Records of late Quaternary environmental change from high-elevation lakes in the Ruby Mountains and East Humboldt Range, Nevada

2019 ◽  
Author(s):  
Jeffrey S. Munroe ◽  
Matthew F. Bigl ◽  
Annika E. Silverman ◽  
Benjamin J.C. Laabs
Keyword(s):  
Environmental Change ◽  
Late Quaternary ◽  
High Elevation ◽  
Ruby Mountains ◽  
East Humboldt Range

Stable Isotopes in Yellow-Bellied Marmot (Marmota Flaviventris) Fossils Reveal Environmental Stability in the Late Quaternary of the Colorado Rocky Mountains

2015 ◽  
Vol 83 (2) ◽  
pp. 345-354 ◽  
Author(s):  
Linda M. Reynard ◽  
David J. Meltzer ◽  
Steven D. Emslie ◽  
Noreen Tuross
Keyword(s):  
Environmental Change ◽  
Rocky Mountains ◽  
Late Quaternary ◽  
High Elevation ◽  
Environmental Stability ◽  
Bone Collagen ◽  
Marmota Flaviventris ◽  
Mammal Community ◽  
Colorado Rocky Mountains ◽  
Over Time

High elevation plant and animal communities are considered extremely sensitive to environmental change. We investigated an exceptional fossil record of yellow-bellied marmot (Marmota flaviventris) specimens that was recovered from Cement Creek Cave (elev. 2860 m) and ranged in age from radiocarbon background circa 49.8 cal ka BP to ~ 1 cal ka BP. We coupled isotopic and radiocarbon measurements (δ18O, δD, δ15N, δ13C, and 14C) of bone collagen from individually-AMS dated specimens of marmots to assess ecological responses by this species to environmental change over time in a high elevation basin in the Rocky Mountains of southwestern Colorado, USA. We find little change in all four isotope ratios over time, demonstrating considerable environmental stability during periods when the marmots were present. The stable ecology and the apparent persistence of the small mammal community in the cave fauna throughout the late Quaternary are in marked contrast to the changes that occurred in the large mammal community, including local extirpation and extinction, at the end of the Pleistocene.

PRELIMINARY CHEMOSTRATIGRAPHY OF CAVE DEPOSITS IN THE PANTANAL WETLANDS (BRAZIL): INSIGHTS INTO LATE QUATERNARY ENVIRONMENTAL CHANGE

2018 ◽  
Author(s):  
Michael M. McGlue ◽  
◽  
Valdir Felipe Novello ◽  
Francisco W. Cruz ◽  
Rudney de Almeida Santos ◽  
...  
Keyword(s):  
Environmental Change ◽  
Late Quaternary ◽  
Cave Deposits

Elemental proxy evidence for late Quaternary palaeoenvironmental change in southern African sedimentary records: interpretation and applications

2021 ◽  
Author(s):  
M.S. Humphries
Keyword(s):  
Environmental Change ◽  
Southern Africa ◽  
Southern Oscillation ◽  
Late Quaternary ◽  
Rainfall Variability ◽  
Analytical Techniques ◽  
Summer Rainfall ◽  
Geochemical Data ◽  
Complex Nature ◽  
Cape Coast

Abstract Sediments are the most important source of Late Quaternary palaeoclimate information in southern Africa, but have been little studied from a geochemical perspective. However, recent advances in analytical techniques that allow rapid and near-continuous elemental records to be obtained from sedimentary sequences has resulted in the increasing use of elemental indicators for reconstructing climate. This paper explores the diverse information that can be acquired from the inorganic component of sediments and reviews some of the progress that has been made over the last two decades in interpreting the climatic history of southern Africa using elemental records. Despite the general scarcity of elemental records, excellent examples from the region exist, which provide some of the longest and most highly resolved sequences of environmental change currently available. Records from Tswaing crater and marine deposits on the southern KwaZulu-Natal coastline have provided rare glimpses into hydroclimate variability over the last 200 000 years, suggesting that summer rainfall in the region responded predominantly to insolation forcing on glacial-interglacial timescales. Over shorter timescales, lakes and wetlands found in the Wilderness embayment on the southern Cape coast and along the Maputaland coast in north-eastern South Africa have yielded highly-resolved elemental records of Holocene environmental change, providing insight into the changing interactions between tropical (e.g., El Niño-Southern Oscillation) and temperate (e.g., mid-latitude westerlies) climate systems affecting rainfall variability in the region. The examples discussed demonstrate the multiple environmental processes that can be inferred from elemental proxies and the unique insight this can provide in advancing our understanding of past climate change on different timescales. The interpretation of geochemical data can be complicated by the complex nature of sedimentary environments, various proxy assumptions and analytical challenges, and the reliability of sediment-based climate reconstructions is substantially enhanced through multi-proxy approaches.

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