(Elsevier, 2012) Giménez Díaz, Rafael; Casalí Sarasíbar, Javier; Grande Esteban, Ildefonso; Díez Beregaña, Javier; Campo-Bescós, Miguel; Álvarez-Mozos, Jesús; Goñi Garatea, Mikel; Proyectos e Ingeniería Rural; Landa Ingeniaritza eta Proiektuak; Gestión de Empresas; Enpresen Kudeaketa; Gobierno de Navarra / Nafarroako Gobernua
It is recognised that the hydrological and erosion processes in watersheds are very much conditioned by
the (inter)action of a number of variables. This paper covers a 15-year period of studying those factors
that have a major influence on the sediment yield and transport during individual hydrological events in
a small Mediterranean agricultural watershed. Multivariate statistical techniques such as cluster analysis
and principal component analysis were applied for the interpretation of datasets. In addition, the relationships
between suspended sediment concentration and discharge (hysteretic loops) were also analysed.
The hydrological response of the studied watershed is mainly controlled by the antecedent condition of
the flow. Most of the runoff and sediment are generated during the wet season when vegetation cover
is scant and saturation overland flow occurs promptly as a response to almost any rainfall events. In
contrast, during the dry seasons even if high-intensity rainfalls normally occur, very scant runoffs are,
however recorded, at the exit of the watershed. Most of the eroded sediment seems to come from riparian
areas. The discharge registered at the watershed outlet up to 1 h prior to the flood is a very good surrogate
for antecedent soil moisture.
