气候变化领域集成服务门户(CCPortal): Arrested development: Erosional equilibrium in the southern Sierra Nevada, California, maintained by feedbacks between channel incision and hillslope sediment production

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DOI	10.1130/B35006.1
	Arrested development: Erosional equilibrium in the southern Sierra Nevada, California, maintained by feedbacks between channel incision and hillslope sediment production
	Callahan R.P.; Ferrier K.L.; Dixon J.; Dosseto A.; Hahm W.J.; Jessup B.S.; Miller S.N.; Hunsaker C.T.; Johnson D.W.; Sklar L.S.; Riebe C.S.
发表日期	2019
ISSN	167606
起始页码	1179
结束页码	1202
卷号	131 期号:2021-07-08
英文摘要	Tributary creeks of the southern Sierra Nevada have pronounced knickpoints that separate the landscape into an alternating sequence of gently sloped treads and steeply sloped risers. These knickpoints and the surrounding "stepped topography" suggest that the landscape is still responding to Pleistocene changes in base level on mainstem rivers. We tested this hypothesis using cosmogenic nuclides and uranium isotopes measured in stream sediment from widely distributed locations. Catchment-scale erosion rates from the cosmogenic nuclides suggest that the treads are relict surfaces that have adjusted to a previous base level. Nevertheless, erosion rates of relict interfluves are similar to canyon incision rates, implying that relief is unchanging in the lower Kings and San Joaquin Rivers. In addition, our results suggest that much of the southern Sierra Nevada is in a state of arrested development: the landscape is not fully adjusted to-and moreover is not responding to- changes in base-level lowering in the canyons. We propose that this can be explained by a paucity of coarse sediment supply, which fails to provide sufficient tools for bedrock channel incision at knickpoints. We hypothesize that the lack of coarse sediment in channels is driven by intense weathering of the local granitic bedrock, which reduces the size of sediment supplied from hillslopes to the channels. Our analysis highlights a feedback in which sediment size reduction due to weathering on hillslopes and transport in channels is both a key response to and control of bedrock channel incision and landscape adjustment to base-level change. © 2019 Geological Society of America.
语种	英语
来源期刊	Bulletin of the Geological Society of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/184943
作者单位	Department of Geology and Geophysics, University of Wyoming, Laramie, WY 82071, United States; Wyoming Center for Environmental Hydrology and Geophysics, University of Wyoming, Laramie, WY 82071, United States; School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, United States; Department of Geoscience, University of Wisconsin, Madison, WI 53706, United States; Department of Earth Sciences, Montana State University, Bozeman, MT 59717, United States; Wollongong Isotope Geochronology Laboratory, School of Earth and Environmental Sciences, University of Wollongong, Wollongong, NSW 2522, Australia; Department of Earth and Planetary Science, University of California, Berkeley, CA 94720, United States; Department of Ecosystem Science and Management, University of Wyoming, Laramie, WY 82071, United States; Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture, Fresno, CA 93710, United States; Department of Natural Resources and Enviro...
推荐引用方式 GB/T 7714	Callahan R.P.,Ferrier K.L.,Dixon J.,et al. Arrested development: Erosional equilibrium in the southern Sierra Nevada, California, maintained by feedbacks between channel incision and hillslope sediment production[J],2019,131(2021-07-08).
APA	Callahan R.P..,Ferrier K.L..,Dixon J..,Dosseto A..,Hahm W.J..,...&Riebe C.S..(2019).Arrested development: Erosional equilibrium in the southern Sierra Nevada, California, maintained by feedbacks between channel incision and hillslope sediment production.Bulletin of the Geological Society of America,131(2021-07-08).
MLA	Callahan R.P.,et al."Arrested development: Erosional equilibrium in the southern Sierra Nevada, California, maintained by feedbacks between channel incision and hillslope sediment production".Bulletin of the Geological Society of America 131.2021-07-08(2019).