Articles by Author: Johan Fourie

Search results for Johan Fourie

We found 139 results for you
  1. Effects of soil surface management practices on soil and tree parameters in a ‘Cripps Pink’/M7 apple orchard 1. Mineral nutrition

    Effects of soil surface management practices on soil and tree parameters in a ‘Cripps Pink’/M7 apple orchard 1. Mineral nutrition

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Effects on soil, leaf and fruit element concentrations of organic (compost, straw mulch and hand weeding) and integrated (inorganic fertilisers and herbicide usage; IP) soil surface management practices in the tree rows, in combination with weed covers, cover crops and...
  2. Effects of soil surface management practices on soil and tree parameters in a ‘Cripps Pink’/M7 apple orchard 2. Tree performance and root distribution

    Effects of soil surface management practices on soil and tree parameters in a ‘Cripps Pink’/M7 apple orchard 2. Tree performance and root distribution

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Effects of integrated production (IP) and organic-acceptable soil surface management practices were investigated in a ‘Cripps Pink’/M7 apple orchard in the Elgin area, South Africa. Work row treatments included cover crops, weeds and straw mulch. In the IP tree rows,...
  3. Teaching Community Psychology as Community Engagement

    Teaching Community Psychology as Community Engagement

    Item type: Journal Article • Journal: Journal of Psychology in Africa
    This report describes a model for teaching community psychology as a form of community engagement and the related practices to encourage active engagement between students and their communities. As active community learners, students need to explore self, family and community...
  4. The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 1: Tensor Norms

    The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 1: Tensor Norms

    Item type: Journal Article • Journal: Quaestiones Mathematicae
    This paper presents the first of a multi-part series of papers on the metric theory of tensor products according to Grothendieck's "Résumé de la theorie metrique des produits tensoriels topologiques "It contains the basics on tensor norms: a discussion of...
  5. The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 2: Bilinear Forms and Linear Operators Of Type<sub> α</sub>

    The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 2: Bilinear Forms and Linear Operators Of Type<sub> α</sub>

    Item type: Journal Article • Journal: Quaestiones Mathematicae
    In this continuation of our exposition and expansion of Grothendieck's 'Résumé,' we broach the subject of bilinear forms and operators of type α, where α is a tensor norm, and follow that up with the closely related subject of α-nuclearity.
  6. The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 3: Vector Sequence Spaces

    The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 3: Vector Sequence Spaces

    Item type: Journal Article • Journal: Quaestiones Mathematicae
    In this part of our exposition and expansion of Grothendieck's work on the metric theory of tensor products we look at the behaviour of the injective and surjective tensor norms in the case where one of the component spaces is...
  7. The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 4: The Role of C (<em>K</em>)-spaces and L<sup>1</sup>-spaces

    The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 4: The Role of C (<em>K</em>)-spaces and L<sup>1</sup>-spaces

    Item type: Journal Article • Journal: Quaestiones Mathematicae
    In this continuation of our multiseries on Grothendieck's 'Résumé', we look at the special place of C(K)-spaces and L 1-spaces in the general metric theory of tensor products.
  8. The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 5: Injective and Projective Tensor Norms

    The Metric Theory of Tensor Products (Grothendieck's Résumé Revisited) Part 5: Injective and Projective Tensor Norms

    Item type: Journal Article • Journal: Quaestiones Mathematicae
    In this continuation of our multiseries on Grothendieck's 'Resume', we look at the projective and injective properties of general tensor norms. We also introduce the concepts of left and right injectivity as well as left and right projectivity.
  9. Evaluation of natural pastures : Quantitative criteria for assessing condition in the <em>themeda</em> veld of the orange free state

    Evaluation of natural pastures : Quantitative criteria for assessing condition in the <em>themeda</em> veld of the orange free state

    There is a need for objective standards of veld condition assessment in South Africa. The alternative practical criteria of condition are examined and their field application is evaluated. Examples of quality, productivity and acceptability ratings are quoted from local research...
  10. A comparative study of three veld types of the Northern Cape: Species evaluation and yield<sup>1</sup>

    A comparative study of three veld types of the Northern Cape: Species evaluation and yield<sup>1</sup>

    A comparative study was undertaken of the grass component of the three main veld types of the Vryburg district; namely Sand veld, Dolomite veld and Lime veld. Results indicate that different species within the same veld type and the same...