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ptfkit.myeni2021

ptfkit.myeni2021

Gravimetric field capacity and permanent wilting point for South African soils.

Reference

Myeni, L., Mdlambuzi, T., Paterson, D. G., De Nysschen, G., & Moeletsi, M. E. (2021). Development and evaluation of pedotransfer functions to estimate soil moisture content at field capacity and permanent wilting point for South African soils. Water, 13(19), 2639. https://doi.org/10.3390/w13192639 DOI: 10.3390/w13192639

Territory

South Africa.

Dataset

ARC national soil database: 6307 soil horizons retained after quality control, with 3171 development horizons and 3136 validation horizons. Horizons were grouped regardless of depth, soil type, textural class, geographic location and climate, then randomly split per granulometric range (Sections 2.1-2.2; Tables 2-3).

FUNCTION DESCRIPTION
calc_ptf_myeni2021_fc

Estimate gravimetric field capacity from clay, silt and soil organic carbon.
calc_ptf_myeni2021_pwp

Estimate gravimetric permanent wilting point from clay, silt and soil organic carbon.

calc_ptf_myeni2021_fc 

calc_ptf_myeni2021_fc(*, clay: float, silt: float, soc: float) -> floating

calc_ptf_myeni2021_fc(*, clay: ArrayLike, silt: ArrayLike, soc: ArrayLike, out: NDArray[floating] | None = None) -> NDArray[floating]

Estimate gravimetric field capacity from clay, silt and soil organic carbon.

PARAMETER DESCRIPTION
clay

Clay content by weight, particle diameter below 0.002 mm. (%)

TYPE: float | ArrayLike

silt

Silt content by weight, particle diameter 0.002-0.05 mm. (%)

TYPE: float | ArrayLike

soc

Soil organic carbon content by weight, measured by the Walkley-Black method. (%)

TYPE: float | ArrayLike

out

Optional output arrays for in-place calculation.

TYPE: NDArray[floating] | None DEFAULT: None

RETURNS DESCRIPTION
fc

Gravimetric soil moisture content at field capacity (-33 kPa). (kg kg⁻¹)

TYPE: floating | NDArray[floating]

Notes

Prediction target: Gravimetric soil moisture content at field capacity (-33 kPa). Table 5 gives the stepwise multiple linear regression for FC. Inputs are weight percentages; output is gravimetric water content.

Warning

Apply with caution outside South Africa, even under similar soil and climatic conditions. Disturbed samples were used; soil structure is not explicitly represented.

Source code in ptfkit/myeni2021.py 
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def calc_ptf_myeni2021_fc(
    *,
    clay: float | ArrayLike,
    silt: float | ArrayLike,
    soc: float | ArrayLike,
    out: NDArray[floating] | None = None,
) -> floating | NDArray[floating]:
    """Estimate gravimetric field capacity from clay, silt and soil organic carbon.

    Arguments:
        clay: Clay content by weight, particle diameter below 0.002 mm. (%)
        silt: Silt content by weight, particle diameter 0.002-0.05 mm. (%)
        soc: Soil organic carbon content by weight, measured by the Walkley-Black method. (%)
        out: Optional output arrays for in-place calculation.

    Returns:
        fc: Gravimetric soil moisture content at field capacity (-33 kPa). (kg kg⁻¹)

    Notes:
        Prediction target: Gravimetric soil moisture content at field capacity (-33 kPa).
        Table 5 gives the stepwise multiple linear regression for FC.
        Inputs are weight percentages; output is gravimetric water content.

    Warning:
        Apply with caution outside South Africa, even under similar soil and climatic conditions.
        Disturbed samples were used; soil structure is not explicitly represented.

    """
    return _call(
        _calc_ptf_myeni2021_fc,
        clay,
        silt,
        soc,
        out=out,
    )

calc_ptf_myeni2021_pwp 

calc_ptf_myeni2021_pwp(*, clay: float, silt: float, soc: float) -> floating

calc_ptf_myeni2021_pwp(*, clay: ArrayLike, silt: ArrayLike, soc: ArrayLike, out: NDArray[floating] | None = None) -> NDArray[floating]

Estimate gravimetric permanent wilting point from clay, silt and soil organic carbon.

PARAMETER DESCRIPTION
clay

Clay content by weight, particle diameter below 0.002 mm. (%)

TYPE: float | ArrayLike

silt

Silt content by weight, particle diameter 0.002-0.05 mm. (%)

TYPE: float | ArrayLike

soc

Soil organic carbon content by weight, measured by the Walkley-Black method. (%)

TYPE: float | ArrayLike

out

Optional output arrays for in-place calculation.

TYPE: NDArray[floating] | None DEFAULT: None

RETURNS DESCRIPTION
pwp

Gravimetric soil moisture content at permanent wilting point (-1500 kPa). (kg kg⁻¹)

TYPE: floating | NDArray[floating]

Notes

Prediction target: Gravimetric soil moisture content at permanent wilting point (-1500 kPa). Table 5 gives the stepwise multiple linear regression for PWP without an additive constant. Inputs are weight percentages; output is gravimetric water content.

Warning

Apply with caution outside South Africa, even under similar soil and climatic conditions. Disturbed samples were used; soil structure is not explicitly represented.

Source code in ptfkit/myeni2021.py 
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def calc_ptf_myeni2021_pwp(
    *,
    clay: float | ArrayLike,
    silt: float | ArrayLike,
    soc: float | ArrayLike,
    out: NDArray[floating] | None = None,
) -> floating | NDArray[floating]:
    """Estimate gravimetric permanent wilting point from clay, silt and soil organic carbon.

    Arguments:
        clay: Clay content by weight, particle diameter below 0.002 mm. (%)
        silt: Silt content by weight, particle diameter 0.002-0.05 mm. (%)
        soc: Soil organic carbon content by weight, measured by the Walkley-Black method. (%)
        out: Optional output arrays for in-place calculation.

    Returns:
        pwp: Gravimetric soil moisture content at permanent wilting point (-1500 kPa). (kg kg⁻¹)

    Notes:
        Prediction target: Gravimetric soil moisture content at permanent wilting point (-1500 kPa).
        Table 5 gives the stepwise multiple linear regression for PWP without an additive constant.
        Inputs are weight percentages; output is gravimetric water content.

    Warning:
        Apply with caution outside South Africa, even under similar soil and climatic conditions.
        Disturbed samples were used; soil structure is not explicitly represented.

    """
    return _call(
        _calc_ptf_myeni2021_pwp,
        clay,
        silt,
        soc,
        out=out,
    )