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HUMAN SUPPRESSION OF SNOW AVALANCHES AND VEGETATION DYNAMICS IN THE SUBALPINE ECOSYSTEM. by Nick Ludolph Winter Ecology – Spring 2010. Mountain Research Station, University of Colorado, Boulder. Introduction. Initial Research Idea – Repeat Photography Why it did not work
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HUMAN SUPPRESSION OF SNOW AVALANCHES AND VEGETATION DYNAMICS IN THE SUBALPINE ECOSYSTEM by Nick Ludolph Winter Ecology – Spring 2010 Mountain Research Station, University of Colorado, Boulder
Introduction • Initial Research Idea – Repeat Photography • Why it did not work • My Next Idea – Transects • Avalanche Danger Too Extreme • Broader Picture – disturbance effects summer vegetation dynamics too • Literature Review – Human suppression and vegetation
Introduction (cont.) • Question: What is the effect of human suppression of the avalanche disturbance on the vegetation dynamics of subalpine forests? • Hypothesis: Suppression of avalanches will decrease the biodiversity and ecosystem health found in avalanche areas • Alternate Hypothesis: Suppression will not decrease biodiversity or ecosystem health
Introduction (cont.): Importance • Lack of research in general(Bebi et al 2008) • Effect on forest structure(Kulakowski et al 2006) • Regular disturbance (Rixen et al 2007) • Affects other forest disturbances(Veblen et al 1994) • Economics – is suppression necessary?
Avalanche Suppression Image: http://deputy-dog.com/2008/03/man-vs-mountain-avalanche-control.html
THE AFFECT OF SNOW FENCES (Fuchs et al 2006)
THE EFFECTS ON VEGETATION OF ALTERING AVALANCHE FREQUENCY • Diversity • Structure of Individuals • Small DBH • Shorter • Slower growth rates • Structure of Stands • Homogenous • Frequency (Bebi et al 2009)
Areas for Further Study • Land use change • Climate change • Increases avalanche frequency (Huggel 2008) • Longer term effects • Other Suppression techniques Image: http://www.les-angles.com/hiver/images/stories/securite3.jpg
Literature Cited Bebi, P., Kulakowski, D., & Rixen, C. (2009). Snow avalanche disturbances in forest ecosystems‚ÄîState of research and implications for management. Forest Ecology and Management, 257, 1883-1892. Retrieved February 17, 2010, from the Web of Science database. Fuchs, S., Thoni, M., McAlpin, M. C., Gruber, U., & Brundl, M. (2006). Avalanche hazard mitigation strategies assessed by cost effectiveness analyses and cost benefit analyses—evidence from Davos, Switzerland. Natural Hazards, 41, 113-129. Retrieved February 25, 2010, from the SpringerLink database. Huggel, C., Caplan-Auerbach, J. and Wessels, R. (2008): Recent extreme avalanches: triggered by climate change? EOS, Transactions, American Geophysical Union, 89(47), 469-470. Ives, J. D., Mears A. I., Carrara P. E., and Bovis M. J. (1976). Natural Hazards of Mountain Colorado. Annals of the Association of American Geographers, 66, 129-144. Retrieved February 25, 2010, from the Web of Science database. Kittel, T. (Director) (2010, February 7). Winter Vegetation Ecology. Winter Field Ecology. Lecture conducted from University of Colorado, Niwot Ridge. Kulakowski, D., Rixen, C., & Bebi, P. (2006). Changes in forest structure and in the relative importance of climatic stress as a result of suppression of avalanche disturbances. Forest Ecology and Management, 223, 66-74. Retrieved February 16, 2010, from the Web of Science database. Man vs mountain: avalanche control structures. (2008 February 3). Deputy Dog. Retrieved February 26, 2010, from http://deputy-dog.com/2008/03/man-vs-mountain-avalanche-control.html Rixen, C., Haag, S., Kulakowski, D., & Bebi, P. (2007). Natural avalanche disturbance shapes plant diversity and species composition in subalpine forest belt. Journal of Vegetation Science, 18, 735-742. Retrieved February 17, 2010, from the Web of Science database. Veblen, T. T., Hadley, K. S., Nel, E. M., Kitzberger, T., Reid, M., & Villalba, R. (1994). Disturbance regime and disturbance interactions in a Rocky Mountain Subalpine Forest. Journal of Ecology, 82, 125-135. Retrieved February 16, 2010, from the Web of Science database.