Search
Search results for
We found
19 results for you
-
Considerations on the sustainability and environmental impact of intensive pastures
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: N. Miles --- Department of Agricultural Development, Republic of South Africa A.D. Manson --- Department of Agricultural Development, Republic of South AfricaIntensive pastures form an important component of livestock production systems in South Africa. The sustainability and environmental impact of intensive pastures via their effects on soil properties and nutrient fluxes vary considerably depending on the systems adopted. Soil organic C... -
Vergelyking van ammoniumsulfaat, kalksteenammo- niumnitraat en ureum onder besproeiingstoestande op twee gronde van die Vaalhartsbesproeiingskema
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.J. Snyman --- , R. du T. Burger --- Departement Grondkunde, M.C. Laker --- Departement Grondkunde,Op 'n sandgrond met 9% klei in die B21-horison het ammoniumsulfaat hoër koringopbrengste gelewer as kalksteenammoniumnitraat en ureum. 'n Sandleemgrond met 20% klei in die B21-horison, het geen verskille tussen stikstofbronne getoon nie. Logingstudies in grondkolomme het aangetoon dat feitlik... -
On the concept of leaching requirement for salinity control
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.M. du Plessis --- ,The concept of irrigating in excess of plant water requirement to restrict soil profile salinity to acceptable limits is well established. The tolerable upper salinity limit is used to calculate the leaching requirement. This upper limit is determined mainly by... -
Kaliumvaslegging in 'n Arcadia-grond: I. Vaslegging onder natuurlike toestande
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.J. Steenkamp --- , Republiek van Suid-Afrika A.A. Theron --- Departement Grand- en Waterboukunde, Republiek van Suid-Afrika J.A. de Bruyn --- Departement Plantkunde, Republiek van Suid-AfrikaTen einde die mate van kaliumvaslegging op 'n grand van die Arcadia-serie onder natuurlike toestande na te gaan, is grondmonsters van 'n reeks proefpersele geneem. Die persele het verskillende hoeveelhede kaliumbemesting oor 'n periode van 12 jaar ontvang. Die monsters... -
A vacuum filtration and leaching method for the colorimetric determination of ammonium and nitrate nitrogen in soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. D.P. Botha --- , Republic of South Africa J.C. Johnson --- , Republic of South AfricaThe extracting solution and soil were separated by using vacuum filtration, followed by continuous leaching. The procedure was evaluated by spiking five different topsoil samples (having a wide range of physical and chemical properties) with ammonium nitrate and determining the... -
A slope sequence of Podzols in the southern Cape, South Africa 1. Physical and micromorphological properties
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: L.C. Hawker --- Department of Geography, South Africa T.H. van Rooyen --- Department of Geography, South Africa R.W. Fitzpatrick --- Department of Geography, South AfricaIn South Africa the characteristics of Podzols, with or without placic horizons, and the complex processes involved in their formation, are generally still poorly understood. To investigate both these aspects thoroughly, these soils were studied in the landscape context, described... -
Quantitative bioassays for monitoring the dissipation of atrazine in soil
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. Reinhardt --- Department of Plant Production, Republic of South Africa P.C. Nel --- Department of Plant Production, Republic of South AfricaA simple bioassay technique was used to study the residual activity of atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] applied at 0.25 kg ai ha−1 at different depths in a sandy clay loam (22% clay; 0.31% organic C) soil. Oats (Avena sativa L. cv. SWK001)... -
The use of a sewage sludge as a fertilizer for wheat in a glasshouse pot experiment
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.C. Hughes --- Department of Agronomy, Republic of South Africa A.D. Noble --- Department of Agronomy, Republic of South Africa S. Scott-Brown --- Department of Agronomy, Republic of South AfricaAcid soil infertility is a major limiting factor in crop production on soils along the eastern seaboard of South Africa. Invariably this problem is addressed by effectively liming the topsoil with little influence on subsoil acidity. A study was conducted... -
Simple regression models for the qualitative prediction of atrazine and terbuthylazine leaching
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. Reinhardt --- Department of Plant Production and Soil Science, South Africa K.J. Hugo --- Department of Plant Production and Soil Science, South AfricaLeaching of atrazine [6-chloro-N-ethyf-N′-(methylethyl)-1,3,5-triazine-2,4-dlamine] and terbuthylazine [6-chloro- N-(1,1-dirnelhylethyt)-N′-ethyl-1,3,5-triazlne-2,4-diamine] was studied in 23 soils by means of the soil thick-layer leaching method. The equivalent of 4 kg ai ha−1 of both herbicides was leached with water equivalent to 129 mm rain... -
Bromide movement and uptake under bare and cropped soil conditions at Dire Dawa, Ethiopia
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: K. Tilahun --- , Ethiopia J.F. Botha --- Institute for Groundwater Studies, Republic of South Africa A. T.P. Bennie --- Department of Soil, Crop, and Climate Sciences, Republic of South AfricaThe worst-case scenario of NO3-N leaching is often determined using conservative tracers since it undergoes complex and interdependent transformations in the soil. However, few tracer studies have hitherto been done under cropped soil conditions. In this study, a field experiment... -
7. Problems in Using Vegetation or Soil Classification in Determining Site Quality
Item type: Journal Article • Journal: South African Forestry Journal • Authors: A. P.G. Schönau --- , South AfricaThis paper discusses the concepts of site and site quality and reviews briefly the determination of the latter. Site quality is viewed primarily as productive capacity of forest land, although other aspects are considered also. It is concluded that nowadays... -
Soil classification groups to quantify primary salinity, sodicity and alkalinity in South African soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Johannes P Nell --- Agricultural Research Council–Institute for Soil, Climate and Water, South Africa Cornelius W van Huyssteen --- Department of Soil, Crop and Climate Science, South AfricaThis study aimed to quantify the primary salinity, sodicity and alkalinity of South African soils based on soil classification groups and rainfall classes, by using available analysed data. The 73 soil forms used by the Soil Classification Working Group were... -
Influence of local environmental conditions and bleaching histories on the diversity and distribution of Symbiodinium in reef-building corals in Tanzania
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: LJ Chauka --- Institute of Marine Sciences, Tanzania G Steinert --- Institute for Chemistry and Biology of the Marine Environment (ICBM), Germany MSP Mtolera --- Institute of Marine Sciences, TanzaniaPollution, turbidity and coral bleaching history, as well as coral diversity, vary along the Tanzanian coastline. Prior to this study, it was not known whether exposure to such environmental variation might have influenced the diversity and distribution of Symbiodinium along... -
Sublittoral seaweed communities on natural and artificial substrata in a high-latitude coral community in South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Gersun --- Department of Biological Sciences and Marine Research Institute, South Africa RJ Anderson --- Department of Biological Sciences and Marine Research Institute, South Africa JR Hart --- Oceanographic Research Institute, South Africa GW Maneveldt --- Department of Biodiversity and Conservation Biology, South Africa JJ Bolton --- Department of Biological Sciences and Marine Research Institute, South AfricaCoral mortality may result in macroalgal proliferation or a phase shift into an alga-dominated state. Subtidal, high-latitude western Indian Ocean coral communities at Sodwana Bay on the KwaZulu-Natal coast, South Africa, have experienced some mortality because of warm-water anomalies, storms... -
Temporal effects of biocontrol processes on nutrient dynamics in a shallow lake: Case study of Lake Xini, Okavango Delta in Botswana
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CN Kurugundla --- , Botswana JC Buru --- , AustraliaLittle is known about the effects of weeds on nutrient concentration changes in aquatic environments. We examined alterations to nutrient dynamics from the biocontrol process of Salvinia molesta by the weevil Cyrtobagous salviniae in the Lake Xini of Okavango, Botswana... -
Aluminium and manganese leaching and retention in two contrasting soils treated with aluminium-based sludge water in a column experiment
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S Dube --- , South Africa P Muchaonyerwa --- , South Africa F Mapanda --- , Zimbabwe JC Hughes --- , South AfricaLiquid waste (sludge water (SW)) from treatment of drinking water contains impurities which pose disposal challenges. Irrigation with SW could be a solution for the Morton Jaffray Water Works. This study was conducted to determine the effects of SW dilution... -
Long-term experimental data and crop modelling to inform the ecological intensification of irrigated wheat production in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S Magwaza --- University of Pretoria, South Africa M van der Laan --- University of Pretoria, South Africa D Marais --- University of Pretoria, South AfricaWheat (Triticum aestivum L.) production is threatened by climate change and the decline in agricultural land available due to urbanisation, farmers switching to other crops, and environmental degradation. The aim of this study was to investigate the ecological intensification (EI)... -
Aspirations and meanings of lighter skin tone in the African context: A rapid review
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Sikelelwa Ntsokota --- North-West University, South Africa Lelanie Malan --- North-West University, South Africa Esmé van Rensburg --- North-West University, South Africa Werner de Klerk --- North-West University, South AfricaAcross cultures, skin tone is associated with social impressions and outcomes, but the meanings and implications of these associations has not garnered clear research evidence. This rapid review aimed to aggregate the evidence regarding the ascribed meanings and implications of... -
Impact of long-term pig slurry application on phosphorus fractions in profiles of contrasting soils in KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Sbonakaliso Msizeni Zwane --- University of KwaZulu-Natal, South Africa Pardon Muchaonyerwa --- University of KwaZulu-Natal, South AfricaLong-term applications of pig slurry (PS) can lead to phosphorus (P) accumulation in soil, but its distribution across soil profiles remains poorly studied, particularly after 50 years of PS application on pasture soils, compared to undisturbed and cropped Luvisols, and...