ISSN:0035-919X    

DOI:10.1080/00359199409520301

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

In commemoration of the sesquicentenary of the birth of Sir David Gill an assessment is given of his contributions to astronomy. Gill was in charge of the Royal Observatory at the Cape of Good Hope from 1879 to 1906.

ISSN:0035-919X    

DOI:10.1080/00359199409520302

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

After three years of personal botanical exploration at the Cape, 1772–1775, Carl Peter Thunberg increased the number of known species of vascular plants from South Africa by 66%. His detailed dissertations on individual genera laid the foundations of future monographic generic studies on the Cape Flora while hisFlora Capensis(1823) was the first large scale attempt to document the Cape's botanical diversity. TheFlora Capensisenumerated some 2,776 angiosperms (32% of the species currently known from the region) and although Thunberg failed to incorporate important taxonomic work by other late 18th and early 19th century botanists, his treatise remained an important reference work until the end of the 19th century.

ISSN:0035-919X    

DOI:10.1080/00359199409520303

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Although Linnaeus, the greatest Swedish scientist of all times, did not travel outside Europe, it is known that he had a strong desire to go to South Africa, then known as the Cape. He regretted declining, in 1735, an offer by Boerhaave in Leyden to go to the Cape and to America for a period of three years. However, Linnaeus sent out his disciples on long journeys of exploration to various parts of the world, many suffering hardships from travel and tropical diseases and several dying in foreign countries. Carl Peter Thunberg was one of these apostles, indeed, the most successful. He undertook a nine-year journey to distant countries, and survived to hold the Linnaean Chair of Medicine and Botany at the University of Uppsala for 44 years. (Karsten 1939–1946, Nordenstam 1993).

ISSN:0035-919X    

DOI:10.1080/00359199409520304

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

A wider class of solutions to the nonlinear differential equation y″ + p(x)y = qm(x)/y2m−1than that given by Reid is obtained. In the process the relationships between Kummer-Liouville transformations and generalized canonical transformations and autonomous Hamiltonian systems and Lie point symmetries are uncovered.

ISSN:0035-919X    

DOI:10.1080/00359199409520305

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The effects of various land use practices on the diversity of natural biota in southern Africa are understood poorly, and have rarely been quantified. We investigated the effects of deciduous fruit farming on bird diversity in the Elgin district, Western Cape Province, South Africa. A total of 116 bird species was recorded in the district, of which 110 were recorded on the fruit farms and 30 in a nearby protected area within untransformed Mountain Fynbos. Six species were recorded only in the protected area. Fourteen species were recorded during surveys undertaken within orchards. More species, especially those favouring scrub habitats, were recorded in orchards with <0.5 ha fragments of natural biotopes than in orchards lacking such biotopes. Population densities in orchards under traditional (= heavy and routine) insecticide and fungicide spraying programmes and those in which lower intensity spraying is targeted at specific pests were similar. We suggest that the placement, size and connectedness of fragmented natural biotopes (even those infested by alien plants) within deciduous fruit farms, the addition of new biotopes (e.g. farm dams), and the presence of large (>20 ha) protected areas within the matrix of transformed habitats have complemented the pre-farming avian diversity in the Elgin district as a result of district-wide land use practices.

ISSN:0035-919X    

DOI:10.1080/00359199409520306

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0035-919X    

DOI:10.1080/00359199409520307

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The shipping of plutonium from Europe to Japan around the Cape is a contentious issue which has raised public concern that South Africans may be at risk to plutonium exposure should an accident occur: The paper describes the containers in which the plutonium (in the form of plutonium oxide, PuO2) is housed and consequences of the unlikely event of these becoming ruptured. Wind-born pollution is considered not to be a likely scenario, with the PuO2particles more likely to remain practically insoluble and sedimenting. Plutonium aqueous and environmental chemistry is briefly discussed. Some computer modelling whereby PuO2is brought into contact with seawater has been performed and the results are presented. The impact on marine organisms is discussed in terms of studies performed at marine dump sites and after the crash of a bomber carrying nuclear warheads at Thule, Greenland in 1968. Various pathways from the sea to land are considered in the light of studies done at Sellafield, a reprocessing plant in the United Kingdom. Some recent debates, such as that on the leukaemia cluster at Sellafield, in the popular scientific press are described. Plutonium biochemistry and toxicity are discussed as well as medical histories of workers exposed to plutonium.

ISSN:0035-919X    

DOI:10.1080/00359199409520308

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0035-919X    

DOI:10.1080/00359199409520309

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The climatology of storm events and rough sea conditions which poses logistical problems to ships rounding the coast of South Africa is analysed. Severe environmental conditions are contributed by “roaring 40s” southwesterly gales and swells, and enhanced by the warm Agulhas Current. The chance of a winter storm system with a pressure < 995 hPa affecting the South African south coast is 5%, the chance of gale force winds > 25 m s−1is > 1% in all seasons, and the chance of winter swells > 9 m is 1%. The mixing potential and transport pathways in the ocean and the lower atmosphere are considered, in the event of a marine accident involving radioactive or hazardous waste spilling onto the continental shelf.

ISSN:0035-919X    

DOI:10.1080/00359199409520310

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor