Articles by Author: C L De Moor

Search results for C L De Moor

We found 18 results for you
  1. TOXIC CONCENTRATION OF FREE AMMONIA TO <em>BRACHIONUS CALYCIFLORUS</em> PALLAS, A ROTIFER PEST SPECIES FOUND IN HIGH RATE ALGAL PONDS (HRAP's)

    TOXIC CONCENTRATION OF FREE AMMONIA TO <em>BRACHIONUS CALYCIFLORUS</em> PALLAS, A ROTIFER PEST SPECIES FOUND IN HIGH RATE ALGAL PONDS (HRAP's)

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa
    Laboratory tests on Brachionus calyciflorus Pallas indicate that at low concentrations of free ammonia (< 7 mg l −1) pH levels up to 9,85 could be tolerated for 96 h without apparent ill effect. Free ammonia concentrations > 14,4 mg...
  2. DIGESTION OF <em>MICROCYSTIS AERUGINOSA</em> BY <em>OREOCHROMIS MOSSAMBICUS</em>

    DIGESTION OF <em>MICROCYSTIS AERUGINOSA</em> BY <em>OREOCHROMIS MOSSAMBICUS</em>

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa
    The mean assimilation efficiency of aquarium acclimatized Oreochromis mossambiaue fed on a diet of Microcystis aeruginosa collected from Hartbeespoort Dam was determined as 50,8% for total organic matter, 63,7% for protein and 75,5% for phosphorus. Transmission electron microscopic examination of...
  3. The macroinvertebrates of the Cunene River from the Ruacana Falls to the river mouth and assessment of the conservation status of the river

    The macroinvertebrates of the Cunene River from the Ruacana Falls to the river mouth and assessment of the conservation status of the river

    Item type: Journal Article • Journal: African Journal of Aquatic Science
    The proposed construction of a second hydroelectric power-generating dam on the Cunene (Kunene) River on the Namibia-Angola border, more than 100km downstream of the Ruacana hydroelectric power plant, will have a major influence on the aquatic biota of this river...
  4. Estimation of preferred water flow parameters for four species of <em>Simulium</em> (Diptera: Simuliidae) in small clear streams in South Africa

    Estimation of preferred water flow parameters for four species of <em>Simulium</em> (Diptera: Simuliidae) in small clear streams in South Africa

    Item type: Journal Article • Journal: African Journal of Aquatic Science
    Blackfly larvae typically occur in fast-flowing riffle sections of rivers, with different blackfly species showing preferences for different hydraulic conditions. Very little quantitative data exist on hydraulic conditions linked to the blackfly species occurring in South African streams. Stones-in-current biotopes...
  5. Potential impacts of alien freshwater crayfish in South Africa

    Potential impacts of alien freshwater crayfish in South Africa

    Item type: Journal Article • Journal: African Journal of Aquatic Science
    The habitat preferences and life history characteristics of four alien species of freshwater crayfish (Cherax tenuimanus, C. destructor, C. quadricarinatus and Procambarus clarkii) are reviewed. The potential impact of these species on South African freshwater ecosystems is assessed and the...
  6. The effect of largemouth bass <em>Micropterus salmoides</em> on aquatic macro-invertebrate communities in the Wit River, Eastern Cape, South Africa

    The effect of largemouth bass <em>Micropterus salmoides</em> on aquatic macro-invertebrate communities in the Wit River, Eastern Cape, South Africa

    Item type: Journal Article • Journal: African Journal of Aquatic Science
    Fish predation is one of the driving forces of freshwater invertebrate community structures, with alien predators having a pronounced effect. A quantitative assessment of aquatic invertebrates in the Wit River, Sundays River catchment, Eastern Cape, South Africa, was undertaken to...
  7. Can anchovy age structure be estimated from length distribution data collected during surveys?

    Can anchovy age structure be estimated from length distribution data collected during surveys?

    Item type: Journal Article • Journal: African Journal of Marine Science
    Historically, a time-series of proportions-at-age 1 from annual November hydro-acoustic surveys has been used to inform the assessment of, and in particular the choice of appropriate values for juvenile and adult natural mortality for, the South African anchovy Engraulis encrasicolus...
  8. Impact of winter flow regulation on pest-level populations of blackfly (Diptera: Simuliidae) and non-target faunal communities in a South African river

    Impact of winter flow regulation on pest-level populations of blackfly (Diptera: Simuliidae) and non-target faunal communities in a South African river

    Item type: Journal Article • Journal: African Journal of Aquatic Science
    The mid-reaches of the Great Fish River in the Eastern Cape Province of South Africa experience regular outbreaks of the pest blackfly Simulium chutteri as a direct consequence of increased flows caused by an inter-basin transfer scheme. There are opportunities...