Title:
SOILS WATER EROSION – FACTOR OF PHYSIC AND HUMAN DESERTIFICATION
Author:
António Canatário Duarte (acduarte@ipcb.pt), Victor Pissarra Cavaleiro (cavaleiro@ubi.pt) e Ana Paula Leite (anappleite@hotmail.com)
Publication:
Revista Egitania Sciencia - Volume 11
Abstract:
Water erosion, with the consequent soil loss, represents a cost to
agriculture as it means loss of productive land, nutrients and organic matter as well as environmental degradation of water resources downstream. This cycle
of unsustainability will lead to a physical desertification of places accompanied
by a human desertification. It is essential the understanding of the process, the
influence of each factor that it depends on, for the adoption of more effective
actions for its prevention. This study takes place in a small hydrographic basin
(190 ha), located in the Idanha-a-Nova county, where a suitable experimental
device was installed. The randomness of the Mediterranean climate can
determine years with higher volumes of precipitation that correspond to more
erosive events, and driest years with the occurrence of fewer erosive events,
but with expanded erosive potential in some of them. In this analysis we draw
conclusions about the strong protective effect of vegetation by comparing the
sediment concentration in water in two erosion events, corresponding to quite
different covering conditions in the basin. The superficial leakage will be more
or less powered, depending on how other factors that influence the erosive
process, namely, vegetation, soil, topography, and agricultural practices of
farmers will manifest themselves.
Keywords:
Water erosion, soils, physical desertification, human desertification, mediterranean
climate
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