Articles by Keyword: Cec Estimation Techniques

Search results for Cec Estimation Techniques

We found 36 results for you
  1. Estimation of minimum temperature on a mesoscale

    Estimation of minimum temperature on a mesoscale

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Working relationships between mean minimum temperatures and environmental factors by means of regression techniques were established and used to estimate temperatures at gridpoints. These estimated temperatures were then used with a computer package program to map the isotherms on a...
  2. Comparison of methods for estimating cation exchange capacity of orchard soils

    Comparison of methods for estimating cation exchange capacity of orchard soils

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Various methods for estimating soil cation exchange capacity (CEC) were compared. CEC obtained by the sum of extractable cations and the Adams-Evans buffer method were considerably higher than those obtained by saturation and displacement of either NH4 + or Na+...
  3. An Evaluation of the Use of “Gentan” Probabilities in Forestry Planning

    Item type: Journal Article • Journal: South African Forestry Journal
    An evaluation of Suzuki's concept of Gentan probabilities is presented. Model fitting is discussed in some detail. It is shown that the Gentan method is suitable only for forests that are at least close to normality.
  4. An ocular technique for estimating utilization of karoo bushes

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    A subjective technique for estimating utilization of karoo bushes is evaluated and guidelines for its use are proposed. Taking the average utilization from estimates on 30–40 bushes, 20% differences in utilization could be distinguished as significant ‐ even when different...
  5. Evaluation of the coefficients of the Ångström formula for the estimation of solar radiation in South Africa

    Evaluation of the coefficients of the Ångström formula for the estimation of solar radiation in South Africa

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    The regression coefficients of a modified Ångström formula, initially postulated as being constant under all climatic conditions, have with widespread use been shown to vary not only spatially but also due to variable sunshine duration conditions. Daily sunshine duration and...
  6. Estimating Class A pan evaporation at locations with sparse climatic data

    Estimating Class A pan evaporation at locations with sparse climatic data

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Class A pan evaporation was found to correlate closely with daylength-adjusted maximum daily air temperature (ATM), on a bimonthly basis. ATM and altitude were used as variables in a regression analysis to develop a series of evaporation-estimation equations for various...
  7. A multivariate approach to a specific problem of grouping maize cultivars

    A multivariate approach to a specific problem of grouping maize cultivars

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    The use of multivariate techniques in the analysis of multivariate problems is illustrated by comparing the results of univariate and multivariate techniques applied to the problem of establishing the nutritional requirements of, and the acid tolerance differences between maize cultivars...
  8. An attempt at estimating solar radiation at South African sites which measure air temperature only

    An attempt at estimating solar radiation at South African sites which measure air temperature only

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Daily potential surface radiation values were calculated for selected South African weather stations. These were used, together with various air temperature parameters, to derive regression equations to estimate actual surface solar radiation at sites lacking the required instrumentation. A single...
  9. Estimation of soil water retention from clay content and cation exchange capacity values of soils

    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
    Soil 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...
  10. Evaluating the maize production potential of a semi-arid ecotope with four production techniques

    Evaluating the maize production potential of a semi-arid ecotope with four production techniques

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Water conservation production techniques are needed to boost crop production in semi-arid areas. The in-field rainwater harvesting (IRWH) technique has been developed for this purpose, and found to be successful on clay and duplex soils, but has not yet been...