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2020

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Articles 1441 - 1470 of 3204

Full-Text Articles in Earth Sciences

Geospatial Applications To Mitigate Concentrated Animal Feeding Operations From Impacting Surface Water Resources, Elias Rex Jun 2020

Geospatial Applications To Mitigate Concentrated Animal Feeding Operations From Impacting Surface Water Resources, Elias Rex

Electronic Theses, Projects, and Dissertations

Concentrated Animal Feeding Operations (CAFOs) offer the ability to meet the rising demands of population growth by housing large amounts of livestock on relatively small areas of land, using medication to accelerate their maturation, and reusing waste products as fertilizers. However, there is a growing abundance of literature related to land use configurations and their effects on water resources, many of which highlight agriculture as a primary contributor of nutrients and fecal bacteria found in surrounding water resources. The purpose of this study is to advance the current knowledge surrounding CAFO land-use and its effect on tributaries within the Cape …


Potential Predictability Of Net Primary Production In The Ocean, Kristen M. Krumhardt, Nicole S. Lovenduski, Matthew C. Long, J. Y. Luo, K. Lindsay, S. Yeager, Cheryl S. Harrison Jun 2020

Potential Predictability Of Net Primary Production In The Ocean, Kristen M. Krumhardt, Nicole S. Lovenduski, Matthew C. Long, J. Y. Luo, K. Lindsay, S. Yeager, Cheryl S. Harrison

School of Earth, Environmental, & Marine Sciences Faculty Publications

Interannual variations in marine net primary production (NPP) contribute to the variability of available living marine resources, as well as influence critical carbon cycle processes. Here we provide a global overview of near-term (1 to 10 years) potential predictability of marine NPP using a novel set of initialized retrospective decadal forecasts from an Earth System Model. Interannual variations in marine NPP are potentially predictable in many areas of the ocean 1 to 3 years in advance, from temperate waters to the tropics, showing a substantial improvement over a simple persistence forecast. However, some regions, such as the subpolar Southern Ocean, …


Effect Of Pecan Variety And The Method Of Extraction On The Antimicrobial Activity Of Pecan Shell Extracts Against Different Foodborne Pathogens And Their Efficacy On Food Matrices, Veerachandra K. Yemmireddy, Cameron Cason, Juan Moreira, Achyut Adhikari Jun 2020

Effect Of Pecan Variety And The Method Of Extraction On The Antimicrobial Activity Of Pecan Shell Extracts Against Different Foodborne Pathogens And Their Efficacy On Food Matrices, Veerachandra K. Yemmireddy, Cameron Cason, Juan Moreira, Achyut Adhikari

School of Earth, Environmental, & Marine Sciences Faculty Publications

The shells of pecans are a rich source of bioactive compounds with potential inhibitory activity against various pathogenic microorganisms. This study investigated the antimicrobial activity of pecan shell extracts as effected by the type of cultivar and the method of extraction against various foodborne bacterial pathogens. Defatted shell powders of 19 different pecan cultivars were subjected to aqueous and ethanolic extraction (1:20 w/v) procedures, respectively. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of lyophilized pecan shell extracts dissolved in deionized water containing 5% DMSO (v/v) were determined against multiple strains of Listeria monocytogenes, Salmonella enterica, and …


Soil Fatigue Hazard Screening Analyses Framework For Spacio-Temporally Clustered Induced Seismicity With Examples Of Damage Potential Due To Liquefaction, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz Jun 2020

Soil Fatigue Hazard Screening Analyses Framework For Spacio-Temporally Clustered Induced Seismicity With Examples Of Damage Potential Due To Liquefaction, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Current studies that focus solely on the cause of the increase in seismicity neglect to include considerations for effects of small magnitude cluster events on federal infrastructure. These effects can be almost undetectable at first, but if left unchecked can evolve into a larger issue. The need to reassess and potentially modify the established risk assessment practices for evaluations of federal infrastructure needs to be reviewed to ensure the continued ability of the structure to function as intended. The U.S. Army Corps of Engineers (USACE) is responsible for hydroelectric power, flood protection, recreational areas, navigational channels and water supply along …


Neural Network Models For Nuclear Treaty Monitoring: Enhancing The Seismic Signal Pipeline With Deep Temporal Convolution, Joshua T. Dickey Jun 2020

Neural Network Models For Nuclear Treaty Monitoring: Enhancing The Seismic Signal Pipeline With Deep Temporal Convolution, Joshua T. Dickey

Theses and Dissertations

Seismic signal processing at the IDC is critical to global security, facilitating the detection and identification of covert nuclear tests in near-real time. This dissertation details three research studies providing substantial enhancements to this pipeline. Study 1 focuses on signal detection, employing a TCN architecture directly against raw real-time data streams and effecting a 4 dB increase in detector sensitivity over the latest operational methods. Study 2 focuses on both event association and source discrimination, utilizing a TCN-based triplet network to extract source-specific features from three-component seismograms, and providing both a complimentary validation measure for event association and a one-shot …


Categorizing Zonal Productivity On The Continental Shelf With Nutrient-Salinity Ratios, Jongsun Kim, Piers Chapman, Gilbert Rowe, Steven F. Dimarco Jun 2020

Categorizing Zonal Productivity On The Continental Shelf With Nutrient-Salinity Ratios, Jongsun Kim, Piers Chapman, Gilbert Rowe, Steven F. Dimarco

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

  • Identifying riverine influence on productivity in the northern Gulf of Mexico
  • Use of nutrient/salinity plots to differentiate inputs from two rivers
  • Verifying Rowe-Chapman (2002) hypothesis with in situ data

Abstract

Coastal ocean productivity is often dependent on riverine sources of nutrients, yet it can be difficult to determine how far the influence of the river extends. The northern Gulf of Mexico (GOM) receives freshwater and nutrients discharged mainly from the Mississippi and Atchafalaya Rivers. We used nutrient/salinity relationships to (i) differentiate the nutrient inputs of the two rivers and (ii) determine the potential extent of the zones where productivity …


Physical And Chemical Properties Of Soils In Gambari Forest Reserve Near Ibadan, South Western Nigeria., Akintola O. Opeyemi Dr, Bodede Idayat Adewunmi Dr, Abiola Isaac Oluwaseyi Dr Jun 2020

Physical And Chemical Properties Of Soils In Gambari Forest Reserve Near Ibadan, South Western Nigeria., Akintola O. Opeyemi Dr, Bodede Idayat Adewunmi Dr, Abiola Isaac Oluwaseyi Dr

Journal of Bioresource Management

The different features of soil greatly affect the flora and vegetative diversity of a forest. The physical and chemical characteristics of soils in Onigambari Forest Reserve were evaluated to assess the fertility and productivity status of the soils. Fifteen soil samples collected from different sample locations were analyzed for soil texture (sand, silt and clay), bulk density, porosity, pH, organic matter, total nitrogen, available phosphorus, exchangeable bases (Na, K, Ca and Mg) and available micronutrients (Zn, Cu, Fe and Mn). Texturally, the studied soils were loamy sand and sandy loam with percentage of sands (71.2-84.2 %), silts (7.4-10.4 %) and …


A Geochemical Perspective On The Hydrocarbon Compositional Variation Within East Malay Basin: Implication For Oil Exploration, Mohd Sharef Nurfadhila Jun 2020

A Geochemical Perspective On The Hydrocarbon Compositional Variation Within East Malay Basin: Implication For Oil Exploration, Mohd Sharef Nurfadhila

Student Works (2020-2029)

Malay Basin is a prospective basin which perceived to be matured basin in terms of hydrocarbon generating potential. Many significant oil discoveries made since 1970’s includes Seligi, Pulai, Tapis and Bekok oil fields. These fields have been producing until now. Despite its matured stage, there are still more oil discoveries in various parts of Malay Basin until now. Oil discoveries include light and high density oils with various challenges in oil development project. This dissertation focuses on oil fields in East Malay Basin particularly Lerek, Chermingat, Lawang and Serudon oil fields. The objectives of this research are to study the …


Characterizing Surface Water From Space With Microwave Remote Sensing: Advancing Conventional And Emerging Approaches, Katherine Jensen Jun 2020

Characterizing Surface Water From Space With Microwave Remote Sensing: Advancing Conventional And Emerging Approaches, Katherine Jensen

Dissertations, Theses, and Capstone Projects

The extent and dynamics of land surface inundation vary tremendously across the globe. Accurate spatial representation of terrestrial surface water is of critical importance for management and conservation of biodiversity and other ecosystem services associated with freshwater. Furthermore, surface water maps representing dynamic characteristics of inundated areas are also valuable for the development of wetland inventories and to assess the role of wetlands as major natural sources of methane to the atmosphere. Despite the importance of these environments in global processes and to current and future climate, the extent and dynamics of global wetlands remain poorly characterized and modeled.

The …


Effects Of Endophyte Infection On The Response Of Achnatherum Inebrians To Water Stress And Nitrogen Fertilizer Under Controlled Growth Conditions, X. S. Li, X. Z. Zhang, X. Gu May 2020

Effects Of Endophyte Infection On The Response Of Achnatherum Inebrians To Water Stress And Nitrogen Fertilizer Under Controlled Growth Conditions, X. S. Li, X. Z. Zhang, X. Gu

IGC Proceedings (1977-2023)

No abstract provided.


Stress-State And Injection-Rate Dependent Damage Processes During The Hydraulic Fracturing Of Granite, Gayani Sasendrika Gunarathna May 2020

Stress-State And Injection-Rate Dependent Damage Processes During The Hydraulic Fracturing Of Granite, Gayani Sasendrika Gunarathna

Dissertations

Hydraulic fracturing is a well-stimulation technique that is employed in field applications, such as enhanced geothermal systems (EGS) and shale oil/gas extraction. This research experimentally investigates the effect of the state of stress and injection rate on the hydraulic fracturing processes. In addition, a displacement discontinuity method (DDM) code, FROCK, is used to model the crack initiation and propagation in a granite specimen under hydraulic fracturing conditions. In order to conduct the experimental work, a test setup capable of applying a triaxial state of stress and water pressure inside pre-fabricated flaws cut in prismatic granite specimens is developed. Additionally, the …


Neogene Retroarc Foreland Basin Evolution, Sediment Provenance, And Magmatism In Response To Flat Slab Subduction, Western Argentina, Tomas N. Capaldi, Brian K. Horton, N. Ryan Mckenzie, Chelsea Mackaman-Lofland, Daniel F. Stockli, Gustavo Ortiz, Patricia Alvarado May 2020

Neogene Retroarc Foreland Basin Evolution, Sediment Provenance, And Magmatism In Response To Flat Slab Subduction, Western Argentina, Tomas N. Capaldi, Brian K. Horton, N. Ryan Mckenzie, Chelsea Mackaman-Lofland, Daniel F. Stockli, Gustavo Ortiz, Patricia Alvarado

Geoscience Faculty Research

Understanding the effects of flat slab subduction on mountain building, arc magmatism, and basin evolution is fundamental to convergent‐margin tectonics, with implications for potential feedbacks among geodynamic, magmatic, and surface processes. New stratigraphic and geochronological constraints on Cenozoic sedimentation and magmatism in the southern Central Andes of Argentina (31°S) reveal shifts in volcanism, foreland/hinterland basin development, sediment accumulation, and provenance as the retroarc region was structurally partitioned during slab flattening. Detrital zircon U‐Pb age distributions from the western (Calingasta basin), central (Talacasto and Albarracín basins), and eastern (Bermejo foreland basin) segments of the retroarc basin system preserve syndepositional volcanism and …


From Drought To Flood: A Water Balance Analysis Of The Tuolumne River Basin During Extreme Conditions (2015–2017), Andrew R. Hedrick, Danny Marks, Hans-Peter Marshall, James Mcnamara, Scott Havens, Ernesto Trujillo May 2020

From Drought To Flood: A Water Balance Analysis Of The Tuolumne River Basin During Extreme Conditions (2015–2017), Andrew R. Hedrick, Danny Marks, Hans-Peter Marshall, James Mcnamara, Scott Havens, Ernesto Trujillo

Geosciences Faculty Publications and Presentations

The degree to which the hydrologic water balance in a snow‐dominated headwater catchment is affected by annual climate variations is difficult to quantify, primarily due to uncertainties in measuring precipitation inputs and evapotranspiration (ET) losses. Over a recent three‐year period, the snowpack in California's Sierra Nevada fluctuated from the lightest in recorded history (2015) to historically heaviest (2017), with a relatively average year in between (2016). This large dynamic range in climatic conditions presents a unique opportunity to investigate correlations between annual water availability and runoff in a snow‐dominated catchment. Here, we estimate ET using a water balance approach where …


Contribution Of Vegetative Reproducton Of Leymus Chinensis And Carex Duriuscula To Population Persistence During Restoration Succession After Flood Disturbance In The Songnen Plains, China, Haiyan Li, Yunfei Yang May 2020

Contribution Of Vegetative Reproducton Of Leymus Chinensis And Carex Duriuscula To Population Persistence During Restoration Succession After Flood Disturbance In The Songnen Plains, China, Haiyan Li, Yunfei Yang

IGC Proceedings (1977-2023)

No abstract provided.


Root System Ecology Of Shrubs In Qilian Mountains Alpine Rhododendron Shrubland, Wenxia Cao, Degang Zhang, Fuzeng Hong May 2020

Root System Ecology Of Shrubs In Qilian Mountains Alpine Rhododendron Shrubland, Wenxia Cao, Degang Zhang, Fuzeng Hong

IGC Proceedings (1977-2023)

No abstract provided.


Sustainable Recultivation And Land Use On Karst Regions--Shrub System, Z. Q. Lai, S, M. Qin, Y. R. Chen, S. Z. Qin, M. Pogacnik, X. F. Yi, N. Yao, Y. L. Liang, D. Kompan, X. Su May 2020

Sustainable Recultivation And Land Use On Karst Regions--Shrub System, Z. Q. Lai, S, M. Qin, Y. R. Chen, S. Z. Qin, M. Pogacnik, X. F. Yi, N. Yao, Y. L. Liang, D. Kompan, X. Su

IGC Proceedings (1977-2023)

No abstract provided.


Sustainable Recultivation And Land Use On Karst Regions--Pasture System, Z. Q. Lai, Y. R. Chen, M. Pogacnik, S. Z. Qin, X. F. Yi, N. Yao, Y. L. Liang, J. H. Deng, X. F. Zhang, B. Zhang, H. J. Zhong, D. Kompan, X. J. Lu, X. Su, D. Y. Shen May 2020

Sustainable Recultivation And Land Use On Karst Regions--Pasture System, Z. Q. Lai, Y. R. Chen, M. Pogacnik, S. Z. Qin, X. F. Yi, N. Yao, Y. L. Liang, J. H. Deng, X. F. Zhang, B. Zhang, H. J. Zhong, D. Kompan, X. J. Lu, X. Su, D. Y. Shen

IGC Proceedings (1977-2023)

No abstract provided.


A Model For Managing An Endangered Species In Sandhills Rangeland, Kay L. Kottas, James Stubbendieck May 2020

A Model For Managing An Endangered Species In Sandhills Rangeland, Kay L. Kottas, James Stubbendieck

IGC Proceedings (1977-2023)

No abstract provided.


Quantifying Fluid-Wettable Effective Pore Space In The Utica And Bakken Oil Shale Formations, Qinhong Hu May 2020

Quantifying Fluid-Wettable Effective Pore Space In The Utica And Bakken Oil Shale Formations, Qinhong Hu

Earth & Environmental Sciences Datasets - Archive

Laboratory results from (U)SANS [(ultra) small angle neutron scattering] work conducted at NIST to be published at an American Geophysical Union (AGU) journal. (2020-05-26)


Benthic Nitrogen Dynamics In Response To Deltaic Succession, Anthropogenic Fertilization And Hurricane Events In An Emerging Coastal Deltaic Floodplain Within The Mississippi River Delta Plain, Song Li May 2020

Benthic Nitrogen Dynamics In Response To Deltaic Succession, Anthropogenic Fertilization And Hurricane Events In An Emerging Coastal Deltaic Floodplain Within The Mississippi River Delta Plain, Song Li

LSU Doctoral Dissertations

Increasing concentrations of nitrogenous fertilizer (NO3-) in rivers have potentially altered benthic nitrogen (N) cycling in coastal deltaic floodplains at the continental margins of major rivers. Here I evaluated the N removal capacity of a newly emergent coastal deltaic floodplain [Wax Lake Delta (WLD)] within the Mississippi River Delta Plain using continuous flow-through incubations. I investigated the response of benthic N dynamics in WLD to deltaic succession, anthropogenic fertilization and hurricane events. The estimated annual NO3- removal of 896 Mg N yr-1 in WLD accounts for 10 to 27% of total NO3- …


Experimental Increases In Diversity And Evenness Improve Productivity And Reduce Weed Invasion In Grassland Swards Over Three Years Across 12 European Sites, Laura Kirwan, Caroline Brophy, R. P. Collins, J. Connolly, J. A. Finn, A. Helgadottir, Andreas Lüscher, C. Porqueddu, M. T. Sebastià May 2020

Experimental Increases In Diversity And Evenness Improve Productivity And Reduce Weed Invasion In Grassland Swards Over Three Years Across 12 European Sites, Laura Kirwan, Caroline Brophy, R. P. Collins, J. Connolly, J. A. Finn, A. Helgadottir, Andreas Lüscher, C. Porqueddu, M. T. Sebastià

IGC Proceedings (1977-2023)

No abstract provided.


Fire And Vegetation Change In Coastal Grasslands, South Africa, Kevin P. Kirkman, B. P. A. Dalton May 2020

Fire And Vegetation Change In Coastal Grasslands, South Africa, Kevin P. Kirkman, B. P. A. Dalton

IGC Proceedings (1977-2023)

No abstract provided.


Studies On The Autecology Of Astragalus Caragana F. Et M In The Esfahan Province In Ira, M. Khodagholi, M. Esmaili Sharif, A. Ghaedi, M. Borhand, M. T. Feyze May 2020

Studies On The Autecology Of Astragalus Caragana F. Et M In The Esfahan Province In Ira, M. Khodagholi, M. Esmaili Sharif, A. Ghaedi, M. Borhand, M. T. Feyze

IGC Proceedings (1977-2023)

No abstract provided.


The Acacia Operation Project: A Pilot Activity For Combating Desertification And Improving The Livelihood Of Pastoralist In The Arid Rangelands Of Kenya, George A. Keya, M. Muga, B. Chikamai May 2020

The Acacia Operation Project: A Pilot Activity For Combating Desertification And Improving The Livelihood Of Pastoralist In The Arid Rangelands Of Kenya, George A. Keya, M. Muga, B. Chikamai

IGC Proceedings (1977-2023)

No abstract provided.


Impacts Of Grazing, Wildfire And Drought On Rodent Populations In A Semi-Arid Grassland Of Southwestern North America, L. J. Kennedy, Z. F. Jones, C. E. Bock, J. H. Bock May 2020

Impacts Of Grazing, Wildfire And Drought On Rodent Populations In A Semi-Arid Grassland Of Southwestern North America, L. J. Kennedy, Z. F. Jones, C. E. Bock, J. H. Bock

IGC Proceedings (1977-2023)

No abstract provided.


Stability, Recovery, And Resilience In Piosphere Systems In The Kruger National Park, Katherine J. Matchett, Kevin P. Kirkman, Craig D. Morris, Mike J. Peel May 2020

Stability, Recovery, And Resilience In Piosphere Systems In The Kruger National Park, Katherine J. Matchett, Kevin P. Kirkman, Craig D. Morris, Mike J. Peel

IGC Proceedings (1977-2023)

No abstract provided.


Contribution Of Lucerne And Red Clover To Succeeding Cereal Crops Yield, Žydrė Kadžiulienė, Zenonas Dabkevičius, Lina Šarūnaitė, Leonas Kadžiulis May 2020

Contribution Of Lucerne And Red Clover To Succeeding Cereal Crops Yield, Žydrė Kadžiulienė, Zenonas Dabkevičius, Lina Šarūnaitė, Leonas Kadžiulis

IGC Proceedings (1977-2023)

No abstract provided.


The Effect Of Environmental Factors On Plant Species Diversity And Productivity, K. H. Li, Y. K. Hu, C. F. Lu, W. M. E. Wu, W. L. Li May 2020

The Effect Of Environmental Factors On Plant Species Diversity And Productivity, K. H. Li, Y. K. Hu, C. F. Lu, W. M. E. Wu, W. L. Li

IGC Proceedings (1977-2023)

No abstract provided.


Temporal And Spatial Variation Of Arbuscular Mycorrhizal Fungi Spores In Seasonally Salt Stressed Grassland Using Medicago Sativa For Reclamation In Hexi Corridor, China, Liang Jin, Chang Wang, Guoliang Chen, Yin Zhao, Xiangwei Sun, Xiaojuan Wang May 2020

Temporal And Spatial Variation Of Arbuscular Mycorrhizal Fungi Spores In Seasonally Salt Stressed Grassland Using Medicago Sativa For Reclamation In Hexi Corridor, China, Liang Jin, Chang Wang, Guoliang Chen, Yin Zhao, Xiangwei Sun, Xiaojuan Wang

IGC Proceedings (1977-2023)

No abstract provided.


Effect Of Long‐Term Salt Stress On Antioxidative Enzyme Activities Of Nypa Forage (Distichlis Spicata Var. Yensen‐4a) And Tall Fescue (Festuca Arundinacea Schreb), Yaxiong Jia, Xianglin Li, Liqiang Wan, Feng He May 2020

Effect Of Long‐Term Salt Stress On Antioxidative Enzyme Activities Of Nypa Forage (Distichlis Spicata Var. Yensen‐4a) And Tall Fescue (Festuca Arundinacea Schreb), Yaxiong Jia, Xianglin Li, Liqiang Wan, Feng He

IGC Proceedings (1977-2023)

No abstract provided.