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Investigating Geochemical Processes Of Fluid-Rock Interactions On Materials Related To Energy And Environment, Zelong Zhang

LSU Doctoral Dissertations

Understanding the potential processes of radionuclides released from nuclear waste forms is essential to the safe disposal and containment of nuclear waste. Iodoapatite, a potential waste form for radioiodine, was chosen as a model system to examine the impact by common aqueous anions on iodine release processes. Four semi-dynamic leaching tests were performed using 0.1 mol/L NaCl, Na₂CO₃, Na₃PO₄, and Na₂SO₄ solutions respectively under 90 °C, 1 bar, fixed S/V ratio 5/m (sample surface area to solution volume), and with 24-hour replacement of the leaching solutions. Solution analysis and …

Heavy Metals In The Arctic: Distribution And Enrichment Of Five Metals In Alaskan Soils, Clarice R. Perryman, Jochen Wirsing, Kathryn A. Bennett, Owen Brennick, Apryl L. Perry, Nicole Williamson, Jessica G. Ernakovich

Faculty Publications

Metal contamination of food and water resources is a known public health issue in Arctic and sub-Arctic communities due to the proximity of many communities to mining and drilling sites. In addition, permafrost thaw may release heavy metals sequestered in previously frozen soils, potentially contaminating food and water resources by increasing the concentration of metals in freshwater, plants, and wildlife. Here we assess the enrichment of selected heavy metals in Alaskan soils by synthesizing publicly available data of soil metal concentrations. We analyzed data of soil concentrations of arsenic, chromium, mercury, nickel, and lead from over 1,000 samples available through …

Host Plant Resistance In Strawberries To Anthracnose And Colonization Of Crown And Root Tissue By Verticillium Dahliae And Macrophomina Phaseolina, Omar A. Gonzalez-Benitez

Master's Theses

Strawberries are considered an important crop in California where in 2018 it was in the top 5 valued fruit and vegetable commodities valued at $2.84 billion accounting for 88% of the total U.S. production. Strawberry production can be severely impacted by soilborne pathogens that can affect strawberry roots, crowns and leaves which can result in plant mortality. As much as 50 to 60% mortality can occur in one field. Pathogens responsible for such losses include Colletotrichum acutatum (syn.C. nymphaeae), Macrophomina phaseolina and Verticillium dahliae. With the phaseout of methyl bromide, host resistance and an understanding of host-pathogen interactions …

The Strawberry Rhizosphere Microbiome: Role On Plant Health And Nutrition, Eric Michael Boyd

Master's Theses

Microbial-root associations are important to help plants cope with abiotic and biotic stressors. Managing these interactions offers an opportunity for improving the efficiency and sustainability of agricultural production. By characterizing the bacterial and archaeal community (via 16S rRNA sequencing) associated with the bulk and rhizosphere soil of sixteen strawberry cultivars in two controlled field studies, we explored the relationships between the soil microbiome and plant resistance to two soilborne fungal pathogens of strawberry (Verticillium dahliae and Macrophomina phaseolina). Overall, the plants had a distinctive rhizosphere microbiome relative to the bulk soil, with higher abundances of known beneficial bacteria …

An Integrated Approach (Remote Sensing, Hydrogeology, Gis, And Statistical Modeling) To Identify The Distribution Of Shallow Groundwater Occurrences Over Southwest Saudi Arabia, Fahad Khudier Alshehri

Dissertations

Identifying shallow (near-surface) groundwater in arid and hyper-arid areas has significant societal benefits, yet it is a costly operation when traditional methods (geophysics and drilling) are applied over large domains. In this study, we developed and successfully applied methodologies that rely heavily on readily available temporal, visible and near-infrared, radar, and thermal remote sensing data sets and field data, as well as statistical approaches to map the distribution of shallow (1–5 m deep) groundwater occurrences in Al Qunfudah Province, Saudi Arabia and to identify the factors controlling their development. A four-fold approach was adopted: (1) constructing a digital database to …

Controls On Microbial And Oolitic Carbonate Sedimentation And Stratigraphic Cyclicity Within A Mixed Carbonate-Siliciclastic System: Upper Cambrian Wilberns Formation, Llano Uplift, Mason County, Texas, Usa, Daniel J. Lehrmann, A. W. Droxler, P. Harris, M. Minzoni, Dylan A. Droxler, H. H. Hopson, Caroline Kelleher, P. Khanna, Asmara A. Lehrmann, Adrien Lhemann, Grace Mabry, Lauren Mercado, J. M. Proctor, Pulkit Singh, Lindesy D. Yazbek

Earth and Environmental Geosciences Faculty Research

The upper Cambrian Wilberns Formation in central Texas records deposition on a low-gradient shelf within a mixed carbonate–siliciclastic tidal-flat system that changes offshore to subtidal shelf and open-marine oolitic skeletal shoals with large microbial mounds. Siliciclastic sediment is interpreted to have been delivered to the tidal flat by aeolian processes because of the narrow range in grain size and paucity of clay. Tidal influence is dominant as evidenced by reversing currents and desiccation on the tidal flat, and megaripples with reversing current indicators in offshore shoals. Intraclastic conglomerates were deposited in broad channels on the tidal flats during storm surges. …

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 …

Estimating Evapotranspiration Of A Riparian Forest Using Sap Flow Measurements, James R. Solum

Master's Theses

To close the water use budget of irrigated agricultural fields in floodplains with substantial riparian corridors, it is necessary to understand groundwater usage by dominant phreatophytic vegetation, particularly when the primary source of water for irrigation comes from groundwater abstraction. We report here results of estimated evapotranspiration (ET) of a riparian forest, which were based on measurements of sap flow in phreatophytic vegetation within a riparian corridor. The riparian corridor was within a study area 75 to 140 meters wide in the lower portion of the Scotts Creek watershed, which is bounded to the west by the Pacific Ocean in …

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 …

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 …

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, …

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.

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

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

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

IGC Proceedings (1977-2023)

No abstract provided.

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

IGC Proceedings (1977-2023)

No abstract provided.

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

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

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

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

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

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

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

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

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

IGC Proceedings (1977-2023)

No abstract provided.

Effects Of Various Cattle Grazing Regimes On Vernal Pool Grassland Diversity, J. T. Marty

IGC Proceedings (1977-2023)

No abstract provided.

Impacts Of Long-Term Phosphorus Fertilization And Addition Of Perennial Legumes On A Temperate Natural Grassland: I. Changes In Spieces Biodiversity And Stability, Martín Jaurena, Walter Ayala, José Terra, Raül Bermudez, Ethel Barrios, Ximena Lagomarsino

IGC Proceedings (1977-2023)

No abstract provided.

Influence Of Growing Season Rainfall Amount And Clipping Intensity On Aboveground Net Primary Productivity In Leyums Chinensis Steppe, Feng He, Xianglin Li, Liqiang Wan, Yaxiong Jia, Dan He

IGC Proceedings (1977-2023)

No abstract provided.