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Full-Text Articles in Physical Sciences and Mathematics

Predictability Of Biomass Burning In Response To Climate Changes, A.-L. Daniau, Megan Walsh Oct 2012

Predictability Of Biomass Burning In Response To Climate Changes, A.-L. Daniau, Megan Walsh

All Faculty Scholarship for the College of the Sciences

Climate is an important control on biomass burning, but the sensitivity of fire to changes in temperature and moisture balance has not been quantified. We analyze sedimentary charcoal records to show that the changes in fire regime over the past 21,000 yrs are predictable from changes in regional climates. Analyses of paleo- fire data show that fire increases monotonically with changes in temperature and peaks at intermediate moisture levels, and that temperature is quantitatively the most important driver of changes in biomass burning over the past 21,000 yrs. Given that a similar relationship between climate drivers and fire emerges from …


Holocene Earthquakes And Late Pleistocene Slip-Rate Estimates On The Wassuk Range Fault Zone, Nevada, J. M. Bormann, Benjamin E. Surpless, M. W. Caffee, S. G. Wesnousky Aug 2012

Holocene Earthquakes And Late Pleistocene Slip-Rate Estimates On The Wassuk Range Fault Zone, Nevada, J. M. Bormann, Benjamin E. Surpless, M. W. Caffee, S. G. Wesnousky

Geosciences Faculty Research

The Wassuk Range fault zone is an 80‐km‐long, east‐dipping, high‐angle normal fault that flanks the eastern margin of the Wassuk Range in central Nevada. Observations from two alluvial fan systems truncated by the fault yield information on the vertical slip rate and Holocene earthquake history along the range front. At the apex of the Rose Creek alluvial fan, radiocarbon dating of offset stratigraphy exposed in two fault trenches shows that multiple earthquakes resulted in 7.0 m of vertical offset along the fault since ∼9400 cal B.P. These data yield a Holocene vertical slip rate of 0.7±0.1  mm/yr. The south trench …


Glacial Lacustrine Records Of Holocene Climate Variations In The Tropical Peruvian Andes, Sasha Rothenberg Jun 2012

Glacial Lacustrine Records Of Holocene Climate Variations In The Tropical Peruvian Andes, Sasha Rothenberg

Honors Theses

Lake sediment cores taken from glacial lakes and wetlands are valuable proxies of glacial activity because they offer a continuous record of sediment input. Tropical alpine glaciers are especially sensitive to changes in precipitation and temperature, and thus the history of glaciation can be used in the reconstruction of past climates. Owing to a steep east-­‐to-­‐west moisture gradient across the Andes, glaciers in the eastern cordillera are more sensitive to changes in temperature whereas those in the drier, western, cordillera are more sensitive to changes in precipitation. Multiple lacustrine sediment cores were taken from two sites in the central Peruvian …


Climate Drivers And Landscape Response: Holocene Fire, Vegetation, And Erosion At City Of Rocks National Reserve, Idaho, Kerrie N. Weppner May 2012

Climate Drivers And Landscape Response: Holocene Fire, Vegetation, And Erosion At City Of Rocks National Reserve, Idaho, Kerrie N. Weppner

Boise State University Theses and Dissertations

Climate exerts primary control over vegetation and fire occurrence but landscape structure, vegetation type, and density determine fire pattern, frequency and severity (i.e., fire regime), and the nature of fire-related geomorphic response. To explore these relationships, we compare alluvial charcoal records of fire and fire-related sedimentation with a woodrat midden reconstruction of vegetation at the northern migration front for single-leaf pinyon and Utah juniper at City of Rocks National Reserve (CIRO), south-central Idaho.

Radiocarbon ages from 37 charcoal macrofossils sampled from discrete fire-related deposits indicate five episodes of increased fire activity over the past ~11 ka. Fires burned following deglaciation …


New Approach On The Saiga Antelopes (Saiga Tatarica/Borealis; Bovidae) From The Late Pleistocene And Holocene Of Crimea (Se Ukraine), Matei M. Vremir Mar 2012

New Approach On The Saiga Antelopes (Saiga Tatarica/Borealis; Bovidae) From The Late Pleistocene And Holocene Of Crimea (Se Ukraine), Matei M. Vremir

Studia UBB Geologia

The present paper is a short review of the knowledge regarding the fossil saiga antelopes from the Pleistocene and Holocene of Crimea, in the context of the general taxonomic and phylogenetic problems in question. According to the newly discovered paleontological material from the Crimean Mountain cave-sites, a new point of view is considered.


Nouvelles Contributions A La Connaisance De L'Histoire De La Vegetation Holocene Des Monts Rodnei (Carpates Orientales), Ioan TanțăU Mar 2012

Nouvelles Contributions A La Connaisance De L'Histoire De La Vegetation Holocene Des Monts Rodnei (Carpates Orientales), Ioan TanțăU

Studia UBB Geologia

New Contributions to the Knowledge of the Holocene Vegetation History of Rodnei Mountains. Two sequences originating from one peat bog in Poiana Ştiol (Rodnei Mts.) were pollen analyzed. The vegetation history is described since the Atlantic period. In this period the vegetation is dominated by Picea together with Corylus, Ulmus and Alnus viridis. The components frequencies of the Quercetum mixtum (Quercus, Fraxinus, Tilia, Corylus) rarely exceed 10%. The vegetation of the Subboreal period is dominated by the Carpinus and that of the Subatlantic is dominated by Fagus. Picea pollen is well represented belong the entire sequences.


Aspects De L'Histoire De La Végétation Tardiglaciaire Et Holocène Dans La Région Des Subcarpates De La Courbure (Subcarpates De Buzau), Ioan TanțăU, Maurice Reille, Sorina FăRcaș, Jacques-Louis De Beaulieu Mar 2012

Aspects De L'Histoire De La Végétation Tardiglaciaire Et Holocène Dans La Région Des Subcarpates De La Courbure (Subcarpates De Buzau), Ioan TanțăU, Maurice Reille, Sorina FăRcaș, Jacques-Louis De Beaulieu

Studia UBB Geologia

A Late Glacial - Holocene sequence from the Bisoca peat bog (Buzăului Subcarpathians) was studied from palynological point of view. The vegetation history, supported by 12 14C dates is described since the end of the Late Glacial. At the onset of the Holocene Ulmus became established by around 9,700 B.P.; Quercus, Fraxinus, Tilia, Corylus became established almost simultaneously by around 9,500 B.P. The local establishment of Carpinus is about 6,200 B.P. Its maximum occurred since 5,000 B.P. Fagus pollen is regularly recorded since 7,000 B.P. Its absolute dominance took place at about 2,000 B.P.


Holocene Climate And Environmental Changes: Disentangling Natural And Anthropogenic Signals In The Sedimentary Record Of Lake Lilandsvatnet (Nw Norway), Robert M. D'Anjou Jan 2012

Holocene Climate And Environmental Changes: Disentangling Natural And Anthropogenic Signals In The Sedimentary Record Of Lake Lilandsvatnet (Nw Norway), Robert M. D'Anjou

Masters Theses 1911 - February 2014

This thesis presents a multi-proxy paleoenvironmental reconstruction from the sedimentary archives of Lilandsvatnet, a small arctic lake on Vestvågøy, in the Lofoten Islands, Norway. Lofoten has a rich history of human settlements existing throughout the Holocene. The catchment of Lilandsvatnet was the location of a prominent Viking chieftain farm that existed throughout the Iron Age, and the sedimentary archive contains a strong signal of prehistoric and historic human settlements and land-use practices. Paleoenvironmental reconstructions in this thesis show evidence for Holocene environmental variability in response to both natural and anthropogenic forcing. Cryptotephra deposits from Icelandic eruptions further contrain sediment chronology …


Holocene Seasonal Variability Inferred From Multiple Proxy Records From Crevice Lake, Yellowstone National Park, Usa, Cathy Whitlock, Walter E. Dean, Sherilyn C. Fritz, Lora R. Stevens, Jeffery R. Stone, Mitchell J. Power, Joseph R. Rosenbaum, Kenneth L. Pierce, Brandi B. Bracht-Flyr Jan 2012

Holocene Seasonal Variability Inferred From Multiple Proxy Records From Crevice Lake, Yellowstone National Park, Usa, Cathy Whitlock, Walter E. Dean, Sherilyn C. Fritz, Lora R. Stevens, Jeffery R. Stone, Mitchell J. Power, Joseph R. Rosenbaum, Kenneth L. Pierce, Brandi B. Bracht-Flyr

Department of Earth and Atmospheric Sciences: Faculty Publications

A 9400-yr-old record from Crevice Lake, a semi-closed alkaline lake in northern Yellowstone National Park, was analyzed for pollen, charcoal, geochemistry, mineralogy, diatoms, and stable isotopes to develop a nuanced understanding of Holocene environmental history in a region of northern Rocky Mountains that receives both summer and winter precipitation. The limited surface area, conical bathymetry, and deep water (>31 m) of Crevice Lake create oxygen-deficient conditions in the hypolimnion and preserve annually laminated sediment (varves) for much of the record. Pollen data indicate that the watershed supported a closed Pinus-dominated forest and low fire frequency prior to 8200 …


Ochotona Daurica Pallas, 1776: Modern And Past Distribution Area In Mongolia And The Transbaikal Region, M. A. Erbjeva, N. V. Alexeeva, T. V. Kisloschaeva Jan 2012

Ochotona Daurica Pallas, 1776: Modern And Past Distribution Area In Mongolia And The Transbaikal Region, M. A. Erbjeva, N. V. Alexeeva, T. V. Kisloschaeva

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Ochotona daurica Pallas, 1776 is one of the ancient species among modern taxa having an origination in Transbaikalia possible at the end of Pleistocene. Review on the Late Pleistocene- Holocene-Recent area of distribution of this species is given on the base of new evidences and detail analysis of the previous data.


Holocene Subsurface Temperature Variability In The Eastern Antarctic Continental Margin, J H Kim, X Crosta, V Willmott, H Renssen, J Bonnin, Peer Helmke, S Schouten, J S Sinninghe Damste Jan 2012

Holocene Subsurface Temperature Variability In The Eastern Antarctic Continental Margin, J H Kim, X Crosta, V Willmott, H Renssen, J Bonnin, Peer Helmke, S Schouten, J S Sinninghe Damste

Research outputs 2012

We reconstructed subsurface (∼45-200m water depth) temperature variability in the eastern Antarctic continental margin during the late Holocene, using an archaeal lipid-based temperature proxy (TEX 86 L). Our results reveal that subsurface temperature changes were probably positively coupled to the variability of warmer, nutrient-rich Modified Circumpolar Deep Water (MCDW, deep water of the Antarctic circumpolar current) intrusion onto the continental shelf. The TEX 86 L record, in combination with previously published climatic records, indicates that this coupling was probably related to the thermohaline circulation, seasonal variability in sea ice extent, sea temperature, and wind associated with high frequency climate dynamics …


A Large Cervidae Holocene Accumulation In Eastern Brazil: An Example Of Extreme Taphonomical Control In A Cave Environment, Alex Hubbe, Augusto S. Auler Jan 2012

A Large Cervidae Holocene Accumulation In Eastern Brazil: An Example Of Extreme Taphonomical Control In A Cave Environment, Alex Hubbe, Augusto S. Auler

International Journal of Speleology

A remarkable cervid bone accumulation occurs at a single passage (named Cervid Passage; CP) at Lapa Nova, a maze cave in eastern Brazil. CP lies away from cave entrances, is a typical pitfall passage and contains bone remains of at least 121 cervids, besides few bats, peccaries and rodents remains. There is no evidence of water (or sediment) flow at the site and in general bones lack post depositional alterations and display anatomical proximity, suggesting that the majority of the remains found inside CP (mainly cervids) are due to animals that after entering the cave got trapped in the site. …


Solar Forcing Of Florida Straits Surface Salinity During The Early Holocene, Matthew W. Schmidt, William A. Weinlein, Franco Marcantonio, Jean Lynch-Stieglitz Jan 2012

Solar Forcing Of Florida Straits Surface Salinity During The Early Holocene, Matthew W. Schmidt, William A. Weinlein, Franco Marcantonio, Jean Lynch-Stieglitz

OES Faculty Publications

Previous studies showed that sea surface salinity (SSS) in the Florida Straits as well as Florida Current transport covaried with changes in North Atlantic climate over the past two millennia. However, little is known about earlier Holocene hydrographic variability in the Florida Straits. Here, we combine Mg/Ca-paleothermometry and stable oxygen isotope measurements on the planktonic foraminifera Globigerinoides ruber (white variety) from Florida Straits sediment core KNR166-2 JPC 51 (24° 24.70' N, 83° 13.14' W, 198 m deep) to reconstruct a high-resolution (~25 yr/sample) early to mid Holocene record of sea surface temperature and δ18OSW)(a …


A New Late Holocene Eolianite Record From Altınkum Beach, North Cyprus, Ahmet Evren Ergi̇nal, Nafi̇ye Güneç Kiyak, Topçu Ahmet Ertek Jan 2012

A New Late Holocene Eolianite Record From Altınkum Beach, North Cyprus, Ahmet Evren Ergi̇nal, Nafi̇ye Güneç Kiyak, Topçu Ahmet Ertek

Turkish Journal of Earth Sciences

In this study, we investigated the main depositional characteristics and obtained Optically Stimulated Luminescence (OSL) ages of coastal eolianite on the north coast of Cyprus, where this occurrence had not previously been recorded. Based on EDX/SEM and XRD data and field observations, the studied eolianite that crops out between elevations of 1 m and 14 m a.s.l. is made up predominantly of quartz grains, most of which consist of medium- to fine-grained sand. The rock comprises aragonite, calcite and quartz with lesser amounts of bornite and hematite as accessory minerals. OSL ages indicated that the initial deposition of eolianite sands …