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).