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Predicting Combined Effects Of Land Use And Climate Change On River And Stream Salinity, John Olson Dec 2018

Predicting Combined Effects Of Land Use And Climate Change On River And Stream Salinity, John Olson

John Olson

Agricultural, industrial and urban development have all contributed to increased salinity in streams and rivers, but the likely effects of future development and climate change are unknown. I developed two empirical models
to estimate how these combined effects might affect salinity by the end of this century (measured as electrical conductivity, EC). The first model predicts natural background from static (e.g. geology and soils) and dynamic
(i.e. climate and vegetation) environmental factors and explained 78% of the variation in EC. I then compared the estimated background EC with current measurements at 2001 sites chosen probabilistically from all conterminous USA streams. …


Belowground Rhizomes In Paleosols: The Hidden Half Of An Early Devonian Vascular Plant, Jinzhuang Xue, Zhenzhen Deng, Pu Huang, Kangjun Huang, Michael J. Benton, Ying Cui Oct 2018

Belowground Rhizomes In Paleosols: The Hidden Half Of An Early Devonian Vascular Plant, Jinzhuang Xue, Zhenzhen Deng, Pu Huang, Kangjun Huang, Michael J. Benton, Ying Cui

Ying Cui

The colonization of terrestrial environments by rooted vascular plants had far-reaching impacts on the Earth system. However, the belowground structures of early vascular plants are rarely documented, and thus the plant−soil interactions in early terrestrial ecosystems are poorly understood. Here we report the earliest rooted paleosols (fossil soils) in Asia from Early Devonian deposits of Yunnan, China. Plant traces are extensive within the soil and occur as complex network-like structures, which are interpreted as representing long-lived, belowground rhizomes of the basal lycopsid Drepanophycus. The rhizomes produced large clones and helped the plant survive frequent sediment burial in well-drained soils …


Input Uncertainty On Watershed Modeling: Evaluation Of Precipitation And Air Temperature Data By Latent Variables Using Swat, Ruoyu Wang Oct 2018

Input Uncertainty On Watershed Modeling: Evaluation Of Precipitation And Air Temperature Data By Latent Variables Using Swat, Ruoyu Wang

Ruoyu Wang

Latent variables (i.e., normally distributed random noise) provide valuable information regarding model input uncertainty. Watershed processes have been explored with sophisticated simulation models in the past few decades and researchers have found that incorporating the uncertainty attributed to forcing inputs, model parameters, and measured data, can help improve simulation results, however, not in all cases. Latent variable use requires careful consideration to determine if results are better or worse. In this study, latent variables were implemented to both precipitation and air temperature data to investigate the influence on model predictions and associated predictive uncertainty by using the Soil and Water …


Edible Forest Gardens- Perennial Ag Fo Eco Regeneration .Pdf, Lisa Depiano Sep 2018

Edible Forest Gardens- Perennial Ag Fo Eco Regeneration .Pdf, Lisa Depiano

Lisa DePiano

A semester long course in Edible Forest Gardening and Perennial Agriculture


Magnetic Properties Of A Sediment Core From Andvord Drift, Emily Youcha, Stefanie A. Brachfeld Aug 2018

Magnetic Properties Of A Sediment Core From Andvord Drift, Emily Youcha, Stefanie A. Brachfeld

Stefanie Brachfeld

No abstract provided.


Magnetic Granulometry Of Igneous And Metasedimentary Rocks From Northern Graham Land, Antarctic Peninsula, Stefanie A. Brachfeld, Anne Grunow, Emily Youcha Aug 2018

Magnetic Granulometry Of Igneous And Metasedimentary Rocks From Northern Graham Land, Antarctic Peninsula, Stefanie A. Brachfeld, Anne Grunow, Emily Youcha

Stefanie Brachfeld

No abstract provided.


Rock-Magnetic Analysis Of Sediments From Andvord Bay, Stefanie A. Brachfeld Aug 2018

Rock-Magnetic Analysis Of Sediments From Andvord Bay, Stefanie A. Brachfeld

Stefanie Brachfeld

No abstract provided.


Multicomponent Cubic Oxide Exsolution In Synthetic Basalts: Temperature Dependence And Implications For Magnetic Properties, Julie A. Bowles, Lisa Tatsumi-Petrochilos, Julie E. Hammer, Stefanie A. Brachfeld Aug 2018

Multicomponent Cubic Oxide Exsolution In Synthetic Basalts: Temperature Dependence And Implications For Magnetic Properties, Julie A. Bowles, Lisa Tatsumi-Petrochilos, Julie E. Hammer, Stefanie A. Brachfeld

Stefanie Brachfeld

Although the compositional unmixing of cubic-structured iron oxides has profound effects on the magnetic properties of rocks that contain them, a basic understanding of the kinetics and thermodynamics of this process has not been achieved in experimental studies due to sluggish reaction rates in binary oxide phases. Exploiting the fact that many natural Fe-oxides contain multiple additional cations, including Ti, Mg and Al, we perform novel “forward” laboratory experiments in which cubic-cubic phase exsolution proceeds from initially homogeneous multicomponent oxides. A variety of Fe-Ti-Mg-Al cubic iron oxides were nucleated and grown in synthetic, multicomponent basalt under different ƒO2 environments, and …


Magnetic And Petrologic Characterization Of Synthetic Martian Basalts And Implications For The Surface Magnetization Of Mars, Julie A. Bowles, Julie E. Hammer, Stefanie A. Brachfeld Aug 2018

Magnetic And Petrologic Characterization Of Synthetic Martian Basalts And Implications For The Surface Magnetization Of Mars, Julie A. Bowles, Julie E. Hammer, Stefanie A. Brachfeld

Stefanie Brachfeld

A suite of synthetic Martian basalts is generated with the objective of providing fundamental material properties data for use in modeling and interpretation of mission data. We systematically evaluate the effects of major element composition, oxygen fugacity (ƒO2), and cooling rate on phase chemistry and magnetic mineralogy, grain size, and intensity of remanent magnetization. The range of experimental compositions and ƒO2 are chosen to bracket the range expected in the Martian crust; our results should therefore span the range of possible mineralogies, textures, and magnetic properties in rapidly cooled Mars crustal materials. Two starting compositions are used for …


Contribution Of Multidomain Titanomagnetite To The Intensity And Stability Of Mars Crustal Magnetic Anomalies, Stefanie A. Brachfeld, David Cuomo, Lisa Tatsumi-Petrochilos, Julie A. Bowles, Deepa Shah, Julie E. Hammer Aug 2018

Contribution Of Multidomain Titanomagnetite To The Intensity And Stability Of Mars Crustal Magnetic Anomalies, Stefanie A. Brachfeld, David Cuomo, Lisa Tatsumi-Petrochilos, Julie A. Bowles, Deepa Shah, Julie E. Hammer

Stefanie Brachfeld

Two basalts with compositions relevant to the crusts of Mars and Earth were synthesized at igneous temperatures and held at 650°C for 21 to 257 days under quartz-fayalite-magnetite ƒO2 buffer conditions. The run products are germane to slowly cooled igneous intrusions, which might be a significant volumetric fraction of the Martian crust and carriers of magnetic anomalies in the Southern Highlands. Both basalts acquired intense thermoremanent magnetizations and intense but easily demagnetized anhysteretic remanent magnetizations carried by homogeneous multidomain titanomagnetite. Hypothetical intrusions on Mars composed of these materials would be capable of acquiring intense remanences sufficient to generate the …


Tiered Approaches In Analyzing Rice Field Pesticide Fate And Transport For Ecological Risk Assessment, Ruoyu Wang Jul 2018

Tiered Approaches In Analyzing Rice Field Pesticide Fate And Transport For Ecological Risk Assessment, Ruoyu Wang

Ruoyu Wang

No abstract provided.


Early Miocene Antarctic Glacial History: New Insights From Heavy Mineral Analysis From Andrill And–2a Drill Core Sediments, Francesco Iacoviello, Giovanna Giorgetti, Isabella Turbanti Memmi, Sandra Passchier Jul 2018

Early Miocene Antarctic Glacial History: New Insights From Heavy Mineral Analysis From Andrill And–2a Drill Core Sediments, Francesco Iacoviello, Giovanna Giorgetti, Isabella Turbanti Memmi, Sandra Passchier

Sandra Passchier

The present study deals with heavy mineral analysis of late Early Miocene marine sediments recovered in the McMurdo Sound region (Ross Sea, Antarctica) during the ANDRILL— SMS Project in 2007. The main objective is to investigate how heavy mineral assemblages reflect different source rocks and hence different provenance areas. These data contribute to a better understanding of East Antarctica ice dynamics in the Ross Sea sector during the Early Miocene (17.6–20.2 Ma), a time of long-term global warming and sea level rise. The AND-2A drill core recovered several stratigraphic intervals that span from Early Miocene to Pleistocene and it collected …


Orbitally Induced Oscillations In The East Antarctic Ice Sheet At The Oligocene/Miocene Boundary, Tim R. Naish, Ken J. Woolfe, Peter J. Barrett, Gary S. Wilson, Cliff Atkins, Steven M. Bohaty, Christian J. Bücker, Michele Claps, Fred J. Davey, Gavin B. Dunbar, Alistair G. Dunn, Christopher R. Fielding, Fabio Florindo, Michael J. Hannah, David M. Harwood, Stuart A. Henrys, Lawrence A. Krissek, Mark Lavelle, Jaap Van Der Meer, William C. Mcintosh, Frank Niessen, Sandra Passchier, Ross D. Powell, Andrew P. Roberts, Leonardo Sagnotti, Reed P. Scherer, C. Percy Strong, Franco Talarico, Kenneth L. Verosub, Giuliana Villa, David K. Watkins, Peter-N. Webb, Thomas Wonik Jul 2018

Orbitally Induced Oscillations In The East Antarctic Ice Sheet At The Oligocene/Miocene Boundary, Tim R. Naish, Ken J. Woolfe, Peter J. Barrett, Gary S. Wilson, Cliff Atkins, Steven M. Bohaty, Christian J. Bücker, Michele Claps, Fred J. Davey, Gavin B. Dunbar, Alistair G. Dunn, Christopher R. Fielding, Fabio Florindo, Michael J. Hannah, David M. Harwood, Stuart A. Henrys, Lawrence A. Krissek, Mark Lavelle, Jaap Van Der Meer, William C. Mcintosh, Frank Niessen, Sandra Passchier, Ross D. Powell, Andrew P. Roberts, Leonardo Sagnotti, Reed P. Scherer, C. Percy Strong, Franco Talarico, Kenneth L. Verosub, Giuliana Villa, David K. Watkins, Peter-N. Webb, Thomas Wonik

Sandra Passchier

Between 34 and 15 million years (Myr) ago, when planetary temperatures were 3-4°C warmer than at present and atmospheric CO2 concentrations were twice as high as today, the Antarctic ice sheets may have been unstable. Oxygen isotope records from deep-sea sediment cores suggest that during this time fluctuations in global temperatures and high-latitude continental ice volumes were influenced by orbital cycles. But it has hitherto not been possible to calibrate the inferred changes in ice volume with direct evidence for oscillations of the Antarctic ice sheets. Here we present sediment data from shallow marine cores in the western Ross …


The Meaning Of Yom In Genesis 1:5, David C. Taylor Jr Jul 2018

The Meaning Of Yom In Genesis 1:5, David C. Taylor Jr

David C Taylor Jr

No abstract provided.


Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna Mar 2018

Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna

Melissa Luna

No abstract provided.


Discovery And Geology Of The Guinness World Record Lake Copper, Lake Superior, Michigan, Theodore J. Bornhorst, Robert Barron Jan 2018

Discovery And Geology Of The Guinness World Record Lake Copper, Lake Superior, Michigan, Theodore J. Bornhorst, Robert Barron

Theodore J. Bornhorst

No abstract provided.


Examining The Use Of Amazon’S Mechanical Turk For Edge Extraction Of The Occlusal Surface Of Fossilized Bovid Teeth, George K. Thiruvathukal, Gregory J. Matthews, Maxwell P. Luetkemeier, Juliet K. Brophy Jan 2018

Examining The Use Of Amazon’S Mechanical Turk For Edge Extraction Of The Occlusal Surface Of Fossilized Bovid Teeth, George K. Thiruvathukal, Gregory J. Matthews, Maxwell P. Luetkemeier, Juliet K. Brophy

George K. Thiruvathukal

In order to reconstruct environments associated with Plio-Pleistocene hominins in southern Africa, researchers frequently rely upon the animals associated with the hominins, in particular, animals in the Family Bovidae. Bovids in southern Africa are typically identified by their teeth. However, identifying the taxon of a bovid tooth is challenging due to various biasing factors. Furthermore, inaccurate identification of fossil bovids can have significant consequences on the reconstructed paleoenvironment. Recent research on the classification of bovid fossil teeth has relied on using elliptical Fourier analysis to summarize the shape of the outline of the occlusal surface of the tooth and the …


Deformation Of Fine-Grained Quartz Aggregates By Mixed Diffusion And Dislocation Creep, Junichi Fukuda, Caleb Holyoke, Andreas Kronenberg Dec 2017

Deformation Of Fine-Grained Quartz Aggregates By Mixed Diffusion And Dislocation Creep, Junichi Fukuda, Caleb Holyoke, Andreas Kronenberg

Caleb Holyoke

No abstract provided.