Articles by Keyword: Trophic Structure

Search results for Trophic Structure

We found 157 results for you
  1. Decline of demersal resources in North-West Africa: an analysis of Mauritanian trawl-survey data over the past 25 years

    Decline of demersal resources in North-West Africa: an analysis of Mauritanian trawl-survey data over the past 25 years

    Item type: Journal Article • Journal: African Journal of Marine Science
    Mauritania is characterised by fast-growing fisheries that have developed over the past decades. Since 1982, scientific trawl surveys have been conducted regularly, allowing assessment of the impact of this increasing fishing pressure on exploited species as well as on demersal...
  2. Trophic structure and biomass distribution of macrobenthos on sheltered and semi-exposed rocky shores of Tsitsikamma Marine Protected Area

    Trophic structure and biomass distribution of macrobenthos on sheltered and semi-exposed rocky shores of Tsitsikamma Marine Protected Area

    Item type: Journal Article • Journal: African Zoology
    The trophic structure and biomass of macrobenthos on both wave-sheltered, rocky intertidal shores and semi-exposed ones at seven localities in the Tsitsikamma Marine Protected Area were compared. In the Cochlear zone and entire intertidal (Cochlear- and Balanoid zones combined) biomass...
  3. Protected nearshore shallow and deep subtidal rocky reef communities differ in their trophic diversity but not their nutritional condition

    Protected nearshore shallow and deep subtidal rocky reef communities differ in their trophic diversity but not their nutritional condition

    Item type: Journal Article • Journal: African Journal of Marine Science
    Large physical changes that alter reef macrobenthos and fish assemblages occur with increasing depth, so the biological processes that regulate communities at different depths are expected to diverge. We used analyses of stable isotopes (δ13C and δ15N) and fatty acids...
  4. Patterns of plant selection by grazing cattle in two savanna grasslands: A plant's eye view

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    The amount of grazing experienced by individual tufts of the most abundant perennial grasses of two Transvaal savannas was monitored at regular intervals for two growing seasons. In general, Setaria incrassata and Themeda triandra were heavily grazed, Bothriochloa insculpla and...
  5. The effect of clone type and method of transportation on oil yield from vegetative material of <em>Eriocephalus punctulatus</em>

    The effect of clone type and method of transportation on oil yield from vegetative material of <em>Eriocephalus punctulatus</em>

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Eriocephalus punctulatus, also known as, ‘Kapok Bos’, belongs to the Asteraceae family. It is an attractively scented woody shrub, that reaches a height of about one metre. It produces a highly priced essential oil with a dark blue colour and...
  6. Soil aggregate properties and total available water as affected by sugar cane (<em>Saccharum hybrid</em> sp.) production in Mauritius

    Soil aggregate properties and total available water as affected by sugar cane (<em>Saccharum hybrid</em> sp.) production in Mauritius

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Concerns within the sugar industry of Mauritius with respect to soil degradation caused by sugar cane cropping have led to a study on soil quality. As part of this study, the effects of sugar cane production, i.e. cropping and adoption...
  7. Perspectives on the principles and structure of the soil classification system in South Africa: discussion and practical examples

    Perspectives on the principles and structure of the soil classification system in South Africa: discussion and practical examples

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    The paper discusses revised principles, perspectives and structure for soil classification of natural soils in South Africa. An expanded ‘sphere of pedological interest’ is proposed through the formal recognition of a wider range of subsurface soil materials. The concept of...
  8. Approach structures and measures of connectedness

    Approach structures and measures of connectedness

    Item type: Journal Article • Journal: Quaestiones Mathematicae
    Measures of connectedness versus disconnectedness are introduced in anarbitrary topological construct as fixed points of a Galois connection. This places measures of connectedness found in the literature in a general categorical frame-work.
  9. A review of orange roughy <em>Hoplostethus atlanticus</em> fisheries, estimation methods, biology and stock structure

    A review of orange roughy <em>Hoplostethus atlanticus</em> fisheries, estimation methods, biology and stock structure

    Item type: Journal Article • Journal: South African Journal of Marine Science
    Orange roughy Hoplostethus atlanticus are unusual fish. They form dense aggregations that have fuelled lucrative fisheries at great depths (600–1 400 m), especially off Namibia, New Zealand and Australia. They are thought to be very long-lived (>100 years, maturity at...
  10. VIABLE HETEROTROPHIC BACTERIAL POPULATION STRUCTURE OF A TURBID MAN-MADE IMPOUNDMENT

    VIABLE HETEROTROPHIC BACTERIAL POPULATION STRUCTURE OF A TURBID MAN-MADE IMPOUNDMENT

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa
    Seventy one heterotrophic bacterial isolates were obtained from Wuras Dam, phenotypically characterized and clustered with the unweighted-pair group method. Three groups were obtained of which the first contained 59 members in several clusters. Overall this group was characterized by a...