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Promoting Change In Common Tern (Sterna Hirundo) Nest Site Selection To Minimize Construction Related Disturbance., Peter C. Mcgowan, Jeffery D. Sullivan, Carl R. Callahan, William Schultz, Jennifer L. Wall, Diann J. Prosser

United States Geological Survey: Staff Publications

Due to the many challenges facing waterbird populations (Jia et al. 2018, Wetlands International 2018), it has become common practice to limit disturbance to breeding colonies whenever possible to maximize reproductive success. While this may require often unpopular management techniques including beach closures (Jorgensen et al. 2015, Mayo et al. 2015) and predator removal (Neuman et al. 2004, Stocking et al. 2017), such actions are sometimes necessary for the success of the colony. However, there are instances when eliminating disturbance is not possible and birds must be attracted to a new site. A common method for attracting waterbirds to a …

Oldowan Tool Behaviors Through Time On The Homa Peninsula, Kenya, Emma M. Finestone

Dissertations, Theses, and Capstone Projects

The adaptive significance of tool use to genus Homo is a central theme in human origins. However, what we know from the early Oldowan sites suggests that persistent technology may have begun as an opportunistic behavior with minimal investment, rather than a habitual and widespread adaptive revolution. This dissertation seeks to investigate investment in Oldowan tool production on the Homa Peninsula, Kenya, considering raw material selection, transport, and lithic production at two newly discovered Oldowan localities: Nyayanga (ca. 2.6 Ma) and Sare River (ca. 1.7 Ma).

The first section of this dissertation outlines a method that enables the comparison of …

Water Productivity In Meat And Milk Production In The Us From 1960 To 2016, Mesfin Mekonnen, C.M.U. Neale, Chittaranjan Ray, Galen E. Erickson, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

Global demand for livestock products is rising, resulting in a growing demand for feed and potentially burdening freshwater resources to produce this feed. To offset this increased pressure on water resources, the environmental performance of livestock sector should continue to improve. Over the last few decades, product output per animal and feedstuff yields in the US have improved, but before now it was unclear to what extent these improvements influenced the water productivity (WP) of the livestock products. In this research, we estimate changes in WP of animal products from 1960 to 2016. We consider feed conversion ratios (dry matter …

The Archaeology Of Mississippian Vulnerability And Resilience In The New Madrid Seismic Zone, Michelle Megan Rathgaber

Graduate Theses and Dissertations

This work examines the vulnerability and resilience of Mississippian people in the Central Mississippi Valley to the large-scale New Madrid seismic zone earthquakes of the late15th to early 16th century. This is done using the theory of eventful archaeology/anthropology to look at cultural materials both before and after an event (such as an earthquake and sand blows) to look for evidence of changes to the schema and resources on which a society relies. If changes are present, the event can be labeled as such, if there are no changes, it means that the society affected did not see the event …

Microbial Community, Functioning, And Its Relationship With Heavy Metals In An Urban Brownfield, Jay Prakash Singh

Theses, Dissertations and Culminating Projects

The ubiquity of urban brownfields presents a challenge for environmental managers for managing degraded ecosystems that are in close contact with human habitation. Presence of metal contaminants in brownfields further complicate the matters as it cannot be degraded and hence pose a high risk to human and environmental health, and well-being of the local community. However, previous studies indicate that management and restoration of brownfields are possible through the use of low input longer term and sustainable remediation approaches. These sustainable approaches include the use of plants, fungi, and bacteria to increase soil function and mitigate risks from the contaminants. …

Lipid Biomarkers Of Bering And Chukchi Sea Euphausiids And Their Application To Diet History, Rachel L. Pleuthner

OES Theses and Dissertations

In the eastern Bering Sea, Thysanoessa raschii are the most abundant krill species and a keystone trophic member that serve as both an important grazer and link to upper level consumers. In this system krill experience large annual variation in food resources, especially during ice advance and retreat; multiple lipid classes are used to temper the effects of those fluctuations, as well as to fuel reproduction and growth. Two shipboard feeding experiments that occurred during late spring and early summer of 2010, respectively, monitored the lipid retention in adult T. raschii and examined the fluctuation of specific lipid biomarkers under …

The Distribution And Biogeochemistry Of Subtropical Intertidal Microbial Mats, Bert D. Anderson

USF Tampa Graduate Theses and Dissertations

Microbial mats have played an important role in the carbon (C) and nutrient cycles since the Archean Eon and modern mats are important contributors to the biogeochemistry of intertidal wetlands. Microbial mats are flat assemblages of microbes that are currently found in many unvegetated habitats globally. Intertidal salt pans are a common habitat for microbial mats, however little is known about the distribution of microbial mats within the intertidal landscape. Understanding the spatial distribution of microbial mats is critical to developing quantitative estimates of the impacts of microbial mats on their ecosystems. We photographically measured the presence and density of …

Unexplored Diversity Of The Mesophotic Echinoderm Fauna Of The Easter Island Ecoregion, Ariadna Mecho, Erin E. Easton, Javier Sellanes, Matthias Gorny, Christopher Mah

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Easter Island ecoregion (EIE) is one of the most remote marine areas of the world and encompasses a vast and fragile ecosystem including oceanic islands and seamounts. In January 2014 and March 2016, a remotely operated vehicle was used to explore a subsurface peak off Easter Island (27.23°S, 109.48°W) and a seamount (26.92°S, 110.26°W), respectively located 10 km southwest and 98 km west of the island. More than 950 echinoderms were observed in the 5 h of video recorded during the seven dives conducted at depths between ~ 160 and 280 m. The communities of echinoderms observed at these …

Toward The Ultrasonic Sensing Of Organic Carbon In Seagrass-Bearing Sediments, Gabriel R. Venegas, Abdullah Rahman, Kevin M. Lee, Megan S. Ballard, Preston S. Wilson

School of Earth, Environmental, & Marine Sciences Faculty Publications

Ten percent of all organic carbon (Corg) absorbed by the ocean each year is stored in seagrass-bearing sediments. The preservation of these carbon stores is considered a vital method to mitigate climate change. Seagrass-bearing sediments have been correlated with sediment geophysical properties yet have not been related to sediment acoustic properties. For this purpose, sediment cores were collected from a Thalassia testudinum seagrass meadow in South Texas, USA, where geophysical, acoustical, and Corg properties were measured. It is hypothesized that when deposits of Corg adsorb onto mineral surfaces and are stored in pore spaces, compliant layers between grain contacts and …

Cave Temperature And Management Implications In Lehman Caves, Great Basin National Park, Usa, Stanka Šebela, Gretchen Baker, Barbara Luke

Civil and Environmental Engineering and Construction Faculty Research

Cave air temperature was measured at six locations in Lehman Caves (USA) for one year at hourly intervals. Lehman is a show cave in a national park, treasured for its geological and biological resources. The two monitoring locations that are off of the tour route and, also, relatively distant from the cave’s entrances displayed nearly constant air temperature during the year. The other four sites, along the tour route, show daily temperature variation as well as annual fluctuation. After visitation levels decreased in the autumn, cave temperatures lagged but eventually reached an equilibrium which demonstrates recovery in the quiet winter. …

Factors Influencing The Spatial Distribution Of Southern Rust In Corn, Justin Bailey

Graduate Theses and Dissertations

Southern rust caused by the fungus Puccinia polysora (Underwood) is the most economically important foliar disease in corn (Zea mays) (Linnaeus) (Cyperales: Poaceae)) for Arkansas. The objective of this work was to determine distribution of southern rust in corn and to determine factors that may control its distribution.

During the 2017 and 2018 season, seven corn fields in Arkansas were rated for southern rust. After disease confirmation, fields were marked with GPS sample point locations in a grid pattern across the entire field. Ratings for disease severity were taken below, at, and above the ear leaf at each point every …

Community Ecology And Population Dynamics Of The Nearshore Marine Fauna In The Middle Atlantic Bight (Usa), Juan Carlos Levesque

Earth & Environmental Sciences Dissertations - Archive

Natural resources are among the most valuable commodities on earth. Some natural resources (air, land, and water) are essential for human survival and many often constitute a large percentage of local, regional, and national economies, such as marine resources. Worldwide, marine resources have shaped culture, society, and local, regional, and global economies. Oceanic environmental conditions influence, shape, and control the geographical range, spatial distribution, abundance, and size composition of marine fauna. Thus, marine communities are vulnerable to major changes in the environmental conditions and disturbance (short and long-term), but the response and severity depends on various biological or ecological factors, …

Observations On The Magnetic Iron Oxide Content Of Particulate Matter In The Sahel, Kimberly Belle Tidd

Earth & Environmental Sciences Theses - Archive

Atmospheric dust influences many processes throughout the biosphere, hydrosphere, and atmosphere, most notably the climate, marine productivity, and human health. Recognizing the physicochemical characteristics of dust particulates will assist with monitoring the changes brought on by dust storms, as well as changes that may occur if dust subsides. Munsell soil color analysis was used to identify the degree of weathering at sample collection sites from the Sahel, a climate-sensitive region of North Africa. Scanning electron microscopy and energy dispersive x-ray spectroscopy were used to obtain the size, shape, and elemental makeup of individual magnetic metal particulates. Samples examined were collected …

Leveraging Environmental Research And Observation Networks To Advance Soil Carbon Science, Alejandro N. Flores

Geosciences Faculty Publications and Presentations

Soil organic matter (SOM) is a critical ecosystem variable regulated by interacting physical, chemical, and biological processes. Collaborative efforts to integrate perspectives, data, and models from interdisciplinary research and observation networks can significantly advance predictive understanding of SOM. We outline how integrating three networks—the Long‐Term Ecological Research with a focus on ecological dynamics, the Critical Zone Observatories with strengths in landscape/geologic context, and the National Ecological Observatory Network with standardized multiscale measurements—can advance SOM knowledge. This integration requires improved data dissemination and sharing, coordinated data collection activities, and enhanced collaboration between empiricists and modelers within and across networks.

Effects Of Elevated Temperature On Gonadal Functions, Cellular Apoptosis, And Oxidative Stress In Atlantic Sea Urchin (Arbacia Punctulata), Jackson B. Johnstone

Theses and Dissertations

Increasing surface sea water temperatures effect on growth, reproduction and development in marine organisms. Sea urchins are excellent indicator species and ideal model organisms to focus on. In this study, I tested the effect of higher temperatures on reproductive functions, heat shock protein (HSP, a chaperone protein produced by cells in response to heat stress) and nitrotyrosine protein (NTP, an indicator of reactive nitrogen species, RNS) expressions, cellular apoptosis, and ceolomic fluid (CF, a body fluid which regulates important physiological processes) conditions in Atlantic sea urchin at three different temperatures. Ten sea urchins were placed in each of six aquariums …

Effects Of Global Warming On Gonadal Functions, Cellular Apoptosis, And Oxidative Stress In The American Oyster, Sarah B. Nash

Theses and Dissertations

Global warming due to climate change is predicted to intensify the heat stress in marine and coastal organisms, affecting their development, growth and reproductive functions. In this study. I analyzed gonadal development, heat shock protein 70 (HSP70), nitrotyrosine protein (NTP), dinitrophenyl (DNP) expressions, cellular apoptosis, and coelomic fluid (CF) conditions in American oyster. Oysters were placed in six aquariums and exposed to control (24°C), medium (28°C), and high (32°C) temperatures for one week. Higher temperature significantly decreased the number of eggs and sperm. CF protein concentrations also declined compared to control. In contrast, CF pH and HSP70 expression in gonad …

The Evaluation Of Low-Use-Rate Zinc Fertilization Strategies On Seedling Canopy Coverage, Zn Concentration, Biomass, And Grain Yield, Maxwell David Coffin

Graduate Theses and Dissertations

Zinc (Zn) is the most common micronutrient deficiency in flooded rice (Oryza sativa L.). Some new Zn fertilization methods have been advertised, but have limited research supporting their efficacy. This study mainly compared the effect of Zn-seed treatment rate in combination with other low-use-rate Zn-fertilization methods to the standard of 11 kg Zn ha-1 as ZnSO4 on rice early-season canopy cover, tissue-Zn concentration, and grain yield. A secondary objective evaluated an alternative method (to seed treatment with ZnO) of enhancing seed-Zn concentration using post-heading foliar-Zn application on seedling tissue-Zn concentration and grain yield. For the main objective, rice seed was …

Responses Of Soil Carbon Sequestration To Climate-Smart Agriculture Practices: A Meta-Analysis, Xiongxiong Bai, Yawen Huang, Wei Ren, Mark Coyne, Pierre-Andre Jacinthe, Bo Tao, Dafeng Hui, Jian Yang, Chris Matocha

Biology Faculty Research

Climate-smart agriculture (CSA) management practices (e.g., conservation tillage, cover crops, and biochar applications) have been widely adopted to enhance soil organic carbon (SOC) sequestration and to reduce greenhouse gas emissions while ensuring crop productivity. However, current measurements regarding the influences of CSA management practices on SOC sequestration diverge widely, making it difficult to derive conclusions about individual and combined CSA management effects and bringing large uncertainties in quantifying the potential of the agricultural sector to mitigate climate change. We conducted a meta-analysis of 3,049 paired measurements from 417 peer-reviewed articles to examine the effects of three common CSA management practices …

Relative Salt Tolerance Of Seven Japanese Spirea Cultivars, Yuxiang Wang, Liqin Li, Youping Sun, Xin Dai

Plants, Soils, and Climate Faculty Publications

Spirea (Spiraea sp.) plants are commonly used in landscapes in Utah and the intermountain western United States. The relative salt tolerance of seven japanese spirea (Spiraea japonica) cultivars (Galen, Minspi, NCSX1, NCSX2, SMNSJMFP, Tracy, and Yan) were evaluated in a greenhouse. Plants were irrigated with a nutrient solution with an electrical conductivity (EC) of 1.2 dSmL1 (control) or saline solutions with an EC of 3.0 or 6.0 dSmL1 once per week for 8 weeks. At 8 weeks after the initiation of treatment, all japanese spirea cultivars irrigated with saline solution with an EC of 3.0 dSmL1 still exhibited good or …

Regenerative Grazing And The Benefits Of Livestock On Soils In Northern New South Wales, Raymond Mooney

Independent Study Project (ISP) Collection

Conventional cattle grazing has received criticism for environmental degradation in the past. Regenerative grazing and the principles of regenerative agriculture show encouraging signs that proper livestock management and planned grazing can reverse degradation and mitigate climate change. An emphasis on soil health and increasing soil carbon and organic matter levels reveals positive feedback for environmental health, the economic security of farmers, and nutritional health of consumers.

In this study I looked to investigate the benefits of regenerative agriculture, reasons why it is being practiced, and the extent it is practiced within the grazing in comparison to traditional methods within Northern …

Droughtscape, Spring 2019, Cory Matteson

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

From the Director

Wet and cool conditions bring drought relief to the West

Notable numbers from Q1

Drought impact summary, 1st quarter 2019

New research examines drought effects on state recreation areas

At Ethiopian space science workshop, NDMC climatologist sees promise in preparing for drought

U.S.- affiliated Pacific Islands now part of U.S. Drought Monitor

Water conservation tips for drought, flood and other disasters

Upcoming events

Learning From The Soil's Memory: Tailoring Of Fertilizer Application Based On Past Manure Applications Increases Fertilizer Use Efficiency And Crop Productivity On Kenyan Smallholder Farms, Samuel Njoroge, Antonius G.T. Schut, Ken E. Giller, Shamie Zingore

All Peer-Reviewed Publications

The large uncertainty in yield response to fertilizer application within smallholder cropping systems in sub-Saharan Africa (SSA) limits efforts aimed at intensifying crop production based on increased fertilizer application. We assessed the key field-scale cause of variability in maize (Zea mays) grain yield response to fertilizer nitrogen (N), phosphorus (P) and potassium (K) in the Sidindi area of Western Kenya based on past manure application, distance from the homestead, and clay and silt contents. We used data from nutrient omission trials conducted on 23 farms over seven consecutive cropping seasons covering the period 2013–2016, without changing treatments or plot location. …

Defining, Measuring, And Applying Soil Quality: An Unresolved Debate, Salvador Ramirez Ii

Doctor of Plant Health Program: Dissertations and Student Research

Paradigm shifts occur periodically in the sciences. Proposed paradigm shifts offer opportunities to reexamine extant paradigms and evaluate new ones. Soil science experienced a controversy resembling a proposed paradigm shift in the late 1990s and early 2000s when it grappled with the idea of soil quality (SQ). The most contentious points in the SQ debates were (1) the word “quality” itself and designing a functional definition, (2) identifying appropriate soil quality indicators, (3) the integration of soil quality indicators, and (4) the interpretation of soil quality indicators. The latter three disagreements were rooted in the established, fundamental, soil science paradigm. …

Endolithic Microbial Carbon Cycling In East Antarctica, Natalie Tyler

Theses and Dissertations

Microbes adapt to inhospitable conditions by colonizing niches that protect them from severe environmental conditions, making them model organisms in the search for life on other planets. Endoliths are globally ubiquitous microbes that colonize structural cavities within rocks, which protect them from environmental stressors while maintaining access to nutrition and light sources. Despite harsh katabatic winds, extreme temperature fluctuations, harmful UV radiation and exposure to desiccation, endolithic communities have been observed in Antarctica. Previous studies have found viable and abundant microbial biomass through microscopy and the addition of isotopic labels. However, due to the slow metabolic activity of these microbes, …

Assessing Variation In Us Soybean Seed Composition (Protein And Oil), Yared Assefa, Larry C. Purcell, Montse Salmeron, Seth Naeve, Shaun N. Casteel, Péter Kovács, Sotirios Archontoulis, Mark Licht, Fred Below, Herman Kandel, Laura E. Lindsey, John Gaska, Shawn Conley, Charles Shapiro, John M. Orlowski, Bobby R. Golden, Gurpreet Kaur, Maninderpal Singh, Kurt Thelen, Randall Laurenz, Dan Davidson, Ignacio A. Ciampitti

Plant and Soil Sciences Faculty Publications

Soybean [Glycine max (L.) Merr.] seed composition and yield are a function of genetics (G), environment (E), and management (M) practices, but contribution of each factor to seed composition and yield are not well understood. The goal of this synthesis-analysis was to identify the main effects of G, E, and M factors on seed composition (protein and oil concentration) and yield. The entire dataset (13,574 data points) consisted of 21 studies conducted across the United States (US) between 2002 and 2017 with varying treatments and all reporting seed yield and composition. Environment (E), defined as site-year, was the dominant …

Seasonal Origins Of Soil Water Used By Trees, Scott T. Allen, James W. Kirchner, Sabine Braun, Rolf T. W. Siegwolf, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Rain recharges soil water storages and either percolates downward into aquifers and streams or is returned to the atmosphere through evapotranspiration. Although it is commonly assumed that summer rainfall recharges plant-available water during the growing season, the seasonal origins of water used by plants have not been systematically explored. We characterize the seasonal origins of waters in soils and trees by comparing their midsummer isotopic signatures (δ2H) to seasonal isotopic cycles in precipitation, using a new seasonal origin index. Across 182 Swiss forest sites, xylem water isotopic signatures show that summer rain was not the predominant water source …

Wayne E. Sabbe Arkansas Soil Fertility Studies 2018, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.

Limits To The World’S Green Water Resources For Food, Feed, Fiber, Timber, And Bioenergy, Joep F. Schyns, Arjen Y. Hoekstra, Martijn J. Booij, Rick J. Hogeboom, Mesfin Mekonnen

Daugherty Water for Food Global Institute: Faculty Publications

Green water––rainfall over land that eventually flows back to the atmosphere as evapotranspiration––is the main source of water to produce food, feed, fiber, timber, and bioenergy. To understand how freshwater scarcity constrains production of these goods, we need to consider limits to the green water footprint (WFg), the green water flow allocated to human society. However, research traditionally focuses on scarcity of blue water––groundwater and surface water. Here we expand the debate on water scarcity by considering green water scarcity (WSg). At 5 × 5 arc-minute spatial resolution, we quantify WFg and the maximum sustainable level to this footprint (WFg,m), …

How Good Is Our Kentucky Haylage? A Summary Of 2017-18 Farm Results, Jimmy C. Henning, Jeff Lehmkuhler, Levi Berg, April Wilhoit, Corinne Belton, Tommy R. Yankey

Kentucky Alfalfa and Stored Forage Conference

The ability to harvest moist forage as hay gives Kentucky producers many advantages, including timely harvest, higher forage quality, and less weathering loss over hay systems. The baleage system allows producers to utilize commonly available forage equipment (mowers, rakes, balers) rather than requiring choppers and silo structures or bags. Making high quality baleage requires timely access to bale wrappers.

Genetic Loci Associated With Salt Tolerance In Advanced Breeding Populations Of Tetraploid Alfalfa Using Genome-Wide Association Studies, Xiang-Ping Liu, Charles Hawkins, Michael D. Peel, Long-Xi Yu

Plants, Soils, and Climate Faculty Publications

Many agricultural lands in the western United States consist of soil with high concentrations of salt, which is detrimental to alfalfa (Medicago sativa L.) growth and production, especially in the region where water resource is limited. Developing alfalfa varieties with salt tolerance is imperative for sustainable production under increasing soil salinity. In the present study, we used advanced alfalfa breeding populations and evaluated five traits related to salt tolerance including biomass dry weight (DW) and fresh weight (FW), plant height (PH), leaf relative water content (RWC), and stomatal conductance (SC) under control and salt stress. Stress susceptibility index (SSI) …