A simple method to assess the susceptibility of soils to form surface seals under field conditions

Abstract

A simple method to assess sealing susceptibility under natural field conditions was developed and tested. The principal of the method consists in taking samples of sealed soil and unsealed reference samples with standard 100 cm 3 sampling cylinders following major rainfall events during the vegetation period. Saturated hydraulic conductivity is then determined in the laboratory with a permeameter. Results showed that the sealing dynamics of soils under field conditions as a function of rainfall energy can be easily quantified with the proposed method. Calculation of relative conductivities of sealed samples with respect to unsealed reference samples, also termed sealing index, is proposed as a means of making sites comparable. The slope of the regression of relative conductivity as a function of rainfall energy is introduced as a measure of sealing susceptibility. The latter seems to correlate with soil properties such as aggregate stability.