Tesis doctoral de Gemma Dunjo Denti
The aim of this research was to develop a simple methodology for precisely appraising the status and trends of desertification in a semi-arid mediterranean catchment, through a so-called desertification indicator system (dis). the assessment of land degradation processes at plot scale was conducted through the monitoring of runoff-erosion microplots. As a result, a set of variables such as soil erosion, soil organic matter and vegetation cover, were identified as the most important factors for soil quality in the target area, and some of these were applied as inputs in the dis model, accounting for their relevance not only at the plot but also at catchment scale. regarding the parameter sensitivity of the dis model, the saturated hydraulic conductivity as well as the erodability factor were identified as the most sensitive variables, whereas the soil-b parameter and also the vegetation cover and the slope angle were revealed as those affecting soil erosion and overland flow the least. Likewise, the model showed greater sensitivity to the dry than to the normal or wet rainfall scenarios. from the results of a plot scale model validation exercise it may be concluded that the behaviour of runoff and erosion at plot scale is somewhat different to that at the landscape scale: a scaling problem. At the plot scale, soil erosion was greatly overestimated by the model in the least vegetated environments and especially under cultivated olive trees, whilst it was slightly underestimated in the most vegetated ones (e.G. Dense cork trees). The same pattern was found for overland flow, although measured and modelled runoff data were in the same order of magnitude and so errors were smaller than for erosion. nevertheless, results may be considered significant in terms of which land uses are the most and least potentially degraded and in this way, the model fulfils its objective as a desertification support tool as it identifies the patterns of cha
Datos académicos de la tesis doctoral «Developing a desertification indicator system for a small mediterranean catchment a case study from the serra de rodes, alt emporda, catalunya, spain«
- Título de la tesis: Developing a desertification indicator system for a small mediterranean catchment a case study from the serra de rodes, alt emporda, catalunya, spain
- Autor: Gemma Dunjo Denti
- Universidad: Girona
- Fecha de lectura de la tesis: 23/03/2004
Dirección y tribunal
- Director de la tesis
- Giovanni Pardini
- Tribunal
- Presidente del tribunal: Garcia ruiz José María
- francesc Gallart gallego (vocal)
- john Wainwright (vocal)
- mark Mulligan (vocal)