ISSN:0035-919X    

DOI:10.1080/00359198009520560

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

Transects across six kelp beds located between Cape Agulhas and Saldanha Bay are surveyed and the fauna and flora quantified in terms of energy units. Numerical analysis and information statistic tests are employed to identify areas of similarity and their characteristic species. When data from all the transects are pooled and similarly tested there is a separation of plant-dominated inshore zones from offshore stations, which are densely populated by animals. The more southerly transects tend to have higher overall standing crops of kelp—a feature which can be attributed to the greater water clarity in this area. Both mussels and rock lobsters show the reverse trend, being largely replaced by a sponge-dominated community in the south. Calculations of the plant to animal ratios at each site average only 1,27:1, suggesting that the fauna relies largely on nutritional sources other than attached algae. Standing crop figures are used to calculate the total tonnage of kelp between Cape Point and Saldanha Bay and its annual production of detritus. Standing crop figures for each transect and energy content conversion tables are listed as appendices.

ISSN:0035-919X    

DOI:10.1080/00359198009520561

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

Some early voyages off the east coast of South Africa are reviewed to highlight the discovery of the Agulhas Current, and the progress towards modern understanding of the circulation system is illustrated by a series of charts. It is shown that the main elements of the Agulhas Current system were in fact known by the early nineteenth century.

ISSN:0035-919X    

DOI:10.1080/00359198009520562

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

Intertidal macrofauna on high energy beaches in the East Cape occurs in two zones: a lower zone dominated byBullia rhodostoma, Donax sordidusand Gastrosaccus psammodytes; a midlit-toral zone starting about 0,9 m above extreme low water of spring tides and extending to about 1,9 m above ELWS is wetted on every tide and is dominated byDonax serra, with isopods also present. There is no upper zone or subterrestrial fringe, probably due to the absence of a distinct drift line. Meiofaunal distribution has been divided into four strata in the sediment: a dry sand stratum in the upper sediment near the top of the shore is wetted only at high tide and its meiofauna is predominantly nematodes; a moist sand stratum underlies the dry sand down to the permanent water table and here a rich and diverse meiofauna, usually dominated by crustaceans, occurs; a water table stratum at and below the permanent water table has lowered oxygen tensions and moderate meiofauna numbers dominated by nematodes and crustaceans; a low oxygen stratum underlies the water table stratum and here low numbers of meiofauna, predominantly nematodes, occur. Factors influencing these zones and strata are discussed and the conditions on other beaches are contrasted with those studied here.

ISSN:0035-919X    

DOI:10.1080/00359198009520563

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

The identification ofMusculus virgiliaeBarnard has been frequently confused with bothArcuatula capensis(Krauss) andBrachidontes variabilisKrauss.B. variabiliscan be separated fromM. virgiliaeon the grounds of habitat and external morphology. The separation ofA. capensisfromM. virgiliaeis more difficult. due to similarities in habitat preference.M. virgiliaeis found at the heads of estuaries, whileA. capensisis associated with muddy substrata, close to estuary mouths. There is a considerable overlap zone in the Kowie estuary and this kind of distribution may account for some past misidentifications.

ISSN:0035-919X    

DOI:10.1080/00359198009520564

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

Using a 68 x 68 matrix of annual rainfall totals in which the rows are stations and the columns are years, principal components analysis has defined a set of uncorrelated rainfall fields over South Africa. The low-numbered principal components describe patterns over large groups of years that appear to be associated with the major forcing mechanisms for rainfall over the sub-continent. Higher numbered components are related to smaller groups of years and appear to describe phenomena of a more local nature. These results will lend themselves to further analyses in an attempt to relate spatial rainfall variations, both general and extreme such as droughts and floods, with those within the circulation of the atmosphere.

ISSN:0035-919X    

DOI:10.1080/00359198009520565

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

Eighteen series of annual rainfall totals over the non-irrigated area of the sugar region of South Africa were submitted to principal components analysis. Three components accounted for 84 per cent of the total rainfall variance. These components may be identified with the general behaviour of rainfall from year to year, a compensatory system between the northern and southern areas of the sugar region, and a minor compensatory system within the southern part of the region respectively. The first component, from a spectral analysis, exhibited three major wave patterns, namely, wave lengths of 19, 6,8 and 2.2 years. The application of band pass filters to the longest record showed that the 19-year wave has been stable over three complete cycles, the 2,2-year wave has run true over the period of record but has suffered three extreme amplitudes, while the 6,8-year wave appears not to be stable over time or amplitude. With reservations, the first two waves may have forecasting potential, but the latter one does not.

ISSN:0035-919X    

DOI:10.1080/00359198009520566

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

During the period January 1971 to July 1976, over 240 strains ofNaegleria, Acanthamoebaand other limax amoebae were isolated from a variety of habitats in South Africa and South West Africa. Seven strains ofNaegleria fowleriand a strain ofAcanthamoebawere isolated from a heavily polluted section of the Eerste River, Cape Province, South Africa. These 8 isolates have been identified as being potentially pathogenic, the first such report for Africa.

ISSN:0035-919X    

DOI:10.1080/00359198009520567

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

A histomorphological study was carried out using tongues from healthy adult southern African vervet monkeys sacrificed to obtain fresh kidney material for virological studies. The tongue was spatulate in dorsal profile and ovoid in cross-section, and the portion anterior to the four symmetrically positioned circumvallate papillae constituted 80% of its total length. There was no foramen caecum. Histological examination revealed collections of intra-cytoplasmic eosinophilic bodies in the prickle cells between the filiform papillae. These stained metachromatically with toluidine blue and positively for phospholipids using the acid haematin method with pyridine extraction as a control. Electron microscopy of the bodies showed them to be relatively homogeneous electron dense structures of varying size. No similar structures were found in specimens from human, chacma baboon, duiker and pigeon tongue fixed and processed in the same manner for light microscopy.

ISSN:0035-919X    

DOI:10.1080/00359198009520568

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

The infrared spectra (4 000 − 140 cm−1) of the L-alaninate complextrans-[Pt(L-ala)2] and its18( )-,15N, 2-d,3-d3- andN,N-d2-labelled analogues have been determined. Each spectral band has been assigned on the basis of the shifts induced by the various modes of isotopic labelling and by substitution of Pd(II) for Pt(II). The labelling study reveals that very few bands represent vibrationally-pure modes and that certain earlier assignments require revision.

ISSN:0035-919X    

DOI:10.1080/00359198009520569

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor