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Articles 1081 - 1110 of 3173
Full-Text Articles in Earth Sciences
Adopting New Technologies For Grazing Lands: The Role Of Decision Systems, John A. Ludwig, Steve Marsden
Adopting New Technologies For Grazing Lands: The Role Of Decision Systems, John A. Ludwig, Steve Marsden
IGC Proceedings (1977-2023)
The management of Australia's arid and semi-arid grazing lands involves the consideration of many complex and interconnected issues related to both ecological and economic factors. Climates are highly variable across these lands and markets fluctuate widely; decision making is . difficult at the best of times, As new grazing and land management technologies become available through research organisations, such as CSIRO, the adoption of these technologies is a prime concern, Traditionally, State extension services provide this information to grazing land managers, which has proven effeclive for transferring information about current short-term problems (e,g,, locust plagues) and easy to apply products …
Applying "Farmer-First Research" In New Zealand, A F. Mcrae, F M. Anderson, R Brazendale
Applying "Farmer-First Research" In New Zealand, A F. Mcrae, F M. Anderson, R Brazendale
IGC Proceedings (1977-2023)
The disciplinary orientation and other characteristics of traditional agricultural research may result in farmers' research needs not being central to the research proces·s. A Farmer-First Research programme (FFR) has been initiated to complement the traditional research approach. This programme involves collaboration with hill country sheep and beef farmers chosen at random from across the fuff range of farmer circumstances. It sets out to diagnose and describe where scope· exists to Improve farmers' circumstances, and lo design and test relevant innovations on-farm. In addition to seeking to improve research output for far1ners, the· programme has the objective of evaluating the Farmer-First …
Technology Transfer Strategies For Products Of Environmental Research And Development Projects, N D. Macleod, J A. Taylor, P.G H. Van Beek, P N. Vance
Technology Transfer Strategies For Products Of Environmental Research And Development Projects, N D. Macleod, J A. Taylor, P.G H. Van Beek, P N. Vance
IGC Proceedings (1977-2023)
Potentially high net benefits from Research and Development on sustainable grazing systems will not be captured unless the outcomes are adopted. Adoption is a complex process, often requiring integration with other technologies, and specialised extension packages. Technology transfer strategies based on experiences with relatively simple innovations are unsuited to more complex environmental innovations, A 6-stage interactive process involving researchers, extension specialists and potential end-users is suggested.
Development Of Environmental And Agricultural Professionalism, Robert F. Barnes, Thomas J. Hall
Development Of Environmental And Agricultural Professionalism, Robert F. Barnes, Thomas J. Hall
IGC Proceedings (1977-2023)
The American Society of Agronomy {ASA) is' co-ordinating the development of a \ioluritary certification programme for the men and women who··make nutrient management strategies for farmers .• This paper examines the need, "history and obstacles in developing a crop advisor certification programme. Past arid proposed state and national legislative initiatives have indicated to some industry leaders that certification programmes' will be needed ·to operate in the coming regulat6ry environment. Other members· of industry· feel chat voluntary certification will bring on mandated programmes, The' differences in outlook, the diversity of the audience and the academic orientation of ASA ·have all created …
Grazier's Pattern Of Understanding Vegetation In The Semi-Arid Rangelands Of New South Wales, S.M M. Kersten, R L. Ison
Grazier's Pattern Of Understanding Vegetation In The Semi-Arid Rangelands Of New South Wales, S.M M. Kersten, R L. Ison
IGC Proceedings (1977-2023)
A matrix ranking (MR) technique was used by graziers in western New South Wales to rank rangeland plants according to preference. Graziers preferred a variety of plant species in their paddocks: "bushes" and "50f1 feed", perennials and annuals, winter-and summergrowing plants, on both stock-based and non-stock-based criteria, The criteria for evaluation were rarely independent of each other nor of different soil types on the grai:ier's property. Drought resistance was perceived as one of the more important criteria, followed by stock-based criteria such as "nutritious", "palatable" or "quick fattening" stock feed. The utility of MR for allowing graziers' knowledge to be …
Composition Of The Fractions Of Dry, Mature Subterranean Clover Digested In Vivo And In Vitro, L Klein, S K. Baker
Composition Of The Fractions Of Dry, Mature Subterranean Clover Digested In Vivo And In Vitro, L Klein, S K. Baker
IGC Proceedings (1977-2023)
A modified pepsin-cellulase procedure was used to improve the prediction of in vivo digestibility of dry, mature subterranean clovers (Trifolium subterraneum). Feed, faeces, and the residues from this /11 vitro procedure and the i11 vitro procedure of Tilley & Terry were analysed for protein, ash and fibre fractions lo determine the composition of the cell-wall functions that were digested. The extent of digestion of the cell-wall fractions differed between the two in vitro procedures, but the cell-wall fraction that was digested contained similar proportions of cellulose, hemicellulose, protein and lignin. The cellulose and protein contents of the cell-wall digested …
Effect Of Plant Leaf Age On The Production Of Tannins, Phenols, Proanthocyanidins And Flavanols In Eulalia Villosa, M M. Wolfson, E W. Du Toit, P Chesselet
Effect Of Plant Leaf Age On The Production Of Tannins, Phenols, Proanthocyanidins And Flavanols In Eulalia Villosa, M M. Wolfson, E W. Du Toit, P Chesselet
IGC Proceedings (1977-2023)
Histochemical and biochemical analyses have confirmed the presence of condensed tannins in a number of southern African tropical grasses. The ability to precipitate proteins, total phenols, condensed tannin and proanthocyanidin levels were significantly higher in mature leaves of Eulalia villosa than in young leaves. The ratio of condensed tannin to Jlavan 3,4-diols indicated that the young leaf material contained more monomeric unpolymerised flavan 3,4-diol units than mature leaves. The trend is repeated in the ratio 'of proanthocyanidin to flavan-4-ols, These low molecular weight proanthocyanidin precursors probably do not have the ability to precipitate proteins, The histochemical tests can be used …
Effect Of Inoculants And Absorbents Incorporated In Grass Silage On Silage Quality, Effluent Production And Animal Performance, Raymond Jones
Effect Of Inoculants And Absorbents Incorporated In Grass Silage On Silage Quality, Effluent Production And Animal Performance, Raymond Jones
IGC Proceedings (1977-2023)
Unwilled ryegrass crops (151 kg DM) were enslled in 70-t bunker silos. Crop analysis (g/kg/DM) was water-soluble carbohydrates 153, nitrogen 24.1 and predicted digestibility (DOMD) 0.67. Molassed sugar beet feed pellets were incorporated at a rate of 25 kg/t in the harvested crop with or without inoculant treatment ("Live Systems", MMB, UK), and compared with a control silage with no additive. Absorbent addition with or without inoculant significantly reduced silage pH and ammonia-N compared with the control. Inoculant treatment further increased lactic acid content. Silage effluent production was reduced by up to 33% by absorbent inclusion with effluent DM losses …
Near-Infrared Spectroscopy Analysis Of The Nutrient Content Of Dairy Pastures, R C. Kellaway, C Stimson, R J. Tassell
Near-Infrared Spectroscopy Analysis Of The Nutrient Content Of Dairy Pastures, R C. Kellaway, C Stimson, R J. Tassell
IGC Proceedings (1977-2023)
Pasture samples from temperate and tropical species were collected before and after grazing, at regular intervals, on 3 dairy farms in New South Wales over a period of 3 years. All samples (n=693) were analysed on a near-infrared (NIR) spectrophotometer with a scanning monochromator. Subsets of samples selected for calibration and validation, were analysed by wet chemistry methods for estimated metabolisable energy (MID), crude protein (CP), organic matter (OM), acid-detergent fibre (ADF), Ca, P, Mg, K, Na, S, Cu, Mn and Zn. These data were used lo develop NIR equations using partial least squares analyses. Standard errors of laboratory analysis …
Influence Of Oxygen Leakage Through Stretch Film On Quality Of Round Bale Silage, P Lingvall, C M. Pettersson, P Wilhelmsson
Influence Of Oxygen Leakage Through Stretch Film On Quality Of Round Bale Silage, P Lingvall, C M. Pettersson, P Wilhelmsson
IGC Proceedings (1977-2023)
The ensiling-process is based on anaerobic conditions. Therefore, it is important to get "air tight" parcels covering big-bale silage. Wrapping round bales wilh stretch film has improved silage quality, and reduced diy matter (OM) and energy losses. In this experiment we studied the influence of stretch film quality, film thickness, .storage temperature and storage place on fermentation, microbial growth/ and DM losses. Additionally, oxygen permeability of stretch film wrapped in 4 or 6 layers around artificial bales (metal) and DM losses was tested In a model. High storage temperature, low total film thickness and high film permeability to oxygen increased …
Renewable Energy Perception And Policy Implementation In Rural Communities: Case Studies In The Ohio And Tennessee River Valleys, Madeline Petty
Renewable Energy Perception And Policy Implementation In Rural Communities: Case Studies In The Ohio And Tennessee River Valleys, Madeline Petty
Masters Theses & Specialist Projects
Utility-scale renewable energy development allows clean energy production to fulfill energy demand and mitigate climate change. Development of utility-scale renewable energies such as wind and solar energy requires expansive tracts of land, typically found in rural areas. Rural center communities in the United States (U.S.) exhibit unique characteristics and ideologies that influence individuals’ perceptions of renewable energy about climate change. This research aimed to understand rural residents’ perception of renewable energy by surveying six rural center communities with varying levels of renewable energy. Surveys were distributed electronically to residents in these communities via mailers, digital ads, flyers, press releases, and …
Rotary Spading To Ameliorate Soil Water Repellence, Department Of Primary Industries And Regional Development, Western Australia
Rotary Spading To Ameliorate Soil Water Repellence, Department Of Primary Industries And Regional Development, Western Australia
Natural resources factsheets
One-off deep cultivation can reduce the severity of soil water repellence by mixing some of the repellent topsoil into the wettable subsoil and bringing wettable subsoil to the surface.
Rotary spading or deep cultivation increases water infiltration by providing pathways for water entry; diluting the water repellent soil with non-repellent soil; increasing the breakdown of soil organic matter causing water repellence; in some soil types, spading and other deep cultivation can lift subsoil with higher clay content to the surface.
Deep cultivation increases the risk of wind and water erosion. To minimise the risk of erosion, follow the guidelines on …
Polygenetic Cave Sedimentation And Speleogenesis In The Mccloud Limestone Of Northern California, Niles Lathrop
Polygenetic Cave Sedimentation And Speleogenesis In The Mccloud Limestone Of Northern California, Niles Lathrop
Masters Theses & Specialist Projects
Caves in the Permian-aged, McCloud Limestone of the Klamath Mountains of Northern California preserve a diverse range of clastic sediments that represent broad-scale variations in paleo-hydrologic conditions and transport mechanisms that hint at varied modes of speleogenesis through local landscape development. Caves in the McCloud Limestone exhibit a range of cave passage geometries and arrangements that suggests periods of both hypogene and epigene cave development through temporal and spatial scales. This study evaluates the variability in the distribution, mineralogy, and transport mechanisms of clastic-cave sediments in seven hydrologically-distinct caves in the McCloud Limestone to establish relationships between clastic-cave sedimentation and …
Comprehensive Climate Vulnerability Assessment Of A Regional Karst Landscape For Hazard Mitigation Planning, Kara Brunot
Comprehensive Climate Vulnerability Assessment Of A Regional Karst Landscape For Hazard Mitigation Planning, Kara Brunot
Masters Theses & Specialist Projects
Climate change is the global phenomena affecting all sectors of society by creating conditions more conducive for the occurrence of extreme weather events. It is projected that the intensity and frequency of events will increase. Flooding, in particular, is projected to increase in frequency due to more intense precipitation events. Karst landscapes are especially vulnerable to climate change impacts because of their unique hydrology and geology. Karst flooding is most likely to occur from prolonged or intense rain events, which climate change will likely make more feasible. Areas are disproportionately affected by climate change due to population demographics and environmental …
Development And Application Of The Sinkhole Hazard Risk Index To Inform Karst Policy And Mitigation Planning, Meghan Puente
Development And Application Of The Sinkhole Hazard Risk Index To Inform Karst Policy And Mitigation Planning, Meghan Puente
Masters Theses & Specialist Projects
Sinkholes are geologic hazards that occur in karst landscapes and can be highly destructive and costly. Sinkhole mitigation plans and development policies are nonexistent at the federal level within the United States and vary significantly at the state level. The lack of a unified standard for sinkhole mitigation planning is partly due to a lack of available data and resources needed to assess sinkhole risk. While there are established sinkhole assessments within the literature, they focus more on the detection and prediction of sinkholes rather than a holistic approach to risk assessment. The goal of this study is to create …
Landuse And Microplastic Transport In Karst Groundwater Of South-Central Kentucky, Katie Norman
Landuse And Microplastic Transport In Karst Groundwater Of South-Central Kentucky, Katie Norman
Masters Theses & Specialist Projects
Groundwater in karst areas is susceptible to contamination from various sources of pollution. Microplastics are a prevalent source of pollution entering groundwater. This study examines karst groundwater in three areas of investigation. One point of interest is an area that is impacted by urban activities, the Lost River Groundwater Basin, which includes water drainage from the City of Bowling Green, Kentucky. Another study location is Great Onyx (GO) Spring, which is a part of the Great Onyx Groundwater Basin located in Mammoth Cave National Park, Kentucky, and that is relatively unimpacted by urban activities. The third point of interest is …
Developing A Controlled Traffic (Tramline) Farming System, Department Of Primary Industries And Regional Development, Western Australia
Developing A Controlled Traffic (Tramline) Farming System, Department Of Primary Industries And Regional Development, Western Australia
Grains and other field crops factsheets
Controlled traffic farming (CTF) is a farming system built on permanent wheel tracks where the crop zone and traffic lanes are permanently separated. It can improve profitability and sustainability.
Implements for seeding, spraying, spreading and harvesting have a particular span, or multiple of it, and all wheel tracks are confined to specific traffic lanes.
CTF increases profit by more yield, better grain quality, improved operation timeliness, and reduced costs. The environment can improve, with less nutrient leaching, less water erosion, better water infiltration, and less greenhouse gas emission. Implementation needs a clear, long-term plan, and prioritisation of soil health.
Another …
Transformation Of Organic To Inorganic Nitrogen In Nh4 +-Illite-Bearing And Ga-Al-Ree-Rich Bituminous Coals: Evidence From Nitrogen Isotopes And Functionalities, Qian Wang, Shifeng Dai, Victor P. Nechaev, David French, Ian Graham, Lei Zhao, Shaowei Zhang, Yang Liang, James C. Hower
Transformation Of Organic To Inorganic Nitrogen In Nh4 +-Illite-Bearing And Ga-Al-Ree-Rich Bituminous Coals: Evidence From Nitrogen Isotopes And Functionalities, Qian Wang, Shifeng Dai, Victor P. Nechaev, David French, Ian Graham, Lei Zhao, Shaowei Zhang, Yang Liang, James C. Hower
Earth and Environmental Sciences Faculty Publications
Nitrogen is one of the most important elements and mainly occurs as organic forms in coal, and in a few cases, in an inorganic form. Organic nitrogen in coal is mainly derived from the proteins of plants and micro-organisms but sources of inorganic nitrogen remain controversial. One hypothesis for the source of inorganic nitrogen is the organic matter of coal, but this lacks strong evidence. In the Daqingshan Coalfield of Inner Mongolia, northern China, an igneous intrusion in the east of the coalfield led to a coal rank increase from the Hailiushu through the Datanhao mines to the Adaohai mine …
Fine-Scale Mangrove Species Classification Based On Uav Multispectral And Hyperspectral Remote Sensing Using Machine Learning, Yuanzheng Yang, Zhouju Meng, Jiaxing Zu, Wenhua Cai, Jiali Wang, Hongxin Su, Jian Yang
Fine-Scale Mangrove Species Classification Based On Uav Multispectral And Hyperspectral Remote Sensing Using Machine Learning, Yuanzheng Yang, Zhouju Meng, Jiaxing Zu, Wenhua Cai, Jiali Wang, Hongxin Su, Jian Yang
Earth and Environmental Sciences Faculty Publications
Mangrove ecosystems play an irreplaceable role in coastal environments by providing essential ecosystem services. Diverse mangrove species have different functions due to their morpho- logical and physiological characteristics. A precise spatial distribution map of mangrove species is therefore crucial for biodiversity maintenance and environmental conservation of coastal ecosystems. Traditional satellite data are limited in fine-scale mangrove species classification due to low spatial resolution and less spectral information. This study employed unmanned aerial vehicle (UAV) technology to acquire high-resolution multispectral and hyperspectral mangrove forest imagery in Guangxi, China. We leveraged advanced algorithms, including RFE-RF for feature selection and machine learning models …
Land-Use Change As A Major Driver For Mid-20th-Century Flood Intensity Reduction In The Southeastern Us, Zhixiong Shen, Nicholas Conway, Shaowu Bao, Samuel Muñoz, Andreas Lang
Land-Use Change As A Major Driver For Mid-20th-Century Flood Intensity Reduction In The Southeastern Us, Zhixiong Shen, Nicholas Conway, Shaowu Bao, Samuel Muñoz, Andreas Lang
Marine Science
Land-use changes affect hydrologic processes, but their impact on flooding remains obscure amid increasingly heavy precipitation. Instrumental records are short relative to land-use change history and inadequate for flood attribution studies. Here we integrate a high-resolution paleodischarge record spanning the past ∼200 years from the largest basin in the Southeastern United States with instrumental data and hydrological modeling. We find that the 100 yr flood magnitude for large regional rivers exhibits 50%–75% reductions in the mid-20th century. We attribute at least 50% of the reductions to a regional shift from widespread agricultural land to conservation and reforestation and the rest …
Zebra Limestone From The Gypsum Valley Salt Diapir, Colorado, Rebecca Navarrette
Zebra Limestone From The Gypsum Valley Salt Diapir, Colorado, Rebecca Navarrette
Open Access Theses & Dissertations
Zebra rocks displaying alternating light and dark-colored millimeter to centimeter thick bands of crystals have been found at the Gypsum Valley salt diapir, Colorado in the Paradox Basin where they are associated with gypsic diapiric caprock. Elucidating their origin may provide crucial information about intermittent fluid flow at the margin of salt diapirs and about Zebra rock formation, which often is associated with carbonate-hosted lead-zinc mineralization (Mississippi Valley Type, MVT) and hydrothermal dolomite -hosted hydrocarbon reservoirs.
The Gypsum Valley Zebra rocks consist of calcite, i.e., it is a Zebra limestone. It shows a finely crystalline light banding and coarsely crystalline …
Palynostratigraphy And Bayesian Age Stratigraphic Model Of New Ca-Id-Tims Zircon Ages From The Walloon Coal Measures, Surat Basin, Australia, K. Sobczak, J. Cooling, T. Crossingham, H. G. Holl, M. Reilly, J. Esterle, J. L. Crowley, C. Hannaford, M. T. Mohr, Z. Hamerli, S. Hurter
Palynostratigraphy And Bayesian Age Stratigraphic Model Of New Ca-Id-Tims Zircon Ages From The Walloon Coal Measures, Surat Basin, Australia, K. Sobczak, J. Cooling, T. Crossingham, H. G. Holl, M. Reilly, J. Esterle, J. L. Crowley, C. Hannaford, M. T. Mohr, Z. Hamerli, S. Hurter
Geosciences Faculty Publications and Presentations
The Surat Basin hosts significant coal and coal seam gas resources. New high-precision CA-TIMS U/Pb zircon ages from tuffs and Bayesian age stratigraphic models are combined with palynology from fine-grained sedimentary rocks and zircon trace elements to provide further chronostratigraphic and biostratigraphic constrains on the Walloon Coal Measures in the eastern margin of the Surat Basin and infer the palaeoenvironment and tectonic setting. The tuff ages range from 165.88 ± 0.11 Ma to 158.84 ± 0.05 Ma, with those from the stratigraphically lower Taroom Coal Measures ranging from 165.88 ± 0.11 to 163.05 ± 0.08 Ma and Juandah Coal Measures …
Silica Fault Mirror Development Along The Cordillera Blanca Detachment Fault, Peru, Kayla Michelle Chaudoir
Silica Fault Mirror Development Along The Cordillera Blanca Detachment Fault, Peru, Kayla Michelle Chaudoir
All Graduate Theses and Dissertations, Fall 2023 to Present
Earthquakes occur along planes of geologic weakness called faults. Thin, light-reflective surfaces on faults are called fault mirrors and often considered signatures of previous earthquakes along these faults. The Cordillera Blanca mountain range in the Peruvian Andes provides a natural laboratory to explore meter scale exposures of fault mirrors. Three naturally formed fault mirror samples were collected from the Cordillera Blanca detachment fault which runs along the edge of the Cordillera Blanca mountain range. Prior work on this fault reveals that it is capable of destructive earthquakes every few thousand years and is a significant earthquake hazard to the surrounding …
Shaking Off The Rust: Unraveling The Depositional And Diagenetic History Of Enigmatic Ferroan Dolostones In The Cambrian Bright Angel Formation, Tonto Group, Grand Canyon, Joseph J. Clevenger
Shaking Off The Rust: Unraveling The Depositional And Diagenetic History Of Enigmatic Ferroan Dolostones In The Cambrian Bright Angel Formation, Tonto Group, Grand Canyon, Joseph J. Clevenger
All Graduate Theses and Dissertations, Fall 2023 to Present
Within the siliciclastic-sediment-dominated Bright Angel Formation (BAF) of the iconic Cambrian sedimentary strata (Tonto Group) in Grand Canyon National Park, Arizona, workers have identified and named prominent reddish-brown cliffs breaking up the generally slope-forming unit near, but separated from, its upper contact with the limestone-dominated Muav Formation, the "Rusty Brown Dolostones" (RBDs). Previous hypotheses suggest that the RBDs are chemically and physically altered tongues of the Muav Formation intercalated with the BAF at increasingly higher stratigraphic positions from west to east within the Canyon. A genetic association between the Muav Formation and the RBDs, as well as between the RBDs …
Assessing Soil Properties & Suitability For Optimized Irrigation Development In Sudan, Northern Africa, Suhib O. Hamid
Assessing Soil Properties & Suitability For Optimized Irrigation Development In Sudan, Northern Africa, Suhib O. Hamid
Department of Agricultural and Biological Systems Engineering: Masters Project Reports
In Chapter 1, soil properties essential for efficient irrigation are thoroughly assessed. Factors such as soil texture, infiltration rates, and nutrient content are analyzed to provide insights into the selection of modern irrigation systems. Utilizing data collected from 3,192 locations through GPS and laboratory analyses, alongside sophisticated ranking systems, the research determines the most suitable irrigation methods for specific soil series. Findings highlight the remarkable efficiency of drip irrigation across various soil types, contrasting with the consistently lower performance of surface irrigation. The chapter emphasizes the significance of considering soil variability, evapotranspiration, and investment factors in selecting irrigation methods for …
Rock Wall Fracturing As A Potential Control On River Valley Width In The Buffalo National River, Arkansas, Kindle Hon
Rock Wall Fracturing As A Potential Control On River Valley Width In The Buffalo National River, Arkansas, Kindle Hon
Graduate Theses and Dissertations
Quantifying bedrock properties that control the persistence of fallen rock material (talus) along bedrock walls bounding river valleys may be a key factor in understanding what controls the rate at which these river valleys widen. My work is a component of a collaborative research project focused on the overarching hypothesis that the persistence vs. erodibility of talus that buffers river valley walls can be a first-order control on valley widening rates. I hypothesize that the primary control for creating erodible or persistent talus is the fracture spacing of bedrock valley walls as it sets the maximum block size of collapsed …
Environments And Controls Of Erosional Bedforms In Soluble Channels, Ethan W. Oleson
Environments And Controls Of Erosional Bedforms In Soluble Channels, Ethan W. Oleson
Graduate Theses and Dissertations
Erosional bedforms, such as scallops, preserve valuable information on the paleohydrologic conditions forming soluble channels in karst systems. While these bedforms are commonly used to interpret past conditions, questions about their formation remain. Mathematical models of speleogenesis in turbulent flow predict that the conditions for forming scallops do not occur in natural carbonate systems. However, scallops are readily found in caves throughout the world. This conundrum has several possible resolutions, but each lacks field-based observations. We present a field-based study of the environments and controls of scallops in gypsum, limestone, and dolostone caves. Our results are based on field observation, …
Characterizing Groundwater Flow Across The Barrier Island-High Marsh Interface, Dean Michael Wrobel
Characterizing Groundwater Flow Across The Barrier Island-High Marsh Interface, Dean Michael Wrobel
Electronic Theses and Dissertations
The freshwater resources of barrier islands are influenced by a variety of hydrogeologic factors, which create unique regions of groundwater composition. Factors including evapotranspiration, geologic constraints, tidal forcing, and meteoric inputs influence subterranean flow creating a groundwater salinity gradient throughout the island-marsh setting which directly influences the spatial distribution of dominant vegetation on the island. Rising sea levels and variation in local climate may alter the hydrologic balance on barrier islands, potentially shifting salinity gradients and ecological baselines on short timescales. The intrusion of saltwater into the barrier island freshwater system could result in the shifting of ecotones and potential …
Exploring Intraplate Seismicity In The Midwest, Alexa Fernández
Exploring Intraplate Seismicity In The Midwest, Alexa Fernández
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
Intraplate seismicity represents a notable occurrence within the stable North American Craton. This research explores the potential sources of stresses that could reactivate older faults and influence seismic activity within this region. Among these sources, the enduring impact of the last glacial period is considered, which includes continued glacial isostatic adjustments (GIA). During GIA the lithosphere rebounds due to the retreating ice, and the forebulge caused by far-field flexure in response to the glacial load, collapses. This results in significant faulting, fracturing, and seismic activity associated with the deglaciation phase. The adjustment of the lithosphere manifests as both near surface …
Applying Circuit Theory To Describe Changes In Structural Landscape Connectivity In Response To Wildfire, Christian Ross Nielsen
Applying Circuit Theory To Describe Changes In Structural Landscape Connectivity In Response To Wildfire, Christian Ross Nielsen
School of Natural Resources: Dissertations, Theses, and Student Research
Understanding and conserving ecological connectivity is critical to the preservation of vulnerable landscapes. Circuit theory, in which landscapes are imagined as circuit boards with varying resistances to the flow of current, is being increasingly used to model spatially explicit connectivity of landscapes and to inform land management and conservation decision-making. Utilizing continuous, quantitative estimates of percent cover by five land cover functional groups to create a conductance surface, this study expanded upon an established application of circuit theory that used the open-source software Circuitscape to model species-agnostic, omnidirectional connectivity. This model was automated using Python to create time-series connectivity maps …