Earth Sciences Commons^™

Floodplain Forests Vegetation Dynamics Driven By Water Deficits Across Scales, Nga Thanh Nguyen

LSU Doctoral Dissertations

Restoration of floodplain ecosystems relies on identifying the most crucial hydrologic process which has been altered by human and climate. Flooding is a well-known dominant hydrologic process for floodplain ecosystems, but surprisingly little is known about drought's role in structuring ecosystems. In addition, several issues remained uncertain, such as the nature of drought within floodplains and the sensitivity of floodplain species-specific growth to climate. These gaps of understanding have in common in missing observations of mechanistic pathways of vegetation response to water deficits at multiple scales in time and space.Generally, this research contributed to floodplain management by expanding our understanding …

Modelling Grazing And Burning In Communal Rangelands To Help Understand Trade-Offs Between Production, Carbon, And Water, H. J. Hawkins, M. Moradzadeh, M. L. Vermeire, Farai Chikomba, L. Wu

IGC Proceedings (1977-2023)

Rangelands cover more than 80% of South Africa’s land area, providing critical ecosystem services, livelihoods and cultural values related to livestock. Communally owned rangelands are often overgrazed and subject to runaway fires but lack of data limits our understanding of how these threats impact production. In this transdisciplinary project, we use models to test hypotheses and predict future scenarios as a planning tool for resource-poor communal farmers. We think that moderate grazing and fire regimes will increase overall production and carbon sequestration with uncertain trade-offs for water and nutrient cycling. To test this, we trained two process-based biogeochemical models (DAYCENT …

Timescales Of Magma Transport In The Columbia River Flood Basalts, Determined By Paleomagnetic Data, Joseph Biasi, Leif Karlstrom

Other Staff Materials

Flood basalts represent major events in Earth History, in part because they are linked to large climate perturbations and mass extinctions. However, the durations of individual flood basalt eruptions, which directly impact potential environmental crises, are poorly constrained. Here we use a combination of paleomagnetic data and thermal modeling to create a magnetic geothermometer (MGT) that can constrain the active transport lifetime of magmatic conduits and intrusions. We apply the MGT technique to eight feeder dike segments of the Columbia River basalts (CRB), demonstrating that some dike segments were actively heating host rocks for less than one month, while other …

Modeling Forage Yield Losses For Crop Insurance In Eastern Canada, I. Duchesne‐Ortiz, Gilles Bélanger, L. Martel, Guy Allard

IGC Proceedings (1977-2023)

No abstract provided.

Spatial And Temporal Patterns Of River Incision And Terrace Deposition In Response To Climate And Tectonics In Southern Taiwan, Dominique M. Shore

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Geologists often look at the Earth’s surface to understand the underlying processes that cause mountain formation. As tectonic forces drive uplift of Earth’s surface, processes of erosion transport sediment to lower elevations. Climate can play a large role in landscape formation as well as increased precipitation, accelerating rates of erosion. Rivers leave markers of landscape evolution through terrace landforms, former river floodplains that are left behind when rivers incise into a valley. To better understand landscape response to uplift, this research investigated the initial linkages between uplift, hillslope erosion (mass wasting) and river incision. At some point, it is thought …

Climate, Vegetation, And Weathering Across Space And Time In Lake Tanganyika (Tropical Eastern Africa), Sarah J. Ivory, Michael M. Mcglue, Cara Peterman, Patrick Baldwin, Joseph Lucas, Andrew Cohen, James Russell, Justina Saroni, Emma Msaky, Ishmael Kimirei, Michael Soreghan

Earth and Environmental Sciences Faculty Publications

Climate and vegetation influence weathering rates and processes; however, evaluating the effects of each and feedbacks between systems, has yet to be accomplished for many types of landscapes. A detailed understanding of how these processes interact to shape landscapes is particularly crucial for reconciling future scenarios of changing climate, where profound alterations to both the biosphere and geosphere are anticipated. In the tropics, ecosystem services, such as soil and water quality, are linked to both vegetation and weathering processes that form a strong control on natural resources that are the foundation of many communities’ daily subsistence. This understanding is further …

Coastal Watershed Monitoring And Management: Geomorphology, Geochemistry, And Hydrologic Modeling Of Los Peñasquitos Creek, Ca, Ravleen Khalsa-Basra

Theses

Rivers in semi-arid climates are directly influenced by local geographic and hydrologic conditions and impacted by modifications to hydrology via urbanization. Changes can influence erosion, morphology, habitat sustainability, and watershed health. In highly urbanized southern California coastal regions, these rare open spaces provide vital ecosystem services. Los Peñasquitos Creek in San Diego County is one such watershed. Using stream surveying and laboratory methods we quantified channel characteristics, grain size distribution, total metal concentration [M], organic carbon (%OC), and phosphate to longitudinally characterize the creek for improved management. Results identified three distinct reaches in the watershed (upper, middle, lower). Downstream, depth …

Rock Glacier Hydrological Significance In A Warming World: A Geoecological Transect In The North Cascades, Washington, Jessica Abadie Coffey

All Master's Theses

Mountain environments are some of the most climate-sensitive areas on the planet. Due to recent warming trends, the 0℃ isotherm is rising in elevation and subsequently melting glaciers, snowpack, and permafrost. However, rock glaciers are a type of permafrost that is climate-resilient; therefore, research on their distribution and water volume equivalence (WVEQ) will be increasingly valuable in a warming world.

The purpose of this research was to determine the hydrological significance of different altitude belts of alpine permafrost in Washington State’s North Cascades. Additionally, this study analyzed how much rock glacier permafrost will be exposed to melting temperatures with climate …

Influence Of Some Climatic Elements On Radon Concentration In Saeva Dupka Cave, Bulgaria, Peter Nojarov, Petar Stefanov, Karel Turek

International Journal of Speleology

This study reveals the influence of some climatic elements on radon concentration in Saeva Dupka Cave, Bulgaria. The research is based mainly on statistical methods. Radon concentration in the cave is determined by two main mechanisms. The first one is through penetration of radon from soil and rocks around the cave (present all year round, but has leading role during the warm half of the year). The second one is through thermodynamic exchange of air between inside of the cave and outside atmosphere (cold half of the year). Climatic factors that affect radon concentration in the cave are temperatures (air, …

Impacts Of Environmental Conditions On Fleas In Black-Tailed Prairie Dog Burrows, Julia E. Poje, Tonie Rocke, Michael D. Samuel

United States Geological Survey: Staff Publications

Sylvatic plague, caused by the bacterium Yersinia pestis and transmitted by fleas, occurs in prairie dogs of the western United States. Outbreaks can devastate prairie dog communities, often causing nearly 100% mortality. Three competent flea vectors, prairie dog specialists Oropsylla hirsuta and O. tuberculata, and generalist Pulex simulans, are found on prairie dogs and in their burrows. Fleas are affected by climate, which varies across the range of black-tailed prairie dogs (Cynomys ludovicianus), but these effects may be ameliorated somewhat due to the burrowing habits of prairie dogs. Our goal was to assess how temperature and precipitation …

Modeling Holocene Peatland Carbon Accumulation In North America, Qianlai Zhuang, Sirui Wang, Bailu Zhao, Filipe Aires, Catherine Prigent, Zicheng Yu, Jason K. Keller, Scott Bridgham

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Peatlands are a large carbon reservoir. Yet the quantification of their carbon stock still has a large uncertainty due to lacking observational data and well‐tested peatland biogeochemistry models. Here, a process‐based peatland model was calibrated using long‐term peat carbon accumulation data at multiple sites in North America. The model was then applied to quantify the peat carbon accumulation rates and stocks within North America over the last 12,000 years. We estimated that 85–174 Pg carbon was accumulated in North American peatlands over the study period including 0.37–0.76 Pg carbon in subtropical peatlands. During the period from 10,000 to 8,000 years …

Geology, Soils And Climate Of The Margaret River Wine Region, Peter J. Tille, Angela Stuart-Street, Peter S. Gardiner

All other publications

This report is an extract from the broader description and analysis of the Geology, soils and climate of Western Australia's wine regions. It expands on the brief descriptions in the second edition of 'Viticulture' (Coombe & Dry 2004) concerning the soils and landscapes of Western Australia’s main wine growing regions. We have tailored this report extract to the specific needs of the Margaret River wine region. It contains local soil names and soil-landscape zones and systems maps.

The wine industry recognises the importance of giving customers an understanding of the vines’ environment and how that may influence wine character …

A 30-Year Agroclimatic Analysis Of The Snake River Valley American Viticultural Area - Descriptive And Predictive Methods, Charles L. Becker

Boise State University Theses and Dissertations

Climate change poses serious threats to global agriculture, however some localities and crops may benefit from increasing temperatures. Grape production in southern Idaho may be a beneficial example as vineyard acreage has increased over 300% since the designation of the Snake River American Viticultural Area (SRVAVA) in 2007. We perform a statistical characterization of agroclimate within the SRVAVA that centers around four primary objectives: utilization of a novel, 30-year high resolution climate dataset to provide insight and agrometrics unavailable at coarser resolutions, climatic implications of the unique topography within the SRVAVA, identification of statistical trends, and correlation of SRVAVA climate …

Refractory Black Carbon (Rbc) Variability In A 47-Year West Antarctic Snow And Firn Core, Marquetto Luciano, Susan Kaspari, Jefferson Cardia Simões

All Faculty Scholarship for the College of the Sciences

Black carbon (BC) is an important climate-forcing agent that affects snow albedo. In this work, we present a record of refractory black carbon (rBC) variability, measured from a 20m deep snow and firn core drilled in West Antarctica (79°55’34.600” S, 94°21’13.3”W, 2122m above sea level) during the 2014–2015 austral summer. This is the highest elevation rBC record from West Antarctica. The core was analyzed using the Single Particle Soot Photometer (SP2) coupled to a CETAC Marin-5 nebulizer. Results show a well-defined seasonality with geometric mean concentrations of 0.015 μg L^-1 for the wet season (austral summer–fall) and 0.057 μg …

Landscape-Scale Patterns Of Fire And Drought On The High Plains, Usa, Paulette L. Ford, Charles Jackson, Matthew Reeves, Benjamin Bird, David Turner

IGC Proceedings (1977-2023)

We examine 31 years (1982-2012) of temperature, precipitation and natural wildfire occurrence data for Federal and Tribal lands to determine landscape-scale patterns of drought and fire on the southern and central High Plains of the western United States. The High Plains states of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas and Wyoming have been in the midst of ongoing extreme drought, experiencing below normal precipitation and above normal temperatures for the past several years. Climate change is predicted to have multiple effects on fire regimes. Longer periods of drought conditions, coupled with hot, dry and windy weather, provide …

Comprehensive And Agricultural Greenhouse Gas Emissions Inventories For Nebraska And The Midwest As Baselines For Climate Change Mitigation, Eric R. Holley

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

Climate change is the paramount challenge of today for a sustainable future. Mitigation of greenhouse gas (GHG) emissions is necessary to reduce the associated risks and impacts on society. Using the EPA’s SIT and literature review, comprehensive GHG-emissions inventories were developed for the state of Nebraska over 25 years (1990-2015) and agricultural GHG emissions inventories were developed for the Midwest U.S for one year (2016). Nebraska’s net emissions increased from 56.2 million metric tons of carbon dioxide equivalent (MMtCO₂e) in 1990 to 87.4 MMtCO₂e in 2016. Agriculture was found to be the sector with the most …

Integrated Farming Systems In The Frame Work Of Bio-Economic Modelling For Sustainable Development Of Small And Marginal Farmers Under Changing Climatic Scenario, U. K. Behera

IGC Proceedings (1977-2023)

In order to meet the multiple objectives of poverty reduction, food security, competitiveness and sustainability several researchers have recommended to adopt integrated farming systems (IFS). IFS is an approach in which different landbased enterprises are integrated within the bio-physical and socio-economic situations taking farmers preference and goal in to consideration. This is a multi-disciplinary approach and very effective for solving the problems of small and marginal farmers (Gangwar, 1993). Under the gradual shrinking of land holding in India and other developing countries, it is necessary to go for IFS to make farming more profitable and sustainable. In agricultural research and …

Declining Water Resources And Environmental Degradation: A Case Of The Thulokhola Watershed In The Nuwakot District Of Nepal, Durga D. Poudel, Timothy W. Duex

IGC Proceedings (1977-2023)

Climate change alters the hydrology of a watershed through changes on precipitation patterns, extreme rain events, increase on temperatures, degradation of forest and soil resources and drought conditions. Drought conditions create stress on agricultural crops, forests, drinking water supply for human and wildlife as well as water supply for industrial uses. Flooding destroys crops, infrastructures, private properties, and results in loss of life. Climate change impacts both the availability as well as the quality of water resources as extreme rain events tend to alter water infrastructures and pollute water sources.

In Nepal, climate change impacts include degradation of resource and …

Fibre Quality In Timothy, Festulolium And Tall Fescue Around First Cut, Magnus A. Halling

IGC Proceedings (1977-2023)

Fibre quality and available energy expressed as iNDF (indigestible neutral detergent fibre) decrease with maturity stage in timothy (Nordheim-Viken and Volden 2009). It is widely accepted that fibre quality also decreases with plant age in other forage grasses. However, climate factors such as temperature and water availability can interact with maturity stage in determining iNDF (Nordheim-Viken and Volden 2009). In the Norfor system, iNDF is an important measure of available energy in forage evaluation for ruminants (Åkerlind et al. 2011). This study examined how fibre quality in different forage grasses was affected by maturity stage and climate.

Long Term Ground Based Precipitation Data Analysis: Spatial And Temporal Variability, Luciano Rodriguez

Computational and Data Sciences (PhD) Dissertations

This dissertation evaluates response variables (classifiers) on various models applied to the detection of El Niño Southern Oscillation (ENSO) on California’s seven climate divisions by using modeled and gauge (in-situ/ground) precipitation measurements and various climate indices. Three scientific studies were conducted as part of this research for evaluation of spatial and temporal ENSO events from modeled and gauge data using: 1) Wavelets 2) Autoregressive-moving-average (ARMA) model / Empirical Mode Decomposition (EMD) 3) Vector Generalized Linear Model (VGLM). This dissertation aims to propose and evaluate a methodology for developing a model to measure ENSO events accurately. The hypothesis is that precipitation …

Spatial And Temporal Controls On Streamflow Variability In The San Juan Mountains, Colorado, Christopher Lewis Hancock

Electronic Theses and Dissertations

This project characterizes and examines changes to the annual hydroclimatic cycle throughout alpine regions of Colorado with a focus on trends in snowpack and snowmelt hydrology. Datasets analyzed for this research include 79 SNOTEL sites throughout Colorado (24 in the San Juan Mountains) which provide climate metrics for Water Years 1988-2018. Impacts on streamflow are evaluated in the San Juan Region through a network of 11 USGS stream gauges. Correlation matrices and linear regression methods examine the relative controls on the magnitude and timing of discharge, and trend detection using the regional Kendall test quantifies the rate of change within …

Climate And Surging Of Donjek Glacier, Yukon, Canada, Ellyn M. Enderlin

Geosciences Faculty Publications and Presentations

Links between climate and glacier surges are poorly understood but are required to enable prediction of surges and mitigation of associated hazards. Here, we investigate the role of snow accumulation, rain, and temperature on surge periodicity, area changes, and timing of surge initiation since the 1930s at Donjek Glacier, Yukon, Canada. Snow accumulation measured in three ice cores collected at Eclipse Icefield indicates that a cumulative accumulation of 15.5 ± 1.46 or 16.6 ± 2.0 m w.e. occurred in the ten to twelve years between each of its last eight surges, depending on ice motion spatiotemporal offset corrections. Although we …

Estimating Abiotic Thresholds For Sagebrush Condition Class In The Western United States, Stephen Boyte, Bruce K. Wylie, Yingxin Gu, Donald J. Major

United States Geological Survey: Staff Publications

Sagebrush ecosystems of the western United States can transition from extended periods of relatively stable conditions to rapid ecological change if acute disturbances occur. Areas dominated by native sagebrush can transition from species-rich native systems to altered states where non-native annual grasses dominate, if resistance to annual grasses is low. The non-native annual grasses provide relatively little value to wildlife, livestock, and humans and function as fuel that increases fire frequency. The more land area covered by annual grasses, the higher the potential for fire, thus reducing the potential for native vegetation to reestablish, even when applying restoration treatments. Mapping …

Evolution Of Extreme Continental Saline Environments: A Sedimentological Investigation Of Permo-Triassic Redbeds And Evaporites In Northern Ireland And Kansas, Anna Sofia S. Andeskie

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Permo-Triassic was a time of extreme environments, unusually warm and arid climates, and biotic crises. This study investigates Pangean environments and climate leading to extreme acid saline lake systems represented by the Permian Nippewalla Group of Kansas and the Triassic Mercia Mudstone Group of Northern Ireland. Sedimentological observations of the underlying rocks, the Permian Hutchinson Salt Member of Kansas and the Permian Belfast Harbour Evaporite Formation of Northern Ireland, help to understand trends in environmental and climatic conditions leading to these extreme environments. This dissertation also refines the geographic extent of extreme acid saline lake and groundwater systems through …

Larger-Scale Ocean-Atmospheric Patterns Drive Synergistic Variability And World-Wide Volatility Of Wheat Yields, Ehsan Najafi, Indrani Pal, Reza Khanbilvardi

Advanced Science Research Center

Diagnosing potential predictability of global crop yields in the near term is of utmost importance for ensuring food supply and preventing socio-economic consequences. Previous studies suggest that a substantial proportion of global wheat yield variability depends on local climate and larger-scale ocean-atmospheric patterns. The science is however at its infancy to address whether synergistic variability and volatility (major departure from the normal) of multi-national crop yields can be potentially predicted by larger-scale climate drivers. Here, using observed data on wheat yields for 85 producing countries and climate variability from 1961–2013, we diagnose that wheat yields vary synergistically across key producing …

Climate Diagnostics Of The Extreme Floods In Peru During Early 2017, Rackhun Son, Shih-Yu Simon Wang, Wan-Ling Tseng, Christian W. Barreto Schuler, Emily Becker, Jin-Ho Yoon

Plants, Soils, and Climate Faculty Publications

From January through March 2017, a series of extreme precipitation events occurred in coastal Peru, causing severe floods with hundreds of human casualties and billions of dollars in economic losses. The extreme precipitation was a result of unusually strong recurrent patterns of atmospheric and oceanic conditions, including extremely warm coastal sea surface temperatures (SST) and weakened trade winds. These climatic features and their causal relationship with the Peruvian precipitation were examined. Diagnostic analysis and model experiments suggest that an atmospheric forcing in early 2017, which was moderately linked to the Trans-Niño Index (TNI), initiated the local SST warming along coastal …

Evidence Of Variable Climate And Resources During The Late Pleistocene And Holocene At Gona, Ethiopia, Marie White

Steeplechase: An ORCA Student Journal

The African Humid Period (AHP) spanned a period of approximately 15 to 5 thousand years ago (ka) and resulted in Northern and Eastern Africa being wetter than today. This climate change event impacted flora, fauna, and humans to an unknown extent. Much of the work on the AHP across Eastern Africa utilizes lacustrine and marine proxies rather than river-based (fluvial). Gona, located in the Afar region of Ethiopia, is known for its extensive archaeological and fossil records in fluvial deposits. However, the paleoenvironment of the AHP at Gona has not been investigated. This study uses stratigraphy, geochronology, and paleopedology to …

Improving Thorium-230 Determination In Marine Sediment, Katherine Mateos

Independent Study Project (ISP) Collection

Our oceans are intimately related to the climate of our planet. Paleoceanographic approaches aim to study oceans through geologic time to improve models of future climate. Radioisotopes provide us with chemical tracers that help us understand change through time. The uraniumseries decay chain contains thorium-230, a decay product of uranium-234. This isotope is useful to paleoceanographers in its disequilibrium to its parent isotope and in determining the flux of sediment falling to the ocean floor. In order to use 230Th to study oceans, we must be able to accurately measure the amount of thorium in sediment samples. Thorium is found …

Modeling Extreme Heat Events Using Global Reanalysis Data: An Assessment Of Current Climate Data And The Need For Improved Weather Station Data In Tennessee, John Reasons

Electronic Theses and Dissertations

Wet Bulb Globe Temperature (WBGT) is used to assess categorical heat stress risk factors for individuals working in outdoor environments and to provide guidelines for work/rest ratios and water intake. The variables required to compute WBGT are used by meteorologists for many purposes and are available through the Copernicus Program which was implemented by European Centre for Medium-Range Weather Forecasts (ECMWF) to provide users access to ECMWF Re-Analysis (ERA) historical database. WBGT values for Tennessee during National Weather Service (NWS) issued excessive heat warnings were calculated to determine the need for additional advisories based on WBGT guidelines. Monthly average WBGT …

Changes In Mammalian Abundance Through The Eocene–Oligocene Climate Transition In The White River Group Of Nebraska, Usa, Robert Gillham

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Marine records show major cooling during the Eocene-Oligocene Climate Transition (EOCT). Most proxy studies in the White River Group suggest drying across the EOCT, and some suggest cooling. The lower resolution continental record has hindered a direct correlation of the marine climate record to Nebraska. I explore various correlation schemes and what they imply for faunal changes. This study compiles and analyzes data from 4,875 specimens in the University of Nebraska State Museum (UNSM) collection to test the hypothesis that climate change across the Eocene-Oligocene (E-O) boundary caused significant abundance changes in mammals. A series of binning schemes was created. …