RZWQM2-Phosphorus Model is capable of simulating the fate and transport of phosphorus in the soil-plant system at a point scale. It is featured with the process of describing dissolved and particulate phosphorus loss in both surface runoff and subsurface drainage flow, as well as plant P uptake, as affected by manure application, macropore flow and agronomic management practices. The state-of-the-art phosphorus module was developed based on most recent findings such as advanced dynamic adsorption, manure P partition, colloidal particle transport, macropore flow, and linear groundwater P reservoir.

The P module is incorporated in Root Zone Water Quality Model (RZWQM2) to take advantage of its hydrological and biological subroutines. Infiltration and runoff is simulated using Green-Ampt equation, and soil water is re-distributed following the Richard’s equation. Subsurface drainage is computed using the steady-state Hooghoudt’s equation, and the macropore flow is governed by the Poiseuille’s Law. Carbon-nitrogen cycle is driven by microbial biomass and the environmental factors. DSSAT 4.0 (Decision Support System for Agrotechnology Transfer) and SHAW (Simultaneous Heat and Water model) are linked to RZWQM2 to simulate crop growth and freeze-thaw cycles, respectively.

This project is sponsored by NSERC-Discovery (2014-2019)

RZWQM2-Phosphorus executable setup file (First released on May 01, 2018; Last updated on Dec 17 2023) RZWQM2Install-2023-12-17.msi

RZWQM2-Phosphorus Techincal Report: RZWQM2-P.pdf

Pan, P, Z. Qi, A. Koehn, A. Leytem, D. Bjorneberg, L. Ma. 2023. Modification of RZWQM2-P model to simulate soil labile and total phosphorus in an irrigated and manure amended cropland. Computers and Electronics in Agriculture 206, 107672

Pan, P., Z Qi, T.Q Zhang, L. Ma. 2023. Modeling phosphorus losses to subsurface drainage under tillage and compost management. Soil & Tillage Research 277, 105587.

Debasis Sadhukhan, Zhiming Qi, T.Q. Zhang, Chin Tan, Liwang Ma, Allan Andales. 2019. Development and evaluation of a phosphorus (P) module in RZWQM2 for phosphorus management in agricultural fields Environmental Modelling & Software 113, 48-58

D Sadhukhan, Z Qi, TQ Zhang, CS Tan, L Ma. 2019. Modeling and Mitigating Phosphorus Losses from a Tile-Drained and Manured Field Using RZWQM2-P Journal of environmental quality 48 (4), 995-1005

Qi, H., Z. Qi, T.Q. Zhang, C.S. Tan, and D. Sadhukhan. 2018. Modeling phosphorus losses through surface runoff and subsurface drainage using ICECREAM. Journal of Environmental Quality. 47:203-211.

D Sadhukhan, Z Qi, Y Li, T Zhang, CS Tan, L Ma. 2020. Global sensitivity analysis of RZWQM2-P in simulation of agricultural phosphorus loss 2020 ASABE Annual International Virtual Meeting