Digital Commons Network^™

Response To Drought Of White Clover Lines Selected For Different Stolon Morphologies, H D. Karsten, J R. Caradus, D R. Woodfield

IGC Proceedings (1977-2023)

White clover (Trifolium repens L.) lines were selected from within large and small-leaved cultivars of Grasslands Kopu and Grasslands Tahora, respectively, for long or short internodes, and for high or low branching frequency from plants grown in sun and shade (50% full sunlight). Lines were compared for drought tolerance in a perennial ryegrass (Lolium perenne L.) sward in boxes. Prior to imposing drought branching frequency selections did not differ in branching frequency, although the low branching frequency selection had a higher percentage of rooted nodes. After an imposed drought treatment sun-selected lines grew better than shade-selected lines relative …

Kentucky Bluegrass Floral Induction And Cultivar Response To Mechanical Removal Of Harvest Residue, G A. Murray, J B. Swensen

IGC Proceedings (1977-2023)

Open-field burning of post-harvest residue from Kentucky bluegrass (Poa pratensis L.) seed fields is being phased out in Washington, USA and may be banned in Idaho. Burning encourages early fall regrowth and timely completion of fall floral induction. Cultivars have different floral induction requirements and respond differently to mechanical residue removal. Our objective was to determine if length of fall floral induction requirement was related to seed yield when post-harvest residue was removed by crewcut vacuum sweeping. Floral induction requirements were not related to first-or second-year seed yields. Third-year seed yield of cultivars with long floral induction requirements declined …

The Influence Of Intensity Of Tree Thinning On The Redistribution Of Soil Water In Southern African Mopani Veld, G N. Smit, N F.G. Rethman, A Moore, A Le Roux, J S. Swart

IGC Proceedings (1977-2023)

The investigation was conducted on a densely wooded area in the Mopani veld of South Africa. Six plots were subjected to different intensities of tree thinning, ranging from a totally cleared plot (0 %) to plots thinned to the equivalent of 10%, 20%, 35%, 50% and 75% of the leaf biomass of a control plot (100%). Soil water measurements were taken at six different depths to a depth of 825 mm. The infiltration of rain water and redistribution within the soil profile exhibited marked differences between experimental plots. The soil water was predominantly held at a very shallow depth ( …

Relationship Of Visual And Quantitative Methods Of Grass Sward Development, R B. Mitchell, L E. Moser, K J. Moore

IGC Proceedings (1977-2023)

The objective of this study was to determine the relationship between visual and quantitative estimates of the morphological development of perennial grass swards. Pure stands of intermediate wheatgrass [Thinopyrum intermedium (Host) Barkw. & D.R. Dewey] and switchgrass (Panicum virgatum L.) were hand-clipped to ground level at 2-wk intervals in 1991 at Mead, NE, morphologically classified as mean stage count (MSC), and visually estimated for sward development. Visual estimations of sward development for both species were representative of quantitative measurements during vegetative growth. However, as sward development advanced to the elongation and heading stages, visual methods over-estimated the population …

Morphological Development Rates Of Perennial Forage Grasses, R B. Mitchell, L E. Moser, K J. Moore, D D. Redfearn

IGC Proceedings (1977-2023)

The objective of this study was to determine the rate of change in the morphological development of switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerardii Vitman). Pure stands of each species were sampled at weekly intervals in 1990 and 1991 at Mead, NE, and morphologically classified as mean stage count (MSC) and mean stage weight (MSW). Linear day of the year equations accounted for 94% of the variation in switchgrass MSC and MSW. Switchgrass MSC and MSW increased at an average rate of 0.0204 and 0.0234 units per day, respectively. Linear day of the year equations accounted …

Fertilizer Nitrogen And Morphogenetic Response In Avena Sativa And Lolium Multiflorum, F Lattanzi, M A. Marino, A Mazzanti

IGC Proceedings (1977-2023)

A field experiment was carried out at the EEA Balcarce, INTA, Argentina (37° 45’LS, 58° 18’LW) to determine whether Leaf Appearance Rate (LAR) was affected by N fertilization in Italian ryegrass (Lolium multiflorum Lam.) and forage oats (Avena sativa). N treatments (0, 50, 100, 150, 200 and 250 kg N ha-1) were applied in winter 1995, after a defoliation. Subsequently, number of leaves per tiller was determined on 45 labelled tillers in each treatment twice a week. LAR was calculated as the slope of the linear regression of number of leaves on thermal time (air temperature, base …

Allocation Of Carbon-14 To Roots Of Different Ages In Perennial Ryegrass (Lolium Perenne L.), C Matthew, W D. Kemball

IGC Proceedings (1977-2023)

The objective of this study was to provide information on how current photosynthate allocated to the root system in perennial ryegrass (Lolium perenne L.) is distributed among individual roots at differing nodal positions. Mature single ryegrass tillers were transplanted in September 1993 to glass house pots and three months later four of the plants were supplied with 14CO2. Individual roots from these radioactively-labeled plants were identified according to their nodal position on the tiller axis and amount of radiocarbon in each root quantified for root tip segments and for the remainder of the root axis. Similar plants were destructively …

The Analysis Of Dynamic Interaction In Legume Binary Mixture Under Controlled Conditions Of Irrigation And Clipping, M S. Vrahnakis, B Noitsakis, Z Koukoura

IGC Proceedings (1977-2023)

The objective of this study was to analyse the type of interference that occurred between the annual legume species, purple clover (Trifolium purpureum L.) and narrow leaved crimson clover (Trifolium angustifolium Loisel. ), growing in mixed conditions under two different watering regimes and two different clipping treatments. A replacement series experiment was conducted in pots placed in the field. The above ground biomass (gr/plant) were measured. The recently proposed Inverse Linear Model was implied in order to analyse the competitive interaction between the above species. The results suggest that Tr. purpureum was the superior competitor to Tr. angustifolium …

Beach Processes Controlling Erosional Hotspots And Their Influences On Beach Nourishment Performances: A Case Study Along West-Central Florida Barrier Island Beaches, Sophia Gutierrez

USF Tampa Graduate Theses and Dissertations

This study examines the long-term performance of repeated beach nourishment over an approximately 35-year period at two barrier islands, Sand Key and Treasure Island along the west-central Florida coast, USA. Five cycles of beach nourishment on Sand Key and six on Treasure Island were conducted during the study period. Three erosional hotspots were identified along a combined 14-km stretch of the nourished beach. The processes that cause the erosional hotspot were examined through numerical modeling of nearshore wave and current fields.

The most recent three nourishments since 2006 were monitored systematically by this study. Beach profiles were surveyed bimonthly to …

Festival Of Research Abstracts, Spring 2024, College Of Science And Mathematics, Wright State University

Festival of Research

The collection of abstracts accepted for the Spring 2024 Festival of Research hosted by the Wright State University College of Science and Mathematics.

Paradox Lost: Wide Gape In The Ordovician Brachiopod Rafinesquina Explains How Unattached Filter-Feeding Strophomenoids Thrived On Muddy Substrates, Benjamin F. Dattilo, Rebecca L. Freeman, Kyle Hartshorn, David Peterman, Aaron Morse, David L. Meyer, Lindsay G. Dougan, James W. Hagadorn

Earth and Environmental Sciences Faculty Publications

Strophomenoid brachiopods had thin, concavo-convex shells, were ubiquitous colonizers of Palaeozoic muddy seafloors, and are hypothesized to have filter-fed in a concave-upward orientation. This orientation would elevate their line of commissure out of potentially lethal lophophore-clogging mud. The paradox is that epi- biont distributions on strophomenoids support a convex-upward life position, as do studies of strophome- noid stability and trace fossils formed by strophomenoid sediment-clearing. A premise of the concave-upward orientation hypothesis is a narrow gape, which causes narrow, high velocity inhalant currents, leaving strophomenoids vul- nerable to sediment entrainment. Herein we investigate the gape angle of Rafinesquina using serial …

Consumer Preferences For Wood-Pellet-Based Green Pricing Programs In The Eastern United States, Sydney Oluoch, Pankaj Lal, Andres Susaeta, Meghann Smith, Bernabas Wolde

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Co-firing wood pellets with coal is an attractive alternative energy generation method with economic, social, and environmental benefits for the US energy generation sector. One way to sustainably use wood pellets for co-firing is to create consumer-supported green pricing programs (GPPs). Our study surveyed residents of five states (Alabama, New Jersey, New York, Pennsylvania, and Virginia) to investigate preferences for the attributes of a hypothetical GPP. The study applied the Best Worst Choice method, which employs the Best Worst Scaling (BWS) and binary choice (BC) task. The BWS analysis showed that residents of all five states most value the flexibility …

Joint Environmental And Social Benefits From Diversified Agriculture, Laura Vang Rasmussen, Ingo Grass

Earth and Environmental Sciences Faculty Publications

Agricultural simplification continues to expand at the expense of more diverse forms of agriculture. This simplification, for example, in the form of intensively managed monocultures, poses a risk to keeping the world within safe and just Earth system boundaries. Here, we estimated how agricultural diversification simultaneously affects social and environmental outcomes. Drawing from 24 studies in 11 countries across 2655 farms, we show how five diversification strategies focusing on livestock, crops, soils, noncrop plantings, and water conservation benefit social (e.g., human well-being, yields, and food security) and environmental (e.g., biodiversity, ecosystem services, and reduced environmental externalities) outcomes. We found that …

Unearthing The Past: A Comprehensive Study Of Natural And Anthropogenic Changes At An Archaeological Site Through Hydrogeologic Connectivity Utilizing Gis, Mehlich Ii Phosphorus Extractant, And Ph, Dana L. F. Herren

Theses

This thesis aims to thoroughly analyze the Mehlich II Phosphorus Extractant and pH levels at the Bains Gap Village Site in Anniston, AL., while examining the impact of various environmental factors and human activities on them. Phosphorus is often used in archaeology as an indicator of human activity. Soil core samples were collected to analyze anomalies in phosphorus levels.

To establish any relationships, phosphorus and pH levels from soil cores were correlated with findings from past excavation units and features. The potential effects of hydrogeologic connectivity on soil phosphorus and pH levels were investigated. Geospatial technologies were used to manage …

What Soil Is Worth: A Cost-Benefit Framework Analysis Of Syntropic Farming, Aubrey Kettley

Independent Study Project (ISP) Collection

Syntropic farming, a type of regenerative agriculture, models its farming system after a forest. This type of farming prioritizes soil health while also providing a varied yield of crops. Because it is a fairly new system globally, little research has been done on the economic impacts of syntropic farming, and therefore the feasibility of scaling up regenerative systems like this. This study aims to analyze the economic feasibility of this system through a literature review and a cost-benefit analysis framework. The results highlight the applicability, environmental advantage and economic feasibility of the system. Based on the presented framework, the short …

Impacts Of Gas Flaring On Soil Quality In The Ecuadorian Amazon: Measuring Gas Flare Effects On Soils At Comparative Distances In Loma Del Tigre, Orellana, Francesca Lopresti

Independent Study Project (ISP) Collection

Gas flaring, the process of burning off the natural gas excreted during petroleum extraction, has recently been the source of public outcry, citing degraded public and environmental health caused by constant flaring near populated centers. While extensive research has been done on the environmental and health impacts of gas flaring, regionally specific research to the Ecuadorian Amazon is lacking. It is crucial that updated research in this region is produced to inform regulations that have the potential to minimize the physical, environmental, and economic impact of the petroleum industry on nearby, under-resourced, and marginalized communities. While air quality surrounding gas …

Beavers, Hydrology, And Wapato: A Baseline For Monitoring Franz Lake National Wildlife Refuge, Justine Casebolt

Environmental Science and Management Professional Master's Project Reports

Located in the lower Columbia River floodplain, Franz Lake National Wildlife Refuge is a unique landscape with a complex land use history. For thousands of years, Indigenous tribes lived on this land. In the early 1990s, U.S. Fish and Wildlife Service acquired the land, after it was identified as a mitigation site following the construction of the Bonneville Lock and Dam. Franz Lake Refuge was once known for its prevalent Wapato (Sagittaria latifolia) population, an emergent plant with edible tubers and an important food source for Indigenous people. With specific growth requirements and hydrologic conditions for germination and …

Kicking Up Dust On Utah's Off-Road Vehicle Trails: Pi-Swerl Assessment Of Anthropogenic Dust Emissions, Wyatt A. Wiebelhaus

Honors Thesis

Upward trends in the use of off-highway vehicles (OHV) and the creation of new OHV trails facilitate an increase in soil disturbance and dust emissions in Utah. Anthropogenic destruction of soil crusts and the removal of vegetation by OHVs exposes soil and destroys soil structure, making the soil easier to erode by the wind. We used the PI-SWERL (Portable In Situ Wind Erosion Laboratory) to measure dust concentrations of disturbed and undisturbed soil. We tested soils at several popular OHV areas with landforms composed of sand dunes, playas, and Lake Bonneville sediments. Soil crust strength, grain size, and salinity were …

Demographic Consequences Of Off-River Nesting For Piping Plover (Charadrius Melodus) And Interior Least Tern (Sternula Antillarum Athalassos) In The Lower Platte River System, Nebraska, Elsa M. Forsberg

School of Natural Resources: Dissertations, Theses, and Student Research

Piping plovers (Charadrius melodus; hereafter, plovers) and interior least terns (Sternula antillarum athalassos; hereafter, terns) are two avian species that nest along the Lower Platte River system (LPRS) in Nebraska. In the LPRS, river sandbars provide natural nesting habitat, but off-river sites provide substantial nesting habitat especially when sandbar habitat is scarce. Although presumed to be important for the persistence of plovers and terns, off-river habitat is not self-sustaining and predicted to decline. Understanding the vital rates of plovers and terns in the LPRS will inform the role of off- river sites in the future conservation …

The Effect Of Sample Grinding On Color-Based Predictions Of Soil Organic Carbon, Mason Rutgers

Honors Program: Senior Projects (Public)

Measurements of soil color are widely accessible and can be used as indirect measures of soil organic carbon (SOC). Sensor-based soil color measurements, frequently used in quantitative studies to predict SOC, often use ground and sieved soil samples for color analysis. However, it is unknown whether the extra steps of drying, crushing, and sieving a sample improve the quantitative relationship between color and SOC. This study was conducted to evaluate color-based predictions of SOC using intact, sieved (<2 mm), and fine-ground soil samples from northwest Oklahoma. Moist soil color was measured using Munsell color charts (MCCs) and a Nix Mini 3™ portable color sensor (PCS). The color of the soil samples was measured before processing, after crushing to pass through a 2-mm sieve, and after mechanical grinding to less than 0.25-mm. Using Munsell value (from the MCC) and CIEL* (from the PCS) as predictor variables, regression analyses were conducted to develop SOC predictive functions for each physical state. The resulting coefficients of determination (R2) and root mean squared errors (RMSE) were used to assess model fits for predicting SOC. Model contrasts were calculated to evaluate significant differences between each predictive model. All models exhibited strong relationships (0.56 < R2 < 0.70, 0.20 < RMSE < 0.25) between soil lightness and predicted SOC. Models built using aggregated samples measured with both MCCs (R2= 0.70, RMSE= 0.20) and the PCS (R2= 0.69, RMSE= 0.21) produced the best results. Models built using intact samples measured using the PCS did perform significantly better on samples dark in color (CIEL* < 30). These results suggest that grinding soil samples does not improve color-based predictions of SOC using MCCs and the PCS.

Impact Of Climate Change On Carbon And Nitrogen Balance In Zostera Marina L. (Eelgrass), Malee Jinuntuya

OES Theses and Dissertations

Seagrasses face vulnerability to both global stressors like Ocean Acidification (OA) and climate warming compounded by local stressors such as eutrophication that reduces light availability, leading to a complex dynamic of positive and negative effect on their growth and survival. Increased dissolved aqueous CO₂ (CO_2(aq)) benefits seagrasses by enhancing photosynthetic and growth rates, but it may increase nutrient demand, potentially depleting nutrient supply, especially in oligotrophic environments.

In this study, the long-term impact of CO₂ on Zostera marina L. (eelgrass) were investigated across a gradient of CO_2(aq) concentrations (55 – 2200 µM CO_{2(aq)) …}

Hydrologic Impact Index For The Pinhoti Hiking Trail, Allie Field

Theses

Author note: The author of this thesis is also published under the name Allie Bobo.

This study aimed to identify flood-prone areas along the Pinhoti Trail and Chinnabee Silent Trail in the Talladega National Forest. Using the Hydrology Flood Index layer that was created using several essential data layers, the research aimed to provide campers, hikers, nature enthusiasts, and trail maintenance teams with information about areas at a higher risk of flash flooding. The Hydrology Flood Index layer rates the risk of flooding on a scale of 1 to 4, with level 1 indicating a low risk of flooding and …

The Role Of Geomorphological Context In Vegetative Succession Within The Breiðamerkurjökull Glacial Foreland, Lucas Nerbonne

Independent Study Project (ISP) Collection

As glaciers retreat worldwide at an accelerating pace, understanding primary succession in these newly exposed landscapes becomes increasingly critical. This study examines the initial vegetative colonization patterns in glacial forelands, focusing on the influence of geomorphological formations of resulting plant communities. By analyzing vegetative communities in glaciofluvial and push moraine deposits, this study highlights how the more varied, channelized morphologies of fluvial deposits create potential microclimates better conducive to heterogenous plant colonization than the homogenous terrain of the nearby push moraine. Vegetative coverage, sediment size, and species abundance was collected at 480 sites across 6 different historical glacial extents across …

Remote, Rugged Field Scenarios For Archaeology And The Field Sciences: Object Avoidance And 3d Flight Planning With Suas Photogrammetry, Carla Klehm, Malcolm D. Williamson, Leland C. Bement, Brandi Bethke

Center for Advanced Spatial Technologies Publications and Presentations

Advances built into recent sUASs (drones) offer a compelling possibility for field-based data collection in logistically challenging and GPS-denied environments. sUASs-based photogrammetry generates 3D models of features and landscapes, used extensively in archaeology as well as other field sciences. Until recently, navigation has been limited by the expertise of the pilot, as objects, like trees, and vertical or complex environments, such as cliffs, create significant risks to successful documentation. This article assesses sUASs’ capability for autonomous obstacle avoidance and 3D flight planning using data collection scenarios carried out in Black Mesa, Oklahoma. Imagery processed using commercial software confirmed that the …

The Impacts Of Nature-Based Sediment Restoration Practices On Coastal Wetland Soil Biogeochemistry, Jacob Z. Cheng

LSU Master's Theses

Coastal marshes provide many valuable ecosystem services. However, these wetlands are threatened worldwide, being subject to sea level rise, sediment starvation, subsidence, coastal edge erosion, etc. Many efforts are being made to counteract this wetland loss and preserve the ecosystem services. Two such methods are sediment diversion and the thin layer placement (TLP) of dredged sediment.

Sediment diversion involves reconnecting the main channel of a river body to disconnected wetlands, supplying much needed soil-building materials. However, this method affects the salinity of the waters, introducing large amounts of freshwater into the system. Salinity changes can affect marsh biogeochemistry. Most ecological …

Favorable Factors In Methane Production From Residual Coal Post-Biohydrogen Generation, Xia Daping, Liao Jiajia, Chen Zhenhong, Chen Xi, Guo Hongyu, Huang Dan

Coal Geology & Exploration

Determining favorable factors in methane production from residual coal post-biohydrogen production holds great theoretical and practical significance for improving the efficiency of methane production in the second stage of coal-based poly-generation. This study focuses on residual coal after hydrogen generation through anaerobic fermentation. Using coal samples from the Baiyinhua open-pit mine in Inner Mongolia as fermentation substrates, this study explored the dynamic trends of both the methane production and structure of the residual coal under different conditions by altering the aeration conditions and hydraulic retention time (HRT). Key findings are as follows: (1) Among the experiment groups with different atmosphere …

Leveraging Systems Thinking For Global Environmental Health, Martha M. Mcalister

USF Tampa Graduate Theses and Dissertations

Environmental health inequities such as household air pollution, inadequate water, sanitation, and hygiene, and chemical pollution persist globally and have myriad consequences on individual and societal well-being. Unfortunately, while billions of dollars and countless hours of research have been applied towards addressing these issues in development, humanitarian, and environmental justice contexts, attempts to reduce the environmental burden of disease can seem successful at first, but then backslide to pre-intervention conditions (or worse). This is indicative of policy resistance, a tendency of complex systems that makes it very difficult to enact change if the “rules” of the system are misunderstood. There …

Silvopastoral Agroforestry In Upland And Lowland Uk Grassland: Tree Growth And Animal Performance, W R. Eason, R Lavender, R O. Clements, C Duller, E Gill, M Hislop

IGC Proceedings (1977-2023)

Trees, individually protected from herbivore damage using plastic shelters, were planted at two densities (100 and 400 stems/ha) into sheepgrazed pasture in upland and lowland UK grassland sites in 1988. Tree and animal performance were compared with conventional forestry (no sheep) and pasture (no tree) systems. Effects on tree growth and survival are highly species and site dependent although some treatment effects did emerge. Tree shelters encouraged rapid early height growth compared to forestry controls although in some cases tree form was also adversely affected. Generally tree performance within agroforestry treatments was better at the higher planting density. Eight years …

Use Of Annual Self-Reseeding Legumes In An Oak Forest In Central Italy, P Talamucci, G Argenti, A Pardini, S Piemontese, N Stagliano

IGC Proceedings (1977-2023)

A trial has been carried out for three years in an oak coppice geometrically thinned out of Mediterranean Central Italy, about the functioning of a pastoral system made by four different resources: native pasture, subterranean clover (Trifolium brachycalycinum Katzn. et Morley) in pure stand, strips thinned out and firebreaks improved with oversown subclover, all grazed by sheep. Subclover increased the forage yield and improved the palatabilty of the pasture and the regularity of grazing; the higher biomass intake by animals reduced the quantity of dried biomass in summer and contributed to keep low either fire hazards or flame diffusion …

The Effects Of Shelterbelts On Adjacent Pastures And Soils In A Temperate Climate, A G. Gillingham, M F. Hawke

IGC Proceedings (1977-2023)

Two trials were conducted to differentiate the direct (exposure) from the indirect (modified soil fertility due to nutrient transfer by grazing animals) effects of farm shelterbelts on associated pasture growth.Soil from close to “unmanaged”shelterbelts with dense shelter to ground level had relatively high potassium (K) levels and, in a glasshouse situation, provided more pasture growth than soil from further distances, or from adjacent to “managed” shelterbelts. Pasture grown in boxes of a common soil implanted at increasing distances from a shelterbelt also produced highest growth rates close to shelter. These results generally explain the pattern of resident pasture growth, except …