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The Effects of Fire Mitigation Methods on Vegetation Species Diversity in Montane Forest – Nederland, CO Kristy Campbell Vegetation Ecology, Summer 2013 CU Mountain Research Center Background • Colorado Wildfires cause property damage, but are necessary for ecosystem restoration and nutrient cycling (Covington et al. 1997). • The need for methods that protect forest biodiversity while protecting human lives and property (USDA Forest Service). The Problem Research Questions • Does fire mitigation affect the number of species (richness) present in an area? • How do fire mitigation methods affect the distribution of vegetative functional groups? Hypothesis – Species richness and functional group distribution may be influenced by fire mitigation methods. • Predictions: • A higher species richness in area of fire mitigation. • An increase in coverage from species of forbs in areas of fire mitigation (Barney and Frischkenecht 1974). Methods • • • • Ponderosa Pine/Douglas Fir/Lodgepole Pine forest (elevation at about 2600m). Most data were collected on either a South facing slope or level ground. 4 nested plots (5m x 5m), each containing 2 Daubenmire plots. Two areas of nested plots • “thinned” • forested (unnaffected). • Random location of plots, but with pseudoreplication Map provided by USDA Forest Service Methods • Each plot was evaluated for species richness and mean percent coverage of three different functional group categories – grasses, forbs, and shrubs (tree coverage could not be measure using Daubenmire plots). • The mean species richness for each 5m x 5m plot was calculated by identifying and counting individual species. • The coverage of species in each Daubenmire plot was recorded and percent coverage of each of these was calculated. • A 2-factor ANOVA was used to evaluate the differences between treatments (thinned and forested) in terms of • species richness • coverage Species Richness Results • Total number of species thinned = 26. • Total number of species forested = 23. • Total number of species found in both the thinned and forested areas = 17. ANOVA RESULTS Figure 1: Number of Species in three Functional groups (Grasses, Forbs, and Shrubs) in two areas of forest (Thinned and unaffected). Error bars are 95% confidence intervals • Error bars overlap, indicating no significant difference in mean number of species in function groups between thinned and forested areas. • P-value of treatment type > 0.05 • No significant difference between thinned and forested areas. Percent Coverage Results (Shrubs absent in all daubenmire plots) ANOVA RESULTS Figure 2: Mean percent coverage of species in two Functional groups (Grasses, Forbs) in two areas of forest (Thinned and unaffected). Error bars are 95% confidence intervals • Error bars overlap, indicating no significant difference in mean percent coverage of species in function groups between thinned and forested areas. • P-value of treatment type > 0.05 • No significant difference between thinned and forested areas. Discussion • Hypothesis – Species richness and functional group distribution may be influenced by fire mitigation methods. • Predictions: • A higher species richness in area of fire mitigation. • An increase in coverage from species of forbs in areas of fire mitigation. • There were slightly more species present in the area of fire mitigation (26 compared to 23). This is a small difference in total species richness. • There were slightly more forbs present in the thinned area (a mean of 9 compared to a mean of 5.5) and forb coverage was slightly greater (mean of 4.75 % compared to a mean of 3%). These differences are not significant, as shown by both the overlapping error bars, as well as the extremely high P values from the ANOVA tests. • My results do not support my hypothesis. Conclusion • Results are inconclusive • Although my results do not support my hypothesis, I cannot conclude that fire mitigation methods do not affect species of vegetation and distribution of functional groups. • Need for greater numbers of samples within the areas I studied. • Need for repetition of the study in other areas of fire mitigation (replication - not pseudoreplication). • Need for repeated follow-up studies of ecological sucession occurring over time (Covington, W. et al. 1997). • Additional research could compare vegetative structure in fire mitigation areas to vegetative structure in areas with fire. Acknowledgments Joseph Graham at the USDA Forest Service emailed me newsletters and maps with information on the West Magnolia project. He also helped explain the difference between Overstory Removal (OST) and thinning as methods of fire mitigation. Literature Cited Barney, M. and Frischknecht, N. 1974. Vegetation Changes Following Fire in the Pinyon-Juniper Type of West-Central Utah. Journal of Range Management. 91-96. Covington, W., Fule, P., Moore, M. Hart, S., Kolb, T., Mast, J., Sackett, S., Wagner, M. 1997. Restoring Ecosystem Health in Ponderosa Pine Forests of the Southwest. Journal of Forestry, Vol 95. No. 4. 23-29. USDA Forest Service. Project Details for Fuels Reduction Project Work in West Magnolia, a High Use Recreation Area Near Nederland, CO. www.fs.usda.gov/arp.