QI (version 0.1.0)

QIPoly: Quantity-intensity (Q/I) relationship of soil K derived through a second order polynomial i.e., quadratic equation

Description

A quadratic equation of the form "y = ax2 + bx + c" can be fitted to Q/I data to find out different Q/I parameters

Usage

QIPoly(Solution2Soil = Solution2Soil, CKi = CKi, CKf = CKf, CCaMg = CCaMg)

Arguments

Solution2Soil

Ratio of solution volume to soil mass (mL/g or L/kg)

CKi

Initial K concentration (mg/L)

CKf

Final or equilibrium K concentration (mg/L)

CCaMg

Final or equilibrium 'Ca+Mg' concentration (mol/L)

Value

AReK - Equilibrium activity ratio (unitless) Kl - Total labile K (cmolc/kg) PBCK - Potential buffering capacity (cmolc/kg) deltaG0 - The standard free energy of exchange (cal/mol)

References

Wang, J.J., Harrell, D.L., Bell, P.F., 2004. Potassium buffering characteristics of three soils low in exchangeable potassium. Soil Science Society of America Journal 68, 654-661.

Wang, J.J., Scott, A.D., 2001. Effect of experimental relevance on potassium Q/I relationships and its implications for surface and subsurface soils. Communications in Soil Science and Plant Analysis 32, 2561-2575.

Examples

# NOT RUN {
with(data = df, QIPoly(Solution2Soil = Solution_to_Soil_Ratio, CKi = Initial_K,
CKf = Final_K, CCaMg = Final_Ca_and_Mg))
# }