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Hosting The Third Annual Young Women In Agriculture Career And Leadership Seminar, Emma E. Morris, Madyline J. Braught 2018 California Polytechnic State University, San Luis Obispo

Hosting The Third Annual Young Women In Agriculture Career And Leadership Seminar, Emma E. Morris, Madyline J. Braught

Agricultural Education and Communication

Agriculture has traditionally been a male-dominated industry; however, recent years have shown a significant growth in female presence. Women are beginning to take leadership roles both on the farm and within advocacy, lobbying, and business entities in the industry. According to the latest agricultural census data from the United States Department of Agriculture (USDA), in 2012, women farmers controlled seven percent of the nation’s farmland (Census, 2014). Additionally, women held leadership roles in 14 percent of the nation’s two million farms (Census, 2014). This data is several years old, and likely the numbers have grown since the last ...


What’S At Steak? The Political Discourse Of Emissions Intensity And Implications Of Animal Agriculture, Kalyn Simon 2018 The University of San Francisco

What’S At Steak? The Political Discourse Of Emissions Intensity And Implications Of Animal Agriculture, Kalyn Simon

Master's Theses

This thesis analyzes the international discourse of greenhouse gas emissions in relation to livestock production. Specific government ministries, research institutes, and multilateral organizations are framing a new strategy to mitigate emissions by using emissions intensity metrics. Emissions intensity is a ratio comparing emissions produced per unit of animal product as oppose to measuring absolute emissions. This research is acknowledged as a win-win scenario which allows for a reduction of greenhouse gas emissions while continuing production more efficiently. This thesis outlines the emergence of this metric in international discourse and the implications this shift has on the livestock sector globally. Ultimately ...


Ecological And Economic Benefits Of Integrating Sheep Into Viticulture Production, Meredith T. Niles, Rachael Garrett, Drew Walsh 2018 The University of Vermont

Ecological And Economic Benefits Of Integrating Sheep Into Viticulture Production, Meredith T. Niles, Rachael Garrett, Drew Walsh

College of Agriculture and Life Sciences Faculty Publications

The integration of crop and livestock systems has been recognized for its potential to reduce the environmental impacts associated with agriculture and improve farmer livelihoods. However, to date, most research has focused on the integration of cattle into crop and pasture systems. Here we examine the integration of sheep into vineyards and assess farmers’ perceived benefits and costs of the practice. Viticulture expansion has led to significant land use change in recent years and new environmental challenges, particularly with respect to herbicide use. Sheep integration into vineyards offers the potential to utilize the synergies of both systems to reduce external ...


Producing Food, Feed And Energy: How Can Agriculture Do It All?, Emily Heaton, Lisa Schulte-Moore, Matt Helmers, Matt Liebman 2018 Iowa State University

Producing Food, Feed And Energy: How Can Agriculture Do It All?, Emily Heaton, Lisa Schulte-Moore, Matt Helmers, Matt Liebman

Matthew J. Helmers

Sustainable intensification of agricultural systems has been suggested—in addition to reducing waste and changing consumption habits—as a way to increase food, feed, fuel, and fiber security in the 21st century. Here we describe three primary strategies of agricultural intensification—conventional intensification, temporal intensification, and spatial intensification—and how they can be used to manage and integrate food and second-generation (2G) crop portfolios. While each strategy has individual merits, combining them to meet case-specific targets may achieve optimum results. Multiple experiments and examples from Iowa, USA illustrate the potential of combining these approaches for agroecological intensification that can provide ...


Nutrient Reduction Strategy: One Farm, Many Practices, Matthew J. Helmers 2018 Iowa State University

Nutrient Reduction Strategy: One Farm, Many Practices, Matthew J. Helmers

Matthew J. Helmers

With the release of the Iowa Nutrient Reduction Strategy (2013) in early 2013 there has been increased interest in what practices can be utilized by farmers to reduce nutrient export to downstream water bodies. As highlighted by the ISU Extension and Outreach Special Publication 235 (2013) there are many in-field, land use, and edge-of-field practices that have potential to reduce nutrient export. However, to reach the nutrient load reduction goals of 45% on both nitrate-N and phosphorus will require a combination of practices. As a result, there is a need to examine individual fields or small watersheds considering the range ...


Effects Of Nitrogen Application Timing And Source On Nitrate-Nitrogen Leaching And Crop Yields, Ainis Lagzdins, Matthew J. Helmers 2018 Iowa State University

Effects Of Nitrogen Application Timing And Source On Nitrate-Nitrogen Leaching And Crop Yields, Ainis Lagzdins, Matthew J. Helmers

Matthew J. Helmers

Subsurface drainage systems have been intensively installed in the Midwest to enhance agricultural production by removing excess water from naturally poorly drained and somewhat poorly drained agricultural soils. However, despite positive aspects, numerous studies have reported artificial subsurface drainage as one of the primary pathways for nitrate-nitrogen (nitrate-N) loss from agricultural fields to surface water.


Impacts Of 4r Nitrogen Management On Drainage Water Quality, Matthew J. Helmers 2018 Iowa State University

Impacts Of 4r Nitrogen Management On Drainage Water Quality, Matthew J. Helmers

Matthew J. Helmers

Much of the U.S. Corn Belt is characterized by relative flat, poorly-drained areas which with extensive subsurface drainage, have become some of the most valuable and productive agricultural land in the world. However, this is not without consequences. Nitrate-N loss from these systems is of particular concern due to its potential adverse impacts on both public health and ecosystem function. In addition to the potential local impacts on receiving waters in the Corn Belt, nitrogen loads from the region are suspected as a primary contributor to hypoxia in the Gulf of Mexico. For nearly 30 years Iowa State University ...


Drainage Design For Improved Profits And Water Quality, Matthew J. Helmers, Greg Brenneman 2018 Iowa State University

Drainage Design For Improved Profits And Water Quality, Matthew J. Helmers, Greg Brenneman

Matthew J. Helmers

Subsurface drainage systems are an important component of agricultural production systems in many areas of Iowa. However, these drainage systems have been shown to deliver nitrate-N to downstream waterbodies. So, while subsurface drainage is important for crop production we also need to consider the design of these systems to minimize nitrate-N loss. Use of drainage water management in the design and operation of subsurface drainage systems is one potential method to reduce nitrate-N loss.


Modeling The Impacts Of Climate Change On Nitrogen Losses And Crop Yield In A Subsurface Drained Field, Zhaozhi Wang, Qhiming Qi, Lulin Xue, Melissa Bukovsky, Matthew J. Helmers 2018 McGill University

Modeling The Impacts Of Climate Change On Nitrogen Losses And Crop Yield In A Subsurface Drained Field, Zhaozhi Wang, Qhiming Qi, Lulin Xue, Melissa Bukovsky, Matthew J. Helmers

Matthew J. Helmers

The effect of climate change on crop production and nitrate-nitrogen (NO3-N) pollution from subsurface drained fields is of a great concern. Using the calibrated and validated RZWQM2 (coupled with CERES-Maize and CROPGRO in DSSAT), the potential effects of climate change and elevated atmospheric CO2 concentrations (CO2) on tile drainage volume, NO3-N losses, and crop production were assessed integrally for the first time for a corn-soybean rotation cropping system near Gilmore City, Iowa. RZWQM2 simulated results under 20-year observed historical weather data (1990–2009) and ambient CO2 were compared to those under 20-year projected future meteorological data (2045–2064) and elevated ...


Electrical Stimulation For Enhanced Denitrification In Woodchip Bioreactors: Opportunities And Challenges, J. Y. Law, Michelle L. Soupir, D. Raj Raman, T. B. Moorman, Say K. Ong 2018 Iowa State University

Electrical Stimulation For Enhanced Denitrification In Woodchip Bioreactors: Opportunities And Challenges, J. Y. Law, Michelle L. Soupir, D. Raj Raman, T. B. Moorman, Say K. Ong

D. Raj Raman

Woodchip bioreactors are being implemented for the removal of nitrates in groundwater and tile water drainage. However, low nitrate removals in denitrifying woodchip bioreactors have been observed for short hydraulic retention time (HRT) and low water temperature (°C). One potential approach to improve woodchip bioreactor performance is to provide an alternative and readily available electron source to the denitrifying microorganisms through electrical stimulation. Previous work has demonstrated the capability of bio-electrochemical reactors (BER) to remove a variety of water contaminants, including nitrate, in the presence of a soluble carbon source. The objective of this study was to evaluate the denitrification ...


Performance Of Chicks Subjected To Thermal Challenge, Patrícia Ferreira Ponciano Ferraz, Tadayuki Yanagi Junior, Renato Ribeiro de Lima, Gabriel Araújo e Silva Ferraz, Hongwei Xin 2018 Universidade Federal de Lavras (Ufla)

Performance Of Chicks Subjected To Thermal Challenge, Patrícia Ferreira Ponciano Ferraz, Tadayuki Yanagi Junior, Renato Ribeiro De Lima, Gabriel Araújo E Silva Ferraz, Hongwei Xin

Hongwei Xin

The objective of this work was to evaluate the effect of thermal challenge at different intensities and durations on the production responses of 3 to 21-day-old broiler chickens. Two hundred and ten Cobb chicks were subjected to dry-bulb temperatures (tdb) of 27, 30, 33, or 36°C for the duration of 0, 1, 2, 3, or 4 days from the second day of life onwards. The experiment was carried out in four identical environmentally-controlled wind tunnels. Data on body mass (BM), feed intake (FI), and water intake (WI), all in grams, were monitored daily; and body weight gain (BWG), in ...


Sow Lying Behaviors Before, During And After Farrowing, F. Lao, T. M. Brown-Brandl, G. Teng, Kai Liu, Hongwei Xin 2018 China Agricultural University

Sow Lying Behaviors Before, During And After Farrowing, F. Lao, T. M. Brown-Brandl, G. Teng, Kai Liu, Hongwei Xin

Hongwei Xin

Piglet pre-weaning mortality remains a considerable challenge for the swine industry, representing one of the key areas where animal well-being and economical interest coincide. Sows and piglets carry out a complex series of behaviors during the farrowing/lactation period. These behaviors during the first few days after parturition are extremely important for piglet survival, and they can be greatly impacted by the farrowing system, environment, and/or management. The risk of sow crushing is much greater for piglets when the sow changes her postures. Limited studies have investigated the effects of environment on sow’s posture changes or basic understanding ...


Heat And Moisture Productionof Modern Swine, Tami M. Brown-Brandl, Morgan D. Hayes, Hongwei Xin, John A. Nienaber, Hong Li, Roger A. Eigenberg, John P. Stinn, Timothy Shepherd 2018 United States Department of Agriculture

Heat And Moisture Productionof Modern Swine, Tami M. Brown-Brandl, Morgan D. Hayes, Hongwei Xin, John A. Nienaber, Hong Li, Roger A. Eigenberg, John P. Stinn, Timothy Shepherd

Hongwei Xin

The total heat and moisture production (THP and MP) values of pigs that are currently published in ASHRAE standards are from data collected in either the 1970s (nursery piglets) or the 1950s (growing-finishing pigs). These series of studies, conducted to systematically update the THP and MPstandards, includes a series of four indirect calorimeter studies (nursery, growing-finishing gilts, and finishing barrows), and six facility-level studies (nursery, growing, early finishing, late finishing, gestating gilts, and farrowing sows and litters). The studies were completed at various temperatures from thermal neutral to hot conditions, demonstrating the trends that HP and feed intake decreased while ...


Free Chlorine Loss During Spraying Of Membraneless Acidic Electrolyzed Water And Its Antimicrobial Effect On Airborne Bacteria From Poultry House, Yang Zhao, Hongwei Xin, Deiling Zhao, Weichao Zheng, Wei Tian, He Ma, Kai Liu, Hui Hu, Tong Wang, Michelle L. Soupir 2018 Iowa State University

Free Chlorine Loss During Spraying Of Membraneless Acidic Electrolyzed Water And Its Antimicrobial Effect On Airborne Bacteria From Poultry House, Yang Zhao, Hongwei Xin, Deiling Zhao, Weichao Zheng, Wei Tian, He Ma, Kai Liu, Hui Hu, Tong Wang, Michelle L. Soupir

Hongwei Xin

Spray-application of membraneless acidic electrolyzed water (MLAEW) is a novel technique for disinfection in livestock houses. This study investigated the loss of free chlorine (FC – the major germicidal component in MLAEW) over distance during spraying, as affected by air temperature and initial FC concentration. The anti-microbial effect of MLAEW on airborne bacteria from an aviary laying-hen house was examined. materials and methods. MLAEW was prepared at two FC concentrations: app. 15 and 60 mg L -1 , and sprayed at three air temperatures (18, 25, 32 °C). The original MLAEW solution and MLAEW aerosols collected at 0, 25, and 50 cm ...


Does A Nir System Provide Low-Cost Alternative To On-Farm Feed And Forage Testing? A Techno-Economic Analysis, Sai K. Ramaswamy, Kurt A. Rosentrater, Gretchen A. Mosher 2018 Iowa State University

Does A Nir System Provide Low-Cost Alternative To On-Farm Feed And Forage Testing? A Techno-Economic Analysis, Sai K. Ramaswamy, Kurt A. Rosentrater, Gretchen A. Mosher

Gretchen A. Mosher

Improperly balanced diet not only impacts the quality of animal products but also the quantity of profits of a livestock operation. Typically, the nutrient and chemical content of feed ingredients and forages are determined using well-established wet chemistry tests. However, these tests can be expensive and time-consuming. Moreover, the increasing use of distiller’s by-products which are known to have large variations in chemical and nutrient content warrants a real-time on-farm feed and forage testing system. Near Infra-Red (NIR) spectroscopy systems have been documented as a quick and effective on-site testing tool across several industries. While NIR systems are being ...


Modeling Distillers Dried Grains With Solubles (Ddgs) Mass Flow Rate As Affected By Drying And Storage Conditions, Rumela Bhadra, Kurt A. Rosentrater, K. Muthukumarappan 2018 United States Department of Agriculture

Modeling Distillers Dried Grains With Solubles (Ddgs) Mass Flow Rate As Affected By Drying And Storage Conditions, Rumela Bhadra, Kurt A. Rosentrater, K. Muthukumarappan

Kurt A. Rosentrater

Ethanol production in 2015 was over 15 million gallons in the United States, and it is projected to increase in the next few years to meet market demands. With the continued growth in the ethanol industry, there has been enormous expansion in distillers grains production. Because the local market for distillers dried grains with solubles (DDGS) is often saturated, it is essential to transport DDGS long distances, across the United States and to international markets. Caking and agglomeration of DDGS particles in hoppers and other storage structures are typical during transportation. The current study deals with DDGS prepared by combining ...


Postharvest Practices And Mycotoxins Of Maize In Three Agro-Ecological Zones Of Tanzania, R. A. Suleiman, Kurt A. Rosentrater, B. Chove 2018 Sokoine University of Agriculture

Postharvest Practices And Mycotoxins Of Maize In Three Agro-Ecological Zones Of Tanzania, R. A. Suleiman, Kurt A. Rosentrater, B. Chove

Kurt A. Rosentrater

Maize is a major cereal crop in Tanzania and it is grown in diverse agro-ecological zones. Like other sub-Saharan countries, postharvest losses of maize during storage in Tanzania remain significantly high, especially for smallholder farmers. Unpredictable weather and poor postharvest practice contribute to rapid deterioration of grain and mold contamination, and subsequent production of mycotoxins. The purpose of this study was to assess the postharvest practices, awareness and knowledge of mycotoxin contamination in maize grain in three agro-ecological zones (Eastern, Central, and Northern) of Tanzania between November 2015 and February 2016. A survey using semi-structured questionnaires was administered to farmers ...


Economic And Environmental Impact Analysis Of Vegetable Production In Bamboo Polyhouse Vs Galvanized Iron Pipe Polyhouse, Harishchandra Jadhav, Kurt A. Rosentrater 2018 Iowa State University

Economic And Environmental Impact Analysis Of Vegetable Production In Bamboo Polyhouse Vs Galvanized Iron Pipe Polyhouse, Harishchandra Jadhav, Kurt A. Rosentrater

Kurt A. Rosentrater

In the attempt to reduce the capital cost of a metal polyhouse, the bamboo polyhouse was designed and constructed for vegetable production suitable for the hot and humid climate. The economic analysis (EA) of the bamboo polyhosue was performed for tomato production and results were compared with the similar but hypothetical galvanized iron (GI) polyhosue. Further, the environmental impact analysis (EIA) was carried out on the both bamboo and GI polyhouses limited to the construction of the polyhouses. The initial/construction cost of bamboo polyhouse was found about 72% of the GI polyhouse. The BC ratios of GI and bamboo ...


Does A Nir System Provide Low-Cost Alternative To On-Farm Feed And Forage Testing? A Techno-Economic Analysis, Sai K. Ramaswamy, Kurt A. Rosentrater, Gretchen A. Mosher 2018 Iowa State University

Does A Nir System Provide Low-Cost Alternative To On-Farm Feed And Forage Testing? A Techno-Economic Analysis, Sai K. Ramaswamy, Kurt A. Rosentrater, Gretchen A. Mosher

Kurt A. Rosentrater

Improperly balanced diet not only impacts the quality of animal products but also the quantity of profits of a livestock operation. Typically, the nutrient and chemical content of feed ingredients and forages are determined using well-established wet chemistry tests. However, these tests can be expensive and time-consuming. Moreover, the increasing use of distiller’s by-products which are known to have large variations in chemical and nutrient content warrants a real-time on-farm feed and forage testing system. Near Infra-Red (NIR) spectroscopy systems have been documented as a quick and effective on-site testing tool across several industries. While NIR systems are being ...


Electrical Stimulation For Enhanced Denitrification In Woodchip Bioreactors: Opportunities And Challenges, J. Y. Law, Michelle L. Soupir, D. Raj Raman, T. B. Moorman, Say K. Ong 2018 Iowa State University

Electrical Stimulation For Enhanced Denitrification In Woodchip Bioreactors: Opportunities And Challenges, J. Y. Law, Michelle L. Soupir, D. Raj Raman, T. B. Moorman, Say K. Ong

Michelle L. Soupir

Woodchip bioreactors are being implemented for the removal of nitrates in groundwater and tile water drainage. However, low nitrate removals in denitrifying woodchip bioreactors have been observed for short hydraulic retention time (HRT) and low water temperature (°C). One potential approach to improve woodchip bioreactor performance is to provide an alternative and readily available electron source to the denitrifying microorganisms through electrical stimulation. Previous work has demonstrated the capability of bio-electrochemical reactors (BER) to remove a variety of water contaminants, including nitrate, in the presence of a soluble carbon source. The objective of this study was to evaluate the denitrification ...


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