Agronomy and Crop Sciences Commons^™

Investigating The Toxicity And Accumulation Of 2,4-Dichlorophenoxyacetic Acid (2,4-D) And Glyphosate In Eisenia Fetida, Caitlin Lazurick, Nicole Lidzbarski, Rachel Owings, Jeff Brotherton, Edna Steele

Journal of the South Carolina Academy of Science

Glyphosate, the main ingredient in Roundup^®, is the most widely used herbicide in the world. It is also used in combination with another effective herbicide, 2,4-D, in the formulation called Enlist Duo^®. The EPA approved the use of Enlist Duo^® on certain crops including those genetically modified to be resistant to both herbicides. The predicted significant increase in the use of these herbicides raised concerns from the general public because both compounds have been classified as possibly or probably carcinogenic. Since herbicides are applied directly to vegetation, the safety of organisms that come in contact …

Climate Change And Food Systems: Assessing Impacts And Opportunities, Meredith T. Niles, Richie Ahuja, Jimena M. Esquivel, Nelson Mango, Mil Duncan, Martin Heller, Cristina Tirado

College of Agriculture and Life Sciences Faculty Publications

No abstract provided.

Agricultural Responses To Climate Change: A Study Of Adaptive Farming Methods In Kizanda Village, Bailey Smith-Helman

Independent Study Project (ISP) Collection

Agriculture is vital to the economic and social systems in Tanzania, composing 30% of the country’s GDP as well as 80% of employment (FAO, 2014). Despite agriculture’s important role, it remains one of the most vulnerable sectors to climate change. Current trends project global average temperature to increase by 0.8-2.6 degrees Celsius, leaving farmers to face changes in rainfall, soil quality, and new pests and diseases (IPCC, 2007). Farmers will be forced to adapt to the changing climate if they are to sustain their livelihoods and the Tanzanian economy. For these reasons, it is important to understand the types of …

A Laboratory-Scale Study On The Production Of High-Value Products From Broiler Litter Involving Solid-State Anaerobic Digestion And Mushroom Cultivation, Joe Barrett Carter Iii

Graduate Theses and Dissertations

There is a need to investigate alternate uses and treatments of broiler litter that lessen environmental impacts and decrease costs associated with its disposal. Anaerobic digestion is a biological process in which organic material is converted to a renewable fuel source. However, the substrate for anaerobic digestion often requires some form or pretreatment. Certain types of fungus have been investigated as a pretreatment for anaerobic digestion, one of which is Pleurotis ostreatus or the oyster mushroom, which also produces an edible fruiting body. Thus, this study was performed to investigate the use of broiler litter for oyster mushroom cultivation and …

A Smartphone-Based Device For Measuring Soil Organic Matter, Meng Lu

Meng Lu

The project evaluated the potential of utilizing a smartphone-based system for the in-field analysis of Soil Organic Matter. Although it demonstrated that the performance of the smartphone-based spectrometer can be comparable to commercial spectrometers, the results suggest that it is challenging to identify the spectral “signatures” of the SOM due to the morphology and moisture variation of soil samples.

Winter Grazing Management, Stephen K. Barnhart, James R. Russell, Douglas L. Karlen, Michael J. Tidman

Douglas L Karlen

Why winter grazing? Beef cow herd and sheep flock records show that winter feeding costs are livestock producers' single largest production expense. Managing through winter weather while keeping feeding costs low is an essential part of maintaining a profitable operation. Iowa's climate generally allows forage growth only during a 7-to-8 month period. Extending the grazing of this forage--even an extra 3 or 4 weeks in late autumn and winter--is an economical way to maintain or increase livestock profitability. Some producers extend the grazing season by using stockpiled forage, whereas others use crop residue, and many combine the use of stockpiled …

Winter Rye Cover Crop Biomass Production, Degradation, And N Recycling, J. L. Pantoja, J. E. Sawyer, D. W. Barker

John E. Sawyer

Winter rye (Secale cereale L.) as a cover crop can take up residual inorganic N between annual row crops and therefore be used to help reduce NO3 -–N loss from fields and movement to water systems. However, does the rye N uptake affect N recycling to soil and add to plant available N? The rye carbon:nitrogen (C:N) ratio could also influence N recycling. The objectives of this study were to evaluate rye biomass degradation and N recycling after spring rye termination in a no-till corn (Zea mays L.) - soybean [Glycine max. (L.) Merr.] rotation. A two year experiment (2010-2011) …

A Web Based Real Time Nitrogen Leaching Calculator, Saeideh Samani, Babak Samani, Haishun Yang

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

While nitrogen (N) is an essential nutrient for corn, its leaching to ground water is an serious environmental issue and a hazard to public health. N leaching is closely linked to weather factors, especially rainfall. Prediction of N leaching in cropping systems is critical to improvement of crop management and reduction of N leaching. The objective of this project is to develop a web app that predicts in real-time mode N leaching across Nebraska using real-time weather data.

We are in the processing of developing the web app and expect a prototype to be running in 2017 cropping season. Field …

Modeling Gross Primary Production Of Midwest Maize And Soybean Croplands With Satellite And Gridded Weather Data, Gunnar Malek-Madani

Department of Geography: Dissertations, Theses, and Student Research

The gross primary production (GPP) metric is useful in determining trends in the terrestrial carbon cycle. Models that determine GPP utilizing the light use efficiency (LUE) approach in conjunction with biophysical parameters that account for local weather conditions and crop specific factors are beneficial in that they combine the accuracy of the biophysical model with the versatility of the LUE model. One such model developed using in situ data was adapted to operate with remote sensing derived leaf area index (LAI) data and gridded weather datasets. The model, known as the Light Use Efficiency GPP Model (EGM), uses a four …

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

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

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

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

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

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 …

Effects Of Post Eviction Resettlement On Land-Use And Cover Change In Uganda’S Oil Exploration Areas, Joseph Ssekandi, John Mburu, Oliver Wasonga, Laban Macopiyo, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Evaluation of the changes in land use and land cover change (LULCC) in respect to oil exploration across the Albertine region in Uganda has been focused around the exploration areas and protected areas, with no attention to the potential impacts of evictees’ activities on resettled areas. This study used LANDSAT images to analyze the land use and land cover changes (LULCC) among the period before eviction (2002 and 2005) at the climax of eviction and resettlements (2005-2011), and during the post-resettlement period (2011-2015) to quantify the impacts of resettlements on the environment. LANDSAT images were processed using ERDAS IMAGINE software …

Carbon Stocks In Shade Coffee: Strategies For Enhancing Carbon Storage In Smallholder Systems In Jinotega, Nicaragua, Vanessa Katheryn Kichline

Bard Center for Environmental Policy

Climate change has recently shifted focus to adaptation and mitigation strategies in coffee production. Shade coffee systems, already widely recognized for their contribution to biodiversity and soil conservation, are now drawing attention for their role in carbon storage. Researchers have generally assumed that high carbon storage must come at the expense of reduced crop yields, implying that farmers must choose between sustainability and profit. This study uses field inventories of 70 farms in Jinotega, Nicaragua to estimate this tradeoff in smallholder shade coffee systems. Field inventories were used to develop three typologies representing different shade management strategies in use in …