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Full-Text Articles in Physical Sciences and Mathematics

Winter Rye Cover Crop Effect On Corn Seedling Pathogens, Thomas C. Kaspar Jan 2017

Winter Rye Cover Crop Effect On Corn Seedling Pathogens, Thomas C. Kaspar

Leopold Center Completed Grant Reports

Scientists conducted laboratory and field studies to find out what effects cereal rye cover crops might have on corn yield under different contidions and different management tactics.


Crop Diversity Effects On Soil Organic Matter And Nitrate Retention In Surface And Subsoils, Michael J. Castellano Jan 2017

Crop Diversity Effects On Soil Organic Matter And Nitrate Retention In Surface And Subsoils, Michael J. Castellano

Leopold Center Completed Grant Reports

Much of the available soil organic carbon (SOC) is in subsoil, yet few studies have evaluated how crop rotation affects SOC below the plow layer. This project looks at whether crop rotations with greater belowground C inputs would increase SOC stocks by delivering C to subsoil with relatively low SOC levels.


A Smartphone-Based Device For Measuring Soil Organic Matter, Meng Lu Jan 2016

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

Leopold Center Completed Grant Reports

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.


Management And Performance Of Iowa Cover Crops, Jacqueline Comito Jan 2016

Management And Performance Of Iowa Cover Crops, Jacqueline Comito

Leopold Center Completed Grant Reports

Cover crops are valued by a growing number of Midwest corn and soybean growers for their ability to improve soil quality, combat soil compaction, minimize soil erosion, maximize soil nutrient capture, and protect water quality. This project allowed Iowa Learning Farms to collect significant additional data on Iowa cover crop production.


Impacts Of Conventional And Diversified Rotation Systems On Crop Yields, Soil Functions And Environmental Quality: Stage Ii/Year 2, Matthew Z. Liebman, Michael J. Castellano, Ann M. Johanns Jan 2015

Impacts Of Conventional And Diversified Rotation Systems On Crop Yields, Soil Functions And Environmental Quality: Stage Ii/Year 2, Matthew Z. Liebman, Michael J. Castellano, Ann M. Johanns

Leopold Center Completed Grant Reports

Research continued at a long-term crop rotation testing site near Boone, Iowa. In this stage of the trial, attention was directed to estimating soil erosion with the RUSLE2 model, measuring soil nitrogen transformations and nitrogen uptake by corn, and assessing the farm economics of these more varied crop production scenarios using enterprise budgeting techniques.


Enhancing Botanical Composition, Wildlife Habitat And Carbon Sequestration Of Pastures In South Central Iowa Through Soil Disturbance By Mob Grazing Of Beef Cattle, James R. Russell, Harris J. Sellers, Stephen Barnhart, Daniel G. Morrical, Helga Offenburger Jan 2015

Enhancing Botanical Composition, Wildlife Habitat And Carbon Sequestration Of Pastures In South Central Iowa Through Soil Disturbance By Mob Grazing Of Beef Cattle, James R. Russell, Harris J. Sellers, Stephen Barnhart, Daniel G. Morrical, Helga Offenburger

Leopold Center Completed Grant Reports

As Iowa pastures continue to be dominated by cool-season grass species, strategic integration of a single mob-grazing event into pasture management offers a tool to simultaneously increase productivity of pastures and to improve grassland wildlife habitat through increased biodiversity. However, the success of the maneuver depends on climate, soil and landscape.


Understanding Microbial Contributions To Soil Aggregation And Organic Matter Accumulation, Kirsten S. Hofmockel, Elizabeth Marie Bach Jan 2015

Understanding Microbial Contributions To Soil Aggregation And Organic Matter Accumulation, Kirsten S. Hofmockel, Elizabeth Marie Bach

Leopold Center Completed Grant Reports

The goal of the project investigators was to characterize soil bacterial and fungal communities and the rates at which they break down specific plant-derived carbon (C) molecules within soil aggregates in three farming systems.


Investigation Of Bacteria Transport And Resistance Mechanisms And Implications For Water Quality From Confinement Swine And Beef Grazing Production Systems In Iowa, Michelle Soupir, Matt Helmers, Michael L. Thompson, Laura R. Jarboe, Antonio P. Mallarino, Ramesh S. Kanwar Jan 2015

Investigation Of Bacteria Transport And Resistance Mechanisms And Implications For Water Quality From Confinement Swine And Beef Grazing Production Systems In Iowa, Michelle Soupir, Matt Helmers, Michael L. Thompson, Laura R. Jarboe, Antonio P. Mallarino, Ramesh S. Kanwar

Leopold Center Completed Grant Reports

This multi-scale, multi-year study was conducted to begin answering questions related to the fate and transport of nutrients and bacteria from land receiving manure application. Experiments were conducted on tile water drainage at an ISU Research Farm in northeast Iowa.


Soil Health And Productivity In Riparian Grass Buffers: A Re-Evaluation After 13 Years, James W. Raich, Richard Schulz Jan 2015

Soil Health And Productivity In Riparian Grass Buffers: A Re-Evaluation After 13 Years, James W. Raich, Richard Schulz

Leopold Center Completed Grant Reports

In 2001, soil health and productivity were surveyed in riparian grassland buffers adjacent to Bear Creek in northern Story County, Iowa. The investigators resampled these 24 plots in 2014 using the same techniques to see what changes had resulted from the conservation practices applied in the intervening years.


Suitability Of Winter Canola (Brassica Napus) For Enhancing Summer Annual Crop Rotations In Iowa, Mary H. Wiedenhoeft, Rafael A. Martinez-Feria, Thomas C. Kaspar, Keri L. Jacobs Jan 2015

Suitability Of Winter Canola (Brassica Napus) For Enhancing Summer Annual Crop Rotations In Iowa, Mary H. Wiedenhoeft, Rafael A. Martinez-Feria, Thomas C. Kaspar, Keri L. Jacobs

Leopold Center Completed Grant Reports

What are the prospects for winter canola as an alternative crop for Iowa farmers? This project examined the economics and costs/benefits of adding canola as a third crop or a cover crop in rotations.


Linking Soil And Water Quality With Crop Performance Across A Continuum Of Tillage And Management Strategies: Enhancing Sustainability Through Soil-Health-Promoting Practices, Kathleen Delate, Cynthia A. Cambardella, Matt Bakker, Ann M. Johanns Jan 2015

Linking Soil And Water Quality With Crop Performance Across A Continuum Of Tillage And Management Strategies: Enhancing Sustainability Through Soil-Health-Promoting Practices, Kathleen Delate, Cynthia A. Cambardella, Matt Bakker, Ann M. Johanns

Leopold Center Completed Grant Reports

Comparisons across the three Iowa research sites, with histories ranging from three to 17 years, allowed the research team to examine of the effects of crop rotation history (short vs. longer) and system (organic vs. conventional) on weed management, crop productivity, soil quality and soil microbial communities.


Performance Of Cropping Systems Designed To Reduce Nitrate Leaching Into Shallow Municipal Well Aquifers, Robert De Haan, Ronald J. Vos, Matthew Schuiteman, Nelva Huitink, Rebecca Ohrtman, Harlan Kruid, Matthew Van Schouwen Jan 2015

Performance Of Cropping Systems Designed To Reduce Nitrate Leaching Into Shallow Municipal Well Aquifers, Robert De Haan, Ronald J. Vos, Matthew Schuiteman, Nelva Huitink, Rebecca Ohrtman, Harlan Kruid, Matthew Van Schouwen

Leopold Center Completed Grant Reports

This on-farm experiment tested five different cropping systems with the potential to improve nitrate N management in the capture zones of community water supplies in the upper Midwest. Residual soil nitrate N concentrations were determined for each system in order to estimate the likelihood of nitrate N leaching from the system. An economic analysis also was conducted.


Developing Permaculture Techniques For Increased Production And Profit In Sustainable Year-Round Agriculture For Beginning Farmers And Ranchers In Southwest Iowa, Greg Mathis, Michelle Wodtke Franks Jan 2014

Developing Permaculture Techniques For Increased Production And Profit In Sustainable Year-Round Agriculture For Beginning Farmers And Ranchers In Southwest Iowa, Greg Mathis, Michelle Wodtke Franks

Leopold Center Completed Grant Reports

The project participants researched, developed, tested and implemented technologies for year-round growing seasons designed to be viable under the growing conditions in southwest Iowa. High tunnels, alternative crops, vermiculture and collaborative producer groups were among the options tested.


Understanding Soil Organic Matter Change: Modeling Root And Soil Interactions Across Agricultural Landscapes, Cynthia A. Cambardella, Todd A. Ontl, Lisa A. Schulte Moore, Randall K. Kolka Jan 2014

Understanding Soil Organic Matter Change: Modeling Root And Soil Interactions Across Agricultural Landscapes, Cynthia A. Cambardella, Todd A. Ontl, Lisa A. Schulte Moore, Randall K. Kolka

Leopold Center Completed Grant Reports

What are some options for enhancing organic content and carbon storage in soils that have been used in intensive row-crop production? The project looked at bioenergy feedstocks and how they might be employed to improve soil properties.


Crop Availability Of Phosphorus In Beef Manure, Antonio P. Mallarino, Mazhar Ul Haq, Nicolas Dagna Jan 2014

Crop Availability Of Phosphorus In Beef Manure, Antonio P. Mallarino, Mazhar Ul Haq, Nicolas Dagna

Leopold Center Completed Grant Reports

This study provided the first Iowa assessment of the availability of beef cattle manure phosphorus (P) for crops since the early 1970s.


Transitioning To Ecologically Functional Production Systems, Kirsten S. Hofmockel, Lisa A. Schulte Moore, Thomas M. Isenhart, Randall K. Kolka Jan 2014

Transitioning To Ecologically Functional Production Systems, Kirsten S. Hofmockel, Lisa A. Schulte Moore, Thomas M. Isenhart, Randall K. Kolka

Leopold Center Completed Grant Reports

A gap in transitioning to ecologically beneficial farming practices is the lack of understanding of how soils store carbon (C) and nitrogen (N)long term. Farmers need management practices for improving soil quality, increasing both belowground (live roots) and aboveground (live cover) biomass, increasing soil organic matter, and reducing greenhouse gas emissions. This project quantified root productivity, root decomposition, soil microbial dynamics, soil aggregation, and belowground C allocation in annual and perennial biomass cropping systems across multiple landscape positions.


Column Study To Access Bioretention Cell Filter Mixtures For Urban Stormwater Management, Sally D. Logsdon, Pat Sauer Jan 2014

Column Study To Access Bioretention Cell Filter Mixtures For Urban Stormwater Management, Sally D. Logsdon, Pat Sauer

Leopold Center Completed Grant Reports

The study examined several options for material mixtures in bioretention cells to keep water cleaner and cut down on pollution into urban storm sewers.


Comparison Of Biofuel Systems (Cobs) Project: Biomass Energy Conversion And Energy Return On Investment Analyses For 2012 Growing Season, Fernando E. Miguez, Virginia Nichols Jan 2014

Comparison Of Biofuel Systems (Cobs) Project: Biomass Energy Conversion And Energy Return On Investment Analyses For 2012 Growing Season, Fernando E. Miguez, Virginia Nichols

Leopold Center Completed Grant Reports

From 2009-2012 the COBS team used a standard method to estimate carbohydrates in the biomass harvested from the biofuel systems in order to determine the cellulosic yields. This project performed the same analysis for 2012 harvested biomass, and further analyzed biomass from 2009-2012 using a method that is less commonly used due to its expense, but is much more accurate.


Improving Soil Quality By Conserving Insect Pathogens, Aaron J. Gassmann, Erin W. Hodgson, Eric H. Clifton Jan 2013

Improving Soil Quality By Conserving Insect Pathogens, Aaron J. Gassmann, Erin W. Hodgson, Eric H. Clifton

Leopold Center Completed Grant Reports

This study found that organic fields had a greater abundance of naturally occurring entomopathogenic fungi (EPF) than conventional fields in 2011, but that no differences were present in 2012. Conventional producers who used organic fertilizers on their fields had greater abundance of one type of EPF, Metarhizium, in their farm soils than other conventional producers. This suggests that organic practices in corn and soybean fields, and the application of organic fertilizers in conventional fields, could bolster the abundance of naturally occurring EPF.


Exploring The Role Of Multifunctional Agriculture On The Future Of Agriculture And Rural Development, Thanos N. Papanicolaou, Kenneth M. Wacha, Christopher Wilson Jan 2013

Exploring The Role Of Multifunctional Agriculture On The Future Of Agriculture And Rural Development, Thanos N. Papanicolaou, Kenneth M. Wacha, Christopher Wilson

Leopold Center Completed Grant Reports

The goal of this project was better understanding of the interplay between climate shifts and management practices as it affects soil organic matter (SOM) stocks in agricultural fields. Two advanced computer models were used to study this issue. [Keywords: WEPP, CENTURY, CARBON, EROSION]


Drainage Water Quality Impacts Of Current And Future Agricultural Management Practices, Matt Helmers, Ramesh S. Kanwar, Antonio P. Mallarino Jan 2013

Drainage Water Quality Impacts Of Current And Future Agricultural Management Practices, Matt Helmers, Ramesh S. Kanwar, Antonio P. Mallarino

Leopold Center Completed Grant Reports

Researchers examined how crop tillage, rotation or crop residue removal can affect the chemical composition of water draining from farm fields.


Agronomic, Environmental And Economic Performance Of Alternative Biomass Cropping Systems, Lisa A. Schulte Moore, Kenneth J. Moore, Richard B. Hall, Arne Hallam, Matt Helmers Jan 2013

Agronomic, Environmental And Economic Performance Of Alternative Biomass Cropping Systems, Lisa A. Schulte Moore, Kenneth J. Moore, Richard B. Hall, Arne Hallam, Matt Helmers

Leopold Center Completed Grant Reports

If cellulosic biomass is to play a significant role in America's energy future, research needs to be conducted on the optimal production and placement practices. This project looked at a portfolio of biomass cropping systems that might be adopted for Iowa.


Use Of Mob Grazing To Improve Cattle Production, Enhance Legume Establishment And Increase Carbon Sequestration In Iowa Pastures, James R. Russell, Stephen K. Barnhart, Daniel G. Morrical, Harris J. Sellers Jan 2013

Use Of Mob Grazing To Improve Cattle Production, Enhance Legume Establishment And Increase Carbon Sequestration In Iowa Pastures, James R. Russell, Stephen K. Barnhart, Daniel G. Morrical, Harris J. Sellers

Leopold Center Completed Grant Reports

Mob grazing is a variation on rotational grazing that has been proposed to have promise as one of the tactics graziers can use to improve cattle performance and environmental quality. This project looked at whether and how mob grazing could benefit livestock and producer management of their pastures and soil resources.


Impacts To The Land-Water-Human System Of Rural Iowa From High Intensity Continuous Maize Production, C. Lee Burras, Thanos N. Papanicolaou Jan 2013

Impacts To The Land-Water-Human System Of Rural Iowa From High Intensity Continuous Maize Production, C. Lee Burras, Thanos N. Papanicolaou

Leopold Center Completed Grant Reports

Complementary studies from the reference Clear Creek watershed and nine typical watersheds are used to evaluate cropping practices and water quality.


Defining The Grazing Season Of Restored Natural Grasslands, Chris Troendle, Tolif Hunt, Mary H. Wiedenhoeft Jan 2012

Defining The Grazing Season Of Restored Natural Grasslands, Chris Troendle, Tolif Hunt, Mary H. Wiedenhoeft

Leopold Center Completed Grant Reports

Grazing native plants is common in the western United States, but the limited amounts of grazing land in Iowa are dominated by exotic, cool-season grasses and legumes. This study explored the nutritional quality and yields of reconstructed native plant grassland and prairies.


Systems Model And Prototype Development To Capture And Use Rain Water Run-Off From A High Tunnel, Raymond S. Hansen, Linda L. Naeve, Shawn C. Shouse Jan 2012

Systems Model And Prototype Development To Capture And Use Rain Water Run-Off From A High Tunnel, Raymond S. Hansen, Linda L. Naeve, Shawn C. Shouse

Leopold Center Completed Grant Reports

High tunnels offer opportunities for farmers to increase production of seasonal horticultural crops. Because of the tunnel roof design, rainfall poses challenges of drainage, erosion and runoff. This project investigates a system for catching and collecting the rainwater for future use in irrigation.


Increasing Carbon Sequestration Of Working Prairie By Reducing Invasive Species In A Fire And Grazing System, Ryan Harr, David M. Engle, Devan A. Mcgranahan, Jessica J. Veenstra, Aaron Lee Daigh Jan 2012

Increasing Carbon Sequestration Of Working Prairie By Reducing Invasive Species In A Fire And Grazing System, Ryan Harr, David M. Engle, Devan A. Mcgranahan, Jessica J. Veenstra, Aaron Lee Daigh

Leopold Center Completed Grant Reports

The investigators looked at one method for curbing invasive species that limit carbon sequestration potential for tallgrass prairie stands. They also learned that grasslands dominated by either warm-season, cool-season, or mixed stands are likely equal in their carbon sequestration potential.


Evaluating Denitrifying Bioreactors For Edge-Of-Field Nitrogen Management In Iowa's Tile-Drained Landsacpes, Matt Helmers, Alok Bhandari Jan 2012

Evaluating Denitrifying Bioreactors For Edge-Of-Field Nitrogen Management In Iowa's Tile-Drained Landsacpes, Matt Helmers, Alok Bhandari

Leopold Center Completed Grant Reports

Bioreactors show significant potential for removing nitrate from Iowa’s drained fields. The investigators tested the design and management of bioreactors to see what factors can make the bioreactors operate most efficiently, and how that performance compares to other drainage water quality improvement practices.


Soil Moisture Dynamics And Plant Transpiration Under Contrasting Annual-Perennial Cover Types, Matt Helmers, Heidi Asbjornsen, Amy L. Kaleita Jan 2012

Soil Moisture Dynamics And Plant Transpiration Under Contrasting Annual-Perennial Cover Types, Matt Helmers, Heidi Asbjornsen, Amy L. Kaleita

Leopold Center Completed Grant Reports

Soil moisture dynamics are influenced by land cover, thus different land covers would be expected to have different soil moisture behavior. This project tested various land covers and crops to see whether and how moisture was retained or depleted.


Conversion To Perennial Vegetation: Quantifying Soil Water Regime, Aeration, And Implications For Enhancing Soil Resilience To Climate Change, Robert Horton Jr., Thomas J. Sauer, Aaron Lee Daigh Jan 2012

Conversion To Perennial Vegetation: Quantifying Soil Water Regime, Aeration, And Implications For Enhancing Soil Resilience To Climate Change, Robert Horton Jr., Thomas J. Sauer, Aaron Lee Daigh

Leopold Center Completed Grant Reports

Iowa was once awash with native prairie vegetation, and now it is covered with annual crops. This project looked at the different effects these two systems have on Iowa's landscape and natural resource base.