Effect of surface roughness on runoff and erosion in a mediterranean ecosystem: the role of fire

Mechanisms at the micro (patch) scale influencing runoff and erosion processes following a forest fire were investigated. The study was conducted in a Mediterranean mountainous region with a mean annual rainfall of 690 mm, Terra Rossa soil, and vegetation composed of a dense shrubland of Pinus halepensis and Quercus calliprinos. Simulated rainfall experiments were carried out on plots representing different intervals of time elapsed since a fire; i.e., immediately after fire, two weeks after fire, one year after fire. Unburned plots were also used for comparison. At a local scale, great variability was found whereby some patches produced high runoff and sediment yields following fire, while others did not. The conclusion is that the main effect of fires of low to moderate intensity is to produce a mosaic-like surface containing both rough patches in which there is almost no chance for runoff generation, and relatively smooth patches in which fire can subsequently lead to higher runoff and erosion rates.

[1]  P. Kutiel,et al.  Soil properties beneath Pinus halepensis and Quercus calliprinos trees on burned and unburned mixed forest on Mt. Carmel, Israel , 1987 .

[2]  Y. Benyamini,et al.  Rainfall infiltration into bare soils , 1977 .

[3]  J. G. Goldammer,et al.  Fire in ecosystem dynamics: Mediterranean and northern perspectives. , 1990 .

[4]  P. Kutiel,et al.  Fire impacts on soil nutrients and soil erosion in a Mediterranean pine forest plantation , 1993 .

[5]  H. Mücher,et al.  A consistency index and rainwash mechanisms on Belgian loamy soils , 1981 .

[6]  A. J. Low.  THE STUDY OF SOIL STRUCTURE IN THE FIELD AND THE LABORATORY , 1954 .

[7]  Santiago de Compostela.  EVALUATION OF THE U.S.L.E. FOR THE PREDICTION OF EROSION IN BURNT FOREST AREAS IN GALICIA (N.W. SPAIN) F. Diaz-Fierros V., E. Benito Rueda and R. Perez Moreira, , 1987 .

[8]  V. H. Scott,et al.  EFFECTS OF HEAT AND BRUSH BURNING ON THE PHYSICAL PROPERTIES OF CERTAIN UPLAND SOILS THAT INFLUENCE INFILTRATION , 1956 .

[9]  A. C. Imeson,et al.  The effects of fire and water repellency on infiltration and runoff under Mediterranean type forest , 1992 .

[10]  Rorke B. Bryan,et al.  Laboratory experiments on the variation of soil erosion under simulated rainfall , 1981 .

[11]  P. Kutiel.  Fire and ecosystem heterogeneity: A mediterranean case study , 1994 .

[12]  A. Imeson,et al.  Assessing soil aggregate stability by water-drop impact and ultrasonic dispersion , 1984 .

[13]  R. Moreira,et al.  Evaluation of the U.S.L.E. for the prediction of erosion in burnt forest areas in Galicia (N.W. Spain) , 1987 .

[14]  Y. Avnimelech,et al.  Potentiometric Determination of Soil Organic Matter , 1972 .

[15]  Y. Benyamini,et al.  The effect of fire-induced surface heterogeneity on rainfall-runoff-erosion relationships in an eastern Mediterranean ecosystem, Israel , 1995 .