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Full-Text Articles in Physical Sciences and Mathematics

Introduction To Empowered Partnerships: Community-Based Participatory Action Research For Environmental Justice, Christopher M. Bacon, Saneta Devuono-Powell, Mary Louise Frampton, Tony Lopresti, Camille Pannu Feb 2017

Introduction To Empowered Partnerships: Community-Based Participatory Action Research For Environmental Justice, Christopher M. Bacon, Saneta Devuono-Powell, Mary Louise Frampton, Tony Lopresti, Camille Pannu

Mary Louise Frampton

This article introduces a special section on empowered partnerships that deepens a dialogue initiated during the 2010 symposium titled EmPowered Partnerships: Community-Based Participatory Action Research for Environmental Justice. The articles in this section will be divided between issues 1 and 2 of the Journal. After briefly reviewing the definitions and the steps associated with community-based participatory action research (CBPAR), we identify the synergies connecting the underlying principles and values of the environmental justice (EJ) movement and CBPAR. The principles-based comparison is part of an ongoing effort to craft a framework that produces research partnerships that are simultaneously more responsive to …


Assessment Of Optional Sediment Transport Functions Via The Complex Watershed Simulation Model Swat, Ruoyu Wang Jan 2017

Assessment Of Optional Sediment Transport Functions Via The Complex Watershed Simulation Model Swat, Ruoyu Wang

Ruoyu Wang

The Soil andWater Assessment Tool 2012 (SWAT2012) offers four sediment routing methods
as optional alternatives to the default simplified Bagnold method. Previous studies compared only
one of these alternative sediment routing methods with the default method. The proposed study
evaluated the impacts of all four alternative sediment transport methods on sediment predictions:
the modified Bagnold equation, the Kodoatie equation, the Molinas and Wu equation, and the
Yang equation. The Arroyo Colorado Watershed, Texas, USA, was first calibrated for daily flow.
The sediment parameters were then calibrated to monthly sediment loads, using each of the four
sediment routing equations. An automatic …


Assessing The Potential To Decrease The Gulf Of Mexico Hypoxic Zone With Midwest Us Perennial Cellulosic Feedstock Production, Andy Vanloocke, Tracy E. Twine, Christopher J. Kucharik, Carl J. Bernacchi Jan 2017

Assessing The Potential To Decrease The Gulf Of Mexico Hypoxic Zone With Midwest Us Perennial Cellulosic Feedstock Production, Andy Vanloocke, Tracy E. Twine, Christopher J. Kucharik, Carl J. Bernacchi

Andy VanLoocke

The goal of this research was to determine the changes in streamflow, dissolved inorganic nitrogen (DIN) leaching and export to the Gulf of Mexico associated with a range of large-scale dedicated perennial cellulosic bioenergy production scenarios within in the Mississippi–Atchafalaya River Basin (MARB). To achieve this goal, we used Agro-IBIS, a vegetation model capable of simulating the biogeochemistry of row crops, miscanthus and switchgrass, coupled with THMB, a hydrology model capable of simulating streamflow and DIN export. Simulations were conducted at varying fertilizer application rates (0–200 kg N ha -1) and fractional replacement (5–25%) of current row crops with miscanthus …


Expression Of Cyanobacterial Fbp/Sbpase In Soybean Prevents Yield Depression Under Future Climate Conditions, Iris H. Kohler, Ursula M. Ruiz-Vera, Andy Vanloocke, Michell L. Thomey, Tom Clemente, Stephen P. Long, Donald R. Ort, Carl J. Bernacchi Jan 2017

Expression Of Cyanobacterial Fbp/Sbpase In Soybean Prevents Yield Depression Under Future Climate Conditions, Iris H. Kohler, Ursula M. Ruiz-Vera, Andy Vanloocke, Michell L. Thomey, Tom Clemente, Stephen P. Long, Donald R. Ort, Carl J. Bernacchi

Andy VanLoocke

Predictions suggest that current crop production needs to double by 2050 to meet global food and energy demands. Based on theory and experimental studies, overexpression of the photosynthetic enzyme sedoheptulose-1,7-bisphosphatase (SBPase) is expected to enhance C3 crop photosynthesis and yields. Here we test how expression of the cyanobacterial, bifunctional fructose-1,6/sedoheptulose-1,7-bisphosphatase (FBP/SBPase) affects carbon assimilation and seed yield (SY) in a major crop (soybean, Glycine max). For three growing seasons, wild-type (WT) and FBP/SBPase-expressing (FS) plants were grown in the field under ambient (400 μmol mol−1) and elevated (600 μmol mol−1) CO2 concentrations [CO2] and under ambient and elevated temperatures (+2.7 …


A Realistic Meteorological Assessment Of Perennial Biofuel Crop Deployment: A Southern Great Plains Perspective, Melissa Wagner, Meng Wang, Gonzalo Miguez-Macho, Jesse Miller, Andy Vanloocke, Justin E. Bagley, Carl J. Bernacchi, Matei Georgescu Jan 2017

A Realistic Meteorological Assessment Of Perennial Biofuel Crop Deployment: A Southern Great Plains Perspective, Melissa Wagner, Meng Wang, Gonzalo Miguez-Macho, Jesse Miller, Andy Vanloocke, Justin E. Bagley, Carl J. Bernacchi, Matei Georgescu

Andy VanLoocke

Utility of perennial bioenergy crops (e.g., switchgrass and miscanthus) offers unique opportunities to transition toward a more sustainable energy pathway due to their reduced carbon footprint, averted competition with food crops, and ability to grow on abandoned and degraded farmlands. Studies that have examined biogeophysical impacts of these crops noted a positive feedback between near-surface cooling and enhanced evapotranspiration (ET), but also potential unintended consequences of soil moisture and groundwater depletion. To better understand hydrometeorological effects of perennial bioenergy crop expansion, this study conducted high-resolution (2-km grid spacing) simulations with a state-of-the-art atmospheric model (Weather Research and Forecasting system) dynamically …


Impacts Of Second-Generation Biofuel Feedstock Production In The Central U.S. On The Hydrologic Cycle And Global Warming Mitigation Potential, K. J. Harding, T. E. Twine, Andy Vanloocke, J. E. Bagley, J. Hill Jan 2017

Impacts Of Second-Generation Biofuel Feedstock Production In The Central U.S. On The Hydrologic Cycle And Global Warming Mitigation Potential, K. J. Harding, T. E. Twine, Andy Vanloocke, J. E. Bagley, J. Hill

Andy VanLoocke

Biofuel feedstocks provide a renewable energy source that can reduce fossil fuel emissions; however, if produced on a large scale they can also impact local to regional water and carbon budgets. Simulation results for 2005–2014 from a regional weather model adapted to simulate the growth of two perennial grass biofuel feedstocks suggest that replacing at least half the current annual cropland with these grasses would increase water use efficiency and drive greater rainfall downwind of perturbed grid cells, but increased evapotranspiration (ET) might switch the Mississippi River basin from having a net warm-season surplus of water (precipitation minus ET) to …


Candidate Perennial Bioenergy Grasses Have A Higher Albedo Than Annual Row Crops, Jesse N. Miller, Andy Vanloocke, Nuria Gomez-Casanovas, Carl J. Bernacchi Jan 2017

Candidate Perennial Bioenergy Grasses Have A Higher Albedo Than Annual Row Crops, Jesse N. Miller, Andy Vanloocke, Nuria Gomez-Casanovas, Carl J. Bernacchi

Andy VanLoocke

The production of perennial cellulosic feedstocks for bioenergy presents the potential to diversify regional economies and the national energy supply, while also serving as climate ‘regulators’ due to a number of biogeochemical and biogeophysical differences relative to row crops. Numerous observational and model-based approaches have investigated biogeochemical trade-offs, such as increased carbon sequestration and increased water use, associated with growing cellulosic feedstocks. A less understood aspect is the biogeophysical changes associated with the difference in albedo (a), which could alter the local energy balance and cause local to regional cooling several times larger than that associated with offsetting carbon. Here, …


The Costs Of Photorespiration To Food Production Now And In The Future, Berkley J. Walker, Andy Vanloocke, Carl J. Bernacchi, Donald R. Ort Jan 2017

The Costs Of Photorespiration To Food Production Now And In The Future, Berkley J. Walker, Andy Vanloocke, Carl J. Bernacchi, Donald R. Ort

Andy VanLoocke

Photorespiration is essential for C3 plants but operates at the massive expense of fixed carbon dioxide and energy. Photorespiration is initiated when the initial enzyme of photosynthesis, ribulose-1,5-bisphosphate carboxylase/ oxygenase (Rubisco), reacts with oxygen instead of carbon dioxide and produces a toxic compound that is then recycled by photorespiration. Photorespiration can be modeled at the canopy and regional scales to determine its cost under current and future atmospheres. A regional-scale model reveals that photorespiration currently decreases US soybean and wheat yields by 36% and 20%, respectively, and a 5% decrease in the losses due to photorespiration would be worth approximately …


Research Needs And Challenges In The Few System: Coupling Economic Models With Agronomic, Hydrologic, And Bioenergy Models For Sustainable Food, Energy, And Water Systems, Catherine L. Kling, Raymond W. Arritt, Gray Calhoun, David A. Keiser, John M. Antle, Jeffery G. Arnold, Miguel Carriquiry, Indrajeet Chaubey, Peter Christensen, Baskar Ganapathysubramanian, Philip Gassman, William Gutowski, Thomas W. Hertel, Gerritt Hoogenboom, Elena Irwin, Madhu Khanna, Pierre Mérel, Daniel J. Phaneuf, Andrew Plantinga, Stephen Polasky, Paul Preckel, Sergey Rabotyagov, Ivan Rudik, Silvia Secchi, Aaron Smith, Andrew Vanloocke, Calvin Wolter, Jinhua Zhao, Wendong Zhang Jan 2017

Research Needs And Challenges In The Few System: Coupling Economic Models With Agronomic, Hydrologic, And Bioenergy Models For Sustainable Food, Energy, And Water Systems, Catherine L. Kling, Raymond W. Arritt, Gray Calhoun, David A. Keiser, John M. Antle, Jeffery G. Arnold, Miguel Carriquiry, Indrajeet Chaubey, Peter Christensen, Baskar Ganapathysubramanian, Philip Gassman, William Gutowski, Thomas W. Hertel, Gerritt Hoogenboom, Elena Irwin, Madhu Khanna, Pierre Mérel, Daniel J. Phaneuf, Andrew Plantinga, Stephen Polasky, Paul Preckel, Sergey Rabotyagov, Ivan Rudik, Silvia Secchi, Aaron Smith, Andrew Vanloocke, Calvin Wolter, Jinhua Zhao, Wendong Zhang

Andy VanLoocke

On October 12–13, a workshop funded by the National Science Foundation was held at Iowa State University in Ames, Iowa with a goal of identifying research needs related to coupled economic and biophysical models within the FEW system. Approximately 80 people attended the workshop with about half representing the social sciences (primarily economics) and the rest from the physical and natural sciences. The focus and attendees were chosen so that findings would be particularly relevant to SBE research needs while taking into account the critical connectivity needed between social sciences and other disciplines. We have identified several major gaps in …


Combined And Synergistic Effects Of Climate Change And Urbanization On Water Quality In The Wolf Bay Watershed, Southern Alabama, Ruoyu Wang Jan 2017

Combined And Synergistic Effects Of Climate Change And Urbanization On Water Quality In The Wolf Bay Watershed, Southern Alabama, Ruoyu Wang

Ruoyu Wang

This study investigated potential changes in flow, total suspended solid (TSS) and nutrient (nitrogen and phosphorous) loadings under future climate change, land use/cover (LULC) change and combined change scenarios in the Wolf Bay watershed, southern Alabama, USA. Four Global Circulation Models (GCMs) under three Special Report Emission Scenarios (SRES) of greenhouse gas were used to assess the future climate change (2016–2040). Three projected LULC maps (2030) were employed to reflect different extents of urbanization in future. The individual, combined and synergistic impacts of LULC and climate change on water quantity/quality were analyzed by the Soil and Water Assessment Tool (SWAT). …


Potential State-Level Carbon Revenue Under The Clean Power Plan, Daniel H. Karney Dec 2016

Potential State-Level Carbon Revenue Under The Clean Power Plan, Daniel H. Karney

Daniel H Karney

In 2015, the U.S. EPA issued the Clean Power Plan under which each state can set a mass-based target to meet its assigned electric power sector carbon dioxide emission reductions. If it proceeds, states can design policies to meet those requirements and also raise revenue via a carbon tax or cap-and-trade program with auctioned permits. We calculate each state’s potential revenue and demonstrate its significance. In 13 states, carbon revenue could replace all of corporate tax revenue. In addition, we collect budget projections from six key states to determine if and how carbon revenue can substantially reduce deficits. While such …


Chapter One: Overview Of The Limpopo Basin, Stanley Mubako Dec 2016

Chapter One: Overview Of The Limpopo Basin, Stanley Mubako

Stanley Mubako

No abstract provided.


The Evolution Of A Volunteer Lake Protection Program, Maggie Shannon, Alexa A.E. Junker, Philip J. Nyhus, Cathy R. Bevier, Russell Cole Dec 2016

The Evolution Of A Volunteer Lake Protection Program, Maggie Shannon, Alexa A.E. Junker, Philip J. Nyhus, Cathy R. Bevier, Russell Cole

Philip J. Nyhus

No abstract provided.


15004.Pdf, Marcus C. Randall Dec 2016

15004.Pdf, Marcus C. Randall

Marcus Randall

Increasing human populations and the continual change of the Earth’s climate has meant that food security is becoming an increasingly important issue. One of the main factors contributing to food security is the availability of water for agricultural purposes. Recently, a few models have been proposed for water management problems in agricultural contexts which aim to maximise crop yield (i.e., farm and regional profitability) while minimising the effect that this has on the environment. It is the exploration of the latter that is of the most interest given the above, and hence the subject of this paper. As a refinement …


Where's The Beef: Predicting The Effects Of Climate Change On Cattle Production In Western U.S. Rangelands, Sue Miller, Matthew Clark Reeves, Karen Bagne, John Tanaka Dec 2016

Where's The Beef: Predicting The Effects Of Climate Change On Cattle Production In Western U.S. Rangelands, Sue Miller, Matthew Clark Reeves, Karen Bagne, John Tanaka

Karen Bagne

No abstract provided.