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Floristiese verskille tussen ekotope in die Potchefstroom distrik1
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: AnnelieS. de Beer --- Departement Landbou en Watervoorsiening, Republiek van Suid‐Afrika G.K. Theron --- Departement Plantkunde, Republiek van Suid‐Afrika G.J. Bredenkamp --- Departement Plantkunde, Republiek van Suid‐AfrikaFloristic differences between eeotopes in the Potchefstroom area. Eeotopes are generally used, in the Highveld Region, as a basis for the division of camps when planning a farm. The possible floristic differences which support this ecological approach, as well as... -
Die rol van sekere omgewingsfaktore by alachloraktiwiteit
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. Reinhardt --- Departement Plantproduksie, P.C. Nel --- Departement Plantproduksie,Biotoetse met graansorghum (Sorghum bicolor L.) is in potte in glashuise en groeikabinette uitgevoer. Geselekteerde grond- eienskappe is gekorreleer met alachloraktiwiteit. Organiese materiaalinhoud (% C) was die beste gekorreleerd met die aktiwiteit van alachlor en pH die swakste. Die r-waardes... -
Relationship between cation exchange capacity, clay content and water retention of Highveld soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: AstridM. Lambooy --- ,Water in the soil is held by capillary and adsorption forces. These forces are mainly a function of clay content and mineralogy. To neglect the influence of clay mineralogy when estimating the water-holding properties of soil, implies that only a... -
Measurement of exchangeable aluminium in soils and clay minerals by isotopic exchange
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: W. A.G. Kotzé --- , Marlise Joubert --- , Johannes.F. de Villiers --- , M. van der Westhuizen --- , D. van der Bank --- ,Isotopically exchangeable Al was determined in soils and clay minerals by equilibration with 28Al. Best results were obtained with a weak extractant and an equilibration time of eight min. The calculated amount of isotopically exchangeable Al was independent of the... -
Physical properties of some highveld Vertisols
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: K. Snyman --- , M.V. Fey --- Department of Soil Science and Agrometeorology, A. Cass --- Department of Soil Science and Agrometeorology,Surface (0–20 cm) soils were sampled at 100 m intervals along a 3 km transect through Vertisols derived from dolerite and Ecca group mudstone near Standerton, Transvaal. The two geologically correlated soil bodies, which historically appear to have formed the... -
The origin of textural lamellae in Quaternary coast sands of Natal
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: L.P. van Reeuwijk --- , The Netherlands J.M. de Villiers --- Department of Soil Science and Agrameteorotogy,A new concept of the formation of textural subsoil lamellae has been developed on the basis of their morphology in aeolian coastal deposits in Natal. It has been concluded that they are initiated somewhere at depth in the profile by... -
Physical and clay mineralogical properties of some Natal and eastern Transvaal soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Cass --- , Australia M.A. Johnston --- Department of Agriculture and Water Supply,Soils, collected from the south-eastern Transvaal, Natal north coast and the more arid areas of the Natal interior, were examined using physical, chemical and mineralogical methods. Most of the soils were associated with particular management problems such as poor internal... -
Behaviour of sesquioxic clay soils subjected to alkaline and saline effluents
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.G. Thompson --- ,The effects of disposal of alkaline and saline effluents on sesquioxic red clay soils have been monitored for many years on a site in the eastern Transvaal. Recently a high chloride content effluent with a sodium adsorption ratio (SAR) of... -
Kleimineralogie, katioonuitruilkapasiteit en waterhouvermoë van grondvorms in die Hoëveldstreek
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: AstridM. Hattingh --- Hoëveldstreek, Departement van Landbou en Watervoorsiening,Kleimineralogiese data vir 12 grondvorms, wat algemeen in die Hoëveldstreek voorkom, is ondersoek. Die persentasie monsters waarin 'n bepaalde kleimineraal voorkom, is bereken. Daaruit is dit duidelik dat smektiet algemeen in gronde van die Arcadia-, Bonheim, en Rensburgvorms voorkom, maar... -
Die invloed van verdigtingspoging, klei-en waterinhoud op verdigting van geselekteerde Hoëveldgronde
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. A.G. Henning --- Departement van Landbou en Watervoorsiening, D.J. Nel --- Departement Bodemkunde, PU vir CHO, H. J. van M. Harmse --- Departement Bodemkunde, PU vir CHO,Die verwantskap tussen kegelpenetrasieweerstand en droë brutodigtheid word deur die mate van sortering beïnvloed. By swak sortering word laer penetrasieweerstande as in die geval van matige sortering met spesifieke brutodigthede geassosieer. Waterinhoud waarby maksimum verdigting plaasvind, word deur klei-inhoud en... -
Sodicity phenomena in red sesquioxic clay subsoils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.G. Thompson --- ,Monitoring for many years of the soils of an effluent disposal site in the eastern Transvaal has shown that the disposal of alkaline and saline effluents on red sesquioxic clays has not appreciably affected soil permeability but has brought about... -
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... -
Watervlakke in sekere gronde van die Noordwestelike Oranje-Vrystaat
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. A.G. Henning --- , Republiek van Suid-Afrika D.J. Nel --- Departement Bodemkunde, P.U. vir C.H.O., Republiek van Suid-AfrikaDie akkumulasie van vrywater in sekere gronde in die Noordwestelike Oranje-Vrystaat word geassosieer met verskillende tipes stadig-deurlaatbare lae (keerlae). Voorlopige ondersoeke het aangetoon dat die langtermyn-storing van water verskil tussen twee tipes keerlaag, naamlik 'n kleilaag en 'n harde plintiese... -
Kaliumvaslegging in 'n Arcadia-grond II. Vaslegging in die kleifraksie
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.J. Steenkamp --- , Republiek van Suid-Afrika A.A. Theron --- Departement Grond- en Waterboukunde, Republiek van Suid-Afrika J.A. de Bruyn --- Departement Botanie, Republiek van Suid-AfrikaOndersoek is ingestel na die invloed van relatief lae toedienings van kalium, asook drogingstemperatuur, op die vermoë van die kleifraksie van 'n Arcadia-grond, versadig met kalsium of magnesium, om kalium vas te lê. Die verskil in reaksie tussen die behandelings... -
The effect of lime, KCl and parent material on the cation exchange capacity of some acid subsoils of the western Cape
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. Wooldridge --- , Republic of South AfricaCation exchange capacity (CEC) values obtained by 22Na dilution for a number of mineralogically diverse acid subsoils reflected positive responses to lime and to treatment with KCl such that: CEC (unlimed, no KCl) < (unlimed + KCl) < (limed, no... -
Persistence of atrazine as affected by selected soil properties
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. Reinhardt --- Department of Plant Production, Republic of South Africa J.G. Ehlers --- Department of Plant Production, Republic of South Africa P.C. Nel --- Department of Plant Production, Republic of South AfricaThe relationships between selected soil properties and the bioactivity of atrazine (2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine) were investigated in field trials. Bioactivity was determined periodically for up to twelve months on a variety of soil types using oats (Avena sativa L.) as the test... -
Urease-aktiwiteite in gronde van die sentrale besproeiingsgebiede in Suid-Afrika
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: F. P.J. Thormählen --- Departement van Grondkunde, Republiek van Suid-Afrika C.C. du Preez --- Departement van Grondkunde, Republiek van Suid-AfrikaDie oogmerk met die studie was om die omvang van urease-aktiwiteite in die besproeide gronde vas te stel en watter grondparameters dit beïnvloed. Die verloop van hidrolise is in agt gronde, afkomstig van die sentrale besproeiingsgebiede, gemonitor na toediening van... -
Estimation of soil water retention from clay content and cation exchange capacity values of soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. D.P. Botha --- , Republic of South Africa B.E. Eisenberg --- , Republic of South AfricaSoil water characteristics can be estimated accurately from the clay content and cation exchange capacity (CEC) values of soils. The clay with its very large adsorption surface and CEC which reflects the negative charge of clays, is jointly responsible for... -
Verwantskap tussen organiese materiaalinhoud van sekere onversteurde bogronde, grondeienskappe en klimaatsdata in Suid-Afrika
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.E. du Toit --- , Republiek van Suid-Afrika C.C. du Preez --- Departement van Grondkunde, Republiek van Suid-AfrikaDie doel met die ondersoek was om vas te stel of die organiese materiaalinhoud van onversteurde ortiese A-horisonte, wat deur rooi apedale, geelbruin apedale en sagte plintiese B-horisonte onderlê word, vanaf beskikbare of maklik meetbare grondeienskappe en klimaatsdata bereken kan... -
Nitrogen mineralization in selected soils from the maize producing areas of South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: GailA. van der Mey --- , Republic of South Africa H.M. Combrink --- , Republic of South Africa C.C. du Preez --- Department of Soil Science, Republic of South AfricaThe aim of this study was to relate nitrogen mineralization from soil to selected soil properties more easily obtained in the laboratory. Net nitrogen mineralization was determined to varying depths (0–200, 200–400 and 400–600 mm) in 21 soil profiles from... -
Clay-substrate application to sandy open-cast mine soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: G. Reuter --- Department of Soil Science and Plant Nutrition, GermanyThe review gives some insight into the objective of amelioration to improve fertility of sandy soils. The research concept is based on the high water and cation exchange capacity of clay minerals. Technological and economic problems as well as practicable... -
Soil mineralogy research in South Africa, 1978 to 2002 - a review
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C. Bühmann --- , South Africa B.J. Escott --- Soil Science, South Africa J.C. Hughes --- Soil Science, South AfricaOver 160 publications that contain mineralogical information were produced in the last 25 years of which about half were published in national and international journals. In many articles mineralogical data were presented but not discussed. Most studies were concerned with... -
Substrates for soil-less Disa production
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: D. Pienaar --- Department of Agronomy, Republic of South Africa N.J.J. Combrink --- Department of Agronomy, Republic of South AfricaThe effects of different substrates were investigated as root media for soil-less Disa production. In a first study, tissue cultured plantlets were hardened. In a second study, hardened plantlets were grown to the early flowering stage. In both cases, a... -
Particulate organic matter, soil texture and mineralogy relations in some Eastern Cape ecotopes in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: AD Nciizah --- Department of Agronomy, South Africa IIC Wakindiki --- Department of Agronomy, South AfricaContrasting reports have been given on the relationships between soil texture, mineralogy and particulate organic matter (POM). The objective of this study was to determine the effects of soil texture and mineralogy on aggregate POM in several ecotopes in the... -
Selected soil properties as indicators of soil water regime in the Cathedral Peak VI catchment of KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: BT Kuenene --- Department of Soil, Crop and Climate Sciences, South Africa CW van Huyssteen --- Department of Soil, Crop and Climate Sciences, South Africa PAL Le Roux --- Department of Soil, Crop and Climate Sciences, South AfricaThe morphological features and physicochemical properties of 14 soil profiles, representing the major soil types, were studied in the Cathedral Peak VI catchment of KwaZulu-Natal, South Africa. The soils are characterised by a high organic carbon content in the topsoil,... -
Site and stand analysis for growth prediction of Eucalyptus grandis on the Zululand coastal plain
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: M. du Plessis --- , J Zwolinski --- ,The integration of site information with that of tree growth is of special importance in Zululand, where sustainable supply of timber is essential for local processing and export commitments. Site prediction growth models need to be based on easily attainable... -
Determining input values for a simple parametric model to estimate evaporation from vineyard soils with special reference to clay content and trellis system
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Philip A Myburgh --- Agricultural Research Council Infruitec-Nietvoorbij, South AfricaEstimating soil evaporation (Es) is an important part of modelling vineyard evapotranspiration for irrigation purposes. Furthermore, quantification of possible soil texture and trellis effects is essential. Daily Es from six topsoils packed into lysimeters was measured under grapevines on slanting... -
Comparative study of double-chamber microbial fuel cells (DC-MFCs) using Mfensi clay as ion-exchange-partition: Effect of electrodes
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: R.Y. Tamakloe --- Department of Physics, Ghana T. Opoku-Donkor --- Department of Physics, Ghana M.K.E. Donkor --- Department of Physics, Ghana H. Agamasu --- Department of Physics, GhanaAn alternative answer to the vital issues of electricity production and wastewater treatment leads to the application of microbial fuel cells. This study has developed a low-cost double-chambered microbial fuel cell (MFC) for electricity generation, which can also be used... -
In situ evaluation of internal drainage in duplex soils of the Tukulu, Sepane and Swartland forms
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Sabelo SW Mavimbela --- Department of Soil, Crop and Climate Sciences, South Africa Leon D van Rensburg --- Department of Soil, Crop and Climate Sciences, South AfricaInternal drainage is a critical hydrological process in soil water conservation. Pedological and physical properties of the South African Tukulu, Sepane and Swartland soil types were studied in respect to soil water storage and hydraulic characteristics during internal drainage. Soil... -
Wrong pedogenetic assumptions: a case study of the soils developed over talc in Southern Guinea Savanna of Nigeria using clay mineralogy
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Godwin A Ajiboye --- Department of Soil Science and Land Management, Nigeria JA Ogunwale --- Department of Agronomy, Nigeria James Talbot --- K/T Geoservices Inc., USA Samuel A Mesele --- Department of Soil Science and Land Management, NigeriaIt is often assumed that ultrabasic parent material leads to the formation of soils rich in 2:1 clays and dibasic cations. However, in a tropical environment with intense weathering, this assumption may not be true. To investigate this assumption soil... -
Selected chemical properties of agricultural soils in the Ethiopian highlands: A rapid assessment
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Eyasu Elias --- College of Natural and Computational Sciences, Centre for Environmental Science, EthiopiaLack of information on the characteristics of soils occurring in different locations has constrained the development of soil- and site-specific fertiliser recommendations in Ethiopia. A rapid assessment of the fertility status of some dominant agricultural soils was conducted. A total... -
More than eating dirt: a review of avian geophagy
Item type: Journal Article • Journal: African Zoology • Authors: Colleen T Downs --- School of Life Sciences, South Africa Ian P Bredin --- School of Life Sciences, South Africa Peter D Wragg --- School of Life Sciences, South AfricaGeophagy, the ingestion of earth varying in particle size from stones to soils rich in clay, is a relatively widespread behaviour across avian taxa. We reviewed its occurrence in birds and its hypothesised adaptive functions in birds. Of the ∼30... -
Progress research on earth construction: Cast earth with glass wastes, cement kiln bypass dust and activated clay
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Hanaa Youssef Ghorab --- Chemistry Department, Faculty of Science, Egypt Amr Said Meawad --- Chemistry Department, Faculty of Science, Egypt Mehmet Yildirim --- Customer Support Department, Suez Cement Company, Egypt Ahmed Hassan Eied Hassan --- Chemistry Department, Faculty of Science, EgyptA sandy soil was stabilized by 10% CEM I 42.5 R. Up to 50% of the cement was replaced by waste glass powder, cement kiln bypass dust or activated clay. Polynapthalene sulfonate superplasticizer was used to increase the fluidity of... -
Ethiopian immigrants to Israel: The persistence and transformation of African values and practices in art and life
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Patricia M. Greenfield --- Department of Psychology, USA Oshrat Sulika Rotem --- Department of Education, Israel Michael Weinstock --- Department of Education, IsraelWe present a qualitative interdisciplinary study of seven Ethiopian potters who immigrated to Israel as adults. Data sources include cultural products (their clay sculptures), interviews, and archival photos at the time of immigration. Together these data sources show how these... -
Effect of mound-building termites on soil physicochemical properties and sugarcane stalk heights
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Sandile S Mthimkhulu --- South African Sugarcane Research Institute, South Africa Neil Miles --- South African Sugarcane Research Institute, South Africa Louis W Titshall --- South African Sugarcane Research Institute, South Africa Phesheya Dlamini --- Department of Plant Production, Soil Science and Agricultural Engineering, South AfricaThis study investigated soil factors responsible for localised patches of enhanced sugarcane growth on the remains of termite (Macrotermes natalensis) mounds observed on predominantly coarse-textured soils (weak sands) of KwaZulu-Natal province, South Africa. Soil samples (0–20 cm depth) were collected... -
Preliminary mineralogical and geotechnical characteristics of Zogbodomey clays in the coastal sedimentary basin of Benin (West Africa)
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Sémondji Salvien Pyrrhus Agbon --- Département des Sciences de la Terre, Bénin Nelly Carine Kelome --- Département des Sciences de la Terre, Bénin Luc Adissin Glodji --- Département des Sciences de la Terre, BéninThe Benin coastal sedimentary basin is filled with deposits of clays of diverse nature. This study focused on the characteristics of clayey materials of Zogbodomey in sight of their valorization in the construction and ceramics sectors. The clay deposit is...