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Postfire rehabilitation treatments: are we learning what works?
Robichaud, P.R.; Brown, R.E. 2005.
Postfire rehabilitation treatments: are we learning what works?
In Moglen, G.E., ed.,
Managing Watersheds for Human and Natural Impacts: Engineering, Ecological, and Economic Challenges.
Proceedings of the 2005 Watershed Management Conference, July 19-22, 2005, Williamsburg, VA;
Sponsored by Environmental and Water Resources Institute (EWRI) of the American Society of Civil Engineers.
12 p.
Keywords: rehabilitation
Links:
PDF [274 KB]
Available to purchase: By subscription from ASCE
Abstract:
Major concerns after wildfires are the increased erosion and flooding potential
due to loss of the protective forest floor layer, loss of water storage, and the creation
of water repellent soil conditions. Treatments to mitigate postfire erosion and runoff
are commonly applied on highly erodible areas; however the effectiveness of these
treatments has had limited scientific evaluation. In recent years postfire hillslope
treatment effectiveness has been evaluated by using sediment fences and small
catchments to directly measure sediment yields from burned hillslopes and relate
those results to the specific rain events that caused them. In addition, the erosion from
areas treated with various rehabilitation treatments (seeding, mulching, erosion
barriers, etc.) is compared to non-treated areas. Although many of these studies are
still in progress, preliminary results suggest that some mitigation treatments may help
reduce erosion for some, but not all, rain events. Immediately after installation,
contour-felled log erosion barriers can reduce erosion up to 70% for small rain
events. For high intensity rain events (10-min max intensity of 40 mm hr-1 or greater)
there little difference in erosion reduction between treated and non-treated areas.
Other studies suggest that the natural mulch provided by dead conifer needles in areas
of low and moderate burn severity can reduce rill erosion by 30 to 40% and interrill
erosion by 50 to 70%.
Moscow FSL publication no. 2005e
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