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1.
February 2003, Water Research Commission, Pretoria, South Africa. Ring-bound, soft cover, 200 pages. WRC Report No. TT 201/02; ISBN 978-1-86845-900-1; price R100.00 (South Africa), US$50.00 (international). Obtainable from the Water Research Commission, Private Bag X03, Gezina, Pretoria 0031, South Africa, or   相似文献   

2.
Alan C. Kemp 《Ostrich》2013,84(1-2):35-39
Kemp, A. C. 1991. Timing of laying by Greater Kestrels Fulco rupicoloides near Pretoria, South Africa. Ostrich 62: 35–39.

Laying dates for a population of individually marked Greater Kestrels Falco rupicoloides, on grass- and croplands near Pretoria, South Africa, were determined for 89 nesting attempts during 1975–1988. Laying occurred in the austral spring between 23 July and 11 November. Timing of laying was negatively correlated with rainfall of the previous summer and positively correlated with rainfall of the winter and spring preceding laying. Success in fledging young was significantly higher for clutches laid before the median laying date of 1 September and for clutches laid after seasons of above average rainfall.  相似文献   

3.
Alan C. Kemp 《Ostrich》2013,84(2-3):61-68
Kemp, A. C. 1995. Aspects of the breeding biology and behaviour of the Secretarybird Sagittarius serpentarius near Pretoria, South Africa. Ostrich 66: 61–68.

Secretarybirds in three adjacent territories were monitored from 1977 to 1988 on grass- and croplands near Pretoria, South Africa. Most observations of breeding biology and behaviour confirmed or extended previous studies. There was no correlation between pairs in occupancy of territory, productivity or development periods of young: this confirms the flexible breeding abilities which are unusual for such a large bird. Some aspects of breeding biology (egg shape and texture, watering of chicks) and behaviour (Wings open and Up-down greeting displays) may be homologous with storks and important in understanding the phylogeny and evolution of the Sagitariidae and other diurnal raptors.  相似文献   

4.
Summary

Although the emphasis of the recent National Rivers Research Initiative (now the Research Programme for the Management of Rivers) in South Africa was on river research in that country, the reality is that in southern Africa many watercourses are shared by more than one country. Therefore a central issue in integrated river basin management and development should be the recognition of the principle of international joint planning, conservation, monitoring and research.

Co-operation and a better understanding of shared waters would prevent deleterious impacts, not only in the country where they occur, but also in those downstream. With this in mind, since the early 1980s Namibia has worked on joint cross-border projects in efforts to manage and conserve her shared water bodies. These include joint river gauging exercises, biological control of Saivinia molesta in the eastern Caprivi region and, more recently, the application of a biological monitoring technique, the South African Scoring System version 4, to north-eastern perennial rivers.

The formation of the Joint Permanent Water Commission between Botswana and Namibia enabled the Departments of Water Affairs of both countries to work together on their shared rivers. The establishment of the Permanent Okavango River Basin Water Commission between Angola, Botswana and Namibia in 1994 improved this co-operation even further. Namibia and its' counterparts are thus committed to sharing information, co-ordinating research and monitoring activities and to undertaking detailed studies to improve their knowledge of these shared systems.

Such cross-border co-operation is vital for the survival of shared river systems not only as ecological entities in their own right, but also as sources of water, power and the other resources they provide, both directly and indirectly, to the human and wildlife populations that they support.  相似文献   

5.
Alan C. Kemp 《Ostrich》2013,84(3-4):220-224
Kemp, A. C. 1999. Plumage development and visual communication in the Greater Kestrel Falco rupicoloides near Pretoria, South Africa. Ostrich 70 (3&4): 220–224.

I trapped, marked, sexed and examined moult and softparts on 101 free-living Greater Kestrels Falco rupicoloides near Pretoria, South Africa, during 1975–1988.1 collected and plucked one kestrel to determine the number and mass of its feather tracts, as an index of materials invested in moult. I also examined moult on 72 museum specimens from southern Africa and observed plumage and softpart changes in four captive birds. During 1975–1979,1 made focal observations on free-living adult kestrels (males 181 h, females 262 h) and recorded monthly samples of their visual communication behaviours to the nearest minute.

Greater Kestrels can be aged for three successive plumage and softpart stages (juvenile, post-juvenile, adult). Plumage changes with potential signal effects involved only small investments at the post-juvenile and first adult moults (3.7% and 11% of total plumage mass respectively). Changes in colouration and communication behaviour correlated with relevant stages of the annual cycle, possibly to miminze conflict with territorial adults and age of first breeding. Remex and rectrix moult starts on average much later in relation to egglaying for Greater and some tropical kestrels than for some temperate species. This and other individual variation in timing may result for variations in nutritional status.  相似文献   

6.
With approximately 1000 species, Eugenia s.str. (excluding Syzygium) is one of the largest genera in the Myrtaceae. Morphological and anatomical studies concluded that two supraspecific groups (X and Y) exist in African members of Eugenia. A multigene approach was used to investigate phylogenetic/molecular relationships within southern African Eugenia, as well as representatives from elsewhere in the world. The cpDNA rpl16 intron data supported the distinctness of species groups X and Y. Little sequence divergence was found within the rpl16 intron of Eugenia. Nuclear sequence data were more variable than cpDNA and also supported the two groups. Combined data enhanced the resolution of closely related species. Species group X is related to Eugenia of the New World whereas the affinity of species group Y lies with Eugenia of the Old World. It is hypothesised that the origin of Eugenia in southern Africa is twofold. The presence of cryptic dioecy (structural androdioecy) in both groups of Eugenia in Africa is probably due to convergence. The suggestion that E. incerta is not native to Africa is supported by molecular evidence. The genus Monimiastrum is embedded within a clade with Mauritian Eugenia.We thank Danielle Florens, J. C. Sevathian and G. dArgent of the Mauritius Herbarium, Reduit, for the collection of all the material from Mauritius; Ed Biffin, CSIRO, Australia, for supplying DNA of E. reinwardtiana and Rhodamnia argentea; A. Salywon, Arizona State Univeristy, Tempe, USA for material from Florida; Timothy Lowrey, University of New Mexico, Albuquerque, USA, for material from Madagascar; and A. Urban, Stefan Neser (ARC, Pretoria) and J. H. Pedrosa-Macedo (Forest Research Foundation, Federal University of Parana, Curitiba, Brazil) for the material from Brazil. The authors are indebted to the National Research Foundation (South Africa) and the University of Pretoria for financial assistance.  相似文献   

7.
Book reviews     
Patterns of thought in Africa and the West: Essays on magic, religion and science , by Robin Horton. Cambridge University Press, Cambridge, 1997. xi, 471pp., figures, notes, bibliography, index. ISBN 0–521–36926–6 (paperback).

Women's experiences with HIV/AIDS: An international perspective , edited by Lynellyn D. Long and E. Maxine Ankrah. Columbia University Press, New York, 1996. x, 426pp., tables, references, notes on contributors, index. ISBN 0–231–10605‐X (paperback).

A healing place: Indigenous visions for personal empowerment and community recovery , by Kayleen M. Hazelhurst. Central Queensland University Press, Rockhampton, 1996. xiii, 274pp., notes, illustrations, references. ISBN 0–908140–87–8 (paperback).

Reading the skin: Adornment, display and society among the Wahgi , by Michael O'Hanlon. Crawford House Press, Bathurst, 1989. 139pp., map, photographs, orthography and kinship terms, glossary, notes, bibliography, index. ISBN 1–86333–003–8 (hardback).

Paradise: Portraying the New Guinea Highlands , by Michael O'Hanlon. Crawford House Press, Bathurst, 1993. 99pp., maps, photographs, notes, bibliography, index. ISBN 1–86333–078‐X (paperback).

To sing with pigs is human: The concept of person in Papua New Guinea , by Jane C. Goodale. University of Washington Press, Seattle, 1995. xvi, 269pp., map, tables, figure, musical scores, photographs, bibliography, index. ISBN 0–295–94736–2 (paperback).

Resplendent sites, discordant voices: Sri Lankans and international tourism , by Malcolm Crick. Harwood Academic Publishers, Chur, 1994. x, 237pp., maps, tables, photographs, bibliography, index. ISBN 3–7186–5564–0 (hardback).

Impasse of the angels: Scenes from a Moroccan space of memory , by Stefania Pandolfo. University of Chicago Press, Chicago, 1997. xi, 389pp., photograph, notes, index. ISBN 0–226–64532–0 (paperback).

Mal'uocchiu: Ambiguity, evil eye, and the language of distress , by Sam Migliore. University of Toronto Press, Toronto, 1997. xiv, 159pp., tables, figures, glossary, notes, bibliography, index. ISBN 0–8020–7922–9 (paperback).

Satmar: Two generations of an urban island: The life, thought and culture of an Hasidic Jewish community in America , by Israel Rubin. Peter Lang, New York, 1997. xii, 341pp., tables, figures, notes, index. ISBN 0–8204–0759–3 (hardback).

UFO crash at Roswell: The genesis of a modern myth , by Benson Saler, Charles A. Ziegler and Charles B. Moore. Smithsonian Institution Press, Washington DC, 1997. xii, 198pp., maps, tables, figures, appendices, notes, bibliography, index. ISBN 1–56098–751–0 (hardback).  相似文献   


8.
Capsule: Supplementary feeding stations provide a useful conservation benefit for vultures, without disrupting their natural movement ecology.

Aims: To understand the effects of providing supplementary food on the movement ecology of vultures.

Methods: We used Global Positioning System tracking devices to monitor the movements of 28 Cape Vultures Gyps coprotheres using feeding stations in South Africa. We calculated home range values and then performed a habitat selection analysis.

Results: We show that aside from roost sites, vulture feeding stations are the most important environmental variable that explains vulture movements. However, we found that the birds ranged over areas without supplementary food and their mean home range values were comparable to those measured before the inception of feeding stations.

Conclusion: Our findings suggest that the use of supplementary feeding sites did not significantly impact on the natural foraging behaviour of the species.  相似文献   


9.
This study investigates lightning density in relation to burning frequency in five South African biomes. Data from automatic lightning flash counters distributed throughout South Africa are used to estimate the range and mean values of annual lightning ground-strike density in each biome. The lowest average lightning frequencies were recorded in the karoo and fynbos biomes, while the highest values were obtained in the sour and inland mountain divisions of the grassland biome, with intermediate values computed for the savanna-woodland and forest biomes. These results were compared with published findings on the effects of different burning frequencies on plant communities in each biome. In general, plant communities occurring in areas experiencing the highest annual lightning densities (e.g., sour and mixed grassland, and moist savanna-woodland) tolerate and require more frequent burning than those typical of areas subject to lower lightning densities (e.g., fynbos, forest, sweet grassland, and arid savanna-woodland). These findings suggest that the constituent plant populations in each biome have adapted to burning frequency according to the local probability of ignition by lightning in the areas they inhabit, and that present day responses of plant communities to burning reflect their ancestral exposure to fire in the course of their evolutionary development under pre-existing, natural fire regimes.Research sponsered by the South African Council for Scientific and Industrial Research. We thank the Director, National Electrical Engineering Research Institute (NEERI), Pretoria, South Africa, and H. Kröninger, Lightning Research Division, NEERI, for providing data on lightning ground-strike densities and coordinates and elevations for counters in South Africa. We thank Drs J. H. Bock and M. T. Mentis for commenting on an early draft of this paper.  相似文献   

10.
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12.
The Systemwide Initiative on Malaria and Agriculture (SIMA) is an initiative of international agricultural research centers to promote research and capacity building on the links between malaria and agriculture and to validate innovative interventions that would strengthen and complement existing malaria-control strategies in clearly defined settings. Knowledge regarding the nature and dynamics of agroecosystems is particularly needed for the purpose of developing appropriate farmer-managed preventive measures against malaria. SIMA research aims to make use of new and existing information on biomedical and socioeconomic determinants of malaria risks in formulating and evaluating the feasibility of integrated strategies. The initiative is especially interested and proactive in promoting and facilitating transdisciplinary and participatory research in relation to malaria. The convening institute for SIMA is the International Water Management Institute at its Africa Regional Office in Pretoria, South Africa. This article outlines SIMAs objectives and scope of activities and also highlights achievements, challenges, and opportunities for future collaboration.  相似文献   

13.
Three new species of Crenitis Bedel, 1881 are described from South Africa; C. castellus sp.n. and C. rupestris sp. n. from the KwaZulu-Natal Drakensberg, and C. quagga sp.n. from the Western Cape Province. All three new species were found in madicolous habitats, which appear to be characteristic for a number of species of the genus. A revised key to African species of Crenitis is included.

http://zoobank.org/urn:lsid:zoobank.org:pub:18BE876C-46CB-4AD5-9BB0-EA6F8D711F09  相似文献   


14.
The genus Cheimacheramus Barnard, 1934 Barnard, K.H. (1934), ‘South African Caddis-Flies (Trichoptera)’, Transactions of the Royal Society of South Africa, 21, 291394.[Taylor &; Francis Online] [Google Scholar] included only three species, one from South Africa and two from Madagascar. Four new Malagasy species are described herein: Cheimacheramus akandi sp. n., Cheimacheramus barnardi sp. n. and Cheimacheramus anjojorobensis sp. n. from the Anjojorobe Forest, Cheimacheramus madecassus sp. n. from the Lakato Forest and the Marojejy National Park. Diagnostic characters of the genus and species are discussed and illustrated. In Madagascar, these discoveries confirm the localization of the genus within the eastern evergreen forests.

http://zoobank.org/urn:zoobank.org:pub:79472077-04E9-42FA-B55B-9EE291556E60  相似文献   

15.
The tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) represents a global threat to commercial tomato (Solanum lycopersicum L.) production, both in open field and greenhouse. Native to South America, it spread over the Mediterranean Basin, Europe, Africa and part of Asia in only 12 years, and currently it is reported in over 80 countries. Biological control is one of the options for its control and a large number of natural enemies has been reported in association with the pest, both in the areas of origin and of introduction. The egg parasitoid Trichogramma pretiosum, in South America, and the mirid predators Macrolophus pygmaeus and Nesidiocoris tenuis, in Europe and the Mediterranean basin, are used as commercial biocontrol agents. Even if several natural enemies might be promising candidates for biocontrol, their potential role in quantitative pest reduction has been seldom established under practical tomato production conditions.

Since climatic suitability indices predict a high probability for continued invasion by T. absoluta, mainly in China and the USA, there is an urgent need for new control options. In order to minimise the use of broad spectrum insecticides, biocontrol techniques should be considered. As tomato is produced seasonally, augmentative biocontrol seems to be the most effective control option, but pest reduction might be optimised by adding conservation biocontrol, and by combining biocontrol within IPM programmes.

Here, an overview of predators and parasitoids of T. absoluta in South American and Euro-Mediterranean regions, and their biological control efficacy under laboratory, semi-field and field conditions is provided.  相似文献   


16.
Introduction: Although the association between periodontal disease (PD) and adverse pregnancy outcomes has gained recognition amongst antenatal healthcare workers, not much has changed in practice to address it. This prospective study tested the hypothesis that BANA (N-benzoyl-DL-arginine-2-naphthylamide), a diagnostic test for PD, may inform obstetricians and other antenatal healthcare practitioners, of the risk of adverse pregnancy outcomes in mothers attending antenatal clinics.

Methods: At first visit, the presence of suspected periodontopathogens was assessed by BANA testing of dental plaque from 443 mothers attending antenatal clinics in KwaZulu-Natal, South Africa and an association later sought with pregnancy outcomes. The accuracy of BANA to predict adverse pregnancy outcomes was evaluated by the calculation of likelihood ratios. The study complied with the Declaration of Helsinki.

Results: Significant differences were found between pregnancy outcomes of BANA-negative and BANA-positive mothers (p?<?0.0001). BANA showed sensitivity and negative predictive values of 87% and 91%; 75% and 78%; 87% and 94% in detecting low birth weight, preterm delivery, and preterm low birth weight delivery respectively.

Conclusion: This study confirms that BANA may indicate the need for periodontal therapy to reduce the risk of adverse pregnancy outcomes and could form part of the routine antenatal examination.  相似文献   


17.

Background

Incidence rates in the FEM-PrEP and VOICE trials demonstrate that women from diverse sub-Saharan African communities continue to be at substantial HIV risk.

Objective

To describe and compare the sexual risk context of the study population from two FEM-PrEP trial sites–Bondo, Kenya, and Pretoria, South Africa.

Methods

At baseline we collected information about demographics, sexual behaviors, and partnership beliefs through quantitative questionnaires with all participants (Bondo, n = 720; Pretoria, n = 750). To explore the sexual risk context, we also conducted qualitative, semi-structured interviews with HIV-negative participants randomly selected at several time points (Bondo, n = 111; Pretoria, n = 69).

Results

Demographics, sexual behavior, and partnership beliefs varied significantly between the sites. Bondo participants were generally older, had fewer years of schooling, and were more likely to be employed and married compared to Pretoria participants. Bondo participants were more likely to report multiple partners and not knowing whether their partner had HIV than Pretoria participants. A significantly higher percentage of Bondo participants reported engaging in sex without a condom with their primary and other partners compared to Pretoria participants. We found a borderline association between participants who reported not using condoms in the 4 weeks prior to baseline and lower risk of HIV infection, and no association between having more than one sexual partner at baseline and HIV infection.

Discussion

Despite significantly different demographics, sexual behaviors, and partnership beliefs, many women in the FEM-PrEP trial were at risk of acquiring HIV as demonstrated by the sites’ high HIV incidence. Though gender dynamics differed between the populations, they appear to play a critical role in women’s sexual practices. The findings highlight different ways women from diverse contexts may be at-risk for HIV and the importance of providing HIV prevention options that are both effective and feasible given personal and social circumstances.  相似文献   

18.
Capsule: Red-footed Falcons Falco vespertinus migrating from northern Kazakhstan proceed west before heading south to Africa; their northbound travel follows a different route with passage close to shooting hotspots in the Mediterranean.

Aim: To use tracking and ringing data to document for the first time the migration of globally threatened Red-footed Falcons from northern Kazakhstan.

Methods: Light-level geolocators were deployed on breeding adults in Kazakhstan and recovered one year later. Ringing and observational data from more than 100 years of Russian-language and other literature were summarized and mapped alongside the geolocator data.

Results: Geolocator, ringing and observational data together demonstrate that Red-footed Falcons from northern Kazakhstan have a clockwise loop migration that begins with a long and unusual westward trek around eastern Europe’s large inland seas before continuing to extreme southern Africa. Return migration is farther west and requires crossing two major migratory barriers: the Sahara and the Mediterranean.

Conclusion: The loop migration we describe requires an extensive longitudinal movement, exposes central Asian Red-footed Falcons to multiple desert, mountain and marine crossings, and, at outbound and return Mediterranean bottlenecks, crosses sites where raptor shooting is common.  相似文献   


19.
The paper describes the thornbush invasion (bush encroachment) found in the savanna at Olifants Drift in eastern Botswana. Overgrazing by cattle is responsible for the opening up of the grass sward and has enabled woody species to establish. A quantification of this process between 1950 and 1975 in an area of ca. 100 km2 is given in terms of plant density as well as aboveground biomass. The loss of herbaceous biomass which generally accompanies bush encroachment and the possibilities for pasture restoration are mentioned.Species nomenclature follows the Flora of Southern Africa and the system in use at the herbarium of the Botanical Research Institute at Pretoria, South Africa.  相似文献   

20.
Background: Predictive value of cardiac tropnins (cTns) in stable coronary artery disease (SCAD) has not been fully investigated.

Methods: We performed a meta-analysis to evaluate the dose–response relationship between serum detectable/rising cTns and adverse clinical outcomes, including all-cause mortality, cardiovascular (CV) mortality, myocardial infarction (MI), heart failure (HF) or major adverse cardiovascular events (MACEs) in SCAD.

Results: Sixteen studies involved 34,854 subjects were included. Compared with patients with negative/undetectable cTns, those with rising/detectable cTns were associated with increased risk of all-cause mortality, CV mortality, MI, HF and MACEs [the hazard ratio (HR) was 1.83 (95% confidence interval (CI) 1.61–2.08), 2.11 (1.80–2.48), 1.43 (1.26–1.62), 2.36 (1.97–2.83) and 1.99 (1.57–2.53), respectively]. Dose–response analysis have revealed that per 1-SD increment of cTnT was associated with increased risk of all-cause mortality, CV mortality, MI, HF and MACEs [the HR was 1.78 (1.20–2.63), 1.62 (1.41–1.85), 1.26 (1.12–1.42), 1.78 (1.17–2.69) and 1.26 (1.00–1.59), respectively].

Conclusion: Rising/detectable cTns was associated with increased risk of all-cause mortality, CV mortality, MI, HF and MACEs in SCAD in a dose–response manner.  相似文献   


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