearance of an iconic late Pleistocene archaeological unit known as the Howiesons Poort. Wood charcoals indicate sufficient soil moisture around Klein Kliphuis throughout the Howiesons Poort to support diverse tree species at a time when site occupation was relatively intense. At least some fuelwood-gathering in this period may have been undertaken to support heat treatment of silcrete, which was the dominant lithology in tool production. A coherent set of changes occurs across the MIS 4/3 transition: occupational intensity declines, tracked by declining diversity of fuelwood species, an increase in the proportion of charcoals from shrubs and small flowering plants, lower prevalence of silcrete, and less heat treatment. While declining soil moisture is implied, there appears to be a significant change in behaviour relating to site usage, whereby foraging for dense fuelwoods was replaced by the construction of ‘fast fires’ that may reflect briefer visits and increased forager mobility in early MIS 3.  相似文献   

20.
A new hominid skeleton from Sterkfontein Member 2 attaches to foot bones recovered from loose blocks during the 1980s and first described in 1995. Several flowstone horizons are present above and below the skeleton and have given clear palaeomagnetic signatures. Five changes in magnetic polarity have been identified; when constrained by the available biostratigraphy, this sequence can be placed confidently between 3.22 and 3.58 Ma. Interpolation of sedimentation rates over the small intervals between reversals allows this range to be reduced to 3.30–3.33 Ma. The skeleton is thus the oldest yet discovered and is considered to belong to a species of Australopithecus other than africanus. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

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