pedotransfer: Pedotransfer functions for soil hydraulic properties

In mrke/NicheMapR: R implementation of Niche Mapper software for biophysical modelling

Pedotransfer functions for soil hydraulic properties

Description

A function to compute soil hydrological properties from information on bulk density and soil composition (clay/silt/sand composition) at particular depths, with capacity to spline results to other depths. Calculations of Campbell's b, air-entry potential and hydraulic conductivity are based on either on equations in Campbell, G. S. 1985. Soil Physics with Basic: Transport Models for Soil-Plant Systems. Elsevier, Amsterdam, or Cosby, B. J., G. M. Hornberger, R. B. Clapp, and T. R. Ginn. 1984. A Statistical Exploration of the Relationships of Soil Moisture Characteristics to the Physical Properties of Soils. Water Resources Research 20:682-690. Field capacity and permanent wilting point are based on Rab, M. A., S. Chandra, P. D. Fisher, N. J. Robinson, M. Kitching, C. D. Aumann, and M. Imhof. 2011. Modelling and prediction of soil water contents at field capacity and permanent wilting point of dryland cropping soils. Soil Research 49:389-407.

Usage

pedotransfer(soilpro, 1, DEP)

Arguments

soilpro	Matrix of n x 5 matrix of soil composition with the following columns 1. depth (cm), 2. bulk density (Mg/m3), 3. clay (%), 4. silt (%), 5. sand (%)
model	Choice of equation to compute soil hydraulic parameters (see details)
DEP	sequence of depths at which results are required, within the range provided by column 1 of input table 'soilpro'

Details

model = 1, choose the pedotransfer function to use; 0 for Cosby et al. (1984) univariate regression (their Table 5), for Cosby et al. (1984) multivariate regression (their Table 4), or 2 for Campbell (1985)

Value

PE air entry water potential (J/kg), Campbell (1985) eq. 5.12, p. 46 or Cosby et al. (1984) Table 5

BB Campbell's b parameter, Campbell (1985) eq. 5.11, p. 45 or Cosby et al. (1984) Table 5

BD bulk density, Mg/m3

KS saturated hydraulic conductivity (kg s / m3), Campbell (1985) eq. 6.12, p. 54 or Cosby et al. (1984) Table 5

FC Field capacity (m3/m3, %) Based on model 6 in Table 6 of Rab, M. A., S. Chandra, P. D. Fisher, N. J. Robinson, M. Kitching, C. D. Aumann, and M. Imhof. 2011. Modelling and prediction of soil water contents at field capacity and permanent wilting point of dryland cropping soils. Soil Research 49:389-407.

PWP Permanent Wilting Point (m3/m3, %) Based on model 2 in Table 7 of Rab et al. 2011 (cited above)

mrke/NicheMapR documentation built on Jan. 13, 2025, 9:11 p.m.