16A.28
FF,N - Using RX fire to maintain shaded fuelbreak areas in Southern Spain
Francisco Senra-Rivero, Colorado State University, Fort Collins, CO
The use of RX-fire is limited in Southern Spain. This is especially due to the characteristics of the vegetation in these Mediterranean areas. However, the use of RX-fire could be an interesting alternative for the maintenance of shaded fuelbreak areas.
These areas are characterized by the existence of previous treatments (breaking the vertical continuity as well as reducing the understory fuel load), relatively high amount of fine fuels (from previous treatment and superior canopy) and are safer against pyre-escapes because of the proximity to roads. From the economical point of view, the existence of trees within the area of treatment limit some mechanical treatments. This imply the use of “manual” ones, more expensive, making the prescribed burn a cost-efficient alternative.
With the aim of studying the viability of such fuel treatment, eight shaded fuelbreak areas were burned in Malaga province (Andalusia State, Spain), during 1999 and 2000 years. All of them were Pinus pinaster stands, but with different understory structures and species, and using different firing techniques. The objectives were specially focused in comparing fuel consumption and availability among the plots and defining the minimum base crown height to secure the survival of the trees as well as maintain the burn under prescription.
With relevance to the fuel consumption and availability, the relations to be tested are: the fuel consumption among the units; to compare the fuel consumption among the same timelag particles for those units with the same severity pattern; and finally, to determine the relationship between fuel consumption vs. the under-story vegetation complex as well as the fire and meteorological conditions during the burn.
The second objective is based in testing the correlations between the observed crown severity patterns and both the fire behavior and vegetation complex pre-burn conditions, as well as the tree mortality observed. Thus, the correlation among scorch height and base crown height or understory fuel load will be of interest. The result will be correlated to a cost analysis, so in case a pruning is needed we will know the budget necessary for this treatment and we can compare it with other silvicultural treatments in order to determine the viability of the prescribed burning.
The anticipated result is that shaded fuelbreak areas ease the use of prescribed fire, mainly because of the existence of fine fuels from the superior canopy as well as a vertical discontinuity due to the previous silvicultural treatments. The economic analysis showed the convenience of broad-cast burning, instead of other treatment, for those units bigger than 1.5 has in all cases. This is especially important as the investment realized in maintaining these fuelbreak areas yearly is more than half of the overall budget within the fire prevention actions in the State. Thus the use of RX-fire to maintain these areas should be developed.
Session 16A, Other
Wednesday, 9 October 2002, 1:30 PM-1:30 AM
Previous paper Next paper