Spatio-temporal interactions
A set of spatio-temporal interactions was considered from variations between events related to the rainfall intensity that were associated with singular conditions of the evaluated spatial heterogeneity. In soil solution, we observed situations where the DOC adsorption rates to the soil decrease when the rainfall intensity increases, such behavior spatially is limited to areas where there is a large amount of OM incorporated in the soil: the top of the soil (0-50 cm) in the summit; and in-depth (50-100 cm) in the bottom valley (OM buried by colluvial dynamics).
As intense manifestations of this behavior, in these compartments and at times of higher rainfall intensities, the DOC concentration increased in depth indicating the change of soil behavior from an adsorption compartment to a desorption compartment (DOC source compartment) for the transport by water. This should be due to increased water elution capacity for OM desorption by increased soil pore pressure under stormy conditions (Stone and O’Shaughnessy, 2005).