Life Sciences Commons^™

Addressing Soil Carbon Sequestration Response From Multispecies Dairy Forage Systems And Modeling Rangeland Beef Cow Dry Matter Intake Using Precision Enteric Emissions Measurements, Lillian J. Mcfadden

Electronic Theses and Dissertations

Regenerative agriculture is a pressing matter for the dairy industry to address cropland sustainability and carbon sequestration. One regenerative management practice that has been identified to help with row crop sustainability for key metrics like soil organic carbon (SOC) is complex covers. When producers use complex covers one of the main challenges is that it takes time to detect a change in SOC. However, simulation models are a tool that can be used to help determine if a regenerative practice is a strategy that gives the best results (i.e., increased SOC) while aligning with long-term production goals. Therefore, our objectives …

Phosphorus Dynamics In Restored Riparian Wetlands On Former Agricultural Land In Vermont, Adrian Robert Hendrick Wiegman

Graduate College Dissertations and Theses

Wetland restoration has numerous potential ecological and societal benefits, one of which is the retention of phosphorus (P) and consequent protection of downstream water bodies from eutrophication. Past studies focused on influents to and effluents from a variety of wetland types have documented net P retention. However, some wetland systems are less effective at P capture and wetland P retention capacity can change over time. Certain wetland types - especially riparian wetlands restored on former agricultural land - remain understudied. In Vermont, most of the over 4000 potential wetland restoration sites in the Lake Champlain Basin are located on current …

Influence Of Physical Variability Of Highly Weathered Sedimentary Rock On Nitrate In Area 3 Of The Enigma Field Research Site At Y-12, Erin Kelly

Masters Theses

Uranium processing and waste storage in unlined waste ponds leached contaminants into the groundwater at Y-12, Oak Ridge, Tennessee, from the 1950s to 1980s. Groundwater wells near the S-3 ponds have had the highest nitrate concentrations of groundwater anywhere in the world (>10,000 mg/L). For reference, the maximum contaminant level for nitrate in drinking water set by the U.S. Environmental Protection Agency is 10 mg/L. Since 2012, the ENIGMA (Ecosystems and Networks Integrated with Genes and Molecular Assemblies) group has been characterizing, monitoring, and conducting field experiments to understand the interactions between contaminants, microbes, and the subsurface. The goals …

Modeling Stromatolite Formation With Diffusion-Limited Aggregation, Laura E. Stevens

Graduate Student Theses, Dissertations, & Professional Papers

Stromatolites, microbialites, and other microbially induced sedimentary structures exist in the rock record as far back as 3.6 billion years ago and continue to form in the present day. Better characterizing these structures and better understanding how they form is crucial in distinguishing these biosignatures from similar, abiotic structures, which can help us to understand the conditions of early Earth and early Mars. To that end, I have modified DLA 3D EXT, an open-source stromatolite modeling program, to more closely reflect the process of microbial trapping-and-binding by filamentous microbes in a calcite-precipitating hot spring system. This modified program includes a …

Modeling The Impact Of Grazing On Water Budgets, Ying Zhao, Stephan Peth, Julia Krümmelbein, Bettina Ketzer, Yingzhi Gao, Christian Bernhofer, Rainer Horn

IGC Proceedings (1997-2023)

No abstract provided.

Economic Trade-Offs Of Novel Forage Use In Livestock Production Systems: Insights From Australia, Marta Monjardino, Neil D. Macleod, Dean K. Revell

IGC Proceedings (1997-2023)

Globally, livestock are a major component of agricultural systems and natural resource management, as well as an important contributor to nutrition and livelihoods, but are often undervalued (Herrero et al., 2009). In Australia, livestock production systems occupy half of the available land and contribute to ~50% of gross agricultural production. The main livestock systems are beef cattle grazing at low intensity in the arid and semi-arid regions of northern and central Australia; and sheep flocks integrated in crop-livestock systems in the temperate zone of southern Australia (Bell et al., 2014). Despite increased physical productivity (changes in outputs relative …

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The goals of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and legally feasible option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed MAR harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services modeling; and …

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The aims of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and legally feasible option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed MAR harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services modeling; and …

Reducing Equifinality Using Isotopes In A Process-Based Stream Nitrogen Model Highlights The Flux Of Algal Nitrogen From Agricultural Streams, William I. Ford, James F. Fox, Erik Pollock

Biosystems and Agricultural Engineering Faculty Publications

The fate of bioavailable nitrogen species transported through agricultural landscapes remains highly uncertain given complexities of measuring fluxes impacting the fluvial N cycle. We present and test a new numerical model named Technology for Removable Annual Nitrogen in Streams For Ecosystem Restoration (TRANSFER), which aims to reduce model uncertainty due to erroneous parameterization, i.e., equifinality, in stream nitrogen cycle assessment and quantify the significance of transient and permanent removal pathways. TRANSFER couples nitrogen elemental and stable isotope mass‐balance equations with existing hydrologic, hydraulic, sediment transport, algal biomass, and sediment organic …

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The aims of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and permittable option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed Managed Aquifer Recharge (MAR) harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services …

Evaluating And Predicting Agricultural Management Effects Under Tile Drainage Using Modified Apsim, Robert W. Malone, N. Huth, P. S. Carberry, Liwang Ma, Thomas C. Kaspar, Douglas L. Karlen, T. Meade, Ramesh S. Kanwar, Philip Heilman

Douglas L Karlen

An accurate and management sensitive simulation model for tile-drained Midwestern soils is needed to optimize the use of agricultural management practices (e.g., winter cover crops) to reduce nitrate leaching without adversely affecting corn yield. Our objectives were to enhance the Agricultural Production Systems Simulator (APSIM) for tile drainage, test the modified model for several management scenarios, and then predict nitrate leaching with and without winter wheat cover crop. Twelve years of data (1990–2001) from northeast Iowa were used for model testing. Management scenarios included continuous corn and corn–soybean rotations with single or split N applications. For 38 of 44 observations, …

Forecasting Climate Change Impacts On The Distribution Of Wetland Habitat In The Midwestern United States, Heath Garris, Randall Mitchell, Lauchlan Fraser, Linda Barrett

Randall J. Mitchell

Shifting precipitation patterns brought on by climate change threaten to alter the future distribution of wetlands. We developed a set of models to understand the role climate plays in determining wetland formation on a landscape scale and to forecast changes in wetland distribution for the Midwestern United States. These models combined 35 climate variables with 21 geographic and anthropogenic factors thought to encapsulate other major drivers of wetland distribution for the Midwest. All models successfully recreated a majority of the variation in current wetland area within the Midwest, and showed that wetland area was significantly associated with climate, even when …

Forecasting Climate Change Impacts On The Distribution Of Wetland Habitat In The Midwestern United States, Heath Garris, Randall Mitchell, Lauchlan Fraser, Linda Barrett

Linda R. Barrett

Shifting precipitation patterns brought on by climate change threaten to alter the future distribution of wetlands. We developed a set of models to understand the role climate plays in determining wetland formation on a landscape scale and to forecast changes in wetland distribution for the Midwestern United States. These models combined 35 climate variables with 21 geographic and anthropogenic factors thought to encapsulate other major drivers of wetland distribution for the Midwest. All models successfully recreated a majority of the variation in current wetland area within the Midwest, and showed that wetland area was significantly associated with climate, even when …

Interdisciplinary Modeling For Water-Related Issues Graduate Course, Laurel Saito, Alexander Fernald, Timothy Link

All ECSTATIC Materials

The science and management of aquatic ecosystems is inherently interdisciplinary, with issues associated with hydrology, atmospheric science, water quality, geochemistry, sociology, economics, environmental science, and ecology. Addressing water resources issues in any one discipline invariably involves effects that concern other disciplines, and attempts to address one issue often have consequences that exacerbate existing issues or concerns, or create new ones (Jørgensen et al. 1992; Lackey et al. 1975; Straskraba 1994) due to the strongly interactive nature of key processes (Christensen et al. 1996). Thus, research and management of aquatic ecosystems must be interdisciplinary to be most effective, but such truly …

Toward “Optimal” Integration Of Terrestrial Biosphere Models, Christopher R. Schwalm, Deborah N. Huntzinger, Joshua B. Fisher, Anna M. Michalak, Kevin Bowman, Philippe Ciais, Robert Cook, Bassil El-Masri, Daniel Hayes, Maoyi Huang, Akihiko Ito, Atul Jain, Anthony W. King, Hiumin Lei, Junjie Liu, Chaoqun (Crystal) Lu, Jaifu Mao, Shushi Peng, Benjamin Poulter, Daniel Ricciuto, Kevin Schaefer, Xiaoying Shi, Bo Tao, Hanqin Tian, Weile Wang, Yaxing Wei, Jia Yang, Ning Zeng

Chaoqun (Crystal) Lu

Multimodel ensembles (MME) are commonplace in Earth system modeling. Here we perform MME integration using a 10-member ensemble of terrestrial biosphere models (TBMs) from the Multiscale synthesis and Terrestrial Model Intercomparison Project (MsTMIP). We contrast optimal (skill based for present-day carbon cycling) versus naïve (“one model-one vote”) integration. MsTMIP optimal and naïve mean land sink strength estimates (−1.16 versus −1.15 Pg C per annum respectively) are statistically indistinguishable. This holds also for grid cell values and extends to gross uptake, biomass, and net ecosystem productivity. TBM skill is similarly indistinguishable. The added complexity of skill-based integration does not materially change …

Water And Energy Balance Response Of A Riparian Wetland To The Removal Of Phragmites Australis, Phillip Mykleby

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

Vegetation and climate both play integral roles in water availability, particularly for arid to semi-arid regions. Changes in these variables can lead to extreme shortages in water for regions that rely on water for crop irrigation (i.e., the Great Plains). The objective of this study is to evaluate the impacts of vegetation on water availability in the Republican River basin in central Nebraska. Decreases in streamflow have been observed in the river basin for many years and, as a result, an invasive riparian plant species (Phragmites australis) is being removed in an effort to reduce evapotranspiration and reclaim …

Slides: Groundwater Declines, Climate Change And Approaches To Adaptation, Katharine Jacobs

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Katharine Jacobs, Director of the Arizona Water Institute, University of Arizona

37 slides

Application Of Simplified Phosphorus Transport Models To Pasture Fields In Northwest Arkansas, Dwayne R. Edwards, C. T. Haan, Andrew N. Sharpley, John F. Murdoch, Tommy C. Daniel, Philip A. Moore Jr.

Biosystems and Agricultural Engineering Faculty Publications

Runoff transport of phosphorus (P) is often predicted from simple equations with parameters determined from data applicable primarily to row-cropped and fallow cover conditions. The applicability, accuracy, and precision of such P transport prediction equations under pasture situations are less well defined. The objectives of this study were to determine parameters of simplified runoff P transport equations for pasture fields and to assess the accuracy and precision of the equations. Runoff, sediment yield, soluble P transport, and particulate P transport data were collected from four pasture fields in northwestern Arkansas. Runoff event enrichment ratios and extraction coefficients were computed, and …