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Grond‐ en afloopverlies bepalings vanaf natuurlike veld, met behulp van ‘n reënvalnabootser
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: H.A. Snyman --- , W.L.J. Van Rensburg --- , D.P.J. Opperman’ --- ,‘n Oorhoofse roterende reënvalnabootser is gebruik om die sediment‐ en afloopverliese vanaf natuurlike veld in verskillende suksessiestadia en teen verskillende hellings te bepaal. -
Effect of slope and plant cover on run‐off, soil loss and water use efficiency of natural veld
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: H A Snyman --- , W L J Van Rensburg --- ,Run‐off and soil loss were monitored from a climax, subclimax and pioneer veld, each on a 5,9%, 4,1% and 2,1% slope, by means of a rainfall simulator on a Valsrivier soil form. With rainfall intensity, soil moisture content at the... -
Pedogeomorphic aspects of the Roodepoort area, Transvaal: Soil depth-slope relationships
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.C. Munnik --- Department of Geography, E. Verster --- Department of Geography, T.C. van Rooyen --- Department of Geography,Fifty hillslope profiles with associated soils in the Roodepoort area, Transvaal, were examined to determine the relationships between soil depth and hillslope characteristics. A meso-scale approach was adopted which implied the relationship between three soil depth phases and the hillslope... -
Spatial variability of two selected soil properties in a semi- arid subcatchment of the Lower Great Fish River
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.H. Moolman --- Geography Department,The variability of the soluble salt content and the textural composition of the soil were investigated in a 28-ha sub-catchment of the Ecca River, a tributary of the Great Fish River. The frequency distribution of the soluble salts in the... -
Soils derived from granite in two Mt. Garnet toposequences, North Queensland, Australia
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: E. Verster --- Department of Geography, Republic of South AfricaTwo toposequences derived from granite in the Mt. Garnet area, North Queensland, were examined to determine the detailed soil - landform relationships in order to facilitate subsequent broad-scale mapping of the soil resource. The dominant landsurface feature is gently sloping,... -
Spatial pattern and variability of soil and hillslope properties in a granitic landscape 1. Pretoriuskop area
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.C. Munnik --- Department of Geography, Republic of South Africa E. Verster --- Department of Geography, Republic of South Africa T.H. van Rooyen --- Department of Geography, Republic of South AfricaCharacteristics of nine hillslope profiles and selected properties of 69 soil profiles were determined in order to evaluate the spatial pattern and variability of soil and hillslope properties in a granitic area near Pretoriuskop, Kruger National Park. A transect design... -
Spatial pattern and variability of soil and hillslope properties in a granitic landscape 2. Pretoria—Johannesburg area
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.C. Munnik --- Department of Geography, Republic of South Africa E. Versterand --- Department of Geography, Republic of South Africa T.H. van Rooyen --- Department of Geography, Republic of South AfricaUsing a transect design, a detailed examination was made of nine hillslopes and 64 soil profiles in the granitic area between Johannesburg and Pretoria to assess the spatial pattern and variability of soil and hillslope properties. The land surface was... -
Spatial pattern and variability of soil and hillslope properties in a granitic landscape. 3. Phalaborwa area
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.C. Munnik --- Department of Geography, Republic of South Africa E. Verster --- Department of Geography, Republic of South Africa T.H. van Rooyen --- Department of Geography, Republic of South AfricaA pedogeomorphic study was made of the area immediately east of Phalaborwa underlain by granitic materials. Fifty-five soil profiles from nine transects were examined in detail to determine, among other things, the spatial variability of the soils and the hillslope... -
Soil indicators of hillslope hydrology in the Bedford catchments, South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.J. van Tol --- Department of Soil, Crop and Climate Sciences, South Africa P.A.L. Le Roux --- Department of Soil, Crop and Climate Sciences, South Africa M. Hensley --- Department of Soil, Crop and Climate Sciences, South AfricaWater plays a primary role in soil genesis and soil strongly influences hydrological processes (flowpaths, residence times and storage). Morphological soil properties serve as indicators of hillslope hydrological behaviour and can facilitate hydrological predictions. Three catchments in the Bedford district... -
Structure of a toothed cetacean community around a tropical island (Mayotte, Mozambique Channel)
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J Kiszka --- Observatoire des Mammifères Marins, Mayotte PJ Ersts --- , USA V Ridoux --- Observatoire des Mammifères Marins, MayotteWe describe the structure of a toothed cetacean community around the island of Mayotte (South-West Indian Ocean, 45°10′ E, 12°50′ S), using data collected from small boat-based surveys conducted between July 2004 and June 2006. In all, 16 odontocete species... -
Changes in demersal fish assemblages on the west coast of South Africa, 1986–2009
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: LJ Atkinson --- , South Africa RW Leslie --- Fisheries Branch, Department of Agriculture, South Africa JG Field --- , South Africa A Jarre --- , South AfricaResearch survey data collected over 24 years (1986–2009) were used to explore long-term changes in demersal fish assemblages on the west coast of South Africa. Differences in spatial (latitude and depth) and temporal (seasonal and annual) factors were examined using... -
The fishery for, and local distribution of, Aristeus antennatus (Risso 1816) (Crustacea: Dendrobranchiata) off western Algeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: S Mouffok A Kherraz D Bouras Z BoutibaThis study presents data on the local distribution and yield of red shrimp Aristeus antennatus (Risso 1816) from a new deep-water fishery on the western Algerian slope obtained from commercial trawl fisheries at Oran and Arzew ports between 1999 and... -
Effect of residue management and fertiliser application on the productivity of a Eucalyptus hybrid and Acacia mangium planted on sloping terrain in northern Vietnam
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Nguyen Van Bich --- Tasmanian Institute of Agriculture, University of Tasmania, Australia Daniel Mendham --- CSIRO Land and Water, Australia Katherine J Evans --- Tasmanian Institute of Agriculture, University of Tasmania, Australia Tran Lam Dong --- Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Vietnam Vo Dai Hai --- Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Vietnam Hoang Van Thanh --- Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Vietnam Caroline L Mohammed --- Tasmanian Institute of Agriculture, University of Tasmania, AustraliaForest plantation growers in Vietnam commonly burn residues after harvesting and often apply suboptimal amounts of nutrients during plantation establishment. We examined whether the retention of forest residue, and application of phosphorus fertiliser at higher rates, can increase rates of... -
Comparative depth estimation of iron-ore deposit using the Data-Coordinate Interpolation Technique for airborne and ground magnetic survey variation
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: James Adeyemo Adegoke --- Department of Physics, Nigeria Gideon Oluyinka Layade --- Department of Physics, NigeriaA newly developed quantitative method, Data-Coordinate Interpolation Technique (DCIT) was used by matching the secondary and primary data to correct the variation that exists between airborne and ground magnetic depth-to-basement. The aeromagnetic data within latitude (8.000N, 8.500N) and longitude (4.000E,... -
Effect of harvest residue management on soil properties of Eucalyptus hybrid and Acacia mangium plantations planted on steep slopes in northern Vietnam
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Nguyen Van Bich --- , Australia Alieta Eyles --- , Vietnam Daniel Mendham --- , Australia Tran Lam Dong --- , Vietnam Katherine J. Evans --- , Australia Vo Dai Hai --- , Vietnam Caroline Mohammed --- , AustraliaBurning harvest residues during site preparation can compromise the soil-nutrient stock in short-rotation plantations, but this practice remains common in northern Vietnam. This study compared the effect of two contrasting harvest-residue treatments (burning vs retention) on soil total carbon (TC),... -
Identification of the landscape and bioclimatic characteristics that contribute to maintaining the allopatric distribution ranges of the Northern Black Korhaan Afrotis afraoides and the Southern Black Korhaan Afrotis afra
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Steven W Evans --- , South AfricaThe Northern Black Korhaan Afrotis afraoides and the Southern Black Korhaan Afrotis afra were previously considered conspecific, but were subsequently separated based on habitat, plumage, displays and vocalisations of the males and genetic differences. The Northern Black Korhaan is endemic... -
Wood extraction performance with a farm tractor in a mountainous region of Brazil: cycle time, productivity and costs of two different work crews
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Rafael Oliveira Brown --- , Brazil Kauê Augusto Oliveira-Nascimento --- , Brazil Renato César Gonçalves Robert --- , Brazil Daniel DeArmond --- , BrazilHarvesting is a complex and expensive step within forestry operations. In mountainous terrain timber harvesting is complex due to the risks and limitations that the terrain imposes on traditional forms of wood extraction. The objective of this study was to... -
Examining swap butterfly risk premia in South Africa
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Sanveer Hariparsad --- University of Pretoria, South Africa Eben Maré --- University of Pretoria, South AfricaThis paper studies a long butterfly strategy (which is immune to parallel curve shifts but exposed to non-parallel curve shifts) on the South African interest rate swap curve. Ten swap butterfly risk factors are identified using monthly South African swap... -
Flows with constant slope on the Klein bottle
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Luís Barreira --- Universidade de Lisboa, Portugal Jaume Llibre --- Universitat Autònoma de Barcelona, Spain Claudia Valls --- Instituto Superior Técnico, Universidade de Lisboa, PortugalWe consider smooth flows with constant slope on the 2-dimensional (flat) torus and on the (flat) Klein bottle. It is well known that for a flow with constant slope on the torus either all orbits are periodic or all orbits...