Short-term Experimental Fire Effects in Soil and Water Losses in Southern of Spain

This study deals with the experimental fire effects in overland flow and soil erosion at plot scale and considering rainfall erosivity. The study was conducted in from May 2011 to Dec 2013. Six plots of 12-m length and 2-m width are considered: four of them were burned, whilst two of them remained in natural conditions. Overland flow was collected in deposits of 250 L after each rainfall event, measured at a meteorological station. Larger rainfall intensities and erosivity were registered after summer and, thus, overland flow and sediment yield, but one order of magnitude higher in the burned plots than in the unburned ones. Especially, the difference in overland flow and soil loss between both set of plots were nearly three folds larger whether the rainfall intensity exceeded 30 mm h⁻¹ during 15-min intensity. It is remarkable that the most erosive event generating the maximum values of overland flow and soil loss was registered 16 months after the experimental fire when a rainfall event of 99·2 mm h⁻¹ occurred. This delay is considered as consequence of soil surface conditions and ash cover.