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1. 

   Influence of Soil Organic Matter Content on the Responsiveness of Eucalyptus grandis to Nitrogen Fertiliser

   Item type: Journal Article • Journal: South African Forestry Journal • Authors: A.D. Noble --- Institute for Commercial Forestry Research, South Africa M.A. Herbert --- Institute for Commercial Forestry Research, South Africa

   It is widely recognised that the inherent nitrogen (N) mineralisation capacity of a soil is directly related to the organic matter content. Consequently, in estimating the N requirements of Eucalyptus grandis at planting this mineralisation potential must be taken into...

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2. Fertilizer requirements and production of Anthephora pubescens nees on a soil of the mangano series in the northern cape

   Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: J.H. Fourie --- Department of Agriculture and Water Supply, L.G. Du Pisani --- Department of Agriculture and Water Supply, C.H. Donaldson --- Department of Agriculture and Water Supply,

   The reaction of Anthephora pubescens to N, P and K fertilization was evaluated from 1976 to 1983. Dry matter production at N levels of 0; 75 and 150 kg/ha were 1,9; 2,2 and 2,3 ton/ha respectively. This relative poor reaction...

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3. Die invloed van bemesting op die spesiesamestelling en basale bedekking van beweide veld in die Potchefstroom‐omgewing

   Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: FranciP. Janse van Rensburg --- Departement Landbou en Watervoorsiening, Republiek van Suid‐Afrika R.H. Drewes --- Departement Landbou en Watervoorsiening, Republiek van Suid‐Afrika J.W. Cilliers --- Departement Landbou en Watervoorsiening, Republiek van Suid‐Afrika A.C. Beckerling --- Departement Landbou en Watervoorsiening, Republiek van Suid‐Afrika

   The impact of fertilization on veld in the Potchefstroom area was investigated. Nitrogen and phosphorus were applied annually from 1972/73 until 1981/82. The control plots and the fertilized plots were grazed with year‐old steers. Species composition and basal cover were...

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4. Responses of Italian ryegrass to phosphorus on highly‐weathered soils

   Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: N. Miles --- Department of Agricultural Development, Republic of South Africa R.J. Eckard --- Department of Agricultural Development, Republic of South Africa J.M. deVilliers --- Department of Agronomy, Republic of South Africa

   Italian ryegrass (Loliwn multiflorum cv. Midmar) responses to fertilizer P were studied in field experiments under irrigation on highly‐weathered ferrallitic soils at two localities in Natal. Each experiment was conducted over two seasons (1985 and 1986), the pasture being re‐established...

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5. Defoliation effects on resource allocation in Arizona cottontop (Digitaria californica) and Lehmann lovegrass (Eragrostis lehmanniana)

   Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: JerryR. Cox --- , Republic of South Africa M. Giner‐Mendoza --- , Mexico A.K. Dobrenz --- Plant Sciences Department, United States of America MarieF. Smith --- , Republic of South Africa

   Arizona cottontop (Digitaria californica), a bunchgrass native to the Chihuahuan and Sonoran Deserts in North America, and Lehmann lovegrass (Eragrostis lehmanniana), a bunchgrass introduced to the southwestern USA from southern Africa, were defoliated and examined for above‐ and below‐ground productivity,...

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6. 

   Land application of sewage sludge: Phosphorus considerations

   Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.J. McLaughlin --- ,

   Phosphorus considerations are gaining increasing attention where sewage sludges are applied to land because of the continuing trend of rising P levels in sludges and the growing concern for environmental pollution and nutrient recycling issues. P in sludges has reached...

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7. 

   Response of five soybean (Glycine max (L.) Merr.) cultivars to lime and phosphorus on an acid Normandien subsoil

   Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.D. Noble --- Department of Crop Science, J.D. Lea --- Department of Crop Science, M.V. Fey --- Department of Soil Science and Agrometeorology,

   Five soybean cultivars (Hill, Geduld, Forrest, Welkom and Oribi), previously selected for Al tolerance or sensitivity by a rapid seedling evaluation method, were grown in acid soil treated with varying rates of lime and P. After 35 days the plants...

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8. 

   Genotypic tolerance of selected dry bean (Phaseolus vulgaris L.) cultivar s to soluble Al and to acid, low P soil conditions

   Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.D. Noble --- Department of Crop Science, J.D. Lea --- Department of Crop Science, M.V. Fey --- Department of Soil Science and Agrometeorology,

   Twelve dry bean cultivare were grown for seven days on filter paper soaked with nutrient solution containing a range of up to 10 mmol Al dm−3. Differential response to Al toxicity, measured as taproot elongation, occurred at Al concentrations of...

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9. 

   Die invloed van fosfor, nitraat en ammonium op die opname en vervoer van stikstof en fosfor en op die groei van koring

   Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.S. Claassens --- Departement Grondkunde en Plantvoeding, W.J. Fölscher --- Departement Grondkunde en Plantvoeding,

   In 'n waterkultuureksperiment met koring is die invloed van verskillende P-toedienings (0,02 tot 5,0 me H2PO4 dm−3) en van verskillende NH4:NO3-verhoudings (0:15 tot 12:3) met 'n Hoagland-voedingsoplossing (no. 2) as kontrole bestudeer. Normale groei is reeds by 'n laer P-voorsiening...

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10. 

    Invloed van bemesting op die oliekonsentrasie oliekwaliteit van sonneblomsaad

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.L. Loubser --- Olie- en Proteïensadesentrum, Departement Landbou en Watervoorsiening, C.L. Grimbeek --- Olie- en Proteïensadesentrum, Departement Landbou en Watervoorsiening,

    Influence of fertilization on the oil concentration and oil quality of sunflower seed. Fertilizer trials (N,P,K and lime) were conducted over two seasons at three localities. Results indicate that 150 kg N ha−1 fertilizer decreased the oil concentration of the...

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11. 

    Reproduktiewe opbrengskomponente van mielies (Zea mays L.) soos beïnvloed deur verskillende grondvrugbaarheids- en be- sproeiingspeile

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: R.E. Steynberg --- Departement Plantproduksie, Republiek van Suid-Afrika P.C. Nel --- Departement Plantproduksie, Republiek van Suid-Afrika P.S. Hammes --- Departement Plantproduksie, Republiek van Suid-Afrika

    Die reproduktiewe opbrengskomponente van mielies (Zea mays L.) is gedurende die 1982/83-seisoen gemonitor by sekere behandelings van 'n langtermyn bemestings- en besproeiingsproef met twee peile elk van besproeiing (W), stikstof (N), fosfor (P), kallum (K) en kompos (M). Addisionele besproeiing...

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12. 

    Die invloed van grond-pH op die ekstraheerbare fosfor, kalium, kalsium en magnesium met bikarbonaat as ekstraheermiddel

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.J. Vorster --- , Republiek van Suid-Afrika P.J. Snyman --- , Republiek van Suid-Afrika

    Met behulp van grond-pH is Olsen se natriumbikarbonaat- ekstraheerbare fosfor en ammoniumasetaat-ekstraheerbare kalium, kalsium en magnesium met die gewysigde ISFEI- (NH4HCO3 - Na-EDTA - NH4F) ekstraksiemetode vergelyk. Op grond van pH (CaCl2) is die grondmonsters wat in die ondersoek gebruik...

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13. 

    The optimization of nitrogen and phosphorus application to cultivated Digitaria eriantha ssp. eriantha pasture

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.J. van Rooyen --- Directorate of Biometric and Datametric Services, Department of Agriculture and Water Affairs, Republic of South Africa C.S. Dannhauser --- Highveld Region, Department of Agriculture and Water Affairs, Republic of South Africa

    A production function is derived and calibrated for Digitaria eriantha hay production in the Highveld region of the RSA. A procedure is described that optimizes this function for nitrogen and phosphorus application rates within economic and risk constraints at different...

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14. 

    Invloed van bemesting op sonneblomme. I. Saadopbrengs

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.L. Loubser --- , Republiek van Suid-Afrika C.L. Grimbeek --- , Republiek van Suid-Afrika Beulah Bronkhorst --- , Republiek van Suid-Afrika

    Bemestingsproewe is by drie lokaliteite oor vier seisoene uitgevoer deur 'n ongerepliseerde 43-gestrengelde faktoriaaluitleg te gebruik. Peile het gewissel van 0 tot 150 kg N ha−1, 0 tot 45 kg P ha−1, 0 tot 60 kg K ha−1 by twee...

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15. 

    The influence of different P, NH⁺ ₄ and NO⁻ ₃ supply levels on the yield and P and Ca relationships in wheat

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.S. Claassens --- Department Soil Science and Plant Nutrition, Republic of South Africa W.J. Fölscher --- Department Soil Science and Plant Nutrition, Republic of South Africa

    In a water culture experiment with wheat, the influence on growth and nutrient uptake of varying the P supply from 0,02 to 5 mmol H2PO4 − dm−3 and the NH4 +:NO3 − ratio from 0:15 to 12:3, with a Hoagland...

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16. 

    A comparison beween short-term chemical and biological methods to measure phosphorus availability in sludge-amended sesquioxic soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.J. McLaughlin --- , Republic of South Africa

    Due to the transformations which sludge undergoes after addition to soil, single measurements of P availability are of little value in soils which have recently received additions of sewage sludge. This study assessed six procedures on two soils—a clay of...

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17. 

    Drought sensitivity of maize (Zea mays L.) in relation to soil fertility and water stress during different growth stages

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: R.E. Steynberg --- Department of Plant Production, Republic of South Africa P.C. Nel --- Department of Plant Production, Republic of South Africa P.S. Hammes --- Department of Plant Production, Republic of South Africa

    Maize was grown under controlled conditions in a pot experiment to determine how drought sensitivity would be affected by differential soil fertilities. Soil was obtained from a fertilization field trial where soil fertility differences developed over a period of 45...

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18. 

    Effect of soil nutritional status and irrigation on plant available water of wheat (Triticum aestivum L.)

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.G. Annandale --- Department of Plant Production, Republic of South Africa A.A. Nel --- Department of Plant Production, Republic of South Africa P.C. Nel --- Department of Plant Production, Republic of South Africa

    Plant available water (PAW) is the amount of water in the soil profile available for crop use. When irrigation management is based on a percentage depletion of PAW accurate estimates of PAW are essential and it is important that factors...

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19. 

    Invloed van bemesting op sonneblomme. II. N-, P- en K-verwydering deur die gewas

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.L. Loubser --- , Republiek van Suid-Afrika C.L. Grimbeek --- , Republiek van Suid-Afrika Beulah Bronkhorst --- , Republiek van Suid-Afrika

    N-, P- en K-ontledings is gedoen op saad- en plantmonsters wat verkry is uit twee NPK bemestingsproewe en een N × P × kalkproef. Die resultate is gebruik om die N-, P- en K-verwydering deur verskillende plantdele te bereken. Daar...

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20. 

    Quantities of phosphorus fertilizer required to raise the soil test value

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M.A. Johnston --- Department of Agronomy, Republic of South Africa N. Miles --- , Republic of South Africa G.R. Thibaud --- Summer Grain Sub-Centre, Republic of South Africa

    To calculate nutrient requirement it is necessary to know how much of that nutrient must be applied to overcome any buffering effects and raise the test value to a desired level. A glasshouse study was conducted on a wide range...

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21. 

    Concentration, accumulation and uptake rate of macro-nutrients by winter wheat under irrigation

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.C. du Preez --- Department of Soil Science, Republic of South Africa A. T.P. Bennie --- Department of Soil Science, Republic of South Africa

    The objective of this study was to obtain information on the nutrient uptake patterns of winter wheat (Triticum aestivum L.) grown under normal irrigation farming conditions. Except for irrigation scheduling, 13 farmers were allowed to follow their normal farming practices...

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22. 

    Lime-phosphorus interactions in the growth of temperate pasture species on highly-weathered soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N. Miles --- Department of Agricultural Development, Republic of South Africa R.J. Eckard --- Department of Agricultural Development, Republic of South Africa

    Lime and phosphorus (P) requirements for the growth of temperate pasture species on acid, well-drained soils in the Natal Midlands were evaluated in factorial field trials. Species studied were white clover (Trifolium repens), tall fescue (Festuca arundinacea) and Italian ryegrass...

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23. 

    Assessment of phosphorus availability in soils fertilized with Langebaan rock phosphate or superphosphate

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: G.R. Thibaud --- , Republic of South Africa M. P.W. Farina --- , Republic of South Africa J.C. Hughes --- Department of Agronomy, Republic of South Africa M.A. Johnston --- Department of Agronomy, Republic of South Africa

    Problems currently exist in the interpretation of soil test values for soils fertilized with rock phosphate. This study was undertaken to compare the ability of four extradants (Ambic, Bray 1, Mehlich 3 and modified Truog) to assess plant available phosphorus...

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24. 

    Phosphorus sorption in Natal soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S.H. Bainbridge --- Department of Agriculture, Republic of South Africa N. Miles --- Department of Agriculture, Republic of South Africa R. Praan --- Department of Agriculture, Republic of South Africa M.A. Johnston --- Department of Agronomy, Republic of South Africa

    Phosphorus (P) sorption poses a severe constraint on the ability of many soils to supply adequate amounts of P to plants. In an effort to quantify the P sorption capacities of soils in Natal, P sorption isotherms of 50 topsoils...

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25. 

    Fosfor in geselekteerde onversteurde en bewerkte Suid-Afrikaanse gronde 1. Totale, anorganiese en organiese fosfor

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.J. van Zyl --- Departement Grondkunde, Republiek van Suid-Afrika C.C. du Preez --- Departement Grondkunde, Republiek van Suid-Afrika

    Min is bekend oor die effek van boerderypraktyke soos bewerking, bemesting en bekalking op die fosforfraksies in gronde van die somerreënvalgebied (25°-30°S; 24°–30°O) in Suid-Afrika. Die doelstellings van die studie was om die effek van gewasverbouing op die totale (Pt),...

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26. 

    The relationship between the phosphorus requirement and some phosphorus characteristics of selected soils of the South African tobacco industry

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.C. Henry --- , MarieF. Smith --- ,

    Estimates of the phosphorus requirement (P0.11) of 20 selected soils of the South African tobacco industry were interpolated from phosphorus sorption isotherms. The relationships between P0.11 and various soil phosphorus characteristics, including Bray 2 P content and various indices of...

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27. 

    A single point sorption test for the routine determination of the phosphorus requirement of low to moderate P-fixing soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.C. Henry --- , MarieF. Smith --- ,

    The phosphorus requirement (P0.11) of low to moderate P-fixing soils from the South African tobacco industry and KwaZulu-Natal was interpolated from multiple point P sorption isotherms. The relationship between P0.11 and a single point sorption measurement, consisting of the P...

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28. 

    Relationships between Ambic 1 and Bray 1 extractable phosphorus in some South African arable soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C. J.J. Schmidt --- , South Africa F.G. Adriaanse --- , South Africa C.C. du Preez --- Department of Soil, South Africa

    South African analytical laboratories use different extractants for P in soils of which the most important are Bray 1, Ambic 1, Bray 2, Truog and Olsen. The fertilizer industry prefers to use Bray 1 extractions for fertilization recommendations and the...

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29. 

    A study of the kinetics of the adsorption of phosphorus by selected South African soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.C. Henry --- , MarieF. Smith --- ,

    Plots of the decline of the concentration of phosphorus in soil suspensions over time were constructed for 23 selected soils from South Africa and, using non-linear regression analysis, various models were fitted to the time curves, including mechanistic first and...

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30. 

    Changes in inorganic phosphorus following incubation of some Zambian soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: K. Kumoyo --- Department of Soil Science, Zambia O.A. Yerokun --- Department of Soil Science, Zambia M.I. Damaseke --- , Zambia

    Phosphorus (P) deficiency is a major problem of many Zambian soils and annual applications of the recommended 60 kg P2O5 ha−1 (26 kg−1 ha−1) do not seem to reverse this trend. In order to better understand the dynamics of P...

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31. 

    The relationship between the phosphorus requirement and Ambic 1 phosphorus content of selected South African soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.C. Henry --- , MarieF. Smith --- ,

    The phosphorus requirement (P0.11) of low to moderate P-fixing soils from the South African tobacco industry and KwaZulu-Natal was estimated from P sorption isotherms. The relationships between P0.11, Ambic 1 P, clay content and various indices of P sorption were...

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32. 

    Retention of applied phosphorus by the benchmark soils of Lesotho and quantification of their phosphorus retention indices

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S.F. Molete --- Department of Soil, Crop and Climate Sciences, South Africa C.C. du Preez --- Department of Soil, Crop and Climate Sciences, South Africa M.V. Marake --- Faculty of Agriculture, Lesotho

    This study was conducted with the objective of determining and quantifying the capacity of Lesotho's benchmark soils to retain applied P. The soils were incubated with a range of P levels for a period of 42 days, whereafter P retention...

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33. 

    Plant nutrient status of soils of the Lusikisiki area, Eastern Cape Province

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C. Bühmann --- , D.J. Beukes --- , D.P. Turner --- ,

    The aim of the paper is to Identify major soil plant fertility constraints for 15 soil profiles from the Lusikisiki area of the Eastern Cape Province of South Africa. Phosphorus levels were very low, with 87% of the A horizons...

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34. 

    The effects of strategic nitrogen fertiliser application during the cool season on perennial ryegrass-white clover pastures in the Western Cape Province 4. Selected nutritive characteristics and mineral content

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. Labuschagne --- , South Africa M.B. Hardy --- Department of Agriculture Western Cape, South Africa G.A. Agenbag --- , South Africa

    The influence of a single application of fertiliser N (0, 50, 100 and 150 kg N ha−1) applied in either autumn, early winter, late winter, early spring or late spring on selected nutritive and mineral parameters of a perennial ryegrass-white...

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35. 

    Extractable soil phosphorus threshold values for dryland maize on the South African Highveld

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C. J.J. Schmidt --- , South Africa F.G. Adriaanse --- , South Africa C.C. du Preez --- Department of Soil, Crop and Climate Sciences, South Africa

    The principle objective of this study was to establish P fertilizer guidelines for dryland maize on the South African Highveld according to the sufficiency concept of soil extractable P. Data sets from nine different P fertilizer trials at various localities...

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36. 

    Relations between phosphorus retention parameters and some other properties of benchmark soils in Lesotho

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S.F. Molete --- Department of Soil, Crop and Climate Sciences, South Africa C.C. du Preez --- Department of Soil, Crop and Climate Sciences, South Africa M.V. Marake --- , Lesotho

    The benchmark soils of Lesotho are characterized by high P retention and this aspect should be accommodated in fertilization programmes. This together with long procedures for determination of P retention parameters and a lack of information on the relations between...

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37. 

    Long-term kinetics of phosphate desorption from soil and its relationship with plant growth

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.M. Taddesse --- , Republic of South Africa A.S. Claassens --- , Republic of South Africa P.C. de Jager --- , Republic of South Africa

    Knowledge on the availability of residual P in soils is of great importance for fertilization management. The use of dialysis membrane tubes filled with hydrous ferric oxide solution has recently been reported as an effective way to characterize P desorption...

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38. 

    Obtaining the parameters required to model labile phosphorus for South African soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M. Van der Laan --- Department of Plant Production and Soil Science, South Africa J.G. Annandale --- Department of Plant Production and Soil Science, South Africa C.C. du Preez --- Department of Soil, Crop and Climate Sciences, South Africa S.A. Lorentz --- , South Africa

    Modelling phosphorus (P) in the environment can increase our understanding of potential transfer pathways into receiving water bodies as well as the plant availability of this nutrient in soil. Many current models make use of algorithms originally developed for the...

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39. 

    Yield and quality response of rose geranium (Pelargonium graveolens L.) to sulphur and phosphorus application

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: MM Sedibe --- School of Environmental Health and Agriculture, South Africa J Allemann --- Department of Soil, Crop and Climate Sciences, South Africa

    Sulphur and phosphorus are essential plant macronutrients. Sulphur is involved in the formation of chlorophyll, activation of enzymes and is part of coenzyme A. Phosphorus forms part of the structure of nucleic acids and phospholipids. Two separate studies were conducted...

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40. 

    PRELIMINARY RESULTS ON THE UPTAKE AND RELEASE OF 32_P BY POTAMOGETON PECTINATUS

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.H. Swanepoel --- , South Africa J.F. Vermaak --- , South Africa

    The absorption and release of 32PO4, by Potamogeton pectinatus L during winter was investigated using a partitioned container in which the roots were separated from the stems and leaves. 32PO4 is absorbed by the roots as well as the stems...

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41. 

    SOME ASPECTS OF THE DISTRIBUTION OF REACTIVE PHOSPHORUS IN LAKE McILWAINE, RHODESIA: PHOSPHORUS LOADING AND SEASONAL RESPONSES

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.A. Thornton --- Hydrobiology Research Unit,

    Between November 1976 and September 1977, samples were taken on a fortnightly basis from a representative station in Lake McIlwaine. In addition an intensive study of the riverine input of reactive phosphorus was conducted. Samples were analysed for total reactive...

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42. 

    SOME ASPECTS OF THE DISTRIBUTION OF REACTIVE PHOSPHORUS IN LAKE McILWAINE, RHODESIA: PHOSPHORUS LOADING AND ABIOTIC RESPONSES

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.A. Thornton --- Hydrobiology Research Unit, Zimbabwe-Rhodesia

    This study was designed to investigate the apparent loss from the water column in Lake McIlwaine This study of significant quantities of reactive phosphorus. The Total Reactive Phosphorus mass-balance for the lake for 1977/78 was calculated, and both in situ...

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43. 

    PHOSPHORUS DYNAMICS IN THE MONIMOLIMNION OF SWARTVLEI

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: M.J. Silberbauer --- , South Africa

    The exchange of phosphorus between the bottom sediment and monimolimnion of Swartvlei, a meromictic, humic lake, was investigated during the last three months of 1980. The concentrations of oxygen, dissolved salts, phosphorus and Fe++ in the water column were monitored,...

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44. 

    A PRELIMINARY ASSESSMENT OF THE IMPACT OF SOME ASPECTS OF THE HARTBEESPOORT DAM ENVIRONMENT ON PRODUCTION OF THE MAJOR FISH SPECIES

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: K.L. Cochrane --- , South Africa

    The dominant species of fish in Hartbeespoort Dam, in terms of mass composition of catches, are shown to be Oreochromis mossambicus (Peters), Cyprinus carpio Linnaeus and Clarias gariepinus Burchell. Minimum winter temperatures are demonstrated to have a major impact on...

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45. 

    NUTRIENTS IN AQUATIC ECOSYSTEMS: AN INTRODUCTION TO SIMILARITIES BETWEEN FRESHWATER AND MARINE ECOSYSTEMS

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: P Chapman --- , South Africa JA Thornton --- , South Africa

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46. 

    NUTRIENTS IN AFRICAN LAKE ECOSYSTEMS: DO WE KNOW ALL?

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.A. Thornton --- , South Africa

    It is nearly sixty years since the first studies were undertaken on the nutrient chemistry of African lakes. There have been numerous studies on the chemical composition of African waters in the intervening years. Yet as recently as five years...

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47. 

    NUTRIENT CYCLING IN MARINE ECOSYSTEMS

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: P. Chapman --- , South Africa

    The overall cycles of nitrogen, phosphorus and silicon in the sea are described and compared. Data on the fluxes and rates of change between various pools of each nutrient are given, where available, and gaps in knowledge are pointed out...

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48. 

    THE USE OF TROFIC AS AN AID FOR THE MANAGEMENT OF EUTROPHIC LAKES

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: K. Clarke --- , A.C. Jarvis --- , P.J. Ashton --- , T. Zohary --- ,

    As a result of eutrophication studies that have been performed by the National Institute for Water Research for many years it was decided in 1980 that a detailed investigation into this area take place. Hypertrophic Hartbeespoort Dam was selected as...

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49. 

    APPLICATION OF LAVSOE, AN EUTROPHICATION MODEL, TO BLOEMHOF DAM

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.N. Rossouw --- ,

    In 1985 the Department of Water Affairs introduced an effluent phosphate standard of 1 mg l−1 (as P) in seven potentially sensitive catchments. Although this is an uniform standard, permits can be granted for effluents to exceed the standard in...

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50. 

    Using faecal profiling to assess the effects of different management types on diet quality in semi-arid savanna

    Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: KR Mbatha D Ward

    We used faecal profiling to assess diet quality of animals under three different management types in a semi-arid savanna, northwest of Kimberley, Northern Cape, South Africa. The levels of faecal crude protein (FCP) and faecal phosphorus (FP) of free-ranging springbok...

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51. 

    Determining spatial and temporal variability in quantity and quality of vegetation for estimating the predictable sustainable stocking rate in the semi-arid savanna

    Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: KR Mbatha D Ward

    This study assessed the importance of spatial and temporal variation in plant quality and quantity for determining sustainable stocking rates in game, commercial and communal ranches in semi-arid savanna of the Northern Cape Province, South Africa, in wet and dry...

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52. 

    Soil characteristics under legume and non-legume tree canopies in signalgrass (Brachiaria decumbens) pastures

    Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Jose CB Dubeux --- North Florida Research and Education Center, USA Mario de Andrade Lira --- Instituto Agronômico de Pernambuco (IPA), Brazil Mercia V Ferreira dos Santos --- Zootecnia, Brazil Jim Muir --- Borlaug Institute, South Africa Monica A da Silva --- Zootecnia, Brazil Vicente I Teixeira --- Zootecnia, Brazil Alexandre C Leão de Mello --- Zootecnia, Brazil

    Tree canopies can change soil environments. Our study looked at soils 10%, 50%, 100% and 150% the distance from tree trunk to canopy edge of leguminous sabiá (Mimosa caesalpiniifolia Benth.) and espinheiro (Machaerium aculeatum Raddi) and non-legume cajueiro (Anacardium occidentale...

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53. 

    The effect of long-term mowing and ungulate exclusion on grass species composition and soil nutrient status on the Athi-Kapiti plains, central Kenya

    Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: D. Berliner J. Kioko

    The long-term (>30 years) impacts of mowing (for hay-making) and ungulate exclusion, on natural, unfertilised rangelands were investigated. Changes in grass species composition and soil nutrient status were measured The study site, situated on the Athi-Kapiti plains of central Kenya,...

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54. 

    Towards the assessment of the trophic status of South African impoundments for management purposes: Bon Accord Dam

    Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CE van Ginkel BC Hohls E Vermaak

    The 1 mg/l phosphate effluent standard legislated in South Africa in 1980 in seven sensitive catchments, and ad hoc eutrophication-related requests, necessitated the monitoring of 53 impoundments throughout the country. Variables that were monitored, and are still being monitored in...

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55. 

    Phosphorus sorption characteristics of sediment in the Simiyu and Kagera River basins: implications for phosphorus loading into Lake Victoria

    Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RA Tamatamah

    As part of a larger study to assess the influence of land use on riverine and atmospheric phosphorus (P) loading to Lake Victoria, P sorption characteristics of eight composite bottom sediment samples from the Simiyu and Kagera rivers were determined...

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56. 

    Toxicity of the chlorpyrifos-based pesticide Termifos^®: effects on behaviour and biochemical and haematological parameters of African catfish Clarias gariepinus

    Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CD Nwani --- Department of Zoology and Environmental Biology, Nigeria DO Ugwu --- Department of Zoology and Environmental Biology, Nigeria OC Okeke --- Department of Zoology and Environmental Biology, Nigeria GC Onyishi --- Department of Zoology and Environmental Biology, Nigeria FN Ekeh --- Department of Zoology and Environmental Biology, Nigeria C Atama --- Department of Zoology and Environmental Biology, Nigeria LO Eneje --- Department of Applied Microbiology and Brewing, Nigeria

    The present study, conducted in 2012, determined the toxicity of the chlorpyrifos-based pesticide Termifos® and its effects on behaviour and biochemical and haematological parameters in juvenile African catfish Clarias gariepinus. The 96 h LC50, estimated by probit analysis in a...

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57. 

    Phytoplankton community and physico-chemical seasonality and changes in Lake Hora-Kilole, Ethiopia, a tropical crater lake

    Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: R Abate --- Fisheries and Aquatic Sciences Stream, Department of Zoological Sciences, Ethiopia D Kifle --- Fisheries and Aquatic Sciences Stream, Department of Zoological Sciences, Ethiopia B Lemma --- Fisheries and Aquatic Sciences Stream, Department of Zoological Sciences, Ethiopia YH Gao --- School of Life Sciences, China

    Phytoplankton community structure and physico-chemical variables, sampled monthly at an offshore station in Lake Hora-Kilole from August 2007 to May 2008, were compared with previously reported data. In 1989 the Mojo River was temporarily diverted to flow into the lake...

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58. 

    THE USE OF TROFIC AS AN AID FOR THE MANAGEMENT OF EUTROPHIC LAKES

    Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: K. Clarke --- , A.C. Jarvis --- , P.J. Ashton --- , T. Zohary --- ,

    As a result of eutrophication studies that have been performed by the National Institute for Water Research for many years it was decided in 1980 that a detailed investigation into this area take place. Hypertrophic Hartbeespoort Dam was selected as...

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59. 

    APPLICATION OF LAVSOE, AN EUTROPHICATION MODEL, TO BLOEMHOF DAM

    Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: J.N. Rossouw --- ,

    In 1985 the Department of Water Affairs introduced an effluent phosphate standard of 1 mg l−1 (as P) in seven potentially sensitive catchments. Although this is an uniform standard, permits can be granted for effluents to exceed the standard in...

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60. 

    Responses of Eucalyptus species to fertilizer applications made at planting on granitic parent materials in the Mpumalanga and Northern Provinces of South Africa

    Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: ColleenA. Carlson --- , South Africa Ross Allan --- , South Africa Samuel Soko --- , South Africa

    Early research trials in South Africa have shown that Eucalyptus species generally respond positively to the addition of nutrients at planting. However, as most of these research trials were located in KwaZulu-Natal, it was important to investigate the nature ofthe...

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61. 

    Phosphorus fertiliser source and weed control effects on growth of three-year-old second-rotation Pinus radiata on Orthic Pumice soil in New Zealand

    Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: AA Rivaie --- , Indonesia P Loganathan --- Soil and Earth Sciences, Institute of Natural Resources, New Zealand

    Little information is available on the interactive effects of soluble and less-soluble phosphorus (P) fertilisers and weed control on growth and P nutrition of second-rotation Pinus radiata plantations. A study was initiated on three-year-old second-rotation P. radiata and to determine...

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62. 

    Effect of an impoundment on nutrient dynamics in the Kihansi River, Tanzania

    Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RJ Ideva J Machiwa F Schiemer T Hein

    The impact of the Kihansi Dam on electrical conductivity, pH, temperature and dissolved oxygen in the Kihansi River was assessed in 2005 after 85% of the original river flow had been diverted to the Lower Kihansi power plant. The results...

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63. 

    Seasonal nutrient fluctuation in selected plant species in the Kalahari

    Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: FH Stapelberg MW van Rooyen J du P Bothma

    Seasonal changes in crude protein, phosphorus and calcium contents of five common plant species in the south-western Kalahari were investigated. Three species that are browsed by springbok (Acacia erioloba, Grewia flava and Rhigozum trichotomum) and two grass species (Schmidtia kalahariensis...

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64. 

    Nitrogen fixation of Acacia mangium Willd. from two seed sources grown at different levels of phosphorus in an Ultisol, South Sumatra, Indonesia

    Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: M Gunawan Wibisono --- School of Plant Biology, Australia Erik Veneklaas --- School of Plant Biology, Australia Daniel S Mendham --- CSIRO Ecosystem Sciences, Australia Eko B Hardiyanto --- Faculty of Forestry, Indonesia

    Phosphorus (P) is required to facilitate the fixation of atmospheric nitrogen (N) by leguminous species such as Acacia mangium. We studied the N fixation of A. mangium trees grown from two seed sources. These consisted of bulk seedlots collected from...

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65. 

    A critical view on the soil fertility status of minimum-till kikuyu–ryegrass pastures in South Africa

    Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Pieter A Swanepoel --- Department of Agronomy, South Africa Chris C du Preez --- Soil, Crop and Climate Sciences, South Africa Philip R Botha --- Research and Technology Development Services, Department of Agriculture Western Cape, South Africa Hennie A Snyman --- Animal, Wildlife and Grassland Sciences, South Africa

    Cultivated pastures provide increased productivity and contribute inter alia to food security. Rangelands in the southern Cape region of South Africa have had a low animal production potential and were therefore improved through time as cultivated pastures. Initially, annual pastures...

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66. 

    Relationship between plant growth and organic acid exudates from ectomycorrhizal and non-ectomycorrhizal Pinus patula

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Rasheed Adeleke --- Department of Microbiology and Plant Pathology, South Africa T Eugene Cloete --- Department of Microbiology and Plant Pathology, South Africa Annick Bertrand --- Soil and Crops Research and Development Centre, Canada Damase P Khasa --- Centre for Forest Research and Institute of Integrative and Systems Biology, Canada

    Plant–mycorrhizal interaction is an important association in the ecosystem with significant impacts on the physical, biological and chemical properties of the soil. In the present study, potential relationships that exist between organic acid production by ectomycorrhizal pine seedlings and plant...

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67. 

    Changes in the algal composition and water quality of the Sundays River, Karoo, South Africa, from source to estuary

    Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: S Janse van Vuuren --- Unit for Environmental Sciences and Management, South Africa JC Taylor --- Unit for Environmental Sciences and Management, South Africa

    A first survey was done on algae present in the Sundays River from its source to its confluence with the sea. Species found in the upstream sections of the river included indicators of good water quality, but the quality deteriorated...

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68. 

    Riverine influence determines nearshore heterogeneity of nutrient (C, N, P) content and stoichiometry in the KwaZulu-Natal Bight, South Africa

    Item type: Journal Article • Journal: African Journal of Marine Science • Authors: UM Scharler --- School of Life Sciences, South Africa MJ Ayers --- School of Life Sciences, South Africa AM de Lecea --- School of Life Sciences, South Africa M Pretorius --- Department of Biodiversity and Conservation Biology, South Africa ST Fennessy --- Oceanographic Research Institute, South Africa JA Huggett --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa CF MacKay --- Oceanographic Research Institute, South Africa D Muir --- Medgar Evers College, USA

    Riverine influences on nearshore oceanic habitats often have detrimental consequences leading to algal blooms and hypoxia. In oligo- to mesotrophic systems, however, nutrient delivery via rivers may stimulate production and even be a vital source of nutrients, as may nutrient...

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69. 

    Trophic state and nutrient limitation in Lake Baringo, Kenya

    Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: EO Okech --- Department of biological sciences, Kenya N Kitaka --- Department of biological sciences, Kenya SO Oduor --- Department of biological sciences, Kenya D Verschuren --- Department of Biology, Belgium

    The trophic state of Lake Baringo and factors that could be limiting the development of algal biomass in it were investigated during one wet/dry hydrological cycle in 2014–2015. Water samples were analysed for dissolved inorganic nutrients, including , and ,...

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70. 

    Efforts Toward Improving Maize Yields on Smallholder Farms in Uasin Gishu County, Kenya, through Site-specific, Soil-testing-based Fertiliser Recommendations: A Transdisciplinary Approach

    Item type: Journal Article • Journal: East African Agricultural and Forestry Journal • Authors: Arusey Chebet --- University of Eldoret, Kenya Njoroge Ruth --- University of Eldoret, Kenya Otinga A. Nekesa --- University of Eldoret, Kenya Wilson Ng’etich --- University of Eldoret, Kenya Koech Julius --- University of Eldoret, Kenya Roland W. Scholz --- Danube University, Austria

    This study evaluated the effects of site-specific, soil-testing-based fertiliser recommendations on maize yields using the transdisciplinary (TD) process. The TD process utilizes knowledge from science and practice. Farmers, extension officers, local financial institutions, and other practitioners collaborated with local scientists...

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71. 

    Assessing legumes indigenous to South Africa, Lesotho and Swaziland for their pasture potential

    Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Marike Trytsman --- Agricultural Research Council–Animal Production, South Africa Elizabeth L Masemola --- Agricultural Research Council–Animal Production, South Africa Francuois L Müller --- Agricultural Research Council–Animal Production, South Africa Frikkie J Calitz --- Agricultural Research Council–Central Office (Biometry Services), South Africa Abraham E van Wyk --- Department of Plant and Soil Sciences, South Africa

    In contrast to the exploration and use of southern African grass plant genetic resources over the past century, only a few indigenous legume species are currently used as forages, notwithstanding the vast untapped legume diversity available in southern Africa. The...

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72. 

    Relationships between commonly-used South African and international soil phosphorus extraction tests on pristine and cultivated soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: VG White --- , South Africa AG Hardie --- , South Africa PJ Raath --- , South Africa

    The availability of soil phosphorus (P) norms for various plant available P tests is limited due to the cost of establishing these norms. Consequently a need exists for a means of converting between the values of commonly used South-African and...

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73. 

    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, Australia

    Forest 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...

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74. 

    Improving productivity of orange-fleshed sweetpotato (Ipomoea batatas) through intercropping with legumes and moderate phosphorus application

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Eliah Munda --- International Potato Center, Mozambique Petrus J Pieterse --- Department of Agronomy, South Africa Maria I Andrade --- International Potato Center, Mozambique Godwill S Makunde --- International Potato Center, Mozambique Engil I Pereira --- School of Earth, Environmental, and Marine Sciences, USA

    Sweetpotato yield is adversely affected by poor soil fertility in Mozambique where access to inorganic fertilisers is lacking. The objective of the study was to evaluate the effectiveness of intercropping sweetpotato with groundnut and soybean at various phosphorus (P) fertilisation...

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75. 

    Comparison of soil phosphorus fractions after 37 years of wheat production under different management practices in a semi-arid climate

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: K Ncoyi --- , South Africa CC du Preez --- , South Africa E Kotzé --- , South Africa

    Crop residue management is important for enhancing soil fertility and productivity which leads to an increase in crop yields. A long-term trial, situated near Bethlehem in the Eastern Free State in South Africa, was established to determine the influence of...

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76. 

    Phosphorus availability and fractions in a humic soil amended with poultry manure and lime

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: NP Mkhonza --- , South Africa NN Buthelezi-Dube --- , South Africa P Muchaonyerwa --- , South Africa

    Phosphorus (P) availability in highly weathered soils is limited. The objective of this study was to determine the effects of poultry manure (PM) and lime on P availability in humic soils. The soils were amended with lime and PM, separately...

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77. 

    Mixed-species plantations of Eucalyptus and Acacia mangium increase labile carbon and phosphorus levels in Ferralsol soils in the Cerrado biome, Brazil

    Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Wilbert Valkinir Cabreira --- , Brazil Marcos Gervasio Pereira --- , Brazil Fabiano de Carvalho Balieiro --- , Brazil Eduardo da Silva Matos --- , Brazil Renato de Aragão Ribeiro Rodrigues --- , Brazil Raissa Nascimento dos Santos --- , Brazil

    In order to clarify the effect of mixed planting in the dynamics of phosporus (P), we assessed the fractions of this element in mixed plantings of Eucalyptus urophylla × E. grandis (Urograndis) and Acacia mangium in a tropical soil clay,...

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78. 

    Effects of egg shell meal on the performance and haematology of layers and their egg quality

    Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Uchele Okpanachi --- , Nigeria Khalid Aliyu Yusuf --- , Nigeria Maryann Kehinde Ikubaje --- , Nigeria Gift Cincin Amaje Okpanachi --- , Nigeria

    In an attempt to achieve Sustainable Development Goals numbers one and two, eggshell meal was incorporated into layers diets to replace bone meal. Seventy-two point of lay birds were utilized in a nine-week experiment. Four experimental diets were formulated consisting...

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79. 

    Residual fertiliser and liming impacts in a long-term Acacia mearnsii trial

    Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Louis Titshall --- , South Africa

    Sixth rotation growth measurements of an Acacia mearnsii fertiliser trial established to test the effect of nitrogen (N), phosphorus (P), potassium (K) and lime application on growth and bark production, showed that residual P and lime effects are present. First...

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80. 

    Phosphorus extraction by selected methods in alkaline and calcareous soils after mono-ammonium phosphate application at different rates

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: AE Venter --- , South Africa CC du Preez --- , South Africa

    Little research has been done on extractable phosphorus (P) in alkaline and calcareous irrigated soils of South Africa. This study aimed to quantify extractable P by selected methods in these soils after application of mono-ammonium phosphate (MAP) at different rates...

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81. 

    A comparison of the results of phosphorus analyses of alkaline and calcareous soils amongst South African laboratories

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: AE Venter --- , South Africa CC du Preez --- , South Africa

    Large areas of alkaline and calcareous soils are irrigated in South Africa. For these soils, proper fertilisation programs based on soil phoshorus (P) analyses are required. Little is known about P analyses of alkaline and calcareous soils. The study aimed...

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82. 

    Influence of cropping sequences on labile carbon and phosphorus fractions in a wheat-based conservation agriculture system

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: NZ Sosibo --- , South Africa E Dube --- , South Africa P Muchaonyerwa --- , South Africa TJ Tsilo --- , South Africa

    While conservation agriculture (CA) has largely been successful in many areas, some reports suggest that certain farmers have not realised the benefits they had hoped for, especially in Africa. The benefits of CA could depend on the cropping sequences involved...

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83. 

    Impact of liming on extractable phosphorus, exchangeable base cations, and effective cation exchange capacity of eastern Free State soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: HJJ van Zyl --- University of the Free State, South Africa CC du Preez --- University of the Free State, South Africa

    Soil acidity can adversely affect wheat production in the eastern Free State, South Africa. Liming of the soils is therefore essential. The aim of this study was to establish whether extractable phosphorus (P), exchangeable calcium (Ca), magnesium (Mg) and potassium...

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84. 

    Genotypic variability in nutrient uptake and use efficiency in chickpea grown under low phosphorus availability in a Mediterranean climate

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Hanine Loucif --- Université Djilali Bounaama de Khemis Miliana, Algeria Brahim Bousalhih --- Université Djilali Bounaama de Khemis Miliana, Algeria Rebiha Chaoui --- Université Djilali Bounaama de Khemis Miliana, Algeria Jean Jacques Drevon --- Université de Montpellier, France Mohamed Farissi --- Sultan Moulay Slimane University, Morocco Mohamed Lazali --- Université Djilali Bounaama de Khemis Miliana, Algeria

    Low phosphorus (P) availability is a major constraint for chickpea production. Consequently, P-efficient genotypes can improve productivity under conditions where the higher application of P is not economical. This study was conducted to characterise four chickpea genotypes for nutrient uptake...

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85. 

    Effects of short-duration kraaling depend on initial conditions in a mesic grassland

    Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Heidi-Jayne Hawkins --- , South Africa Nompendulo Mgwali --- , South Africa Susanne Vetter --- Rhodes University, South Africa

    Short-duration overnight kraaling has been suggested as a tool for restoring degraded rangelands. However, the response of different plant functional types and communities to such intense livestock impact may vary depending on local context. We thus examined the effects of...

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86. 

    Phosphorus sorption kinetics in calcareous soils of selected arid and semi-arid toposequences and its relationship with plant growth

    Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. Jafari --- Department of Soil Science, College of Agriculture, Isfahan University of Technology, Iran H. Shariatmadari --- Department of Soil Science, College of Agriculture, Isfahan University of Technology, Iran Y. Rezainejad --- Department of Soil Science, College of Agriculture, Isfahan University of Technology, Iran Sh. Ghalami --- Department of Soil Science, College of Agriculture, Isfahan University of Technology, Iran

    An array of kinetic equations has been used to describe time-dependent sorption of P by soils. We investigated P sorption kinetics in calcareous soils at upper-, mid-, and lowerslope positions of two arid and two semi-arid landscapes and its relationship...

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