Observed and predicted trends from a sandy loam soil under constant and staggered evaporativity

Abstract

This study was undertaken to check whether the evaporation loss computed from isothermal flow equation supported the previous observations of the authors concerning the sensitivity of evaporation rate in the falling rate stage to evaporativity (E0), with evaporation under higher E0 lagging behind that under a lower E0. Evaporation, computed from the successive moisture profiles predicted numerically from water content gradients and D(è) and K(è) relations, agreed closely with the observed values under the constant, as well as staggered E0 irrespective of redistribution time before commencement of evaporation. Thus, the study has theoretically established that, depending upon the soil and E0¿s involved, cumulative evaporation under lower E0 can exceed that under higher E0. The evaporation rate during the falling rate stage is not only governed by transmission properties of the soil alone but also is influenced by E0.