Skip to content

Moisture retention and plasticity regressions for two groups of Nigerian soils.

Source

Lal, R. (1979). Physical properties and moisture retention characteristics of some Nigerian soils. Geoderma, 21, 209-223.

DOI: 10.1016/0016-7061(78)90028-9

Scope

Territory: Nigeria

Dataset: 119 genetic-horizon samples from 23 profiles in two parent-material groups.

Functions

calc_ptf_lal1979_group_i_water_0bar_from_clay

Estimate gravimetric moisture retention at saturation for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at saturation

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_0bar g g⁻¹ Gravimetric moisture retention at saturation expressed per unit dry soil mass.

Note

Table IV, Group I, clay predictor, water_0bar response.

calc_ptf_lal1979_group_i_water_0bar_from_sand

Estimate gravimetric moisture retention at saturation for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at saturation

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_0bar g g⁻¹ Gravimetric moisture retention at saturation expressed per unit dry soil mass.

Note

Table IV, Group I, sand predictor, water_0bar response.

calc_ptf_lal1979_group_ii_water_0bar_from_clay

Estimate gravimetric moisture retention at saturation for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at saturation

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_0bar g g⁻¹ Gravimetric moisture retention at saturation expressed per unit dry soil mass.

Note

Table IV, Group II, clay predictor, water_0bar response.

calc_ptf_lal1979_group_ii_water_0bar_from_sand

Estimate gravimetric moisture retention at saturation for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at saturation

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_0bar g g⁻¹ Gravimetric moisture retention at saturation expressed per unit dry soil mass.

Note

Table IV, Group II, sand predictor, water_0bar response.

calc_ptf_lal1979_group_i_water_01bar_from_clay

Estimate gravimetric moisture retention at 0.1 bar suction for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 0.1 bar suction

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_01bar g g⁻¹ Gravimetric moisture retention at 0.1 bar suction expressed per unit dry soil mass.

Note

Table V, Group I, clay predictor, water_01bar response.

calc_ptf_lal1979_group_i_water_03bar_from_clay

Estimate gravimetric moisture retention at 0.3 bar suction for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 0.3 bar suction

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_03bar g g⁻¹ Gravimetric moisture retention at 0.3 bar suction expressed per unit dry soil mass.

Note

Table V, Group I, clay predictor, water_03bar response.

calc_ptf_lal1979_group_i_water_01bar_from_sand

Estimate gravimetric moisture retention at 0.1 bar suction for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 0.1 bar suction

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_01bar g g⁻¹ Gravimetric moisture retention at 0.1 bar suction expressed per unit dry soil mass.

Note

Table V, Group I, sand predictor, water_01bar response.

calc_ptf_lal1979_group_i_water_03bar_from_sand

Estimate gravimetric moisture retention at 0.3 bar suction for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 0.3 bar suction

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_03bar g g⁻¹ Gravimetric moisture retention at 0.3 bar suction expressed per unit dry soil mass.

Note

Table V, Group I, sand predictor, water_03bar response.

calc_ptf_lal1979_group_ii_water_01bar_from_clay

Estimate gravimetric moisture retention at 0.1 bar suction for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 0.1 bar suction

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_01bar g g⁻¹ Gravimetric moisture retention at 0.1 bar suction expressed per unit dry soil mass.

Note

Table V, Group II, clay predictor, water_01bar response.

calc_ptf_lal1979_group_ii_water_03bar_from_clay

Estimate gravimetric moisture retention at 0.3 bar suction for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 0.3 bar suction

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_03bar g g⁻¹ Gravimetric moisture retention at 0.3 bar suction expressed per unit dry soil mass.

Note

Table V, Group II, clay predictor, water_03bar response.

calc_ptf_lal1979_group_ii_water_01bar_from_sand

Estimate gravimetric moisture retention at 0.1 bar suction for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 0.1 bar suction

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_01bar g g⁻¹ Gravimetric moisture retention at 0.1 bar suction expressed per unit dry soil mass.

Note

Table V, Group II, sand predictor, water_01bar response.

calc_ptf_lal1979_group_ii_water_03bar_from_sand

Estimate gravimetric moisture retention at 0.3 bar suction for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 0.3 bar suction

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_03bar g g⁻¹ Gravimetric moisture retention at 0.3 bar suction expressed per unit dry soil mass.

Note

Table V, Group II, sand predictor, water_03bar response.

calc_ptf_lal1979_group_i_water_15bar_from_clay

Estimate gravimetric moisture retention at 15 bar suction for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 15 bar suction

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_15bar g g⁻¹ Gravimetric moisture retention at 15 bar suction expressed per unit dry soil mass.

Note

Table VI, Group I, clay predictor, water_15bar response.

calc_ptf_lal1979_group_i_water_15bar_from_sand

Estimate gravimetric moisture retention at 15 bar suction for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 15 bar suction

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_15bar g g⁻¹ Gravimetric moisture retention at 15 bar suction expressed per unit dry soil mass.

Note

Table VI, Group I, sand predictor, water_15bar response.

calc_ptf_lal1979_group_i_water_15bar_from_silt

Estimate gravimetric moisture retention at 15 bar suction for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 15 bar suction

Inputs

Name Type Unit Domain Description
silt number % Silt from 0.002 to 0.02 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_15bar g g⁻¹ Gravimetric moisture retention at 15 bar suction expressed per unit dry soil mass.

Note

Table VI, Group I, silt predictor, water_15bar response.

calc_ptf_lal1979_group_ii_water_15bar_from_clay

Estimate gravimetric moisture retention at 15 bar suction for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 15 bar suction

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_15bar g g⁻¹ Gravimetric moisture retention at 15 bar suction expressed per unit dry soil mass.

Note

Table VI, Group II, clay predictor, water_15bar response.

calc_ptf_lal1979_group_ii_water_15bar_from_sand

Estimate gravimetric moisture retention at 15 bar suction for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 15 bar suction

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
water_15bar g g⁻¹ Gravimetric moisture retention at 15 bar suction expressed per unit dry soil mass.

Note

Table VI, Group II, sand predictor, water_15bar response.

calc_ptf_lal1979_group_i_moisture_equivalent_from_clay

Estimate gravimetric moisture equivalent measured at 1000 times gravity for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture equivalent measured at 1000 times gravity

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
moisture_equivalent g g⁻¹ Gravimetric moisture equivalent measured at 1000 times gravity expressed per unit dry soil mass.

Note

Table VII, Group I, clay predictor, moisture_equivalent response.

calc_ptf_lal1979_group_i_moisture_equivalent_from_sand

Estimate gravimetric moisture equivalent measured at 1000 times gravity for Group I.

Status: ready-for-implementation

Prediction target: Gravimetric moisture equivalent measured at 1000 times gravity

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
moisture_equivalent g g⁻¹ Gravimetric moisture equivalent measured at 1000 times gravity expressed per unit dry soil mass.

Note

Table VII, Group I, sand predictor, moisture_equivalent response.

calc_ptf_lal1979_group_ii_moisture_equivalent_from_clay

Estimate gravimetric moisture equivalent measured at 1000 times gravity for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture equivalent measured at 1000 times gravity

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
moisture_equivalent g g⁻¹ Gravimetric moisture equivalent measured at 1000 times gravity expressed per unit dry soil mass.

Note

Table VII, Group II, clay predictor, moisture_equivalent response.

calc_ptf_lal1979_group_ii_moisture_equivalent_from_sand

Estimate gravimetric moisture equivalent measured at 1000 times gravity for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture equivalent measured at 1000 times gravity

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
moisture_equivalent g g⁻¹ Gravimetric moisture equivalent measured at 1000 times gravity expressed per unit dry soil mass.

Note

Table VII, Group II, sand predictor, moisture_equivalent response.

calc_ptf_lal1979_group_ii_moisture_equivalent_from_silt

Estimate gravimetric moisture equivalent measured at 1000 times gravity for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture equivalent measured at 1000 times gravity

Inputs

Name Type Unit Domain Description
silt number % Silt from 0.002 to 0.02 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
moisture_equivalent g g⁻¹ Gravimetric moisture equivalent measured at 1000 times gravity expressed per unit dry soil mass.

Note

Table VII, Group II, silt predictor, moisture_equivalent response.

calc_ptf_lal1979_group_i_water_01bar_from_water_0bar

Estimate gravimetric moisture retention at 0.1 bar suction for Group I.

Status: blocked

Prediction target: Gravimetric moisture retention at 0.1 bar suction

Inputs

Name Type Unit Domain Description
water_0bar number g/g Gravimetric moisture retention at 0 bar suction on disturbed soil.

Outputs

Name Unit Domain Description
water_01bar g g⁻¹ Gravimetric moisture retention at 0.1 bar suction expressed per unit dry soil mass.

Note

Table VIII, Group I, water_0bar predictor, water_01bar response.

Note

Printed regression slope m = 1.00; intercept b = 0.20.

Warning

Blocked: the printed dependent/independent labels and coefficients predict increasing water content with increasing suction. Confirm regression direction and intercept sign from authoritative evidence; no reversal or sign correction is assumed.

calc_ptf_lal1979_group_i_water_03bar_from_water_0bar

Estimate gravimetric moisture retention at 0.3 bar suction for Group I.

Status: blocked

Prediction target: Gravimetric moisture retention at 0.3 bar suction

Inputs

Name Type Unit Domain Description
water_0bar number g/g Gravimetric moisture retention at 0 bar suction on disturbed soil.

Outputs

Name Unit Domain Description
water_03bar g g⁻¹ Gravimetric moisture retention at 0.3 bar suction expressed per unit dry soil mass.

Note

Table VIII, Group I, water_0bar predictor, water_03bar response.

Note

Printed regression slope m = 1.05; intercept b = 0.22.

Warning

Blocked: the printed dependent/independent labels and coefficients predict increasing water content with increasing suction. Confirm regression direction and intercept sign from authoritative evidence; no reversal or sign correction is assumed.

calc_ptf_lal1979_group_i_water_15bar_from_water_0bar

Estimate gravimetric moisture retention at 15 bar suction for Group I.

Status: blocked

Prediction target: Gravimetric moisture retention at 15 bar suction

Inputs

Name Type Unit Domain Description
water_0bar number g/g Gravimetric moisture retention at 0 bar suction on disturbed soil.

Outputs

Name Unit Domain Description
water_15bar g g⁻¹ Gravimetric moisture retention at 15 bar suction expressed per unit dry soil mass.

Note

Table VIII, Group I, water_0bar predictor, water_15bar response.

Note

Printed regression slope m = 1.19; intercept b = 0.28.

Warning

Blocked: the printed dependent/independent labels and coefficients predict increasing water content with increasing suction. Confirm regression direction and intercept sign from authoritative evidence; no reversal or sign correction is assumed.

calc_ptf_lal1979_group_i_water_03bar_from_water_01bar

Estimate gravimetric moisture retention at 0.3 bar suction for Group I.

Status: blocked

Prediction target: Gravimetric moisture retention at 0.3 bar suction

Inputs

Name Type Unit Domain Description
water_01bar number g/g Gravimetric moisture retention at 0.1 bar suction on disturbed soil.

Outputs

Name Unit Domain Description
water_03bar g g⁻¹ Gravimetric moisture retention at 0.3 bar suction expressed per unit dry soil mass.

Note

Table VIII, Group I, water_01bar predictor, water_03bar response.

Note

Printed regression slope m = 1.05; intercept b = 0.10.

Warning

Blocked: the printed dependent/independent labels and coefficients predict increasing water content with increasing suction. Confirm regression direction and intercept sign from authoritative evidence; no reversal or sign correction is assumed.

calc_ptf_lal1979_group_ii_water_01bar_from_water_0bar

Estimate gravimetric moisture retention at 0.1 bar suction for Group II.

Status: blocked

Prediction target: Gravimetric moisture retention at 0.1 bar suction

Inputs

Name Type Unit Domain Description
water_0bar number g/g Gravimetric moisture retention at 0 bar suction on disturbed soil.

Outputs

Name Unit Domain Description
water_01bar g g⁻¹ Gravimetric moisture retention at 0.1 bar suction expressed per unit dry soil mass.

Note

Table VIII, Group II, water_0bar predictor, water_01bar response.

Note

Printed regression slope m = 0.94; intercept b = 0.238.

Warning

Blocked: the printed dependent/independent labels and coefficients predict increasing water content with increasing suction. Confirm regression direction and intercept sign from authoritative evidence; no reversal or sign correction is assumed.

calc_ptf_lal1979_group_ii_water_03bar_from_water_0bar

Estimate gravimetric moisture retention at 0.3 bar suction for Group II.

Status: blocked

Prediction target: Gravimetric moisture retention at 0.3 bar suction

Inputs

Name Type Unit Domain Description
water_0bar number g/g Gravimetric moisture retention at 0 bar suction on disturbed soil.

Outputs

Name Unit Domain Description
water_03bar g g⁻¹ Gravimetric moisture retention at 0.3 bar suction expressed per unit dry soil mass.

Note

Table VIII, Group II, water_0bar predictor, water_03bar response.

Note

Printed regression slope m = 0.91; intercept b = 0.281.

Warning

Blocked: the printed dependent/independent labels and coefficients predict increasing water content with increasing suction. Confirm regression direction and intercept sign from authoritative evidence; no reversal or sign correction is assumed.

calc_ptf_lal1979_group_ii_water_15bar_from_water_0bar

Estimate gravimetric moisture retention at 15 bar suction for Group II.

Status: blocked

Prediction target: Gravimetric moisture retention at 15 bar suction

Inputs

Name Type Unit Domain Description
water_0bar number g/g Gravimetric moisture retention at 0 bar suction on disturbed soil.

Outputs

Name Unit Domain Description
water_15bar g g⁻¹ Gravimetric moisture retention at 15 bar suction expressed per unit dry soil mass.

Note

Table VIII, Group II, water_0bar predictor, water_15bar response.

Note

Printed regression slope m = 1.45; intercept b = 0.277.

Warning

Blocked: the printed dependent/independent labels and coefficients predict increasing water content with increasing suction. Confirm regression direction and intercept sign from authoritative evidence; no reversal or sign correction is assumed.

calc_ptf_lal1979_group_ii_water_03bar_from_water_01bar

Estimate gravimetric moisture retention at 0.3 bar suction for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 0.3 bar suction

Inputs

Name Type Unit Domain Description
water_01bar number g/g Gravimetric moisture retention at 0.1 bar suction on disturbed soil.

Outputs

Name Unit Domain Description
water_03bar g g⁻¹ Gravimetric moisture retention at 0.3 bar suction expressed per unit dry soil mass.

Note

Table VIII, Group II, water_01bar predictor, water_03bar response.

calc_ptf_lal1979_group_ii_water_15bar_from_water_01bar

Estimate gravimetric moisture retention at 15 bar suction for Group II.

Status: ready-for-implementation

Prediction target: Gravimetric moisture retention at 15 bar suction

Inputs

Name Type Unit Domain Description
water_01bar number g/g Gravimetric moisture retention at 0.1 bar suction on disturbed soil.

Outputs

Name Unit Domain Description
water_15bar g g⁻¹ Gravimetric moisture retention at 15 bar suction expressed per unit dry soil mass.

Note

Table VIII, Group II, water_01bar predictor, water_15bar response.

calc_ptf_lal1979_group_i_upper_plastic_limit_from_organic_carbon

Estimate upper plastic limit for Group I.

Status: ready-for-implementation

Prediction target: Upper plastic limit

Inputs

Name Type Unit Domain Description
organic_carbon number % Organic carbon measured by Walkley and Black wet combustion; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
upper_plastic_limit % Upper plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group I, organic_carbon predictor, upper_plastic_limit response.

calc_ptf_lal1979_group_i_lower_plastic_limit_from_organic_carbon

Estimate lower plastic limit for Group I.

Status: ready-for-implementation

Prediction target: Lower plastic limit

Inputs

Name Type Unit Domain Description
organic_carbon number % Organic carbon measured by Walkley and Black wet combustion; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
lower_plastic_limit % Lower plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group I, organic_carbon predictor, lower_plastic_limit response.

calc_ptf_lal1979_group_i_plasticity_index_from_organic_carbon

Estimate plasticity index (upper minus lower plastic limit) for Group I.

Status: ready-for-implementation

Prediction target: Plasticity index (upper minus lower plastic limit)

Inputs

Name Type Unit Domain Description
organic_carbon number % Organic carbon measured by Walkley and Black wet combustion; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
plasticity_index % Plasticity index (upper minus lower plastic limit) expressed as percentage of oven-dry soil mass.

Note

Table IX, Group I, organic_carbon predictor, plasticity_index response.

calc_ptf_lal1979_group_i_upper_plastic_limit_from_clay

Estimate upper plastic limit for Group I.

Status: ready-for-implementation

Prediction target: Upper plastic limit

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
upper_plastic_limit % Upper plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group I, clay predictor, upper_plastic_limit response.

calc_ptf_lal1979_group_i_lower_plastic_limit_from_clay

Estimate lower plastic limit for Group I.

Status: ready-for-implementation

Prediction target: Lower plastic limit

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
lower_plastic_limit % Lower plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group I, clay predictor, lower_plastic_limit response.

calc_ptf_lal1979_group_i_plasticity_index_from_clay

Estimate plasticity index (upper minus lower plastic limit) for Group I.

Status: ready-for-implementation

Prediction target: Plasticity index (upper minus lower plastic limit)

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
plasticity_index % Plasticity index (upper minus lower plastic limit) expressed as percentage of oven-dry soil mass.

Note

Table IX, Group I, clay predictor, plasticity_index response.

calc_ptf_lal1979_group_i_upper_plastic_limit_from_sand

Estimate upper plastic limit for Group I.

Status: blocked

Prediction target: Upper plastic limit

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
upper_plastic_limit % Upper plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group I, sand predictor, upper_plastic_limit response.

Note

Printed regression slope m = -0.40; intercept b = -46.20.

Warning

Blocked: printed intercept -46.20 with slope -0.40 produces a negative upper plastic limit for nonnegative sand. Confirm the intercept sign; no correction is assumed.

calc_ptf_lal1979_group_i_lower_plastic_limit_from_sand

Estimate lower plastic limit for Group I.

Status: ready-for-implementation

Prediction target: Lower plastic limit

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
lower_plastic_limit % Lower plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group I, sand predictor, lower_plastic_limit response.

calc_ptf_lal1979_group_i_plasticity_index_from_sand

Estimate plasticity index (upper minus lower plastic limit) for Group I.

Status: ready-for-implementation

Prediction target: Plasticity index (upper minus lower plastic limit)

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
plasticity_index % Plasticity index (upper minus lower plastic limit) expressed as percentage of oven-dry soil mass.

Note

Table IX, Group I, sand predictor, plasticity_index response.

calc_ptf_lal1979_group_ii_upper_plastic_limit_from_organic_carbon

Estimate upper plastic limit for Group II.

Status: ready-for-implementation

Prediction target: Upper plastic limit

Inputs

Name Type Unit Domain Description
organic_carbon number % Organic carbon measured by Walkley and Black wet combustion; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
upper_plastic_limit % Upper plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group II, organic_carbon predictor, upper_plastic_limit response.

calc_ptf_lal1979_group_ii_plasticity_index_from_organic_carbon

Estimate plasticity index (upper minus lower plastic limit) for Group II.

Status: ready-for-implementation

Prediction target: Plasticity index (upper minus lower plastic limit)

Inputs

Name Type Unit Domain Description
organic_carbon number % Organic carbon measured by Walkley and Black wet combustion; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
plasticity_index % Plasticity index (upper minus lower plastic limit) expressed as percentage of oven-dry soil mass.

Note

Table IX, Group II, organic_carbon predictor, plasticity_index response.

calc_ptf_lal1979_group_ii_upper_plastic_limit_from_clay

Estimate upper plastic limit for Group II.

Status: ready-for-implementation

Prediction target: Upper plastic limit

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
upper_plastic_limit % Upper plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group II, clay predictor, upper_plastic_limit response.

calc_ptf_lal1979_group_ii_lower_plastic_limit_from_clay

Estimate lower plastic limit for Group II.

Status: ready-for-implementation

Prediction target: Lower plastic limit

Inputs

Name Type Unit Domain Description
clay number % Clay smaller than 0.002 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
lower_plastic_limit % Lower plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group II, clay predictor, lower_plastic_limit response.

calc_ptf_lal1979_group_ii_upper_plastic_limit_from_sand

Estimate upper plastic limit for Group II.

Status: ready-for-implementation

Prediction target: Upper plastic limit

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
upper_plastic_limit % Upper plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group II, sand predictor, upper_plastic_limit response.

calc_ptf_lal1979_group_ii_lower_plastic_limit_from_sand

Estimate lower plastic limit for Group II.

Status: ready-for-implementation

Prediction target: Lower plastic limit

Inputs

Name Type Unit Domain Description
sand number % Sand from 0.02 to 2 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
lower_plastic_limit % Lower plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group II, sand predictor, lower_plastic_limit response.

calc_ptf_lal1979_group_ii_upper_plastic_limit_from_silt

Estimate upper plastic limit for Group II.

Status: ready-for-implementation

Prediction target: Upper plastic limit

Inputs

Name Type Unit Domain Description
silt number % Silt from 0.002 to 0.02 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
upper_plastic_limit % Upper plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group II, silt predictor, upper_plastic_limit response.

calc_ptf_lal1979_group_ii_lower_plastic_limit_from_silt

Estimate lower plastic limit for Group II.

Status: ready-for-implementation

Prediction target: Lower plastic limit

Inputs

Name Type Unit Domain Description
silt number % Silt from 0.002 to 0.02 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
lower_plastic_limit % Lower plastic limit expressed as percentage of oven-dry soil mass.

Note

Table IX, Group II, silt predictor, lower_plastic_limit response.

calc_ptf_lal1979_group_ii_plasticity_index_from_silt

Estimate plasticity index (upper minus lower plastic limit) for Group II.

Status: ready-for-implementation

Prediction target: Plasticity index (upper minus lower plastic limit)

Inputs

Name Type Unit Domain Description
silt number % Silt from 0.002 to 0.02 mm; percentage of the fine earth. Full calibration bounds are not reported.

Outputs

Name Unit Domain Description
plasticity_index % Plasticity index (upper minus lower plastic limit) expressed as percentage of oven-dry soil mass.

Note

Table IX, Group II, silt predictor, plasticity_index response.