Soil properties related to the dynamics of ammonia volatilization from urea applied to the surface of acidic soils

Abstract

Ammonia volatilization after urea application is the most likely mechanism responsible for variation in urea performance even on acidic soils. The rate and the cumulative amount of NH3 loss are important features for any soil. Field rates of NH3 volatilization were simulated by using ventilated enclosures in the laboratory. The daily rates of NH3 volatilization from 36 soils of widely differing properties from Northern Ireland were measured for 14 days. Cumulative loss rates for each soil were fitted to a logistic model from which the total cumulative loss (Amax) and the time for maximum rate of volatilization (Tmax) were calculated. Stepwise multiple linear regression analysis was used to relate Amax and Tmax to soil properties.