ME_PHharm {soilassessment}

Mixed-effects model for harmonizing soil pH (KCl or CaCl2) to the equivalent pH (water)

Description

A function for harmonizing soil pH (KCl or CaCl2) to the equivalent pH (water) using mixed effects approach

Usage

ME_PHharm(ph, TEXCLASS, model, phtype)

Arguments

ph

a vector or single value of soil ph in KCl or CaCl2 to be harmonized

TEXCLASS

soil textural class of the soil whose ph is to be harmonized. String or test entry of USDA textural classes: Cl, ClLo, Lo,LoSa,Sa,SaCl,SaClLo,SaLo,SiCl,SiClLo,SiLo,Si,CS,MS,HCL,FS. The classes can be determined from Clay, Silt, and Sand proportions using createTexturedata function

model

functional model for relating ph in KCl or CaCl to be harmonized and equivalent ph (water). Models considered are second order polynomial, sigmoid, spherical, gaussian, exponential, power, and linear functions. The default is polynomial

phtype

KCl or CaCl2 solution for ph. The default is CaCl2

Details

ph harmonization models, which were developed using global datasets, are designed to standardize soil ph for applications in soil salt classification

Value

numeric value of equivalent ph (water)

Note

The function only works with USDA soil textural classes. Convert other soil textural classes to USDA classes for all applications with this function.

Author(s)

Christian Thine Omuto

See Also

ME_ECharm, ECconversion1, ECconversion2

Examples

newdata=data.frame(ph=c(1.6,8.3,5.7,12.1,2.2),tex=c("Cl","SaCl","LoSa", "Si","SaClLo"))
newdata$pH2=ME_PHharm(newdata$ph,newdata$tex,"exponential","kcl")