Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → Pays-Bas → 2002 → Landscape sensivity to erosion in three semi-arid Central Andean geo-ecosystems

Universiteit van Amsterdam (2002)

Landscape sensivity to erosion in three semi-arid Central Andean geo-ecosystems

Coppus Ruben

Titre : Landscape sensivity to erosion in three semi-arid Central Andean geo-ecosystems

Auteur : Ruben Coppus

Université de soutenance : Universiteit van Amsterdam

Grade : Doctor 2002

Résumé
Thee interactions between erosion processes and soil and vegetation were studied in three different geo-ecosystems in the southern Bolivian Andes. The principle objective of this study was to identify and characterise physiographical units in the landscape that are sensitive to erosion.. To accomplish this, soil and vegetation properties were studied in order to localize and characterize what are termed Erosion Sensitive Areas (ESA). This helped provide insight into the relative importance of grazing as opposed to geology and climate in explaining the current extent of active erosion features. Inn the areas that are most sensitive for erosion, the biomass of palatable species, organic matter content and available water are low and grazing density is low or moderate. The areas with high grazing density have a high biomass of palatable species and the organic matter content and available water are high. The distribution of the ESAs coincides with a semi-arid climate,, low biomass of short grasses and highly erodible parent material. Current putative reductions in grazing intensity do not seem to have resulted in less erosion.. This suggests that past grazing history has altered the sensitivity to erosion, and the resilience of certain areas, to such an extent that erosion rates are high despite current low grazing intensity. This also suggests that contemporary degradation processes are not driven by current grazing densities but by climatic and geomorphological factors.

Version intégrale

Page publiée le 4 avril 2008, mise à jour le 2 juin 2022