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Distributed Modeling Of Ablation (1996–2011) And Climate Sensitivity On The Glaciers Of Taylor Valley, Antarctica, Matthew J. Hoffman, Andrew G. Fountain, Glen E. Liston

Geology Faculty Publications and Presentations

The McMurdo Dry Valleys of Antarctica host the coldest and driest ecosystem on Earth, which is acutely sensitive to the availability of water coming from glacial runoff. We modeled the spatial variability in ablation and assessed climate sensitivity of the glacier ablation zones using 16 years of meteorological and surface mass-balance observations collected in Taylor Valley. Sublimation was the primary form of mass loss over much of the ablation zones, except for near the termini where melt, primarily below the surface, dominated. Microclimates in ~10 m scale topographic basins generated melt rates up to ten times higher than over smooth …

Climate, Ecology, And Human Evolution During The Plio-Pleistocene, Scott Adam Blumenthal

Dissertations, Theses, and Capstone Projects

A major goal of paleoanthropology is to identify the selective pressures associated with hominin biological and behavioral evolution, yet establishing cause-effect relationships between climate, ecology, and human evolution remains problematic. This dissertation seeks to investigate hominin paleoecology in eastern Africa by reconstructing aspects of climate and ecology using stable isotope analysis.

The first part of this dissertation is focused on the ecology of primates and hominins. Modern tropical African ecosystems provide a useful model for understanding the ecological correlates of isotopic variation in the fossil record, and living primates provide a useful model for understanding the ecological significance of isotopic …

The Secret Ingredients Of Clover: Biochanin A And Isoflavonoids, Michael Flythe, Glen Aiken, Isabelle Kagan

Kentucky Grazing Conference

It is well known that the value of clover is in nitrogen. Clovers fix their own nitrogen so that an input of nitrate fertilizer is not required. Furthermore, they are rich in protein-nitrogen, and can be used to meet the protein requirements of ruminants. Clovers also contain a class of chemicals called isoflavones, and we have recently discovered evidence that the isoflavones positively influence the way that ruminants digest protein.

Experimental Evidence For Drought Induced Alternative Stable States Of Soil Moisture, David A. Robinson, Scott B. Jones, Inma Lebron, Sabine Reinsch, Maria T. Dominguez, Andrew R. Smith, Davey L. Jones, Miles R. Marshall, Bridget A. Emmett

Plants, Soils, and Climate Faculty Publications

Ecosystems may exhibit alternative stable states (ASS) in response to environmental change. Modelling and observational data broadly support the theory of ASS, however evidence from manipulation experiments supporting this theory is limited. Here, we provide long-term manipulation and observation data supporting the existence of drought induced alternative stable soil moisture states (irreversible soil wetting) in upland Atlantic heath, dominated by Calluna vulgaris (L.) Hull. Manipulated repeated moderate summer drought, and intense natural summer drought both lowered resilience resulting in shifts in soil moisture dynamics. The repeated moderate summer drought decreased winter soil moisture retention by ∼10%. However, intense summer drought, …

Processes Controlling Carbon Cycling In Antarctic Glacier Surface Ecosystems, Elizabeth A. Bagshaw, Martyn Tranter, Jemma L. Wadham, Andrew G. Fountain, A. Dubnick, S. Fitzsimons

Geology Faculty Publications and Presentations

Glacier surface ecosystems, including cryoconite holes and cryolakes, are significant contributors to regional carbon cycles. Incubation experiments to determine the net production (NEP) of organic matter in cryoconite typically have durations of 6-24 hours, and produce a wide range of results, many of which indicate that the system is net heterotrophic. We employ longer term incubations to examine the temporal variation of NEP in cryoconite from the McMurdo Dry Valleys, Antarctica to examine the effect of sediment disturbance on system production, and to understand processes controlling production over the lifetimes of glacier surface ecosystems. The shorter-term incubations have durations of …

Sigma Gamma Epsilon Student Research Poster Session, Geological Society Of America Meeting 2015, Baltimore, Maryland, Usa, Paula Even

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The 2015 Sigma Gamma Epsilon Undergraduate Research (Poster Session) took place during the 2015 Geological Society of America annual meeting in Baltimore, Maryland on Tuesday, 3 November 2015. One hundred-one (101) posters were presented at the SGE poster session. The National Council of Sigma Gamma Epsilon awarded the Austin A. Sartin Best Poster Award to Kayleigh M. Harvey and Carrie A. Menold, students at Albion College. Kate C. Grisi and Michael Cl Rygel, students at State University of New York, College at Potsdam, were awarded the National Council’s Best Poster Award.

Discordant Data And Interpretation Of Results From Wildlife Habitat Models, Anita T. Morzillo, Michael G. Wing, Justin Long

Journal of Geospatial Applications in Natural Resources

Wildlife habitat management is an important part of natural resource management. As a result, there are a large number of models and tools for wildlife habitat assessment. A consequence of the many assessment tools is inconsistency when comparing results between tools, which may lead to potential confusion management decisions. Our objective was to compare results from two wildlife habitat models – one being relatively coarse (HUC5) scale and not spatially dynamic and the other being finer scale spatial data based on a 30 m spatial resolution –for habitat assessment of three species across the West Cascades of Oregon: Northern spotted …

Carbon Isotope Discrimination In C3 Land Plants Is Independent Of Natural Variations In PCo2, M. J. Kohn

Geosciences Faculty Publications and Presentations

The δ¹³C of terrestrial C3 plant tissues and soil organic matter is important for understanding the carbon cycle, inferring past climatic and ecological conditions, and predicting responses of vegetation to future climate change. Plant δ¹³C depends on the δ¹³C of atmospheric CO₂ and and mean annual precipitation (MAP), but an unresolved decades-long debate centres on whether terrestrial C3 plant δ¹³C responds to p_CO2. In this study, the p_CO2-dependence of C3 land plant δ¹³C was tested using isotopic records from low- and high-p_{CO …}

Comparative Analysis Of Xenorhabdus Koppenhoeferi Gene Expression During Symbiotic Persistence In The Host Nematode, Ruisheng An, Parwinder Grewal

School of Earth, Environmental, & Marine Sciences Faculty Publications

Species of Xenorhabdus and Photorhabdus bacteria form mutualistic associations with Steinernema and Heterorhabditis nematodes, respectively and serve as model systems for studying microbe-animal symbioses. Here, we profiled gene expression of Xenorhabdus koppenhoeferi during their symbiotic persistence in the newly formed infective juveniles of the host nematode Steinernema scarabaei through the selective capture of transcribed sequences (SCOTS). The obtained gene expression profile was then compared with other nematode-bacteria partnerships represented by Steinernema carpocapsae-Xenorhabdus nematophila and Heterorhabditis bacteriophora-Photorhabdus temperata. A total of 29 distinct genes were identified to be up-regulated and 53 were down-regulated in X. koppenhoeferi while in S. scarabaei infective …

Experimental Genome-Wide Determination Of Rna Polyadenylation In Chlamydomonas Reinhardtii, Stephen A. Bell, Chi Shen, Alishea Brown, Arthur G. Hunt

Plant and Soil Sciences Faculty Publications

The polyadenylation of RNA is a near-universal feature of RNA metabolism in eukaryotes. This process has been studied in the model alga Chlamydomonas reinhardtii using low-throughput (gene-by-gene) and high-throughput (transcriptome sequencing) approaches that recovered poly(A)-containing sequence tags which revealed interesting features of this critical process in Chlamydomonas. In this study, RNA polyadenylation has been studied using the so-called Poly(A) Tag Sequencing (PAT-Seq) approach. Specifically, PAT-Seq was used to study poly(A) site choice in cultures grown in four different media types—Tris-Phosphate (TP), Tris-Phosphate-Acetate (TAP), High-Salt (HS), and High-Salt-Acetate (HAS). The results indicate that: 1. As reported before, the motif UGUAA is …

Limiting The Impact Of Destructive Analytical Techniques Through Sequential Microspatial Sampling Of The Enamel From Single Teeth, Alexis E. Dolphin, Mathew A. Teeter, Christine D. White, Fred J. Longstaffe

Earth Sciences Publications

A fundamental research concern within contemporary bioarchaeology is the sensitive balance between the preservation of human remains and the use of destructive techniques to collect information. Here we describe one example of how multiple microspatial destructive/semi-destructive techniques may be carried out in sequence using only the enamel of a single tooth. With careful planning of both sample preparation strategies and sequencing of sampling methods, it is possible to produce multiple datasets, and yet to retain material for future analyses.

In this case, enamel from the teeth of 27 individuals who lived during the early medieval period (AD 1170-1198) in Bergen, …

Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Shannon L. Bartelt-Hunt, Xu Li, Matteo D'Alessio, Yun Zhang, Yuping Zhang, J. Brett Sallach

Nebraska Water Center: Faculty Publications

A total of 59 papers published in 2015 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to ecological effects and sampling techniques for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, steroids, antibiotic resistance genes in agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Steroid Hormones, Pharmaceutical Contaminants, Transformation Products, and “Antibiotic Resistance, Drugs, Bugs and Genes”.

The Geologic Context Of Wonderstone: A Complex, Outcrop-Scaled Pattern Of Ironoxide Cement, Derek T. Burgess, Richard M. Kettler, David B. Loope

Department of Earth and Atmospheric Sciences: Faculty Publications

Although siderite is a widespread early diagenetic mineral in fluvial systems, it is unstable in oxidizing environments and destroyed in permeable rocks that experience uplift and exhumation. The products of siderite oxidation, however, (mm- to cm-scale rhombs, concretions, and complex bands of iron-oxide cement) are widespread in the rock record of fluvial systems. The fluvial channels of the Shinarump Member of the Chinle Formation in southern Utah and northern Arizona, U.S.A., provide an excellent suite of examples of diagenetic features produced by Triassic and Neogene oxidation of early diagenetic siderite. These diagenetic features also provide direct evidence of the level …

Expansion Of The Manage Database With Forest And Drainage Studies, Daren R. Harmel, Laura E. Christianson, Matthew W. Mcbroom, Douglas R. Smith, Kori D. Higgs

Faculty Publications

The “Measured Annual Nutrient loads from AGricultural Environments” (MANAGE) database was published in 2006 to expand an early 1980s compilation of nutrient export (load) data from cultivated and pasture/range land at the field or farm scale. Then in 2008, MANAGE was updated with 15 additional studies, and nitrogen (N) and phosphorus (P) concentrations in runoff were added. Since then, MANAGE has undergone significant expansion adding N and P water quality along with relevant management and site characteristic data from: (1) 30 runoff studies from forested land uses, (2) 91 drainage water quality studies from drained land, and (3) 12 additional …

Recent Morphodynamic Evolution Of The Largest Uninhibited Island In The Yangtze (Changjiang) Estuary During 1998-2014: Influence Of The Anthropogenic Interference, Wen Wei, Xuefei Mei, Zhijun Dai, Zhenghong Tang

Community and Regional Planning Program: Faculty Scholarly and Creative Activity

Estuarine geomorphology worldwide has greatly changed in the Anthropocene due to intensive human inferences in river basin and within estuary, which has received increasing global concerns. Here, recent morphodynamic evolution of Jiuduan Shoal (JDS), the largest uninhabited island in the Yangtze (Changjiang) Estuary, and associated controlling factors were analyzed based on unique high-resolution seasonal-surveyed bathymetric data during 1998–2014. It can be indicated that JDS presents novel 12 and 48 months fluctuations though significant accretion was detected on high flats above −2 m. Meanwhile, morphodynamic evolution of JDS during 1998–2014 was divided into three stages: significant siltation on land-ward half of …

Revision Of Polycotylid Plesioaur Systematics (Sauropterygia Plesiosauria) And Description Of The Axial Osteology Of A Juvenile Polycotylid, Donald Joseph Morgan Iii

Theses, Dissertations and Capstones

The polycotylids were a clade of plesiosaurs that proliferated during the Cretaceous period. Despite recent research efforts, evolutionary relationships among polycotylid species remain unresolved. In this study, a phylogenetic analysis incorporating a large taxon sampling from the Polycotylidae was used to parse out the evolutionary relationships among the taxa. The main focus was to assign two polycotylid specimens from the Wallace Ranch to a formal species. A study on the axial osteology of the juvenile Wallace Ranch polycotylid was also performed, as the development of the axial column of a polycotylid plesiosaur has been poorly understood and may have phylogenetic …

Analyzing Pterosaur Ontogeny And Sexual Dimorphism With Multivariate Allometry, Erick Charles Anderson

Theses, Dissertations and Capstones

The relationships of pterosaurs have been previously inferred from observed traits, depositional environments, and phylogenetic associations. A great deal of research has begun to analyze pterosaur ontogeny, mass estimates, wing dynamics, and sexual dimorphism in the last two decades. The latter has received the least attention because of the large data set required for statistical analyses. Analyzing pterosaurs using osteological measurements will reveal different aspects of size and shape variation in Pterosauria (in place of character states) and sexual dimorphism when present. Some of these variations, not easily recognized visually, will be observed using multivariate allometry methods including Principle Component …

A Rapid Physical Habitat Assessment Of Wadeable Streams For Mixed-Land-Use Watersheds, Lynne Hooper, Jason A. Hubbart

Faculty & Staff Scholarship

Mitigating stream and river impairment is complex, particularly in mixed-land-use watersheds given the likelihood of integrated responses of stream restoration to coupled and ongoing terrestrial ecosystem disturbance and the need for periodic reassessment and maintenance. Traditional biological sampling (e.g., macroinvertebrate sampling or other biological indices) alone seldom identifies the cause of biological community impairment and large fiscal investments are often made with no apparent improvement to aquatic ecosystem health. A stream physical habitat assessment (PHA) can yield information that, when paired with land-use data may reveal causal patterns in aquatic physical habitat degradation and help to identify sites for rehabilitation …

The Spatial Sensitivity Analysis Of Evapotranspiration Using Penman-Monteith Method At Grid Scale, Sivarajah Mylevaganam, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

The need to allocate the existing water in a sustainable manner, even with the projected population growth, has made to assess the consumptive use or evapotranspiration (ET), which determines the irrigation demand. As underscored in the literature, Penman-Monteith method which is a combination of aerodynamic and energy balance method is widely used and accepted as the method of estimation of ET. However, the application of Penman-Monteith relies on many climate parameters such as relative humidity, solar radiation, temperature, and wind speed. Therefore, there exists a need to determine the parameters that are most sensitive and correlated with dependent variable ( …

Great South Bay, Long Island, New York Summer Water Quality Monitoring Program, Cercom, Molloy University, John Tanacredi Ph.D., Sixto E. Portilla

CERCOM Reports

In 2016 the Center for Environmental Research and Coastal Oceans Monitoring (CERCOM) visited 9 locations in Great South Bay to monitor for dissolved oxygen (DO), pH, salinity, clarity, depth and temperature. This monitoring program has been conducted for the past 14 years. These parameters are critical in determining long-term water quality conditions in Long Island estuaries. Methodologies for monitoring parameters are provided by the Standard Methods for the Examination of Water and Wastewater 20th Edition (1998). Criteria for determining water quality conditions in marine eco-systems are based on the type of contact (uses) people have with the water system. The …

A New Radiometric Date And Assessment Of The Last Glacial Megafauna Of Dream Cave, Derbyshire, Uk, Donald A. Mcfarlane, Joyce Lundberg, Guy Van Rentergem, Eliza Howlett, Chris Stimpson

KGI Faculty Publications and Research

The extinct fauna of Dream Cave, Derbyshire, has played a significant role in the history of British cave paleontology, a near-complete woolly rhinoceros from the cave having been famously illustrated in 1823. The fauna was not subsequently re-studied until 2000, with the publication of an indirect radiometric date by uranium-series disequilibrium dating of a presumed-overlying flowstone. Here we present a direct radiocarbon date of 43,330 +/- 1800 rcyBP, 45083 - 48613 calBP (1 σ) on a representative Bos/Bison bone, with additional comments on the fauna and the taphonomy of the site.

Source Apportionment Of Atmospheric Particulate Matter In Developing Countries Using Trace Elements And Stable Metal Isotope Ratios, Nitika Dewan

Electronic Theses and Dissertations

The work presented herein details the source apportionment of atmospheric particulate matter in developing countries (Kyrgyzstan in Central Asia, metropolitan cities in Northern India, and Shenzhen in China) using trace elements and stable metal isotope ratios. The first study focused on the development of a novel method for the concomitant separation of rare-earth elements in environmental samples of any geological origin. The separation procedure is based on three extraction chromatographic materials, referred to as Sr.Spec, TRU.Spec, and Ln.Spec. This triple column arrangement enables the simultaneous isolation of pure Sr and Nd fractions in less than one day and with great …

Ua24 Mcicsl Newsletter - January 2016, Shannon R. Trimboli Education Coordinator

MCICSL Newsletter

This issue includes the following:

Information about the upcoming 11th Research Symposium

New Stonefly species

Winter Bat Monitoring

as well as research highlights and education highlights

Rangeland Responses To Predicted Increases In Drought Extremity, David D. Breshears, Alan K. Knapp, Darin J. Law, Melinda D. Smith, Dirac L. Twidwell, Carissa L. Wonkka

National Drought Mitigation Center: Faculty Publications

Rangeland managers actively focus on the potential to induce a shift in a site to an alternative state, but predicted changes in climate, particularly the likelihood of more extreme drought, necessitate reevaluating risks for alternative states. • Rangelands will differ in their susceptibility to undergo state changes due to climate change in general and for droughts of the future, in particular, which may be hotter. • Trees, shrubs, and grasses are expected to differ in their sensitivity to drought, with trees likely being most sensitive; this affects the likelihood for state changes in grasslands, shrublands, woodlands, and savannas. • Considering …

Assortative Mating But No Evidence Of Genetic Divergence In A Species Characterized By A Trophic Polymorphism, Scott F. Coborne, S R. Garner, Fred Longstaffe, Bryan D. Neff

Earth Sciences Publications

Disruptive selection is a process that can result in multiple sub-groups within a population, referred to as diversification. Foraging related divergence has been described in many taxa, but many questions remain about the contribution of such divergence to reproductive isolation and potentially sympatric speciation. Here we use stable isotope analysis of diet and morphological analysis of body shape to examine phenotypic divergence between littoral and pelagic foraging ecomorphs in a population of pumpkinseed sunfish (Lepomis gibbosus). We then examine reproductive isolation between ecomorphs by comparing the isotopic compositions of nesting males to eggs from their nests (a proxy for maternal …

Microbially Induced Sedimentary Structures In The Paleoproterozoic, Upper Huronian Supergroup, Canada, Carolyn Hill, Patricia I. Corcoran, Rohan Aranha, Fred Longstaffe

Earth Sciences Publications

The Paleoproterozoic Gordon Lake and Bar River formations, Huronian Supergroup, contain a variety of sedimentary structures in the Flack Lake area of Ontario, Canada, that have been considered of debatable origin. We identify these structures as microbially induced sedimentary structures (MISS). The preserved MISS are related to microbial mat destruction and decay, and include sand cracks, mat chips, remnant gas domes, pyrite patches, and iron laminae. A biological origin for the fossil structures is supported by their similarities to modern and ancient documented examples of MISS, the sand-dominated nature of the substrate in which they are preserved, and key microtextures …

Dentine Oxygn Isotopes (Δ18o) As A Proxy For Odontocete Distributions And Movements., Cory J.D. Matthews, Fred J. Longstaffe, Steven H. Fergispm

Earth Sciences Publications

Spatial variation in marine oxygen isotope ratios ( δ¹⁸O) resulting from differential evaporation rates and precipitation inputs is potentially useful for characterizing marine mammal distributions and tracking movements across δ¹⁸O gradients. Dentine hydroxyapatite contains carbonate and phosphate that precipitate in oxygen isotopic equilibrium with body water, which in odontocetes closely tracks the isotopic composition of ambient water. To test whether dentine oxygen isotope composition reliably records that of ambient water and can therefore serve as a proxy for odontocete distribution and movement patterns, we measured δ¹⁸O values of dentine structural carbonate (δ^{18 …}

Early Horizon Camelid Management Practices In The Nepeña Valley, North-Central Coast Of Peru, Paul Szpak, David Chicone, Jean-François Millaire, Christine D. White, Rebecca Parry, Fred Longstaffe

Earth Sciences Publications

South American camelids (llamas and alpacas) were of great economic, social and ritual significance in the pre-Hispanic Andes. Although these animals are largely limited to high-altitude (>3500 masl) pastures, it has been hypothesised that camelids were also raised at lower altitudes in the arid coastal river valleys. Previous isotopic studies of Early Intermediate Period (c. 200 BC - AD 600) and Middle Horizon (c. AD 600 - 1100) camelids support this argument. Here, we utilise carbon and nitrogen isotopic analyses of camelid bone collagen from the Early Horizon (c. 800 - 200 BC) sites of Caylán and Huambacho on …

Alpha-Lipoic Acid Supplementation Protects Enzymes From Damage By Nitrosative And Oxidative Stress, Sylvia Hiller, Robert Dekroon, Eric D. Hamlett, Longquan Xu, Cristina Osorio, Jennifer Robinette, Witold Winnik, Stephen Simington, Nobuyo Maeda, Oscar Alzate, Xianwen Yi

United States Environmental Protection Agency: Publications

Background: S-nitrosylation of mitochondrial enzymes involved in energy transfer under nitrosative stress may result in ATP deficiency. We investigated whether α-lipoic acid, a powerful antioxidant, could alleviate nitrosative stress by regulating S-nitrosylation,which could result in retaining themitochondrial enzyme activity.

Methods: In this study, we have identified the S-nitrosylated forms of subunit 1 of dihydrolipoyllysine succinyltransferase (complex III), and subunit 2 of the α-ketoglutarate dehydrogenase complex by implementing a fluorescence-based differential quantitative proteomics method.

Results: We found that the activities of these two mitochondrial enzymes were partially but reversibly inhibited by S-nitrosylation in cultured endothelial cells, and that their activities …

Seasonality Of Coliform Bacteria Detection Rates In New Jersey Domestic Wells, Thomas B. Atherholt, Nicholas A. Procopio, Sandra M. Goodrow

United States Environmental Protection Agency: Publications

It is important that indicators of fecal pollution are reliable. Coliform bacteria are a commonly used indicator of fecal pollution. As other investigators have reported elsewhere, we observed a seasonal pattern of coliform bacteria detections in domestic wells in New Jersey. Examination of a statewide database of 10 years of water quality data from 93,447 samples, from 78,207 wells, generated during real estate transactions, revealed that coliform bacteria were detected in a higher proportion of wells during warm weather months. Further examination of the seasonal pattern of other data, including well water pH, precipitation, ground and surface water temperatures, surface …