Articles by Keyword: History

Search results for History

We found 70 results for you
  1. Conservation Developments in South African Forestry

    Item type: Journal Article • Journal: South African Forestry Journal
    The historical development of environmental conservational activities within the South African Forestry Industry is followed, and the changing emphasis from the conservation of the remaining indigenous forests (pre-1900) to water conservation, to natural assets and unplanted areas is highlighted. The...
  2. A preliminary investigation of woody plant increase in the western Transvaal and implications for veld assessment

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    The relationships between tree density and indices of pasture and soil condition were examined in Western Transvaal grasslands where Acacia karroo had increased following disturbance. The correlation between tree density and pasture condition was not linear, indicating a threshold in...
  3. The development of veld assessment in the northern Transvaal savanna I. Red Turfveld

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    Grazing‐induced gradients in pasture species composition were characterized for the red turfveld of the Northern Transvaal savanna. A proposed classification of pasture species response to grazing was developed and the influence of state variables and driving forces other than grazing...
  4. Necessity and sufficiency in the aetiology of HIV/AIDS: The science, history and politics of the causal link

    Necessity and sufficiency in the aetiology of HIV/AIDS: The science, history and politics of the causal link

    Item type: Journal Article • Journal: African Journal of AIDS Research
    An earlier version of this paper was presented at the AIDS in Context Conference, University of the Witwatersrand, Johannesburg, 4–7 April 2001
  5. A PRELIMINARY STUDY OF ASPECTS OF THE ECOLOGY OF A RARE MINNOW <em>BARBUS TREURENSIS</em> GROENEWALD, 1958 (PISCES: CYPRINIDAE) FROM THE EASTERN TRANSVAAL, SOUTH AFRICA

    A PRELIMINARY STUDY OF ASPECTS OF THE ECOLOGY OF A RARE MINNOW <em>BARBUS TREURENSIS</em> GROENEWALD, 1958 (PISCES: CYPRINIDAE) FROM THE EASTERN TRANSVAAL, SOUTH AFRICA

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa
    The habitat preferences, food habits, reproduction, age and population size of Barbus treurensis were investigated as part of a survey of the threatened fish of the Transvaal. Barbus treurensis occurs only in an isolated section of the Blyde River tributary...
  6. DEEP SEA, ESTUARINE AND FRESHWATER FISHES: LIFE HISTORY STRATEGIES AND ECOLOGICAL BOUNDARIES

    DEEP SEA, ESTUARINE AND FRESHWATER FISHES: LIFE HISTORY STRATEGIES AND ECOLOGICAL BOUNDARIES

    Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences
    The life histories of fishes from three different ecosystems are compared and discussed with emphasis on species that move between habitats: between estuary and sea in tropical northern Australia; between bottom waters and pelagic waters of the temperate continental slope...
  7. INFLUENCE OF FRESHWATER FLOW REGIME ON FISH ASSEMBLAGES IN THE GREAT FISH RIVER AND ESTUARY

    INFLUENCE OF FRESHWATER FLOW REGIME ON FISH ASSEMBLAGES IN THE GREAT FISH RIVER AND ESTUARY

    Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences
    Two and a half years of data were collected from the lower Great Fish River, head region and estuary to determine the fish species composition within these areas. Gilchristella aestuaria, Liza dumerilii, Rhabdosargus holubi and Pomadasys commersonnii were the four...
  8. Spatial and temporal variation in a mesic savanna fire regime: responses to variation in annual rainfall

    Spatial and temporal variation in a mesic savanna fire regime: responses to variation in annual rainfall

    Item type: Journal Article • Journal: African Journal of Range & Forage Science
    This paper analyses the fire regime over 41 years (1956 to 1996) in Hluhluwe-Umfolozi Park, a mesic savanna area in South Africa. The study focuses at the landscape scale of tens of kilometres and at the medium term temporal scale...
  9. Retraction and expansion of flock mobility in Central Asia: costs and consequences

    Retraction and expansion of flock mobility in Central Asia: costs and consequences

    Item type: Journal Article • Journal: African Journal of Range & Forage Science
    Seasonal and spatial fluctuations in forage quality, accessibility and output provide strong incentives for migratory stock keeping in Central Asia. Over the past century, mobile livestock husbandry has either been suppressed or collapsed and a fragmented pattern of rangeland use...
  10. Transformation of a savanna grassland by drought and grazing

    Transformation of a savanna grassland by drought and grazing

    Item type: Journal Article • Journal: African Journal of Range & Forage Science
    The relative effects of drought and heavy grazing on the floristic composition, population size and structure, and basal cover of an African savanna grassland were differentiated by comparing changes over eight years, which included a severe drought year, across a...