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Selective Capture Of Transcribed Sequences: A Promising Approach For Investigating Bacterium-Insect Interactions, Ruisheng An, Parwinder Grewal Jan 2012

Selective Capture Of Transcribed Sequences: A Promising Approach For Investigating Bacterium-Insect Interactions, Ruisheng An, Parwinder Grewal

School of Earth, Environmental, & Marine Sciences Faculty Publications

Bacterial interactions with eukaryotic hosts are complex processes which vary from pathogenic to mutualistic. Identification of bacterial genes differentially expressed in the host, promises to unravel molecular mechanisms driving and maintaining such interactions. Several techniques have been developed in the past 20 years to investigate bacterial gene expression within their hosts. The most commonly used techniques include in-vivo expression technology, signature-tagged mutagenesis, differential fluorescence induction, and cDNA microarrays. However, the limitations of these techniques in analyzing bacterial in-vivo gene expression indicate the need to develop alternative tools. With many advantages over the other methods for analyzing bacterial in-vivo gene expression, …


The Interrelationship Between The Bio- And Sequence Stratigraphy Of The Middle Cambrian Spence Shale Of Northern Utah And Southern Idaho, Eva Lyon Dec 2011

The Interrelationship Between The Bio- And Sequence Stratigraphy Of The Middle Cambrian Spence Shale Of Northern Utah And Southern Idaho, Eva Lyon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This project was undertaken with the objective of discerning the relationship between sea level change and changes in the fauna of the Spence Shale. A combination of field and lab work was employed to undertake this research. The Spence Shale is rich in fossils from the earliest period of visible life on this planet. It provides a unique window onto the evolution of life and changes in the Earth at this time. It is important to study this relationship between sea level and life changes as these conditions are constantly changing, particularly in this day and age. A better understanding …


Taking “Grazing” To The Next Level, Edward N. Ballard Oct 2011

Taking “Grazing” To The Next Level, Edward N. Ballard

Kentucky Grazing Conference

Since the late 1980’s, producer awareness of pasture management has been increasing. A number of factors have brought this about. Mainly, economic conditions have forced producers to look at their bottom line and this has reflected the low returns from mismanagement of forages and pastures. Also, advancements in the technology of pasture management and improvement have made more intensive utilization of the forage resource more economically viable. Advances in equipment, especially fencing and water equipment, have also helped bring about the increased interest in better grassland management.


Extreme Variation In The Sagittal Crest Of Tapirus Polkensis (Mammalia Perissodactyla) At The Gray Fossil Site Northeastern Tn., Aaron Randall Abernethy Aug 2011

Extreme Variation In The Sagittal Crest Of Tapirus Polkensis (Mammalia Perissodactyla) At The Gray Fossil Site Northeastern Tn., Aaron Randall Abernethy

Electronic Theses and Dissertations

The preservation and quantity of fossil tapirs (Tapirus polkensis) from the Gray Fossil Site in northeastern Tennessee provides a unique opportunity for comparison and analysis of skeletal characters. Intraspecifically, modern tapirs show little to no variation in the morphology of the sagittal crest. However, several different morphologies exist within the sample at Gray. No osteological evidence of sexual dimorphism exists for tapirs, and no correlation between crest shape and sex was observed. Several juveniles display well defined crests, while some adults have only minor thickening of the temporal ridges; therefore, no distinct correlation between age and crest state …


No-Net-Loss Not Met For Nutrient Function In Freshwater Marshes: Recommendations For Wetland Mitigation Policies, Katie Hossler, Virginie Bouchard, M. Siobhan Fennessy, Serita D. Frey, Evelyn Anemaet, Ellen Herbert Jul 2011

No-Net-Loss Not Met For Nutrient Function In Freshwater Marshes: Recommendations For Wetland Mitigation Policies, Katie Hossler, Virginie Bouchard, M. Siobhan Fennessy, Serita D. Frey, Evelyn Anemaet, Ellen Herbert

Faculty Publications

Wetlands provide many important services throughout the world, with an estimated economic value that, in comparison to other ecosystems, far exceeds their relatively small global extent. In recognition of their importance, both national and international regulations exist to protect the world's remaining wetlands. Of growing interest is the “no-net-loss” policy which permits unavoidable destruction of wetlands if compensated by restoration of degraded wetlands or creation of new wetlands. The fundamental assumption of no-net-loss is that wetlands can be created which function equivalently to natural wetlands. One integral function that wetlands perform is cycling of carbon, nitrogen and phosphorus. Here we …


Evaluation Of Algorithm Thresholds For Crop Canopy Sensor-Based In-Season Nitrogen Application In Corn, Brian Theodore Krienke Jul 2011

Evaluation Of Algorithm Thresholds For Crop Canopy Sensor-Based In-Season Nitrogen Application In Corn, Brian Theodore Krienke

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Nitrogen fertilizer is frequently the most limiting nutrient in corn production. Typically most nitrogen is applied before planting. Since nitrogen can leave the soil system fairly easily, the result can be an inefficient use of nitrogen fertilizer. Previous research has shown increased efficiency with no reduction in yield by applying nitrogen later in the season when the crop is actively growing, with rates regulated spatially through the use of active crop canopy sensors. This study evaluated the potential for N cutoff thresholds using a sufficiency index as the threshold value for areas with poor stand or an unrecoverable N deficiency. …


Comparison Of Soil Chemistry And Microbial Communities That Inhabit The Rhizosphere Of Native And Non-Native Grasses Of The Lower Rio Grande Valley, Jacqueline Valencia Jul 2011

Comparison Of Soil Chemistry And Microbial Communities That Inhabit The Rhizosphere Of Native And Non-Native Grasses Of The Lower Rio Grande Valley, Jacqueline Valencia

Theses and Dissertations - UTB/UTPA

Non-native grasses can modify the soils they invade. This study investigated microbial variation among native and non-native grasses in the Lower Rio Grande Valley. We hypothesized that rhizospheres of non-native grasses would support a higher density of microorganisms; therefore microbial communities of invasive plants would exploit more carbon sources than those of native plants. A second hypothesis stated that Streptomyces bacteria from the rhizosphere of non-native grasses would be better competitors. Samples of grasses, and soil from their respective rhizospheres were obtained in Arroyo City, TX. Results indicated a higher bacterial colony density, total activity and number of substrates utilized …


Growing The Urban Ecosystem In Detroit, Michigan, Sean Basalyga May 2011

Growing The Urban Ecosystem In Detroit, Michigan, Sean Basalyga

Social Sciences

Many views of the future are seen as bleak and devoid of the life where once stood beauty and abundance. However, the Living Cities Design Competition challenges these views and calls for a vision of the future that inspires hope, biodiversity, and a healthy interaction between human and natural systems. We chose to redesign the city of Detroit, Michigan to be a living city by the year 2035. As the earth scientist on an interdisciplinary team, I acted as an ecological consultant. By developing the urban ecosystem of Detroit, a number of social, economical, and environmental problems can be solved. …


On The Cranial Osteology Of Eremiascincus And Its Use For Identification., William B. Gelnaw May 2011

On The Cranial Osteology Of Eremiascincus And Its Use For Identification., William B. Gelnaw

Electronic Theses and Dissertations

A persistent problem for Australian paleontology has been a lack of diagnostic characters for identifying lizard fossils. Eremiascincus is one of the most widespread genera in Australia, so it was examined for distinguishing features and how it fits into a model of skink evolution. Skulls of Eremiascincus were examined within five separate contexts: 1) a description of the cranial osteology, 2) a qualitative comparison of individual cranial elements of Eremiascincus to closely related Ctenotus, 3) a description of the cranial allometry in Eremiascincus using linear morphometrics, 4) using cranial morphometrics of skinks to deduce their phylogeny, and 5) using …


The Occurrence Of An Abdominal Fauna In An Articulated Tapir (Tapirus Polkensis) Recovered From The Miocene Gray Fossil Site Northeast Tennessee., Shannon M. Mcconnell May 2011

The Occurrence Of An Abdominal Fauna In An Articulated Tapir (Tapirus Polkensis) Recovered From The Miocene Gray Fossil Site Northeast Tennessee., Shannon M. Mcconnell

Electronic Theses and Dissertations

The analysis of samples recovered from the abdominal area of an articulated tapir from the Late Miocene (4.5-7 million bp) Gray Fossil Site, revealed a rich palyno-fauna comprised of about 94% egg/oocyst-like structures and 6% pollen and other palynomorphs. In addition, a tight grouping of six hickory nuts (Carya) was recovered from the same area suggesting that the samples represent the abdominal contents. The analysis of a sample from immediately outside the tapir produced a sample with 98% pollen and less than 0.5% egg-like structures. The size, shape, and general morphology of egg-like structures were analyzed with light …


Effects Of Rodent Species, Seed Species, And Predator Cues On Seed Fate, Kelly J. Sivy, Steven M. Ostoja, Eugene W. Schupp, Susan Durham Apr 2011

Effects Of Rodent Species, Seed Species, And Predator Cues On Seed Fate, Kelly J. Sivy, Steven M. Ostoja, Eugene W. Schupp, Susan Durham

United States Geological Survey: Staff Publications

Seed selection, removal and subsequent management by granivorous animals is thought to be a complex interaction of factors including qualities of the seeds themselves (e.g., seed size, nutritional quality) and features of the local habitat (e.g. perceived predator risk). At the same time, differential seed selection and dispersal is thought to have profound effects on seed fate and potentially vegetation dynamics. In a feeding arena, we tested whether rodent species, seed species, and indirect and direct predation cues influence seed selection and handling behaviors (e.g., scatter hoarding versus larder hoarding) of two heteromyid rodents, Ord’s kangaroo rat (Dipodomys ordii) and …


Alfalfa Hay For Horses: Myths Vs. Reality, Laurie Lawrence Feb 2011

Alfalfa Hay For Horses: Myths Vs. Reality, Laurie Lawrence

Kentucky Alfalfa and Stored Forage Conference

Does it really matter if hay has some mold in it?

Hay that is high in dust or mold can irritate the horse’s respiratory tract. Optimum athletic performance depends on a healthy respiratory tract, therefore dusty/moldy hay should never be fed to horses used (or intended for) athletic events. A chronic respiratory disease commonly called “heaves” can be aggravated by moldy and dusty hay. Horses with heaves can have so much difficulty breathing that even mild exercise is impossible. In addition, moldy hay may contain toxins that could affect the horse if they are ingested.

Horse owners should not rely …


Crop Updates 2011 - Nutrition, Precision Agriculture & Climate And Forecasting, Deb Archdeacon, Andrew Gulliver, David Cullen, Qifu Ma, Richard Bell, Ross Brennan, Craig Scanlan, Wen Chen, Geoff Anderson, Mike Bolland, Peter Rees, Sandy Alexander, Frank D'Emden, Stephen Davies, Breanne Best, Louise Barton, Klaus Butterbach-Bahl, Ralph Kiese, Daniel Murphy, Peter Newman, Roger Mandel, Roger Lawes, Michael Robertson, Derk Bakker, Jeremy Lemon, Alison Lacey, John Paul Collins, Glen Riethmuller, Fiona H. Evans, David Stephens, Caroline Peek, Tim Scanlon Feb 2011

Crop Updates 2011 - Nutrition, Precision Agriculture & Climate And Forecasting, Deb Archdeacon, Andrew Gulliver, David Cullen, Qifu Ma, Richard Bell, Ross Brennan, Craig Scanlan, Wen Chen, Geoff Anderson, Mike Bolland, Peter Rees, Sandy Alexander, Frank D'Emden, Stephen Davies, Breanne Best, Louise Barton, Klaus Butterbach-Bahl, Ralph Kiese, Daniel Murphy, Peter Newman, Roger Mandel, Roger Lawes, Michael Robertson, Derk Bakker, Jeremy Lemon, Alison Lacey, John Paul Collins, Glen Riethmuller, Fiona H. Evans, David Stephens, Caroline Peek, Tim Scanlon

Crop Updates

This session covers sixteen papers from different authors:

Nutrition

1. Balance® used in conventional cropping practice with half of the upfront fertiliser rate can sustain crop yield and build soil biological fertility, Deb Archdeacon1, Andrew Gulliver2 and David Cullen2, 1Agronomica, Wellington Mill, WA, 2Custom Composts, Nambeelup, WA

2. Effects of potassium (K) supply on plant growth, potassium uptake and grain Yield in wheat grown in grey sand, Qifu Ma1, Richard Bell1, Ross Brennan2 and Craig Scanlan2, 1School of Environmental Science, Murdoch University, 2Department of Agriculture and Food

3. Improving fertiliser management: redefining the …


Crop Updates 2011 - Cereals, David Bowran, Bill Crabtree, Peter Carberry, Peter Burges, Bevan Buirchell, Ben Curtis, Sarah Ellis, Brenda Shackley, Christine Zaicou, Siva Sivapalan, Penny Goldsmith, Gae Plunkett, Darshan Sharma, Mario D'Antuono, Art Diggle, Peter Mangano, Sally Peltzer, Michael Renton, Bill Macleod, Fumie Horiuchi, George Wyatt, Geoff Anderson, Richard Bell, Ross Brennan, Wen Chen, Penny Riffkin Feb 2011

Crop Updates 2011 - Cereals, David Bowran, Bill Crabtree, Peter Carberry, Peter Burges, Bevan Buirchell, Ben Curtis, Sarah Ellis, Brenda Shackley, Christine Zaicou, Siva Sivapalan, Penny Goldsmith, Gae Plunkett, Darshan Sharma, Mario D'Antuono, Art Diggle, Peter Mangano, Sally Peltzer, Michael Renton, Bill Macleod, Fumie Horiuchi, George Wyatt, Geoff Anderson, Richard Bell, Ross Brennan, Wen Chen, Penny Riffkin

Crop Updates

This session covers eleven papers from different authors:

OPENING, NEW CROP VARIETIES & DECISION SUPPORT

Opening

1. Overview of the 2010 season, David Bowran, Director, Practice and Systems Innovation, Department of Agriculture and Food,

2. My experience in a drought as a farmer and consultant, Bill Crabtree, Morawa, Western Australia

3. Meeting the productivity and sustainability challenges to Australian agriculture until 2030, Peter Carberry, CSIRO Sustainable Agriculture Flagship

New Crop Varieties

4. National Variety Trials (NTV) wheat variety performance – captivity vs broadacre, Peter Burgess, Kalyx Agriculture

5. WALAN2289 – a new lupin variety to replace …


Greener Pastures 4 - Managing Potassium In Dairy Pastures, Mike Bolland, Ian Guthridge, Bill Russell, Martin Staines, John Lucey, Richard Morris Feb 2011

Greener Pastures 4 - Managing Potassium In Dairy Pastures, Mike Bolland, Ian Guthridge, Bill Russell, Martin Staines, John Lucey, Richard Morris

Bulletins 4000 -

We undertook three studies into the potassium requirements of high rainfall pastures: 1. Between 1999 and 2009, soil testing was conducted in 48 dairy paddocks at Vasse Research Centre (VRC) in the south-west of Western Australia (WA). This study will be referred to as the VRC soil test study.

2. Between 2002 and 2007, a potassium experiment was undertaken at Boyanup to improve our knowledge of potassium requirements of intensively grazed ryegrass pastures. This will be referred to as the Boyanup potassium experiment.

3. Between 2006 and 2010, potassium experiments were undertaken on two partner farms of the Greener Pastures …


Greener Pastures 3 - Managing Phosphorus In Dairy Pastures, Mike Bolland, Ian Guthridge, Bill Russell, Martin Staines, John Lucey, Richard Morris Feb 2011

Greener Pastures 3 - Managing Phosphorus In Dairy Pastures, Mike Bolland, Ian Guthridge, Bill Russell, Martin Staines, John Lucey, Richard Morris

Bulletins 4000 -

Between 1999 and 2009, soil testing was conducted in 48 dairy paddocks at Vasse Research Centre (VRC) in the south-west of Western Australia (WA). This study will be referred to as the VRC soil test study.

Phosphorus experiments were undertaken on partner farms of the Greener Pastures project to improve our knowledge of the phosphorus requirements of intensively grazed ryegrass pastures. These are the partner farm phosphorus experiments.


Greener Pastures 1 - The Greener Pasture Project: Managing Nutrients In Dairy Pastures, John Lucey, Mike Bolland, Don Bennett, Richard Morris, Bill Russell, Martin Staines Feb 2011

Greener Pastures 1 - The Greener Pasture Project: Managing Nutrients In Dairy Pastures, John Lucey, Mike Bolland, Don Bennett, Richard Morris, Bill Russell, Martin Staines

Bulletins 4000 -

As dairy farmers have strived to maintain profitability, many have farmed more intensively. More cows are milked and increasing inputs of fertiliser and purchased feed are used per hectare. However, these increased nutrient inputs have far exceeded the increase in nutrient output in milk production. The increasing nutrient surplus (inputs minus outputs) from intensification on dairy farms has met with increasing community concern about the environmental footprint of the dairy industry. In some other countries, dairy farmers who have intensified by increasing nitrogen inputs are now faced with legislation controlling the amount of fertiliser nitrogen that they can use.

The …


Greener Pastures 2 - Nitrogen For Intensively Grazed Dairy Pastures, Martin Staines, Richard Morris, Tess Casson, Mike Bolland, Bill Russell, Ian Guthridge, John Lucey, Don Bennett Feb 2011

Greener Pastures 2 - Nitrogen For Intensively Grazed Dairy Pastures, Martin Staines, Richard Morris, Tess Casson, Mike Bolland, Bill Russell, Ian Guthridge, John Lucey, Don Bennett

Bulletins 4000 -

We undertook three main studies during the Greener Pastures project:

1. From mid 2005 to late 2008, a farming systems study was undertaken with five rates of nitrogen fertiliser as the main treatment. This study will be referred to as the ‘nitrogen response farmlets’.

2. From 2006 to 2008 a series of smaller ‘supporting’ studies were completed to investigate how grazing management influences the pasture production gains from nitrogen fertiliser. This will be referred to as the ‘nitrogen by growth-stage study’.

3. From early 2009 to early 2010, a farming systems study was undertaken to investigate the potential to increase …


Extended Grazing And Reduced Stored Feed, Edward N. Ballard Jan 2011

Extended Grazing And Reduced Stored Feed, Edward N. Ballard

Kentucky Grazing Conference

Feed costs represent the major cost in most livestock production systems. A recently completed analysis of 225 Standardized Performance Analysis (SPA) Beef Cow Records on herds in Illinois and Iowa showed that feed cost was the overriding factor determining profitability, explaining over 57 percent of the herd-to-herd variation. Typically the cost of supplying nutrients to ruminant livestock is much greater using harvested feedstuffs as opposed to grazing pastures or crop residues. The primary function of a grassland farm is to convert solar energy to marketable livestock products in the most efficient manner. The fewer steps between the animal product and …


Grazing Non-Traditional Forages, Jeff Mccutcheon Jan 2011

Grazing Non-Traditional Forages, Jeff Mccutcheon

Kentucky Grazing Conference

In the Heart of America region we are blessed with perennial cool-season grasses and legumes as the bulk of our forage production. Efficiently taking advantage of that perennial production is the focus of most grazing operations. Occasionally there are times when the production from our cool- season grass and legume pasture is not sufficient. In Ohio, that is late summer and late fall through winter till early spring. Nontraditional forages could be used when cool season forages are not producing. Non-traditional forages can provide a large volume, of high-quality feed during specific times of the year.


Mob Grazing, High Density Grazing, Management-Intensive Grazing: What's The Difference?, Mark Kennedy Jan 2011

Mob Grazing, High Density Grazing, Management-Intensive Grazing: What's The Difference?, Mark Kennedy

Kentucky Grazing Conference

Before we can answer that question we need to review some basic fundamentals of successful grazing management. Four goals of any sustainable grazing management strategy should be: 1) Meet the nutritional needs of livestock from standing pasture as many days as possible; 2) Optimize pasture yield, quality and persistence; 3) Maintain or enhance the natural resource base; 4) Integrate the appropriate technology and knowledge into a practical and profitable system that fits your available resources and meets your objectives. We will use these goals to compare and contrast these 2 grazing management techniques. Both techniques should be considered tools in …


How Much Pasture Do I Have And How Long Will It Feed My Cows?, S. Ray Smith Jan 2011

How Much Pasture Do I Have And How Long Will It Feed My Cows?, S. Ray Smith

Kentucky Grazing Conference

A very common question asked by cattlemen is, “How much pasture do I have and how long will it feed my cows.” The purpose of this paper is to provide some guidelines and tools for answering this question. In pasture systems, determining the amount of pasture is much harder than in grain-based feeding systems because feed may be allocated for more than one day and feed quantity and quality is influenced by weather, fertility, stand density, and season. In addition, not all the available forage is consumed and the plants continue to grow after they are grazed. Variation in quality …


Foreword And Conference Information [2011], Garry D. Lacefield, Christi L. Forsythe Jan 2011

Foreword And Conference Information [2011], Garry D. Lacefield, Christi L. Forsythe

Kentucky Grazing Conference

No abstract provided.


Reproduction And Genetic Detection Of Veligers In Changing Dreissena Populations In The Great Lakes, Jeffrey L. Ram, Aos S. Karim, Payel Acharya, Pranav Jagtap, Sonal Purohit, Donna R. Kashian Jan 2011

Reproduction And Genetic Detection Of Veligers In Changing Dreissena Populations In The Great Lakes, Jeffrey L. Ram, Aos S. Karim, Payel Acharya, Pranav Jagtap, Sonal Purohit, Donna R. Kashian

Environmental Science and Geology Faculty Research Publications

Dreissenid bivalves, Dreissena polymorpha (zebra mussel) and Dreissena bugensis (quagga mussel) are biofouling species that invaded the Great Lakes region of North America from source populations in Europe in the 1980s. Initially, D. polymorpha spread faster and farther; however, D. bugensis have recently displaced D. polymorpha in many areas of the Great Lakes and was the first to be found west of the Continental Divide. Early detection of dreissenids is important in anticipating and preventing potentially high economic impacts. To study population dynamics and to enhance detection methods, we assessed “spawnability” using a serotonin bioassay and developed a new, sensitive, …


Temperature Increase Effects On Sagebrush Ecosystem Forbs: Exprimental Evidence And Range Manager Perspectives, Hilary Louise Whitcomb Jan 2011

Temperature Increase Effects On Sagebrush Ecosystem Forbs: Exprimental Evidence And Range Manager Perspectives, Hilary Louise Whitcomb

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Selenium In Birds, Harry M. Ohlendorf, Gary H. Heinz Jan 2011

Selenium In Birds, Harry M. Ohlendorf, Gary H. Heinz

United States Geological Survey: Staff Publications

Selenium (Se) is a metalloid trace element that birds and other wildlife need in small amounts for good health. The main purpose of this chapter is to interpret tissue concentrations of Se. However, because food is the main source of Se accumulation for birds and other wildlife, and because dietary concentrations for effects on bird reproduction have been reported, we also provide interpretive information on Se in the diet.

Se deficiencies in domestic poultry and livestock occur in some parts of the world and must be corrected by additions of Se to the diet. However, the range of dietary concentrations …


Foliar Nutrient Concentrations Related To Soil Sources Across A Range Of Sites In The Northeastern United States, Melissa S. Lucash, Ruth D. Yanai, Joel D. Blum, B. B. Park Jan 2011

Foliar Nutrient Concentrations Related To Soil Sources Across A Range Of Sites In The Northeastern United States, Melissa S. Lucash, Ruth D. Yanai, Joel D. Blum, B. B. Park

Environmental Science and Management Faculty Publications and Presentations

Understanding the supply of nutrients from various soil sources and the sensitivity of tree species to soil nutrient availability is critical for predicting the effects of declines in base cations due to acid rain and forest harvesting on forest health and productivity. We collected soil samples from 19 sites in the northeastern United States, chemically analyzed them using a sequential extraction procedure, and compared them to the chemical composition of foliage of the dominant tree species. Concentrations of Ca and Mg in foliage were correlated with exchangeable Ca and Mg concentrations in the upper mineral soil; for most tree species …


Early Season Depletion Of Dissolved Iron In The Ross Sea Polynya: Implications For Iron Dynamics On The Antarctic Continental Shelf, Peter N. Sedwick, C. M. Marsay, B. M. Sohst, A. M. Aguilar-Islas, M. C. Lohan, M. C. Long, K. R. Arrigo, R. B. Dunbar, M. A. Saito, W. O. Smith, G. R. Ditullio Jan 2011

Early Season Depletion Of Dissolved Iron In The Ross Sea Polynya: Implications For Iron Dynamics On The Antarctic Continental Shelf, Peter N. Sedwick, C. M. Marsay, B. M. Sohst, A. M. Aguilar-Islas, M. C. Lohan, M. C. Long, K. R. Arrigo, R. B. Dunbar, M. A. Saito, W. O. Smith, G. R. Ditullio

OES Faculty Publications

The Ross Sea polynya is among the most productive regions in the Southern Ocean and may constitute a significant oceanic CO2sink. Based on results from several field studies, this region has been considered seasonally iron limited, whereby a "winter reserve" of dissolved iron (dFe) is progressively depleted during the growing season to low concentrations (~ 0.1 nM) that limit phytoplankton growth in the austral summer (December-February). Here we report new iron data for the Ross Sea polynya during austral summer 2005-2006 (27 December-22 January) and the following austral spring 2006 (16 November-3 December). The summer 2005-2006 data show …


Fungal Communities On Speleothem Surfaces In Kartchner Caverns, Arizona, Usa., Michael J. Vaughan, Raina M. Maier, Barry M. Pryor Jan 2011

Fungal Communities On Speleothem Surfaces In Kartchner Caverns, Arizona, Usa., Michael J. Vaughan, Raina M. Maier, Barry M. Pryor

International Journal of Speleology

Kartchner Caverns, located near Benson, Arizona, USA, is an active carbonate cave that serves as the major attraction for Kartchner Caverns State Park. Low-impact development and maintenance have preserved prediscovery macroscopic cavern features and minimized disturbances to biological communities within the cave.. The goal of this study was to examine fungal diversity in Kartchner Caverns on actively-forming speleothem surfaces. Fifteen formations were sampled from five sites across the cave. Richness was assessed using standard culture-based fungal isolation techniques. A culture-independent analysis using denaturing gradient gel electrophoresis (DGGE) was used to assay evidence of community homogeneity across the cave through the …


Methylmercury In Mosquitoes: Impact Of A Large Coal-Fired Power Station In Central Ohio, Matthew J. Konkler Jan 2011

Methylmercury In Mosquitoes: Impact Of A Large Coal-Fired Power Station In Central Ohio, Matthew J. Konkler

Browse all Theses and Dissertations

Emissions from coal-fired utilities are the major anthropogenic source of mercury (Hg) to the atmosphere. Because emitted Hg may be deposited near the source, there are concerns on levels of toxic monomethylmercury (MeHg) in local biota. We investigated the potential impact of a large Hg-emitting (> 500 kg Hg y-1) coal-fired power station on MeHg levels in mosquitoes near the Conesville power station in central Ohio. Mosquitoes were sampled with CO2-baited traps at 23 locations within a 60 km radius of the utility and at three reference sites distant from Hg combustion sources. MeHg in mosquitoes within a 30-km radius …