OBIC (version 4.2.3)

calc_waterretention: Calculate indicators for water retention in topsoil

Description

This function calculates different kind of Water Retention Indices given the continuous pedotransferfunctions of Wosten et al. (2001) These include : 'wilting point','field capacity','water holding capacity','plant available water' and 'Ksat'

Usage

calc_waterretention(
  A_CLAY_MI,
  A_SAND_MI,
  A_SILT_MI,
  A_SOM_LOI,
  type = "plant available water",
  ptf = "Wosten1999"
)

Value

The function returns by default the amount of plant available water in the ploughing layer of the soil (in mm). A numeric value. If another type of output is selected, the function gives also the amount of water at 'wilting point' or 'field capacity' or 'water holding capacity'. Also the saturated permeability 'Ksat' can be selected. Units are always in mm, except for Water Holding Capacity (

Arguments

A_CLAY_MI

(numeric) The clay content of the soil (%)

A_SAND_MI

(numeric) The sand content of the soil (%)

A_SILT_MI

(numeric) The silt content of the soil (%)

A_SOM_LOI

(numeric) The organic matter content of the soil (%)

type

(character) The type of water retention index. Options include c('wilting point','field capacity','water holding capacity','plant available water','Ksat')

ptf

(character) Pedotransfer functions to calculate van Genuchten parameters. Options include c('Wosten1999', 'Wosten2001', 'Klasse')

References

Wosten et al. (2001) Pedotransfer functions: bridging the gap between available basic soil data and missing hydraulic characteristics. Journal of Hydrology 251, p123.

Examples

calc_waterretention(A_CLAY_MI = 20.5,A_SAND_MI = 65,A_SILT_MI = 14.5,A_SOM_LOI = 3.5)
calc_waterretention(A_CLAY_MI = 5,A_SAND_MI = 15,A_SILT_MI = 80,A_SOM_LOI = 6.5)
calc_waterretention(A_CLAY_MI = 5,A_SAND_MI = 15,A_SILT_MI = 80,A_SOM_LOI = 6.5, 
type = 'water holding capacity')