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Rice Biomass Response To Various Phosphorus Fertilizers In A Phosphorus-Deficient Soil Under Simulated Furrow-Irrigation, Jonathan B. Brye 2024 University of Arkansas, Fayetteville

Rice Biomass Response To Various Phosphorus Fertilizers In A Phosphorus-Deficient Soil Under Simulated Furrow-Irrigation, Jonathan B. Brye

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Wastewater-recovered phosphorus (P), in the form of the mineral struvite (MgNH4PO4⋅6H2O), may provide a sustainable alternative to rapidly decreasing rock phosphate reserves. Struvite can be generated via chemical and/or electrochemical precipitation methods, potentially reducing the amount of P runoff to aquatic ecosystems. The objective of this greenhouse tub study was to evaluate the effects of chemically- and electrochemically precipitated struvite (CPST and ECST, respectively) on above- and belowground plant response in a hybrid rice cultivar (Gemini 214, RiceTec) grown using furrow-irrigation compared to other common fertilizer-P sources [i.e., triple super phosphate (TSP) and diammonium phosphate (DAP)] in a P-deficient silt …


Constraints On Near-Ridge Magmatism Using 40Ar/39Ar Geochronology Of Enriched Morb From The 8°20' N Seamount Chain, Molly K. Anderson, Michael R. Perfit, Leah E. Morgan, Daniel J. Fornari, Michael Cosca, V. Dorsey Wanless 2023 University of Florida

Constraints On Near-Ridge Magmatism Using 40Ar/39Ar Geochronology Of Enriched Morb From The 8°20' N Seamount Chain, Molly K. Anderson, Michael R. Perfit, Leah E. Morgan, Daniel J. Fornari, Michael Cosca, V. Dorsey Wanless

Geosciences Faculty Publications and Presentations

Our understanding of the spatial-temporal-compositional relationships between off-axis magmatism and mid-ocean ridge spreading centers is limited. Determining the 40Ar/39Ar ages of mid-ocean ridge basalt (MORB) lavas erupting near mid-ocean ridges (MOR) has been a challenge due to the characteristically low K2O contents in incompatible element-depleted normal MORB (NMORB). High-precision 40Ar/39Ar geochronology is used here to determine ages of young, basaltic lavas erupted along the 8°20' N seamount chain west of the East Pacific Rise (EPR) axis that have a range of incompatible element enrichments (EMORB) suitable for 40Ar/39Ar geochronology …


Is Macroporosity Controlled By Complexed Clay And Soil Organic Carbon?, Alejandro N. Flores 2023 Boise State University

Is Macroporosity Controlled By Complexed Clay And Soil Organic Carbon?, Alejandro N. Flores

Geosciences Faculty Publications and Presentations

Multi-scale evidence of rapid, climate-induced soil structural changes occurring at yearly to decadal timescales is mounting. As a result, it has become increasingly important to identify the properties and mechanisms controlling the development and maintenance of soil structure and associated macroporosity. This is especially relevant since macroporosity has disproportionate effects on saturated hydraulic conductivity (Ksat) which strongly influences water storage and flux, thus, affecting the water cycle. In this study, we use decision trees and piecewise linear regression to assess the influence of soil and climate properties on effective porosity (EP; a proxy of macroporosity) in both …


A Predictive Flood Model For Urban Karst Groundwater Systems, Trayson Lawler 2023 Western Kentucky University

A Predictive Flood Model For Urban Karst Groundwater Systems, Trayson Lawler

Masters Theses & Specialist Projects

Urban karst environments are often plagued by groundwater flooding, which occurs when water rises from the subsurface to the surface through the underlying caves and other karst features. The heterogeneity and interconnectedness of karst systems often makes them very unpredictable, especially during intense storm events; urbanization exacerbates the problem with the addition of many impervious surfaces. Residents in such areas are frequently disturbed and financially burdened by the effects of karst groundwater flooding. The Federal Emergency Management Agency (FEMA) offers limited protection to citizens living near flood-prone areas as they primarily focus on the areas near surface bodies of water. …


The Temporal Evolution Of Subduction Initiation In The Samail Ophiolite: High-Precision U–Pb Zircon Petrochronology Of The Metamorphic Sole, James L. Crowley, Mark Schmitz 2023 Boise State University

The Temporal Evolution Of Subduction Initiation In The Samail Ophiolite: High-Precision U–Pb Zircon Petrochronology Of The Metamorphic Sole, James L. Crowley, Mark Schmitz

Geosciences Faculty Publications and Presentations

High-precision dating of the metamorphic sole of ophiolites can provide insight into the tectonic evolution of ophiolites and subduction zone processes. To understand subduction initiation beneath a young, well-preserved and well-characterized ophiolite, we performed coupled zircon laser-ablation inductively coupled mass spectrometry trace element analyses and high-precision isotope dilution-thermal ionization mass spectrometry U–Pb dating on 25 samples from the metamorphic sole of the Samail ophiolite (Oman-United Arab Emirates). Zircon grains from amphibolite- to granulite-facies (0.8–1.3 GPa, ~700–900°C), garnet- and clinopyroxene-bearing amphibolite samples (n = 18) show systematic trends of decreasing heavy rare earth element slope (HREE; Yb/Dy) with decreasing Yb …


Change In Grassland Science: Implications For Training, Research And Grassland Societies, G. Lemaire, R. J. Wilkins, J. Hodgson 2023 Institut National de Recherche Agronomique, France

Change In Grassland Science: Implications For Training, Research And Grassland Societies, G. Lemaire, R. J. Wilkins, J. Hodgson

International Grassland Congress Proceedings

In most of the world the priority for production-oriented research has been succeeded by the need for grassland research to focus on systems which satisfy requirements relating to the stability and protection of land, water and atmospheric resources and to biodiversity, in addition to production efficiency. This dictates not only a new approach to research, but also new approaches for the organisation of research, the training and development of research scientists and the activities of Grassland Societies and associated organisations.


Citizen Scientists: Efforts By The Tri-Societies To Inject Science Into Us Policymaking, E. Bergfeld, K. Glasener 2023 American Society of Agronomy

Citizen Scientists: Efforts By The Tri-Societies To Inject Science Into Us Policymaking, E. Bergfeld, K. Glasener

International Grassland Congress Proceedings

The Tri-Societies (American Society of Agronomy, Crop Science Society of America and Soil Science Society of America), the largest life science professional societies in the United States (US) dedicated to the agronomic, crop and soil sciences, encompass approximately 18,000 members globally and include approximately 14,000 certified professionals who are a direct conduit to the farming communities across the US. The Tri-Societies' US-based federal science policy programmes have been active for decades. There is a Washington, DC-based Director of Science Policy, Congressional Science Fellows (CSF) and Science Policy Interns.


Predictive Modeling Of Cave Entrance Locations: Relationships Between Surface And Subsurface Morphology, William Blitch, Adia R. Sovie, Benjamin W. Tobin 2023 University of Kentucky, Lexington, USA

Predictive Modeling Of Cave Entrance Locations: Relationships Between Surface And Subsurface Morphology, William Blitch, Adia R. Sovie, Benjamin W. Tobin

International Journal of Speleology

Cave entrances directly connect the surface and subsurface geomorphology in karst landscapes. Understanding the spatial distribution of these features can help identify areas on the landscape that are critical to flow in the karst groundwater system. Sinkholes and springs are major locations of inflow and outflow from the groundwater system, respectively, however not all sinkholes and springs are equally connected to the main conduit system. Predicting where on the landscape zones of high connectivity exist is a challenge because cave entrances are difficult to detect and imperfectly documented. Wildlife research has a similar issue of understanding the complexities of where …


Comparing Drone2map Versus Pix4dmapper When Creating Orthophoto Mosaics Over Homogeneous Land Features, Victoria Williams, Daniel R. Unger, David Kulhavy, I-Kuai Hung, Yanli Zhang 2023 Stephen F. Austin State University

Comparing Drone2map Versus Pix4dmapper When Creating Orthophoto Mosaics Over Homogeneous Land Features, Victoria Williams, Daniel R. Unger, David Kulhavy, I-Kuai Hung, Yanli Zhang

International Journal of Geospatial and Environmental Research

This study evaluated two popular software packages currently used within the natural resources profession to create orthophoto mosaics: Drone2Map and Pix4Dmapper. Of particular concern was how effective these two software packages would perform in creating orthophoto mosaics over a city park in East Texas consisting of forest, open grass, and urban concrete surrounding a lake. Two drone flights over the city park were conducted. One flight was at 76 meters (250 feet) above ground with a single pass configuration. The other flight was at 122 meters (400 feet) above ground with a double pass configuration. Upon the completion of each …


Hydrology Data For Fern Cave, Alabama (2020-2022), Benjamin Tobin, Benjamin V. Miller, Matthew Niemiller, Andrea Erhardt 2023 University of Kentucky

Hydrology Data For Fern Cave, Alabama (2020-2022), Benjamin Tobin, Benjamin V. Miller, Matthew Niemiller, Andrea Erhardt

Research Data

Dataset includes water level from four sites within Fern Cave in Jackson County Alabama. Additionally, it includes chemistry of water, sediments and cave-adapted isopods.


Sustainability Of Permanent Grassland On A Low Moor Soil With Different N And K Nutrient Management, K. Orlovius, J. Pickert 2023 Agricultural Service of K+S KALI GmbH, Germany

Sustainability Of Permanent Grassland On A Low Moor Soil With Different N And K Nutrient Management, K. Orlovius, J. Pickert

International Grassland Congress Proceedings

After the reunification of Germany fertilisation with P and K was strongly reduced in the eastern states of Germany due to the poor financial situation of the farms. Particularly on sites with a low nutrient delivery capacity, such a nutrient management strategy implies the risk of decreasing soil fertility. On a low moor soil with permanent grassland a 4 - year trial with different N and K fertilisation was set up to study the development of dry matter production and K concentrations in the grass.


Holocene Rice Rats (Genus Oryzomys) From The Upper Mississippi River Drainage Basin, Hugh H. Genoways 2023 University of Nebraska - Lincoln

Holocene Rice Rats (Genus Oryzomys) From The Upper Mississippi River Drainage Basin, Hugh H. Genoways

Zea E-Books Collection

The expansion and collapse of the geographic range of the Texas rice rat (Oryzomys texensis) in the upper Mississippi River drainage basin at the end of the Holocene was a unique event in North American mammals. In a period of about 4000 years with a point of origin near the American Bottom in Illinois, these small rodents extended their geographic range in a straight-line distance of over 950 km to the west into Nebraska and the same distance to the east into Pennsylvania. Then in less than 400 years this range expansion collapsed back to a point where …


Thames River Subwatershed Soil, Sediment, Water Data, Justin B. Richardson, Mark J. Butler 2023 University of Massachusetts Amherst

Thames River Subwatershed Soil, Sediment, Water Data, Justin B. Richardson, Mark J. Butler

Data and Datasets

Trace element and nutrient data are for riparian soils, suspended sediments, eddy bottom sediments, and river water collected between 2019 and 2020 in the Thames River watershed of Connecticut, USA. Trace elements and nutrients were measured using EPA 3050B digestion method and analyzed by ICP-OES or ICP-MS.


Polygonal Faults In The Austin Chalk: Invariance Of Scale From Mud Cracks To Polygons With Implications Of Structural, Geomorphic And Isotopic Data On Polygonal Fault Geometry And Origin., Kun Shang 2023 Southern Methodist University

Polygonal Faults In The Austin Chalk: Invariance Of Scale From Mud Cracks To Polygons With Implications Of Structural, Geomorphic And Isotopic Data On Polygonal Fault Geometry And Origin., Kun Shang

Earth Sciences Theses and Dissertations

The Cretaceous Austin Chalk contains large numbers of fractures and normal faults whose orientations have been attributed to either regional stresses (e.g., the Balcones fault trend) or, by analogy with the mudrocks, to polygonal faulting resulting from compaction. In this study, we present geomorphic data, field study, and stable isotope data to support that the majority of these faults in North Texas are polygonal. Field-measured fault orientations suggest randomly distributed fault strikes, indicating a polygonal fault structure. Using geomorphologic data (topographic and DEM data) on stream orientations suggests that the polygonal fault patterns are best reflected in the headwater (1st …


Applications Of Environmental Dna (Edna) To Detect Subterranean And Aquatic Invasive Species: A Critical Review On The Challenges And Limitations Of Edna Metabarcoding, Sakib Tahmid Rishan, Richard J. Kline, Md Saydur Rahman 2023 The University of Texas Rio Grande Valley

Applications Of Environmental Dna (Edna) To Detect Subterranean And Aquatic Invasive Species: A Critical Review On The Challenges And Limitations Of Edna Metabarcoding, Sakib Tahmid Rishan, Richard J. Kline, Md Saydur Rahman

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

The world is struggling to solve a devastating biodiversity loss that not only affects the extinction of treasured species and irreplaceable genetic variation, but also jeopardizes the food production, health, and safety of people. All initiatives aimed to conserve biodiversity rely heavily on the monitoring of both species and populations to get accurate spatial patterns and overall population assessments. Conventional monitoring techniques, such as visual surveys and counting individuals, are problematic due to challenges in identifying cryptic species or immature life stages. Environmental DNA (eDNA) is a relatively new technology that has the potential to be a faster, non-invasive, and …


Effects Of Landslides On Terrestrial Carbon Stocks With A Coupled Geomorphic-Biologic Model: Southeast Alaska, United States, Adam M. Booth, Brian Buma, S. Nagorski 2023 Portland State University

Effects Of Landslides On Terrestrial Carbon Stocks With A Coupled Geomorphic-Biologic Model: Southeast Alaska, United States, Adam M. Booth, Brian Buma, S. Nagorski

Geology Faculty Publications and Presentations

Landslides influence the global carbon (C) cycle by facilitating transfer of terrestrial C in biomass and soils to offshore depocenters and redistributing C within the landscape, affecting the terrestrial C reservoir itself. How landslides affect terrestrial C stocks is rarely quantified, so we derive a model that couples stochastic landslides with terrestrial C dynamics, calibrated to temperate rainforests in southeast Alaska, United States. Modeled landslides episodically transfer C from scars to deposits and destroy living biomass. After a landslide, total C stocks on the scar recover, while those on the deposit either increase (in the case of living biomass) or …


Maintaining Grassland Plant Diversity While Controlling Woody Plant Encroachment, James Stubbendieck, Kay L. Kottas, S. J. Tunnell, S. J. Palazzolo 2023 University of Nebraska-Lincoln

Maintaining Grassland Plant Diversity While Controlling Woody Plant Encroachment, James Stubbendieck, Kay L. Kottas, S. J. Tunnell, S. J. Palazzolo

International Grassland Congress Proceedings

The tallgrass prairie region of the United States is a fragmented grassland ecosystem. Much of the 1 to 2% of the remaining prairie is being degraded by invading woody plants, which frequently results in a shift from grassland to woodland. Smooth sumac (Rhus glabra L.), a shrub native to the region, can rapidly increase in density and become dominant in the plant community. Prescribed fire alone is not a constraint to this resprouting species (Stubbendieck et al., 2003). Herbicides are useful tools for managing woody plants in grasslands, but the negative response of desirable plants to herbicides is …


Do Species And Functional Diversity Indices Reflect Changes In Grazing Regimes And Climatic Conditions In Northeastern Spain?, F. de Bello, J. Leps, M. T. Sebastià 2023 Forestry and Technology Centre of Catalonia, Spain

Do Species And Functional Diversity Indices Reflect Changes In Grazing Regimes And Climatic Conditions In Northeastern Spain?, F. De Bello, J. Leps, M. T. Sebastià

International Grassland Congress Proceedings

Understanding the mechanisms that maintain biodiversity in various ecosystems enables the development of management practices that prevent degradation (Canals & Sebastia, 2000). Each diversity index reflects some compositional properties and could be influenced differently by stress and disturbance factors (Magurran, 2004). In this study, we aim to reveal 1) which management practices and environmental factors affect biodiversity in rangelands of northeastern Spain and 2) the relationship between species diversity and functional diversity (SD and FD).


Impact Of Grazing Regimes On Mean Sward Height: Implications For The Management Of Bird Habitats In Agricultural Landscapes, M. Tichit, D. Durant, E. Kernéïs 2023 INRA, France

Impact Of Grazing Regimes On Mean Sward Height: Implications For The Management Of Bird Habitats In Agricultural Landscapes, M. Tichit, D. Durant, E. Kernéïs

International Grassland Congress Proceedings

Grazing in wet grasslands is a key process to manage foraging and nesting habitats for waders. Grazing has positive and negative effects related to the importance of sward conditions for these species and to nest-trampling by cattle. For settlement and nesting, lapwings need a short sward ( ≤ 10cm; see Durant et al., this congress). However, when lapwings settle in early spring, grasslands seldom are grazed yet, due to low soil carrying capacity. We studied the effect of autumn and winter grazing regimes on sward structure in early spring, and the effect of grazing regime in early spring on …


Soil Carbon Sequestration Under Three Years Of No-Till Forage Cropping Systems, D. H. Min, J. D. DeYoung, Richard Leep 2023 Michigan State University

Soil Carbon Sequestration Under Three Years Of No-Till Forage Cropping Systems, D. H. Min, J. D. Deyoung, Richard Leep

International Grassland Congress Proceedings

The effects of reduced tillage on soil organic carbon (SOC) are generally well established (Chan et al., 2002; Cabardella & Elliott, 1992). The effects of different crops are also somewhat understood (Drinkwater et al., 1998). However, many of these studies are done in the laboratory to study the effects of crop residues on SOC. Many forage-based systems have very little crop residue returned to the field. What residue does return is often in the form of manure or compost, which is usually broken down much more rapidly than most crop residues. The objective of this study is to …


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