Immediate effects of prescribed burning, chopping and clearing on runoff, infiltration and erosion in a shrubland area in Galicia (NW Spain)

Abstract

The immediate effects of three different fuel management treatments on runoff, infiltration and erosion were evaluated in a mixed heathland in Galicia (NW Spain). The treatments compared were: prescribed burning, shrub chopping and shrub clearing.Rainfall simulations were conducted immediately before and after fuel reduction treatments. A rainfall rate of 67 mm h À1 was applied for 30 min to each runoff plot.Application of treatments significantly affected runoff and infiltration, but the parameter most affected by treatment was soil erosion, especially after prescribed burning. However, sediment yields measured immediately after treatments were low in all the cases, varying from 32 kg ha À1 after shrub clearing to 248 kg ha À1 after prescribed burning. In the rainfall simulation plots subjected to prescribed burning, the maximum temperatures reached at mineral soil surface during burns significantly affected soil losses. The organic layer remaining after treatments and soil moisture contents appeared to be critical variables in controlling runoff and erosion during the first rainfall event following fuel reduction treatments. When the remaining organic layer was removed just after treatments and a new rainfall simulation was carried out, mean infiltration rate trended to decrease and cumulative runoff and sediment yield tended to increase.The above information could be useful for determining whether fuel management prescriptions are compatible with fire hazard reduction and soil conservation.

Post-fire evolution of soil properties and vegetation cover in a Mediterranean heathland after experimental burning: A 3-year study

“…The average fuel load in the area was 2.7 ± 0.5 kg m −2 . Fuel loads determined in heathlands ranged between 1.8 kg m −2 (SW Spain, Zavala et al, 2009) and 2.0 kg m −2 (in Galicia, NW Spain; Fernández et al, 2008). Small variations were observed in the severity and intensity of fire across the burnt area.…”

Does soil burn severity affect the post-fire runoff and interrill erosion response? A review based on meta-analysis of field rainfall simulation data

“…3). In three of these cases (Fernández et al, 2006(Fernández et al, , 2008(Fernández et al, , 2012, the authors of the publications provided this information, upon a specific request. In the remaining four cases (Dobrowolsky et al, 1992;Emmerich-Cox, 1994;Johansen et al, 2001b;Knight et al, 1983), the present authors felt confident to estimate soil burn severity following the classification by Vega et al (2013a), based on the description of the fire and of post-fire conditions in the article.…”

“…Field rainfall simulations experiments (RSE's) have been widely used to study the effects of fire on runoff and sediment losses (e.g., Emmerich and Cox, 1992;Robichaud, 2000;De Luis et al, 2003;Ferreira et al, 2005;Fernández et al, 2008;Groen and Woods, 2008). Nevertheless, the most comprehensive recent reviews on post-fire erosion Shakesby, 2011;Moody et al, 2013) have not included these RSE studies.…”

Chaparral shrub recovery after fuel reduction: a comparison of prescribed fire and mastication techniques

“…Drastic mortality rates in the early recovery years can be caused by a combination of factors, including competition, herbivory, and the insufficient root development to handle summer drought conditions. Seed bank loss can largely be attributed to erosion (Keeley 1977) and coincidence of bare soil and heavy rain may increase erosion (Fernández et al 2008;Gill and Groves 1981). Fernandez et al (2008) reported that fuel treatments affected the initial runoff, infiltration, and erosion in a gorse shrubland community in northwest Spain, especially after prescribed burning compared to mastication.…”