气候变化领域集成服务门户(CCPortal): Particle motion on burned and vegetated hillslopes

CCPortal

DOI	10.1073/pnas.1922495117
	Particle motion on burned and vegetated hillslopes
	Roth D.L.; Doane T.H.; Roering J.J.; Furbish D.J.; Zettler-Mann A.
发表日期	2020
ISSN	0027-8424
起始页码	25335
结束页码	25343
卷号	117 期号:41
英文摘要	Climate change is causing increasingly widespread, frequent, and intense wildfires across the western United States. Many geomorphic effects of wildfire are relatively well studied, yet sediment transport models remain unable to account for the rapid transport of sediment released from behind incinerated vegetation, which can fuel catastrophic debris flows. This oversight reflects the fundamental inability of local, continuum-based models to capture the long-distance particle motions characteristic of steeplands. Probabilistic, particle-based nonlocal models may address this deficiency, but empirical data are needed to constrain their representation of particle motion in real landscapes. Here we present data from field experiments validating a generalized Lomax model for particle travel distance distributions. The model parameters provide a physically intuitive mathematical framework for describing the transition from light- to heavy-tailed distributions along a continuum of behavior as particle size increases and slopes get steeper and/or smoother. We show that burned slopes are measurably smoother than vegetated slopes, leading to 1) lower rates of experimental particle disentrainment and 2) runaway motion that produces the heavy-tailed travel distances often associated with nonlocal transport. Our results reveal that surface roughness is a key control on steepland sediment transport, particularly after wildfire when smoother surfaces may result in the preferential delivery of coarse material to channel networks that initiate debris flows. By providing a first-order framework relating the statistics of particle motion to measurable surface characteristics, the Lomax model both advances the development of nonlocal sediment transport theory and reveals insights on hillslope transport mechanics. © 2020 National Academy of Sciences. All rights reserved.
英文关键词	Dry ravel; Nonlocal transport; Postfire erosion; Roughness; Sediment transport
语种	英语
scopus关键词	Article; biomechanics; controlled study; mathematical model; particle size; photogrammetry; physical parameters; priority journal; probability; sediment; sediment transport; stochastic model; validation process; vegetation; forest; motion; particle size; plant; soil; theoretical model; wildfire; Forests; Models, Theoretical; Motion; Particle Size; Plants; Soil; Wildfires
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160768
作者单位	Roth, D.L., Department of Geology and Geological Engineering, Colorado School of Mines, Golden, CO 80401, United States; Doane, T.H., Department of Earth and Atmospheric Sciences, Indiana University, Bloomington, IN 47405, United States; Roering, J.J., Department of Earth Sciences, University of Oregon, Eugene, OR 97403, United States; Furbish, D.J., Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, TN 37235, United States, Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN 37235, United States; Zettler-Mann, A., Department of Geography, University of Oregon, Eugene, OR 97403, United States
推荐引用方式 GB/T 7714	Roth D.L.,Doane T.H.,Roering J.J.,et al. Particle motion on burned and vegetated hillslopes[J],2020,117(41).
APA	Roth D.L.,Doane T.H.,Roering J.J.,Furbish D.J.,&Zettler-Mann A..(2020).Particle motion on burned and vegetated hillslopes.Proceedings of the National Academy of Sciences of the United States of America,117(41).
MLA	Roth D.L.,et al."Particle motion on burned and vegetated hillslopes".Proceedings of the National Academy of Sciences of the United States of America 117.41(2020).