Soil moisture levels and their relation to water potentials of cotton leaves

Abstract

Simultaneous measurements of volumetric water content (θ) in the soil profile by neutron scattering (NP), time domain refiectometry (TDR), and tensiometers (TENS), and leaf water potential (LWP) were carried out in a commercial cotton field under semi-arid conditions. The good correlation between averaged θ values by TENS and TDR suggests that the preferred TDR technique can replace the more commonly used TENS. Slopes of the linear relations between LWP and θ increase in the order NP<TDR<TENS This order may be explained by the combination of the ‘sphere-of-influence’ soil volume and the specific property of the water molecules sensed by the particular measuring technique.