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Open Data And Digital Morphology, Thomas G. Davies, Imran A. Rahman, Stephan Lautenschlager, John A. Cunningham, Robert J. Asher, Paul M. Barrett, Karl T. Bates, Stefan Bengtson, Roger B. J. Benson, Doug M. Boyer, José Braga, Jen A. Bright Apr 2017

Open Data And Digital Morphology, Thomas G. Davies, Imran A. Rahman, Stephan Lautenschlager, John A. Cunningham, Robert J. Asher, Paul M. Barrett, Karl T. Bates, Stefan Bengtson, Roger B. J. Benson, Doug M. Boyer, José Braga, Jen A. Bright

School of Geosciences Faculty and Staff Publications

Over the past two decades, the development of methods for visualizing and analysing specimens digitally, in three and even four dimensions, has transformed the study of living and fossil organisms. However, the initial promise that the widespread application of such methods would facilitate access to the underlying digital data has not been fully achieved. The underlying datasets for many published studies are not readily or freely available, introducing a barrier to verification and reproducibility, and the reuse of data. There is no current agreement or policy on the amount and type of data that should be made available alongside studies …


Earth News, V40, Spring 2017, University Of Northern Iowa. Department Of Earth And Environmental Sciences. Apr 2017

Earth News, V40, Spring 2017, University Of Northern Iowa. Department Of Earth And Environmental Sciences.

Earth News

Inside this issue:
-- From the Department Head Siobahn Morgan
-- Department Growth
-- Faculty Updates
-- SGE Newsletter
-- Congratulations 2016
-- Sunday at the Quarry
-- Alumni Spotlight: Aaron Stolley
-- Alumni Spotlight: Allyson Anderson
-- Congratulations to Faculty
-- Carver Grants
-- Hydrology News
-- Student Research
-- Donor Spotlight: Leslie Knapp


Actively Forming Kuroko-Type Volcanic-Hosted Massive Sulfide (Vhms) Mineralization At Iheya North, Okinawa Trough, Japan, Christopher J. Yeats, Steven P. Hollis, Angela Halfpenny, Juan-Carlos Corona, Crystal Laflamme, Gordon Southam, Marco Fiorentini, Richard J. Herrington, John Spratt Apr 2017

Actively Forming Kuroko-Type Volcanic-Hosted Massive Sulfide (Vhms) Mineralization At Iheya North, Okinawa Trough, Japan, Christopher J. Yeats, Steven P. Hollis, Angela Halfpenny, Juan-Carlos Corona, Crystal Laflamme, Gordon Southam, Marco Fiorentini, Richard J. Herrington, John Spratt

All Faculty Scholarship for the College of the Sciences

Modern seafloor hydrothermal systems provide important insights into the formation and discovery of ancient volcanic-hosted massive sulfide (VHMS) deposits. In 2010, Integrated Ocean Drilling Program (IODP) Expedition 331 drilled five sites in the Iheya North hydrothermal field in the middle Okinawa Trough back-arc basin, Japan. Hydrothermal alteration and sulfide mineralization is hosted in a geologically complex, mixed sequence of coarse pumiceous volcaniclastic and fine hemipelagic sediments, overlying a dacitic to rhyolitic volcanic substrate. At site C0016, located adjacent to the foot of the actively venting North Big Chimney massive sulfide mound, massive sphalerite-(pyrite-chalcopyrite ± galena)-rich sulfides were intersected (to 30.2% …


Groundwater And Tidal Controls On Wetland Hydrology, Julie J. Metz Wetland Mitigation Bank, Woodbridge, Virginia, Benjamin Stuart Hiza Apr 2017

Groundwater And Tidal Controls On Wetland Hydrology, Julie J. Metz Wetland Mitigation Bank, Woodbridge, Virginia, Benjamin Stuart Hiza

OES Theses and Dissertations

Julie J. Metz Wetlands Mitigation Bank, a 92-hectare freshwater wetland located in Woodbridge, Virginia, borders the tidally-influenced Neabsco Creek. Seven pods separated by earthen berms were built by Wetland Studies and Solutions Inc. (WSSI) in 1995 and 1997 by removing the toe of small sandy alluvial fans and covering the underlying coarse gravel bed with a low permeability cap. The basal Quaternary gravels were deposited in a creek valley incised into a thick sand-and-clay Cretaceous delta. The alluvial-fan apron developed at the base of steep slopes along the sides of the valley. Pressure transducer data from five monitoring wells along …


Factors That Influence Vital Rates Of Seaside And Saltmarsh Sparrows In Coastal New Jersey, Usa, Samuel G. Roberts, Rebecca A. Longenecker, Matthew A. Etterson, Katharine J. Ruskin, Chris S. Elphick, Brian J. Olsen, W. Gregory Shriver Mar 2017

Factors That Influence Vital Rates Of Seaside And Saltmarsh Sparrows In Coastal New Jersey, Usa, Samuel G. Roberts, Rebecca A. Longenecker, Matthew A. Etterson, Katharine J. Ruskin, Chris S. Elphick, Brian J. Olsen, W. Gregory Shriver

United States Environmental Protection Agency: Publications

As saltmarsh habitat continues to disappear, understanding the factors that influence the population dynamics of saltmarsh breeding birds is an important step in the conservation of these declining species. Using 5 yrs (2011–2015) of demographic data, we evaluated and compared apparent adult survival and nest survival of Seaside (Ammodramus maritimus) and Saltmarsh (A. caudacutus) sparrows at the Edwin B. Forsythe National Wildlife Refuge in New Jersey, USA. We determined the effect of site management history (unditched vs. ditched marshes) on adult and nest survival to aid in prioritizing future management or restoration actions. Apparent adult …


Dynamics Of Nitrate, Phosphorus, And Suspended Sediment Transport In Two Agricultural Streams In Central Illinois, Luke W. Lampo Mar 2017

Dynamics Of Nitrate, Phosphorus, And Suspended Sediment Transport In Two Agricultural Streams In Central Illinois, Luke W. Lampo

Theses and Dissertations

Nutrients such as nitrate and phosphorus are necessary for life, but excessive amounts can be detrimental. Large amounts of nutrients entering bodies of water can lead to hypoxic zones such as the one in the Gulf of Mexico. Nutrients are also problematic in drinking water reservoirs, as high concentrations of nitrate in drinking water can cause health conditions such as blue baby syndrome and high phosphorus concentrations can lead to algal blooms. Suspended sediment leads to reservoir sedimentation, habitat degradation, and is able to transport particulate nutrients. High nutrient and sediment concentrations are a recurring problem in the drinking water …


Oysters And Mammoths: Fossils In Central Texas–Texas Academy Of Science 2017, Chris Barker, R. Larell Nielson Mar 2017

Oysters And Mammoths: Fossils In Central Texas–Texas Academy Of Science 2017, Chris Barker, R. Larell Nielson

Faculty Publications

Texas Academy of Science, 2017 Field Trip

This year's Texas Academy of Science Geology Field Trip takes you to two very different fossil sites in central Texas. Stop 1 is along a quiet road in the Hill Country where you can collect abundant invertebrate fossils from the Lower Cretaceous Comanche Peak Limestone and Walnut Clay. The second stop of the trip is at one of the newest units of America's park service: the Waco Mammoth National Monument. At this site you will see a spectacular fossil discovery that is now one of the main mammoth sites in North America. And …


Effects Of Anthropogenic Activity On The Green Swamp Preserve Ecosystem, Barbara Ann Nordheim-Shelt Mar 2017

Effects Of Anthropogenic Activity On The Green Swamp Preserve Ecosystem, Barbara Ann Nordheim-Shelt

USF Tampa Graduate Theses and Dissertations

The Green Swamp Preserve is a large geographic area that has sustained many changes since Europeans settled in Florida. There has been little published research on the impacts of anthropogenic activity on this system. This thesis research seeks to document more recent changes in the Green Swamp and to evaluate the effects of various human activities on the system. The study period is from 1985 to 2015. For this time period changes in land use and landcover were examined using neural network classifications. Changes in vegetation health were evaluated by examining Normalized Difference Vegetation Index (NDVI) and Green Vegetation Index …


The Dynamic Geomorphic Setting Of The Late Pleistocene Hartley Mammoth Site: Burial And Skeletal Preservation In A Slump-Block Depression Near Abiquiu, New Mexico, Jennifer K. Muus Mar 2017

The Dynamic Geomorphic Setting Of The Late Pleistocene Hartley Mammoth Site: Burial And Skeletal Preservation In A Slump-Block Depression Near Abiquiu, New Mexico, Jennifer K. Muus

Earth and Planetary Sciences ETDs

Near Abiquiu in northern New Mexico, the skeletal remains of two mammoths were discovered in the summer of 2014 in the near-surface deposits of a very small alluvial channel. The channel occupies a depression on the backtilted top of a Toreva slump block, a highly unusual setting for a mammoth burial. Geomorphological investigation of the site has provided insight into processes leading to burial and preservation of the remains, as well as local environmental change. Field mapping of sediment sources and LiDAR scans of the contributing slope basin and slump bench provided a map of geomorphic features and surficial geologic …


Geoengineering, Marine Microalgae, And Climate Stabilization In The 21st Century, Charles H. Greene, Mark E. Huntley, Ian Archibald, Léda N. Gerber, Deborah L. Sills, Joe Granados, Colin M. Beal, Michael J. Walsh Mar 2017

Geoengineering, Marine Microalgae, And Climate Stabilization In The 21st Century, Charles H. Greene, Mark E. Huntley, Ian Archibald, Léda N. Gerber, Deborah L. Sills, Joe Granados, Colin M. Beal, Michael J. Walsh

Natural & Applied Sciences Faculty Publications

Society has set ambitious targets for stabilizing mean global temperature. To attain these targets, it will have to reduce CO2 emissions to near zero by mid-century and subsequently remove CO2 from the atmosphere during the latter half of the century. There is a recognized need to develop technologies for CO2 removal; however, attempts to develop direct air-capture systems have faced both energetic and financial constraints. Recently, BioEnergy with Carbon Capture and Storage (BECCS) has emerged as a leading candidate for removing CO2 from the atmosphere. However, BECCS can have negative consequences on land, nutrient, and water use as well as …


Weathering In Iowa: Not What You May Think, Alexa Sedlacek Mar 2017

Weathering In Iowa: Not What You May Think, Alexa Sedlacek

UNIversitas: Journal of Research, Scholarship, and Creative Activity

When I look at the limestone bedrock of Iowa, as I did just the other day with my daughter (figure 2—[credit: Aaron Spurr, Quarry October 2, 2016]), I see long-term carbon storage. I do not mean a place to sequester modern atmospheric CO2 into the subsurface. Rather, limestones in Iowa and around the world represent carbon that was removed from the atmosphere through geologic processes and stored in these carbonate rocks. Carbon storage in rocks such as limestone and fossil fuels are responsible for the large scale changes in atmospheric CO2 concentrations throughout Earth’s history.


Unique Preservation Of Fossil Ghost Fish In The Green River Formation, Amanda L. Meacham Mar 2017

Unique Preservation Of Fossil Ghost Fish In The Green River Formation, Amanda L. Meacham

Loma Linda University Electronic Theses, Dissertations & Projects

Two beds with unique fossil fish preservation occur within the predominantly evaporite-rich, fossil poor Angelo Member in the Green River Formation in Fossil Basin, Wyoming. These two beds, termed “Ghost Fish” beds, contain fossil fish that are two-dimensional carbonaceous compressions with no bone and detailed soft part preservation. These beds were measured and samples were collected from 8 quarries and 19 additional locations. Stratigraphic sections and fossil content were recorded at each quarry location. Analysis included XRD, stable isotope, XRF, TOC, and SEM analysis. Results were inputted into tables, graphs, and spatial maps to show trends, interpret the paleoenvironment, and …


Diversity Of Deep-Sea Fishes Of The Easter Island Ecoregion, Erin E. Easton, Javier Sellanes, Carlos F. Gaymer, Naiti A. Morales, Matthias Gorny, Eric Berkenpas Mar 2017

Diversity Of Deep-Sea Fishes Of The Easter Island Ecoregion, Erin E. Easton, Javier Sellanes, Carlos F. Gaymer, Naiti A. Morales, Matthias Gorny, Eric Berkenpas

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Easter Island Ecoregion is in the center of the South Pacific gyre and experiences ultra-oligotrophic conditions that could make it highly susceptible to global change and anthropogenic activities, so it is imperative that these regions are characterized and studied so that conservation and sustainable management strategies can be developed. From the few studies from the region, we know that the coastal areas are relatively depauperate and have relatively high rates of endemism. Here, we present a brief report from the first video observations from this region of the deep-dwelling fishes from ROV exploration of benthic communities from …


Nutrient Contamination From Non-Point Sources: Dissolved Phosphate In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Hunter R. Evans, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone Mar 2017

Nutrient Contamination From Non-Point Sources: Dissolved Phosphate In Surface And Subsurface Waters At Eku Meadowbrook Farm, Madison County, Kentucky, Hunter R. Evans, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone

EKU Faculty and Staff Scholarship

Farms are non-point sources for nutrient contaminants that drain into watersheds and contribute to eutrophication and other environmental problems. Eastern Kentucky University’s Meadowbrook Farm raises both crops and livestock, causing dissolved phosphorus in the form of orthophosphate (PO43-) from fertilizer and animal manure to enter surface and subsurface waters, eventually flowing into Muddy Creek, a tributary of the Kentucky River.

We sampled surface water, springs, and water from French drains that emanate from the farm, and also sampled Muddy Creek waters from May through August 2016. Typically, 1 to 2 days after sampling, we colorimetrically measured dissolved …


Scaling And Functional Morphology In Strigiform Hind Limbs, Meen A. Madan, Emily J. Rayfield, Jen A. Bright Mar 2017

Scaling And Functional Morphology In Strigiform Hind Limbs, Meen A. Madan, Emily J. Rayfield, Jen A. Bright

School of Geosciences Faculty and Staff Publications

Strigiformes are an order of raptorial birds consisting exclusively of owls: the Tytonidae (barn owls) and the Strigidae (true owls), united by a suite of adaptations aiding a keen predatory lifestyle, including robust hind limb elements modified for grip strength. To assess variation in hind limb morphology, we analysed how the dimensions of the major hind limb elements in subfossil and modern species scaled with body mass. Comparing hind limb element length, midshaft width, and robusticity index (RI: ratio of midshaft width to maximum length) to body mass revealed that femoral and tibiotarsal width scale with isometry, whilst length scales …


Recruitment Patterns Of Juvenile Fish At An Artificial Reef Area In The Gulf Of Mexico, Rachel Noel Arney, Catheline Y. M. Froehlich, Richard Kline Mar 2017

Recruitment Patterns Of Juvenile Fish At An Artificial Reef Area In The Gulf Of Mexico, Rachel Noel Arney, Catheline Y. M. Froehlich, Richard Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

In 2011 the Texas Parks and Wildlife Department and the Coastal Conservation Association of Texas deployed over 4,000 concrete culverts in a designated artificial reef area off Port Mansfield, Texas, to enhance habitat for sport fish species in the Gulf of Mexico. A study was conducted to assess juvenile fish recruitment at varying culvert densities within the artificial reef area. Standard monitoring units for the recruitment of reef fish (SMURFs) were used to sample juvenile fish, and these collections were compared with visual scuba surveys. The 0.027-m3 SMURFs were placed at four different culvert densities (0, 1–50, 51–100, and 101+ …


Selecting Summer Annual Varieties Using Yield And Digestibility, Christopher D. Teutsch Feb 2017

Selecting Summer Annual Varieties Using Yield And Digestibility, Christopher D. Teutsch

Kentucky Alfalfa and Stored Forage Conference

Although cool-season grasses can provide ample and high quality forage for grazing livestock in the spring and fall, forage growth during the summer months is often restricted by high temperatures (Figure 1). In contrast warm-season annual grasses are most productive during the summer months and do not reach peak growth until temperatures approach 90 degrees Fahrenheit. Summer annual grasses such as forage sorghum (Sorghum bicolor (L.) Moench), sudangrass (Sorghum bicolor (L.) Moench), sorghum-sudangrass hybrids, and pearl millet (Pennisetum americanum (L.) Leeke) can provide high quality summer grazing for ruminant livestock in many regions of the United States.


The Economics Of Hay Quality, Madeline L. Dant, Kenneth H. Burdine, Brandon Sears Feb 2017

The Economics Of Hay Quality, Madeline L. Dant, Kenneth H. Burdine, Brandon Sears

Kentucky Alfalfa and Stored Forage Conference

Hay quality is often discussed when one considers the viability of cash hay operations. A great deal is known about how production impacts quality and how quality impacts animal performance. This knowledge certainly has economic implications, but the economics of hay quality has primarily been evaluated from the animal performance perspective. Analyzing the economics of hay quality from the cash hay producer’s prospective becomes more difficult due to data limitations.

There are approximately 2.5 million acres of hay produced in Kentucky annually. The vast majority of this hay is grass type hay that is produced and fed on beef cattle …


Western Hay Production Vs. Eastern Hay Production, Tom Keene Feb 2017

Western Hay Production Vs. Eastern Hay Production, Tom Keene

Kentucky Alfalfa and Stored Forage Conference

Early in the history of mankind, man was nomadic and moved from location to location in order to gather and find sustenance for themselves as well as their livestock. At some point in time, man decided that rather than keep moving, they would establish a community in one location, usually near running water (or fresh water of some kind), and would begin to sustain themselves with production agricultural practices.

Planting and harvesting soon took the place of packing up and moving every time the current resources had been depleted. Each year a new crop would be planted; livestock also became …


Why Is Intake Reduced When Cattle Are Fed Tall Fescue?, James L. Klotz Feb 2017

Why Is Intake Reduced When Cattle Are Fed Tall Fescue?, James L. Klotz

Kentucky Alfalfa and Stored Forage Conference

A major problem for the cattle producer that utilizes tall fescue forage is the unrealized or reduced gains in body weight in growing animals. This result has been reproduced across numerous studies evaluating cattle performance on tall fescue (Hoveland et al., 1983; Boling, 1985; Schmidt et al., 1986; Goetsch et al., 1987). Cattle have gained from 30 to 100% less consuming toxic endophyte-infected tall fescue compared to consumption of an endophyte-free tall fescue (Paterson et al., 1995). This effect of reduced gain is a consequence of a fungal endophyte present within the grass that produces toxins called ergot alkaloids. Fungal …


Understanding And Improving Fermentation In Alfalfa And Grass Baleage, Dennis Hancock Feb 2017

Understanding And Improving Fermentation In Alfalfa And Grass Baleage, Dennis Hancock

Kentucky Alfalfa and Stored Forage Conference

The ancient Egyptian and Carthaginians are believed to be the first conserve forage by ensiling it in the absence of oxygen. Though the technique has been refined in the 3500 years since, the basic fermentation process has not changed. Populations of naturally-occurring bacteria on the plant surface can consume some of the readily available carbohydrates and produce organic acids. These organic acids lower the pH of the forage material and prevent fungal deterioration of the product. Fermentation has been used for millennia as a natural method for preserving food. Similar bacterial fermentation occurs when one makes yogurt, sour cream, or …


Ergot And Loline Alkaloid Concentrations In Endophyte-Infected Tall Fescue Tillers, Rebecca L. Mcculley Feb 2017

Ergot And Loline Alkaloid Concentrations In Endophyte-Infected Tall Fescue Tillers, Rebecca L. Mcculley

Forage Climate Change Experiment Research Data

Approximately 40 tall fescue tillers were randomly collected and frozen from each of the 20 treatment plots.

Tillers were cut at 7.6 cm above ground level and tested for the presence of the Epichloe endophyte using an enzyme-linked immunosorbent assay.

Tillers from each plot were sorted into 'infected' vs 'uninfected' groups, lyophilized, and ground through a 1mm screen using a Cyclotec 1093 mill.

Ground material from the endophyte infected tillers was analyzed for ergot and loline alkaloids in the lab of Lowell Bush at the University of Kentucky, Plant and Soil Sciences Dept.

For details on alkaloid analyses see: McCulley …


Multiple Metabolisms Constrain The Anaerobic Nitrite Budget In The Eastern Tropical South Pacific, Andrew R. Babbin, Brian D. Peters, Calvin W. Mordy, Brittany Widner, Karen L. Casciotti, Bess B. Ward Feb 2017

Multiple Metabolisms Constrain The Anaerobic Nitrite Budget In The Eastern Tropical South Pacific, Andrew R. Babbin, Brian D. Peters, Calvin W. Mordy, Brittany Widner, Karen L. Casciotti, Bess B. Ward

OES Faculty Publications

The Eastern Tropical South Pacific is one of the three major oxygen deficient zones (ODZs) in the global ocean and is responsible for approximately one third of marine water column nitrogen loss. It is the best studied of the ODZs and, like the others, features a broad nitrite maximum across the low oxygen layer. How the microbial processes that produce and consume nitrite in anoxic waters interact to sustain this feature is unknown. Here we used 15N-tracer experiments to disentangle five of the biologically mediated processes that control the nitrite pool, including a high-resolution profile of nitrogen loss rates. …


High Prevalence Of Toxigenic Clostridium Difficile In Public Space Lawns In Western Australia, Peter Moono, Su Chen Lim, Thomas V. Riley Feb 2017

High Prevalence Of Toxigenic Clostridium Difficile In Public Space Lawns In Western Australia, Peter Moono, Su Chen Lim, Thomas V. Riley

Research outputs 2014 to 2021

Clostridium difficile is a well-established hospital pathogen. Recently, it has been detected increasingly in patients without hospital contact. Given this rise in community associated infections with C. difficile, we hypothesized that the environment could play an important role in transmission of spores outside the hospital. Lawn samples (311) collected in public spaces in the metropolitan area of Perth, Western Australia, from February to June 2016 were cultured for C. difficile. C. difficile was isolated from the samples by direct and enrichment culture, and characterized by standard molecular methods using toxin gene PCR and ribotyping. The overall prevalence of …


Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti Jan 2017

Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti

International Journal of Speleology

Over the past 15 years several expeditions by French, American and especially Italian cavers have unveiled over 50 caves in the Cordillera de la Sal (Atacama Desert, Northern Chile). Many of these caves contain a variety of speleothems and minerals, some of which have rarely been observed within karst systems. Most of the secondary deposits in these caves are composed of halite, but also other halide, carbonate, sulphate, nitrate, phosphate, and silicate minerals have been found. Among the sixteen cave mineral species recognized, atacamite, darapskite, blödite, leonite, anhydrite, and especially antarcticite are worth mentioning. In one of the samples an …


Effects Of Litter On Seedling Emergence And Seed Persistence Of Three Common Species On The Loess Plateau In Northwestern China, Rui Zhang, Xiaowen Hu, Jerry M. Baskin, Carol C. Baskin, Yanrong Wang Jan 2017

Effects Of Litter On Seedling Emergence And Seed Persistence Of Three Common Species On The Loess Plateau In Northwestern China, Rui Zhang, Xiaowen Hu, Jerry M. Baskin, Carol C. Baskin, Yanrong Wang

Biology Faculty Publications

Litter accumulation resulting from land use change (enclosure) is one of the key variables influencing seedling recruitment and consequently the regeneration of plant populations and seed persistence in the soil seed bank. A better understanding of the effects of litter on seed germination and seedling emergence is crucial for developing a new set of indicators for grassland ecosystem health and for grassland management policy. We investigated the effects of seed position in litter and amount of litter covering the seed on seedling emergence and seed persistence of three common species on the Loess Plateau in northwestern China. Seed position beneath …


Cover Crops And Tillage Management For Enhanced Sustainability In Corn/Soybean Production In The Mississippi Delta Region Of Arkansas, David Scott Patton Jan 2017

Cover Crops And Tillage Management For Enhanced Sustainability In Corn/Soybean Production In The Mississippi Delta Region Of Arkansas, David Scott Patton

Student Theses and Dissertations

A field experiment was established during 2014 in Northeast Arkansas to evaluate the benefits of cover crop and tillage management for enhanced yield and soil quality. Cover crop management included cereal rye, wheat and crimson clover, and a winter fallow. Tillage management included tillage and no-tillage. In the 2015 and 2016 seasons yield was not significantly changed by different tillage treatments. Cover crop out yielded no cover crop at the A-State site in the 2016 season. Organic matter and active carbon were significantly influenced by tillage treatments. Physical and biological properties were significantly increased with cover crops compared with no …


Seed Dormancy-Breaking In A Cold Desert Shrub In Relation To Sand Temperature And Moisture, Huiliang Liu, Buhailiqiemu Abudureheman, Lingwei Zhang, Jerry M. Baskin, Carol C. Baskin, Daoyuan Zhang Jan 2017

Seed Dormancy-Breaking In A Cold Desert Shrub In Relation To Sand Temperature And Moisture, Huiliang Liu, Buhailiqiemu Abudureheman, Lingwei Zhang, Jerry M. Baskin, Carol C. Baskin, Daoyuan Zhang

Biology Faculty Publications

Seasonal periodicity of seed germination and its relationship to seasonal changes in temperature and soil moisture have been well studied in seeds of species with physiological dormancy. However, relatively little information is available on the role of these environmental factors in controlling germination of seeds with physical dormancy (PY). Our primary aim was to determine if seeds of the cold desert sand dune semi-shrub Eremosparton songoricum exhibits seasonal periodicity of seed germination and the relationship between seed dormancy break and soil temperature and moisture. In the laboratory, seeds incubated on dry, wet, wet-dry and dry-wet sand were exposed to a …


Diet Composition Of Age-0 Fishes In Created Habitats Of The Lower Missouri River, Trevor A. Starks, James M. Long Jan 2017

Diet Composition Of Age-0 Fishes In Created Habitats Of The Lower Missouri River, Trevor A. Starks, James M. Long

United States Geological Survey: Staff Publications

Channelization of the Missouri River has greatly reduced the availability of shallow water habitats used by many larval and juvenile fishes and contributed to imperilment of floodplain-dependent biota. Creation of small side channels, or chutes, is being used to restore shallow water habitat and reverse negative environmental effects associated with channelization. In the summer of 2012, the U.S. Army Corps of Engineers collected early life stages of fishes from constructed chutes and nearby unrestored shallow habitats at six sites on the Missouri River between Rulo, Nebraska and St. Louis, Missouri. We compared the diets of two abundant species of fishes …


Applying Population And Community Ecology Theory To Advance Understanding Of Belowground Biogeochemistry, Robert W. Buchkowski, Mark A. Bradford, A. Stuart Grandy, Oswald J. Schmitz, William R. Wieder Jan 2017

Applying Population And Community Ecology Theory To Advance Understanding Of Belowground Biogeochemistry, Robert W. Buchkowski, Mark A. Bradford, A. Stuart Grandy, Oswald J. Schmitz, William R. Wieder

Faculty Publications

Approaches to quantifying and predicting soil biogeochemical cycles mostly consider microbial biomass and community composition as products of the abiotic environment. Current numerical approaches then primarily emphasise the importance of microbe–environment interactions and physiology as controls on biogeochemical cycles. Decidedly less attention has been paid to understanding control exerted by community dynamics and biotic interactions. Yet a rich literature of theoretical and empirical contributions highlights the importance of considering how variation in microbial population ecology, especially biotic interactions, is related to variation in key biogeochemical processes like soil carbon formation. We demonstrate how a population and community ecology perspective can …