Trees as bioindicators of hillslope degradation by debris flows and dangerous rockfalls along the Lefthand Canyon, Colorado Front Range

作者：Łukasz Pawlik, Brian Buma, Małgorzata Wistuba, Ireneusz Malik, Albert Ślęzak · 发表于：Land Degradation and Development · 年份：2022 · DOI：10.1002/ldr.4575 · 被引用次数：2 · 研究领域：Landslides and related hazards、Fire effects on ecosystems、Tree-ring climate responses

Abstract Trees provide important ecosystem services such as hillslope stabilization from landslides and rockfall protection, and may also be useful indicators of likelihood of those events in the future. Anatomical changes of tree wood are caused by various physical and biological phenomena. There are several geomorphic processes that change tree‐ring characteristics, including hillslope movement, and if detectable, these changes may be used as bioindicators of terrain surface stability. This type of proxy data is vital to places that lack systematic monitoring infrastructure. In the present study, we have evaluated the effects of a heavy rainfall that happened on 11–13 September 2013 in the Colorado Front Range (CFR), which triggered more than 1300 debris flows. We intensely studied one large debris flow that was triggered in the region and the surrounding trees. We explored potential tree‐based records of hillslope instability including compression wood and the method of eccentricity index of tree rings prior to the 2013 event. In addition, the response index was correlated with daily precipitation totals of the previous and current year in a moving window mode. We also evaluated rockfall patterns to explore the frequency and spatial distribution of tree‐scar‐based records. Our primarily goal was to test the method in dry climate conditions and to reconstruct possible soil instability episodes and rockfalls that led to hillslope degradation and tree mortality. In this study...