The influence of soil moisture on the spatial and temporal variability of soil electrical conductivity

Soil electrical conductivity (EC) is a soil quality indicator that is associated to attributes of interest for site-specific soil management such as soil moisture and texture. The present study performed spatial monitoring of soil moisture in two experimental fields of Brazilian soils for two consecutive years and modeled its influence on soil EC. Soil EC, moisture and clay content were evaluated by statistical, geostatistical and regression analyses. Semivariogram models, adjusted for soil moisture, had strong spatial dependence, but the relationship between soil moisture and soil EC was obtained only in one of the experimental fields, where soil moisture and clay content range was higher. In this same field, the correlation coefficients between soil moisture and clay content were above 90%. In the second field, the low soil moisture and clay content range explain the absence of a relationship between soil electrical conductivity and soil moisture.