TEMPERATURE DEPENDENCE OF NITROGEN MINERALIZATION RATE CONSTANT - A THEORETICAL APPROACH

摘要

Experimental evidence suggests that nitrogen (N) mineralization proceeds differently under fluctuating temperature conditions than it does at constant temperature. Although N mineralization is believed to follow first-order kinetics, and the mineralization rate constant is believed to follow Q(10) temperature dependence, no effort has been made to use this information to predict the effect of fluctuating temperature on N mineralization. In this paper, we present solutions to the first-order N mineralization equation for a rate coefficient with Q(10) temperature dependence. Solutions are presented for a number of simple patterns of temperature fluctuation in time. Example calculations show that the nonlinear temperature dependence of the Q(10) relationship causes mineralization under fluctuating temperature conditions to exceed that occurring at constant temperature. Sensitivity analysis shows that the Q(10) constant and the amplitude of the temperature fluctuation strongly influence the difference in mineralization obtained for the two temperature patterns. These results can be used to improve the design of experiments conducted to study the effect of temperature fluctuations.