1141 | 812 | Evaluation of the impact of experimental burnings on soil erosion in forest and scrubland areas (Portugal) | Rocha, José Manuel (a,b); Vieira, António (a); Bento-Gonçalves, António (a)
Forest fires are responsible for the loss of soil vegetation cover and consequent soil erosion. In Portugal this is a period of greatest vulnerability to erosion because of the maximum fire potential in summer (July – September) and the likelihood of intense post-forest fires rainfall the following autumn–winter (November-January)._x000D_
In order to reduce the occurrence of forest fires, the applied methodology aimed at quantifying the effects on the soil of two experimental burnings. While in the area of Plot P (Eucalyptus globulus) the fire was conducted from the flank, in the area of Plot M (scrub) the fire followed the direction of the wind and the slope (upwards). With the application of this type of fire conduction techniques, it was intended to achieve different types of intensity and time of exposure of the soil to fire._x000D_
With the implementation of experimental burnings in forest of the Eucalyptus globulus and in scrub areas, an attempt was also made to evaluate the losses and soil modifications verified after the fire. In the study area, two erosion plots (modified Gerlach method) were installed to assess the erosion verified in the soil. _x000D_
The erosion increased especially in the first 6 months after the used experimental burnings, related to the occurrence of significant precipitation episodes. The transport of sediments in plot M was higher due to the lack of vegetation cover. Sediment production increased in the first 4 months by decreasing organic matter to aggregate soil elements. In plot P the existence of trees prevented the erosive action of precipitation._x000D_
In conclusion, it is clear that fire can have a significant impact on soils with important consequences for water retention capacity, infiltration, and erosion processes. In order to mitigate these impacts, it is necessary to carry out appropriate management practices for each type of area to reduce the risk of fire and increase forest resilience._x000D_
Rocha, José Manuel (a,b); Vieira, António (a); Bento-Gonçalves, António (a)
(a) CECS, Dep. of Geography, University of Minho, Portugal; (b) GRAM, University of Barcelona, Spain
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