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1.
纵观南非、埃及的水资源管理   总被引:1,自引:0,他引:1  
林兴潮 《地下水》2007,29(6):1-6
南非地处南半球,是非洲大陆最大的国家,地处非洲大陆南端.埃及跨亚、非两洲,大部分位于非洲东北部.两国都属资源性缺水国家,两国从各自的国情出发,实行着切合实际的、严格的水资源管理政策.我国和南非、埃及有着人口多、耕地资源少、水资源紧张等相同特点,两国在水资源管理、保护和节约等方面的诸多成功经验和做法值得我国学习和借鉴.  相似文献   

2.
P. J. Stickler 《GeoJournal》1990,22(3):329-333
Many large Black settlements are downgraded or made invisible on maps of South Africa. This form of subjective generalisation gives a false prominence to small White towns. A more realistic map of the major settlements in South Africa is presented. The problems associated with mapping of Black settlements are discussed. These include the lack of census data, absence of official recognition of places, difficulties of place naming and the lack of functional imcomparability with other places.  相似文献   

3.
王丰翔 《地质与勘探》2021,57(6):1229-1242
铂族元素(Platinum group elements,PGEs)作为地壳最稀缺的一类金属元素,是重要的战略性矿产资源,与金一样,具有经济和科技双重的功能。非洲铂族金属矿产资源丰富且高度集中,占世界资源量> 80 %,主要集中在南非和津巴布韦。本文在前人研究基础上,对非洲PGEs矿床主要成矿类型、时空分布特点和开发利用现状进行了总结,研究认为:(1)非洲大型-超大型PGEs矿床成因类型主要为岩浆型,在时空上与世界级铁质-镁铁质大火成岩省(南非布什维尔德和津巴布韦大岩墙)密切相关,可细化分为脉状铜镍硫化物型、整合接触型铜镍硫化物型、脉状铬铁矿型和钒钛磁铁矿型。依据区域构造演化及其所产出的矿化特征,认为以铁质-镁铁质岩有关的岩浆型矿床仍具有较大的找矿潜力。(2)非洲铂族金属矿产勘查开发程度相对较高,近十年是全球勘查资金投入最多的地区,同时也是世界第一大Pt生产地和第二大Pd生产地。从事勘查开发的主要为世界顶级PGEs矿业寡头。(3)非洲是全球一次性铂族金属矿产品主要供应国,主要出口至美国、日本、中国、德国和英国。加强与南非、津巴布韦等国家之间的合作,保障PGEs资源供应的安全对我国尤为重要。  相似文献   

4.
A first-order seismotectonic model was created for South Africa. This was done using four logical steps: geoscientific data collection, characterisation, assimilation and zonation. Through the definition of subunits of concentrations of earthquake foci and large neotectonic and structural domains, seismotectonic structures, systems and domains were created. Relatively larger controls of seismicity exist between the Great Escarpment and the coast. In the south, this region is characterised by large aeromagnetic anomalies and large EW trending faults. In the west, it is characterised by the NW–SE trending Wegener stress anomaly, radial-trending dykes and earthquake clusters. In the east, it is characterised by a large neotectonic domain where several large historical earthquakes occurred. In the centre of South Africa, several clusters of earthquake activity are found, often related to mining activity. Further north, seismicity is related to both mining activity and neotectonic deformation. This work contributes to the development of a seismotectonic model for South Africa by (1) bringing together, digitally, several data sets in a common GIS platform (geology, geophysics, stress, seismicity, neotectonics, topography, crustal and mantle structure and anisotropy), (2) understanding the significance of data sets for seismotectonic zonation and limitations thereof and (3) obtaining a reasonable regional model for use in seismic hazard assessments.  相似文献   

5.
This paper assesses the possibility of sustainable agriculture in South Africa in the context of recent policy initiatives. The new environmental strategy for agriculture represents a significant break with policy initiatives developed during apartheid. The likelihood of sustainable farming practices being adopted in South Africa will, however, face at least three obstacles. These are the integrated structure of industrial farming, the concern over yields, and current political and economic changes in South African agriculture. It is argued that sustainable techniques are unlikely to develop in the large scale farming sector in the near future. If the considerable research and extension resources of the state are reoriented quickly enough, sustainable farming methods can be embraced by an emerging class of black commercial farmers.  相似文献   

6.
Water and water related matters are important issues in water scarce countries like the Republic of South Africa. This is especially true for the agricultural sector that relies heavily on the availability of water for irrigation to ensure a secure food supply. In South Africa, present day irrigation projects rely on government subsidies and are usually large undertakings beyond the reach of individuals or small communities. The sustainability of such large irrigation projects is still a matter of debate. A 100 years ago a different set of rules applied. Irrigation could only be achieved by hand-dug furrows that supplied water in relatively small quantities to small farming communities. This paper investigated such a small community, the Leeukloof farming community in the Western Cape Province of the Republic of South Africa. For the past 93 years this community has maintained a furrow that supplies water not only to farms bordering the Perdeberg River, which supplies the furrow with water, but also to farms not bordering the river. The authors try to reconstruct the changes in agricultural practices brought about by the furrow, methods of water extraction during each phase, as well as the development and role of the furrow system. The perception by the community of the necessity of this method of water extraction from the river system is also investigated. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

7.
This paper presents a critical engagement with current initiatives for ethically-labeled goods in South Africa, thus offering an intervention in a literature on ethical consumption that has previously prioritized the global North. Through an interview-based methodology supported by focus groups in the Western Cape, the paper attends specifically to the strategies shaping recent forms of ethical consumption in South Africa on the part of business and civil society. Campaigns and strategies associated with three of the most prominent ethical labeling initiatives in South Africa—Proudly South African, Fairtrade Label South Africa and the Southern African Sustainable Seafood Initiative (SASSI)—are evaluated. Barnett et al.’s (2011: 90) notion of “mobilizing the ethical consumer” is brought into conversation with ethical consumption literature on local embeddedness in order to assess the ways in which the organizations responsible for these initiatives combine globalizing business and political networks of responsibility with local institutions and values in South Africa. The role played by the discursive construction of a growing South African ‘middle class’ is also acknowledged as part of the process of encouraging ethical consumption on the part of these actors. In conclusion, it is suggested that understanding ethical consumption in South Africa, as elsewhere, requires sensitivity to both transnational networks of globalizing responsibility and localized expressions of ethical consumption.  相似文献   

8.
非洲锰矿床成矿规律、开发利用与勘查建议   总被引:1,自引:0,他引:1  
栾卓然 《地质与勘探》2021,57(6):1216-1228
锰矿是我国重要的战略矿产资源,需求量不断增长,长期依赖国外资源保障供需关系。本文总结分析了非洲锰矿资源的特点、矿床类型与成矿规律等地质特征与勘查开发利用及贸易现状。分析表明:非洲是全球探明锰矿储量和资源量最多的地区,具有分布集中,规模大、品位高、杂质少的特点;锰矿床类型主要有条带状含铁建造(BIF)型、海相沉积型、海相火山-沉积型、陆相(湖相三角洲)沉积型、岩浆热液型等五大类,普遍遭受表生风化淋滤(溶蚀)作用改造;主要分布在卡普瓦尔克拉通、刚果克拉通西北部的加蓬地块和西非克拉通南缘的马恩-莱奥地盾中;成矿时代主要集中于前寒武纪,尤其是2.2~2.0Ga;非洲锰矿资源的勘查开发程度较高,其中南非是非洲锰矿勘查程度最高的国家,中非、北非国家的勘查开发程度较低;南非是全球最大的锰矿石生产国和锰矿产品出口国,目前占全球出口量的68.19%以上,我国是非洲锰矿产的最大出口地,占其出口总量的70.19%。建议:我国在非洲的勘查应重点关注非洲中部的条带状含铁建造(BIF)型锰矿和海相火山-沉积型锰矿;在非洲已有的中企基础上,组建大型的集团公司,建立多元的锰矿资源供应体系。  相似文献   

9.
One hundred and thirty-six species, representing 67 genera have been recorded from the late Jurassic-Maastrichtian marine sediments of South Africa. The faunas show a major dichotomy across a regionally-developed late Cenomanian-early Coniacian hiatus with the Portlandian-Cenomanian Cytheruridae/Progonocytheridae/Schizocytheridae dominated faunas being replaced in the Coniacian by Trachyleberididae/Brachycytheridae/Schizocytheridae dominated faunas. Comparison with other Gondwanide localities shows that the two South African basins from which ostracods have been described (Outeniqua and Natal/Zululand) formed part of a Callovian-Cenomanian South Gondwana ostracod province that stretched from the Neuquen Basin of Argentina to Madagascar/Tanzania/Kutch and west Australia. The most characteristic and cosmopolitan forms within this province belong to the Majungaella/Amicytheridea/Progonocythere group, along with Arculicythere in the Aptian-Cenomanian.In Tanzania, (the only locality of the old South Gondwana province where the succession is complete) these assemblages are replaced in the Turonian by the influx of Brachycythere, and Cythereis and various other trachyleberids. Changes of a similar nature are seen whenever marine sedimentation resumed after the local “mid” Cretaceous hiatus (South Africa, India, Argentina). Argentina differs in not having Brachycythere, whose rapid appearance in the West Indian Ocean basin soon after its earliest record in Brazil, is attributed to the destruction of the barrier at the eastern end of the Walvis Ridge/Rio Grande Rise in late Cenomanian or early Turonian times. Despite this common element with Brazil and West Africa, the South African Coniacian to Maastrichtian faunas are closer to those of Tanzania and Australia than they are to either Argentina or Brazil/West Africa. In Zululand they show evidence of a steady increase in water depth, leading to the establishment of progressively more diverse cytheracean populations, with a particularly large increase across the Santonian/Campanian boundary.  相似文献   

10.
The movement of Antarctica with respect to South America has a number of implications for paleocirculation as well as for the reconstructions of Gondwanaland. Recent papers on the Southwest Indian Ridge have published new or revised poles of opening for Africa and Antarctica which can be combined with the poles of opening between South America and Africa to give resultant motions between South America and Antarctica.The first indication of a complete closure between South America and the Antarctic Peninsula is at anomaly 28 time (64 Ma) as the two continents are now configured. Between anomaly 28 time (64 Ma) and anomaly M0 time (119 Ma) the amount of closure does not change greatly, and the small computed overlap can be explained by minor uncertainties in the rotation poles used for the reconstructions or some slight extension between East and West Antarctica. By 135 Ma some rotation or translation of the Antarctic Peninsula with respect to East Antarctica must be postulated in addition to any presumed extension between East and West Antarctica in order to avoid an overlap of South America with the Antarctic Peninsula.Having determined what we feel to be a viable reconstruction of Western Gondwanaland and holding South America fixed, we rotated Africa and Antarctica, with respect to South America, for eight different times during the past. Africa moved away from South America in a more or less consistent manner throughout the time period, closure to present, while Antarctica moved away from Africa in a consistent manner only between 160 Ma and 64 Ma. At 64 Ma its motion changed abruptly: it slowed its north-south motion with respect to Africa and began slow east-west extension with respect to South America. This change supports the hypothesis that a major reorganization of the triple junction between Africa, Antarctica and South America occurred between 60 and 65 Ma. The triple junction changed from ridge-ridge-ridge to ridge-fault-fault at the time of the major westward jump of the Mid-Atlantic Ridge just south of the Falkland-Agulhas Fracture Zone.The Mesozoic opening of the Somali Basin moved Madagascar from its presumed original position with Africa in Gondwanaland. The closure of Sri Lanka with India produces a unique fit for India and Sri Lanka with respect to Africa, Madagascar and Antarctica. This fit juxtaposes geological localities in Southeast India against similar localities in Enderhy Land. East Antarctica. The late Jurassic opening in the Somali Basin is tied to opening of the same age in the Mozambique Basin. Since this late Jurassic movement represents the initial break-up of Gondwanaland, it is assumed that similar movement must have occurred in what is now the western Weddell Sea and may also explain the opening evidenced by the Rocas Verdes region of southern South America.  相似文献   

11.
Volunteer tourism as a subset of alternative tourism is the focus of analysis. This paper contributes to the limited writings on volunteer tourism by investigating the activities in South Africa of Habitat for Humanity, a grassroots ecumenical Christian organization that works in partnership with communities to eliminate poverty through the provision of shelter. A profile of the volunteer tourist and of their tourism experience in South Africa is presented which is based largely upon the return of 123 questionnaires from volunteer tourists in South Africa working with the local branch of Habitat for Humanity. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

12.
Grazing and fire are major factors influencing the savanna ecosystems of Southern Africa. In both grazing and conservation areas overgrazing is an important reason for degradation of vegetation and soil. Insufficient fire management can cause a change in the species composition and may influence the soil negatively. For adequate planning purposes the knowledge of available biomass is indispensable. High-resolution satellite systems can provide such knowledge on a large scale. Three study areas in Southern Africa contributed to a first survey. Gutu District is situated in Zimbabwe. In its Communal Lands a high population density leads to severe degradation of vegetation and soil. The South African test sites are located in Kruger National Park and Madikwe Game Reserve. Therefore a wide ecological range from highly degraded to slightly disturbed savanna ecosystems is included. Satellite images of both Landsat-5 (TM) and Landsat-7 (ETM+) were applied. After cross-calibration of the two different satellite systems, indices applied to radiance and reflectance showed significant correlations with ground truth data of grass and other foliage biomass. Including new data from Hluhluwe National Park (South Africa) into the regression models improved the results, indicating that a regional model for savanna ecosystems in Southern Africa could be found. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

13.
During the latest Cretaceous, distinct dinosaur faunas were found in Laurasia and Gondwana. Tyrannosaurids, hadrosaurids, and ceratopsians dominated in North America and Asia, while abelisaurids and titanosaurians dominated in South America, India, and Madagascar. Little is known about dinosaur faunas from the latest Cretaceous of Africa, however. Here, a new abelisaurid theropod, Chenanisaurus barbaricus, is described from the upper Maastrichtian phosphates of the Ouled Abdoun Basin in Morocco, North Africa on the basis of a partial dentary and isolated teeth. Chenanisaurus is both one of the largest abelisaurids, and one of the youngest known African dinosaurs. Along with previously reported titanosaurian remains, Chenanisaurus documents the persistence of a classic Gondwanan abelisaurid-titanosaurian fauna in mainland Africa until just prior to the end-Cretaceous mass extinction. The animal is unusual both in terms of its large size and the unusually short and robust jaw. Although it resembles South American carnotaurines in having a deep, bowed mandible, phylogenetic analysis suggests that Chenanisaurus may represent a lineage of abelisaurids that is distinct from those previously described from the latest Cretaceous of South America, Indo-Madagascar, and Europe, consistent with the hypothesis that the fragmentation of Gondwana led to the evolution of endemic dinosaur faunas during the Late Cretaceous.  相似文献   

14.
Groundwater/surface-water interaction is receiving increasing focus in Africa due to its importance to ecologic systems and sustainability. In South Africa??s 1998 National Water Act (NWA), water-use licenses, including groundwater, are granted only after defining the Reserve, the amount of water needed to supply basic human needs and preserve some ecological integrity. Accurate quantification of groundwater contributions to ecosystems for successful implementation of the NWA proves challenging; many of South Africa??s aquifers are in heterogeneous and anisotropic fractured-rock settings. This paper reviews the current conceptualizations and investigative approaches regarding groundwater/surface-water interactions in the context of South African policies. Some selected pitfall experiences are emphasized. The most common approach in South Africa is estimation of average annual fluxes at the scale of fourth-order catchments (??500 km2) with baseflow separation techniques and then subtracting the groundwater discharge rate from the recharge rate. This approach might be a good start, but it ignores spatial and temporal variability, potentially missing local impacts associated with production-well placement. As South Africa??s NWA has already been emulated in many countries including Zambia, Zimbabwe and Kenya, the successes and failures of the South African experience dealing with the groundwater/surface-water interaction will be analyzed to guide future policy directions.  相似文献   

15.
Militarisation in South Africa is examined through a study of the development, organization and geography of military production. The rise of Armscor as a significant military-industrial enterprise is disclosed at the heart of the post-1960 growth of armaments production in South Africa. Despite intensifying arms embargoes, military industrialization in South Africa has attained a degree of self-sufficiency. Military production is analysed as a powerful implicit spatial policy shaping the South African space economy favouring in particular the development of the core metropolitan areas, most importantly the Johannesburg-Pretoria axis.  相似文献   

16.
South and southern Africa are currently facing a major skills shortage in the applied earth sciences, particularly in the minerals industry and in the environmental field. This paper offers outlines of course curricula, developed in South Africa, which are designed to meet these needs.It is argued that insufficient time is devoted to applied geology in degree courses in South Africa and that appropriate specialisations should be introduced into the third and fourth years of Earth Science degrees. More detailed specialisation should be offered at master's level. Examples of such courses currently run in South Africa are cited.The important contribution of the earth sciences to contemporary environmental issues is stressed and the need for environmental geologists emphasised. It is argued that the huge amount of information essential to environmental geology requires postgraduate level teaching of this subject. An example of such a master's level course is taken from a course planned at the University of the Witwatersrand.Courses similar to those being developed in southern Africa need to be developed in other African regions.  相似文献   

17.
It is widely held that the large majority of African countries are too small in terms of population and purchasing power to allow meaningful and rapid economic development to take place within the constraints of their domestic economies. Sub-regional groupings of states are called for in order to overcome the drawbacks of small size. Many attempt at establishing larger economic unions in Africa have failed. Particular interest therefore attaches to the southern African sub-region where South Africa, as the only industrial power south of the Sahara, functions as a powerhouse for neighbouring as well as more distant economies. The article provides a factual sketch of existing economic ties (infrastructure, trade, labour, tourism, finance and technology). Attention is paid to South Africa's efforts to create a constellation of states, and also to to the counter-measures of nine neighbouring states.  相似文献   

18.
Absolute radiometric data obtained recently in Upper Paleozoic basins of South America and Southern Africa are available to constrain the age of some palynological biozones defined in the Western Gondwana. Some dates obtained from Argentina coincide with southern Africa's and are useful to constrain the palynological associations. In this way, the Permian Argentinian LueckisporitesWeylandites (LW) Biozone is compared with the Lueckisporites virkkiae Biozone of Brazil and Zone 3 of South Africa. On the other hand, the palynofloras from Dwyka (South Africa) are comparable with Argentinian and Brazilian associations recovered near the Carboniferous–Permian boundary. Tuffaceous intervals of the Dwyka Group in South Africa suggest the beginning of that sequence at 307 Ma reaching the 290 Ma at the top. The available palynological, paleoenvironmental and radiometric data from these three western Gondwanan areas are analyzed and compared.  相似文献   

19.
Dimensions of drought: South African case studies   总被引:1,自引:0,他引:1  
The recent drought in southern Africa has underscored the need for detailed analysis of the phenomenon. While geographers have researched the causes and impacts of drought in many African contexts, South Africa and in particular its Bantustans have not received sufficient similar attention. This paper outlines firstly the dimensions of drought in South Africa, including the biophysical and socio-economic factors. Issues such as land-use management, drought planning and relief are interrogated in the South African context. The final section of the paper highlights these debates with specific reference to case studies of past and present drought initiatives in South Africa.  相似文献   

20.
Early Cretaceous intracontinental movements within Africa and/or South America, to account for misfit problem in the pre-drift reconstruction of Western Gondwana, have been tested using palaeomagnetic poles from both continents. Each continent has been considered as comprising separate subplates according to the boundaries proposed by Pindell and Dewey (1982) and Curie (1983): i.e., northern Africa ( ), southern Africa ( ), northern South America (nsa) and southern South America ( ). Visual and statistical distribution of Late Permian to Jurassic poles from the African subplates indicate two distinct groups before rotating relative to , while after the rotation they become indistinguishable. The distribution and sparsity of data from South America limit the study in this continent as the data are statistically indistinguishable before and after rotation of with respect to . When the test is extended to the reconstruction of Western Gondwana, the tightest grouping of the poles occurs when an intracontinental movement is assumed within Africa. This suggests that the misfit between the two continents is probably due to intracontinental deformation within Africa and not in South America. If confirmed, this may have profound implications in the kinematics of the processes related to the opening of the South and Central Atlantic Oceans and also the origin of the West African Rift System.  相似文献   

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