Long Term, Continuous Temperature Monitoring of a Simple Anaerobic Digester and Open Manure Storage Pond in Eastern South Dakota

A two-cell manure storage system with a cover on the first cell was constructed in the late summer of 2009 in Eastern South Dakota. The covered cell acts as a simple anaerobic digester. Continuous temperature monitoring for 8 months shows the winter effluent temperature equilibrated to around 6°C, and that the effluent temperature trend lagged the ambient temperature trend by a month. Manure composition was also analyzed and was found to be relatively steady throughout the system. Volatile solids were the only component that dropped appreciably across the treatment cell, with an observed maximum of 50% reduction

A dynamic model of ammonia production within grow-finish swine barns

Ammonia is a nuisance gas in many swine barns. The overall objective of this research project was to model ammonia formation and transmission processes in a grower-finisher swine barn, by first modelling the ammonia production and emission from urine puddles on the floor surface and the ammonia emission from the slurry pit, and then incorporating these emission rates in a dynamic model that separates the room and slurry pit headspace as two separate, but linked, control volumes. A series of studies were conducted to gather more information about the processes affecting the ammonia emission rate from the floor surface and the slurry that were later included in the overall room model developed. The model was then used to investigate ammonia reducing techniques and technologies based on the understanding of ammonia production and transmission incorporated in the model. The first step in modelling the ammonia emission rate from the floor surface was to determine the frequency of urinations by grower-finisher pigs. Male and female pigs were observed three times during their finishing phase to determine their urination frequency over the course of a day. The average measured urination frequency was 0.62 ± 0.11 urinations pig-1 h-1. A sinusoidal dromedary model was developed to describe the daily variation in urination frequency for male and female pigs between 51 and 78 kg.In order for the deposited urinations on the floor surface to emit ammonia, the urea in the urine must first be converted to ammonia and the urease enzyme catalyzes this reaction. Two methods, a fixed-time-point method using the indophenol assay for ammonium-nitrogen analysis and a continuous method using the coupled enzyme assay, were used to measure enzyme activity at the floor surface of a swine barn and were compared to reported urease activity levels in the literature. Using both methods, there appeared to be an ammonia-producing site on the floor surface or within the collected samples that made accurate measurements of urease activity impossible. A review of urease activity levels in the literature from dairy-cow houses suggest that urease activity will be lowest following floor-cleaning and increase quickly following fouling of the floor surface. Based on the literature review, a urease activity value of 5 g NH¬3 m-2 h-1 was suggested for use in ammonia emission modelling of fouled floor surfaces in swine barns until better measurements become available. The ammonia emissions from 36 simulated urine puddles under a variety of temperature, air velocity and initial urea concentration conditions were measured in a bench-scale experimental set-up. The measurements were used to calibrate and validate a dynamic, mechanistic, urine puddle emission model that considered the processes of evaporation, urea conversion, change in liquid concentration and puddle pH in order to simulate the amount of ammonia emitted from a puddle. Based on the correlation coefficients (R) between measured and simulated values for water volume (R=0.99), total ammoniacal nitrogen concentration (R=0.90), and total emission (R=1.00), along with five other statistical tests for each simulated variable, the model was deemed accurate. The measurements and simulations in this experiment showed the impact of puddle pH, urease activity and changing environmental conditions on the average puddle emission rate. Puddle emission continued to occur as long as there was still water. The impact of different slurry compositions on the ammonia emission rate from slurry pits was tested in another bench-scale experimental set-up with emission chambers. The emission chamber concentration data collected was used to calibrate and validate a developed slurry emission model. The collected slurry samples were concentrated mixtures of urine and feces from individually-housed animals fed different diets. An empirical equation was developed to express the amount of total ammoniacal nitrogen in the slurry that was in the form of ammonia (f) and thus volatile to the surroundings. Based on the empirical equation, the simulated value of f was between 0.03 and 0.08 and did not show the sensitivity to slurry pH that has been reported by other authors. The slurry emission model with the empirical equation for f was validated with ammonia emission measurements from eight different slurry samples and simulated hourly concentration measurements within 17% and five-day average concentration measurements within 3%. Further testing was recommended to ensure the model developed for concentrated manure in this study was applicable to the more dilute slurry found in swine barns. Using the information gained in the previous experiments, a mechanistic model describing the dynamic ammonia concentration in the room and in the slurry channel headspace of grower-finisher swine barns, as well as the ammonia emitted to the surrounding environment was developed. Data was collected from two grower-finisher rooms to use as input data to the model and for calibration and validation purposes. The model calibration procedure determined that the amount of emissions originating from the slurry for the simulated room conditions was generally less than 5% of the total room emissions, the air exchange rate through the slatted floor was approximately 4% of the room ventilation rate, and that in the first two weeks of animal activity in a room the urease activity at the floor surface will increase. The model was validated using separate data from that used in the calibration process. The model simulated hourly room concentration levels within 2.2 ppm and 3-day average concentration levels within 1.6 ppm. The model simulations were more accurate for one room that was fed a typical grower-finisher diet compared to another room fed an experimental diet with lower protein content and sugar-beet pulp inclusion. The dynamic model was tested for its sensitivity to various input factors in terms of the floor emission rate, slurry emission rate and total emission rate. An interesting aspect of the simulations was that increases in either floor or surface emission rate were compensated to a small extent by decreases in the other emission rate as a result of a reduced concentration gradient for mass transfer. The ammonia emission rate from the floor was most sensitive to changes in urease activity, fouled floor area and puddle area. The ammonia emission rate from slurry was most sensitive to changes in slurry pH. The impact of input variables on the total emission rate was dependant on the simulated proportion of the total ammonia emission coming from either the floor surface or slurry channel. Three ammonia reduction techniques were tested and evaluated on their impact to the total ammonia emission rate from a room compared to a given set of control conditions.The work in this thesis highlighted the importance of ammonia emission from the floor surface. The proportion of ammonia originating from the slurry and from the floor surface respectively will vary on the specific conditions within the barn, and will impact the effect of any ammonia mitigation technique that is investigated or used

Improving Ammonia Emission Modeling and Inventories by Data Mining and Intelligent Interpretation of the National Air Emission Monitoring Study Database

Ammonia emission is one of the greatest environmental concerns in sustainable agriculture development. Several limitations and fundamental problems associated with the current agricultural ammonia emission modeling and emission inventories have been identified. They were associated with a significant disconnection between field monitoring data and knowledge about the data. Comprehensive field measurement datasets have not been fully exploited for scientific research and emission regulations. This situation can be considerably improved if the currently available data are better interpreted and the new knowledge is applied to update ammonia emission modeling techniques. The world’s largest agricultural air quality monitoring database with more than 2.4 billion data points has recently been created by the United States’ National Air Emission Monitoring Study. New approaches of data mining and intelligent interpretation of the database are planned to uncover new knowledge and to answer a series of questions that have been raised. The expected results of this new research idea include enhanced fundamental understanding of ammonia emissions from animal agriculture and improved accuracy and scope in regional and national ammonia emission inventories

Integrating Food Policy with Growing Health and Wellness Concerns: An Analytical Literature Review of the Issues Affecting Government, Industry, and Civil Society

Over the past few years, there has been growing global interest in the link between food and health. This paper provides a review of some of the recent literature describing these linkages. The first section provides an overview of findings that link the consumption of fruits and vegetables, meat, eggs, whole-grains, alcohol, sugar, dairy, fish, pulses, soy, and nuts to coronary heart disease, cancer, stroke, and diabetes. The authors then summarize various international and domestic non-government organizations' views about these issues. The third section centres on the food industry and its responses to growing health concerns. The fourth section is an overview of public policy relating to food and health, including the use of food policy to change consumption behaviour and address obesity. This section also includes a discussion of the relevance of policies designed to discourage smoking to the current debate on obesity. The Conclusion highlights ways in which Canadian food policy can be adapted in order to better promote health and wellness.Food Consumption/Nutrition/Food Safety, Health Economics and Policy, Agribusiness,

Improving Ammonia Emission Modeling and Inventories by Data Mining and Intelligent Interpretation of the National Air Emission Monitoring Study Database

Ammonia emission is one of the greatest environmental concerns in sustainable agriculture development. Several limitations and fundamental problems associated with the current agricultural ammonia emission modeling and emission inventories have been identified. They were associated with a significant disconnection between field monitoring data and knowledge about the data. Comprehensive field measurement datasets have not been fully exploited for scientific research and emission regulations. This situation can be considerably improved if the currently available data are better interpreted and the new knowledge is applied to update ammonia emission modeling techniques. The world\u27s largest agricultural air quality monitoring database with more than 2.4 billion data points has recently been created by the United States\u27 National Air Emission Monitoring Study. New approaches of data mining and intelligent interpretation of the database are planned to uncover new knowledge and to answer a series of questions that have been raised. The expected results of this new research idea include enhanced fundamental understanding of ammonia emissions from animal agriculture and improved accuracy and scope in regional and national ammonia emission inventories

Engineering the Future: A Workshop for High School Teachers

The framework guiding the development of Next Generation Science Standards (NGSS) identifies eight science and engineering principles essential for all students to learn. The Engineering the Future workshop, offered by South Dakota State University (SDSU) in the summer of 2012, focused on helping teachers better understand those principles and how to employ them effectively in their classrooms. Each day of the week-long workshop, teachers participated in a variety of engineering-related activities, accessed low and high-end instrumentation, took tours of engineering-related facilities in the region, and developed lesson plans to incorporate what they learned into their science classrooms. We used pre- and postworkshop surveys to assess the participants’ understanding and attitudes regarding science and engineering. Results of the survey showed participants had a narrow view of engineering prior to the workshop but by the end of the workshop, they were more aware of the nature of engineering, the various types of engineering, and they better understood how they could incorporate engineering principles into their current curriculum

An environmental assessment of cattle manure and urea fertilizer treatments for corn production in the northern Great Plains

Nitrogen (N), phosphorus (P), and carbon (C) emissions from livestock systems have become important regional, national, and international concerns. Our objective was to use process-level simulation to explore differences among manure and inorganic fertilizer treatments in a corn production system used to feed finishing cattle in the Northern Great Plains region of the U.S. Our analysis included model assessment, simulation to compare treatments under recent climate, and comparisons using projected midcentury climate. The Integrated Farm System Model was evaluated in representing the performance and nutrient losses of corn production using cattle manure without bedding, manure with bedding, urea, and no fertilization treatments. Two-year field experiments conducted near Clay Center, Nebraska; Brookings, South Dakota; and Fargo, North Dakota provided observed emission data following these treatments. Means of simulated emission rates of methane, ammonia, and nitrous oxide were generally similar to those observed from field-applied manure or urea fertilizer. Simulation of corn production systems over 25 years of recent climate showed greater soluble P runoff with use of feedlot and bedded manure compared to use of inorganic fertilizers, but life-cycle fossil energy use and greenhouse gas emission were decreased. Compared to feedlot manure, application of bedded pack manure generally increased N and P losses in corn production by retaining more N in manure removed from a bedded housing facility and through increased runoff because a large portion of the stover was removed from the cornfield for use as bedding material. Simulation of these treatments using projected midcentury climate indicated a trend toward a small increase in simulated grain production in the Dakotas and a small decrease for irrigated corn in Nebraska. Climate differences affected the three production systems similarly, so production and environmental impact differences among the fertilization systems under future climate were similar to those obtained under recent climate

Relevant Information Sources in the Vast and Complex Manure Nutrient Management Network

To understand and delineate pathways for effective information transfer among professional audiences in manure nutrient management, we deployed a survey, taken by 964 professionals, addressing workforce demographics, tasks performed, and information source relevance. Findings indicate that education of industry and the public is a widespread effort among the multiple organizations represented. The average relevance of different types of information sources was consistent across various organization types. Compared to mass media sources, information sources that were technical and individual- or group-oriented in nature were more relevant to respondents representing all organization types and levels of knowledge. Opportunities exist for translation of the findings presented to other networks of entities working toward common objectives

Socio-Economic and Governance Conditions Corresponding to Change in Animal Agriculture: South Dakota Case Study

Understanding sustainable livestock production requires consideration of both qualitative and quantitative factors in a temporal and/or spatial frame. This study adapted Qualitative Comparative Analysis (QCA) to relate conditions of social, economic, and governance factors to changes in livestock inventory across several counties and over time. This paper presents an approach that (1) identified factors with the potential to relate to a change in livestock inventory and (2) analyzed commonalities within these factors related to changes spatially and temporally. This paper illustrates the approach and results when applied to five counties in eastern South Dakota. The specific response variables were periods of increasing, no change, or decreasing beef cattle, dairy cattle, and swine inventories in the specific counties for five-year census periods between 1992 and 2017. In the spatial analysis of counties, stable beef inventories and decreasing dairy inventories related to counties with increasing gross domestic products. The presence of specific social communities related to increases in county swine inventories. In the temporal analysis of census periods, local governance and economic factors, particularly market price influences, were more prevalent. Swine inventory showed a stronger link to cash crop markets than to livestock markets, whereas cattle market price increases associated with stable inventories for all animal types. Local governance tools had mixed effects for the different animal types across space and time. The factors and analysis results are context-specific. However, the process considers the various socio-economic processes in livestock production and community development applicable to agricultural sustainability questions in the Midwest and beyond