Browsing by Subject "Agriculture"
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Item Advancing Remote Sensing For Soybean Aphid (Hemiptera: Aphididae) Management In Soybean(2019-07) Marston, ZacharySoybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is the most economically important insect pest of soybean, Glycine max (L.) Merrill (Fabales: Fabaceae), in the north-central United States. Current management recommendations for soybean aphid include frequent scouting of soybean fields and application of foliar insecticides when soybean aphid populations exceed an economic threshold of 250 aphids per plant. The scouting process for soybean aphid is time consuming, expensive, and also fails to thoroughly assess populations across the entire field. Because of these drawbacks, 84% of soybean farmers want to reduce scouting efforts. In 2015, it was determined that soybean aphid-induced stress had a significant effect on red-edge and near-infrared (NIR) reflectance of soybean canopies, offering the potential to use remote sensing for soybean aphid scouting. Utilizing remote sensing for soybean aphid scouting may decrease human effort, increase spatial coverage, and ultimately increase the adoption of recommended management practices. However, it was unknown whether soybean aphid-induced stress could be detected from aerial platforms, whether these reflectance data of aphid-induced stress could be classified into treatment groups, and how confounding factors might affect classification results. My first chapter determined that soybean aphid-induced stress could be detected from an unmanned aerial vehicle (UAV) equipped with a multispectral sensor. Findings indicated that NIR reflectance decreased as aphid populations increased in both caged and open-field experiments. Chapter 2 evaluated ground-based hyperspectral samples and determined that soybean reflectance samples that were above the economic threshold of 250 aphids per plant could be classified with over 86% accuracy using linear support vector machine classification. Chapter 3 further evaluated ground-based hyperspectral samples in the presence of the confounding disease, soybean sudden death syndrome (SDS) caused by the fungal pathogen Fusarium virguliforme O’Donnell and T. Aoki (Hypocraeles: Nectriaceae). Findings indicated that when using linear support vector machines, it was difficult to differentiate between healthy and diseased samples; however, including the diseased group in the classification model decreased false positives for soybean aphid-induced stress. Overall, these findings advance the use of remote sensing for soybean aphid management and provide the first documentation of spectral classification of soybean aphid into threshold-based groups.Item Agricultural Education in America(1909-05) Macdonald, WilliamItem Agricultural Preservation Precedent Studies(Minneapolis: Center for Urban and Regional Affairs, 2009) Schweser, GregItem Agriculture of the Hidatsa Indians an Indian Interpretation(1917-11) Wilson, Gilbert LivingstoneItem American black bears: Strategies for living in a fragmented, agricultural landscape(2014-08) Ditmer, Mark AllanThe American black bear (Ursus americanus) is a forest-dwelling species, but also an ecological opportunist. Few studies have investigated ecological and landscape requirements for this species in highly-fragmented habitats. Northwestern Minnesota is particularly well suited for such a study because it marks the historical western edge of black bears in eastern U.S.. This area is a patchwork of forest (<20% coverage) and agricultural lands, with contiguous forests eastward and agriculture westward. My dissertation, spurred by this intriguing increase and expansion of bears at the edge of their range, focuses broadly on two interrelated fundamental ecological questions: (1) how do bears respond to fragmentation of forested habitat, and (2) how is the edge of a bear's geographic range delimited? Results from stable isotope analysis illustrated how a small portion of the landscape used for corn and sunflower production (1-4% annually) was a major portion of some bears' diets. We found the degree of crop consumption varied with natural forage availability, demographics, size and health, space use patterns and landscape fragmentation surrounding the individual. Captive bear food preference trials revealed that male bears were much more apt to try novel, high-calorie foods, but females learned to do so after more exposure. My analysis utilizing advanced biologger technology of bears' heart rates revealed that bears were not stressed when foraging in cropfields or in small patches of forest but when crossing open fields without foods, their heart rates were typically faster than expected for their rate of travel, indicating a stress response. I found bears in this area have the largest home ranges ever recorded for the species, so I used short-term (weekly) home ranges to estimate how landscape, habitat type, caloric availability and demographics affected the amount of area a bear used at different times of year. I used results from this analysis to produce regional maps of bear habitat quality under varying natural and anthropogenic food conditions, showing the probable geographic limit of this range. It appears that for bears to expand much farther west they would need to cross a large expanse of unsuitable habitat or slacken habitat requirements.Item Assessing Site Suitability for Land Application of Biosolids in St. Louis, Carlton, and Douglas Counties(University of Minnesota Duluth, 1996) Host, George E; Polzer, Philip L.The effective implementation of a biosolids land application program requires a suitable base of potential sites within a reasonable transportation distance. The objective of this study was to determine the acreage of potential agricultural and forested sites within Carlton, Douglas, and selected areas of St. Louis County. Suitability was determined using land use information in conjunction with soils data in a Geographic Information System (GIS) environment. This study was done in cooperation with the St. Louis County Minnesota Extension Service.Item The Breeding and Development of Milking Strains of Shorthorn Cattle(1910-06) Baker, George JacobItem Breeding Bird Communities Across an Upland Disturbance Gradient in the Western Lake Superior Region(2007) Miller, Christina; Niemi, Gerald J; Hanowski, JoAnn M; Regal, Ronald RThe coastal region of western Lake Superior to examine relationships to human land use. Eighty-four species were detected and 50 were abundant enough to be included in data analysis. Monotonic quadratic regression models were constructed for these 50 species by using species counts as the dependent variable and the proportion of human conversion of the landscape (residential, agriculture, and commercial/industrial land uses) within each study area as the independent variable. Twenty-seven bird species had significant regressions (P < 0.05), 18 of which generally avoided areas developed by humans and 9 of which were attracted to development. De-trended correspondence analysis using counts of these 27 bird species was used to investigate multivariate, community responses to development. The first DCA axis was interpreted as a gradient from urban avoiding to urban exploiting bird species and was strongly correlated with land cover variables related to human development. Our results advance the idea that breeding bird communities can be used as indicators of ecological condition and can diagnose potential causes for changes in these conditions. Further, our study points out the usefulness of bird monitoring data in regional planning efforts that incorporate goals for maintaining native biological diversity.Item The Carbon Dioxide Diffusion Ratio in Doughs as an Index of Flour Strength(1921-06) Weigley, MildredItem Channel, Riparian and Catchment Features as Predictors of Wood Abundance in Low Gradient, Agricultural Streams(University of Minnesota Duluth, 2002) Johnson, Lucinda B; Host, George E; Richards, CarlWood is an important component of small to medium streams in forested regions, but has been little studied in agricultural areas. Although wood habitat has been shown to be an important factor controlling macroinvertebrate biodiversity in agricultural regions of the Midwestern U.S., there is little information on how much wood is available and what factors control its abundance and distribution. The goals of this study were to: 1) characterize the abundance, size, and distribution of wood in low gradient streams in a predominantly agricultural region, and 2) quantify the relative influence of reach- and catchment-scale factors on the abundance and distribution of wood in these streams. Standing stocks of wood were quantified in 49 stream reaches in the Saginaw Basin of central Michigan, USA. An array of stream channel, riparian zone, and catchment features were quantified. Multiple regressions were conducted to predict standing stocks from explanatory variables at three spatial scales. Features at the local scale (e.g., bank-full width, % open canopy) had a large influence on the density and size of accumulations, and a moderate influence on wood abundance. In contrast, riparian and catchment features including riparian vegetation type, link number, % urban land use in the catchment, and topographic heterogeneity exerted greater control over wood abundance and the mean size of wood accumulations. The differences in the factors predicting wood standing stocks versus accumulation density are probably related to the presence of structures that entrain wood into accumulations. In contrast, wood standing stocks reflect current and past land use practices, as well as underlying processes (e.g., hydrologic regime) controlled by landforms. Patterns in wood standing stock and distribution differ from those observed in high gradient regions, and low gradient streams in forested regions. This has important implications for ecosystem processes and management of headwater streams in agricultural regions.Item A Classification of Field Beans, Phaseolus(1921-06) Steinmetz, Ferdinand H.Item Consolidation, Competition, and Antitrust Law: A Changing Landscape for Minnesota Farmers(2024-05-01) Keliher, MatthewMuch of the research on farming and agricultural market concentration focuses on the importance of quantitative elements such as price, access to markets or capital, or concentration ratios. And while these quantitative measurements are critical for understanding the impact consolidation has on consumers and producers within the broader agricultural industry, it only represents one aspect. This qualitative study aims to capture the perspectives of Minnesota farmers to explore how consolidated agriculture markets impact farmers’ communities and livelihoods. Comparing their perspectives with the current literature regarding market concentration in agriculture and food distribution, this study aims to illuminate the views of independent farmers that are subject to the control of dominant firms that abuse their market power. Semi-structured interviews with Minnesota farmers highlight key elements of the reviewed literature and demonstrate connections between challenges faced by farmers with economic indicators such high costs of farming inputs, the limitations of quality rural healthcare, and the burden placed on farming communities through restrictions on repairing agricultural equipment. A key theme throughout the interviews revealed that many farmers view consolidated industries as systems of control. Control over how they can farm, how they can care for and feed their livestock, how they can repair their machinery, where they can sell their produce and for how much. These systems of control are often hailed as “efficiencies” by consolidated corporate power. But for farmers, these systems of control represent an end to two things farmers and all citizens value most: creativity and liberty.Item Constructed wetland used to treat nitrate pollution generated from agricultural tile drainage waters in Southern Minnesota(2014-09) Ross, Nikol BaileyNitrate molecules are highly soluble in water and are bioavailable to plants. These properties are why excess nitrates in water are one of the main causes of hypoxia in the northern Gulf of Mexico. Over 90% of these nitrates originate from non-point sources such as agricultural fields. In fields with tile drainage systems nitrates have a swift passageway from field to surface waters. This study focuses on one Midwestern farm field located in southern Minnesota, along Elm Creek, a Blue Earth tributary. Tile drainage water from this field discharges into Elm Creek at a concentration averaging 23.0 mg/L NO3 as NO3-N. During the spring of 2013 a three celled treatment wetland was constructed adjacent to Elm Creek. The tile drainage system was re-routed to discharge into the constructed wetland. In the 2013 field season water volumes were monitored continuously and water samples were taken from the inlet, the wetland cells, and the outlet on a periodic basis. During the season the volume of tile drainage water that reached Elm Creek as surface water was reduced by 82%. The concentration of NO3-N in the water was not significantly reduced. However, the total load of NO3-N that reached Elm Creek as surface water was reduced by 262 to 332 pounds (14.4-18.2 lbs./acre). Most of the water that did not reach Elm Creek infiltrated into the subsurface soils and still contained NO3-N. Using the MPCA's (2013) estimates of groundwater denitrification for agroecoregions, a 45% reduction rate was applied at this location. When the 45% reduction rate is applied to the subsurface load it is estimated that 113.0 to 134 lbs. (6.21-7.36 lbs./acre) of NO3-N were removed from the infiltrated water. Thus a total of 124 to 172 lbs. (6.81-9.45 lbs./acre) of NO3-N were removed from the entire wetland system which accounts for 37.1-43.3% of the NO3-N.A concurrent laboratory experiment was set up in 2013 to test the effectiveness of different soils and vegetation at removing nitrate loads. Wetland mesocosm experiments were set up with soil collected from the field site and the design vegetation used in the field cells. Three vegetated mesocosm tanks were planted in Coland soils with Switchgrass (Panicum virgatum), Fringed Sedge (Carex crinita) and a tank with an equal mix of Dark Green Bulrush (Scirpus atrovirens), Panicum virgatum, and Carex crinita. The results showed that the mixed vegetation regime and the Panicum virgatum had significantly greater nitrate removal than the control (Coland bare soil). The mixed vegetation mesocosm had the highest amount of nitrate removal after 10 days at 34.9%. There was no significant difference in the nitrate removal rates in the soils tested.Item Correlation Studies in Wheat(1921-06) Shelton, James PeelItem The Cost of Apple Production in Thirty-five Representative Orchards in Minnesota(1919-06) Koppen, Walter J.Item COVID-19 impacts on agrifood supply chain businesses in the United States(2022-11-28) Peterson, Hikaru, H; DiGiacomo, Gigi; Court, Christa, D; Oliveira, Gustavo; Zhang, Li; hhp@umn.edu; Peterson, Hikaru, H; USDA AFRI Project "Lessons from COVID-19: Positioning Regional Food Supply Chains for Future Pandemics, Natural Disasters and Human-Made Crisis" TeamA validated agricultural disaster assessment instrument was adapted to survey five segments of the agrifood supply chain: agricultural production, food manufacturing, grocery wholesaling, food and beverage retailing, and restaurants. The survey was fielded online from February to April 2021 to distribution lists compiled by the team to businesses in three study regions: California, Florida, and Minnesota-Wisconsin. This is the first coordinated assessment of the COVID-19 pandemic impacts on agrifood businesses that have been administered across multiple segments of the supply chain in multiple regions.Item Denitrification in Agricultural Surface Waters: Quantifying the Effect of Environmental Parameters and Hydrologic Connectivity on Nitrate Uptake and Microbial Communities(2017-10) Tomasek, AbigailThe development of synthetic fertilizer has led to increases in crop yields and allowed for global population growth over the past century. However, this increase in available nitrogen has greatly altered the global nitrogen cycle, including increased nitrate loading to surface water and groundwater in the Midwestern United States, with negative effects on human health and aquatic ecosystems. Therefore, there is a need for effective management strategies and an understanding of the mechanisms for nitrate transport and uptake. Denitrification, the microbiological reduction of nitrate to nitrogen gas, can be viewed as a net sink for reactive nitrogen in aquatic systems. Small areas, termed hot spots, and short time periods, termed hot moments, frequently account for a large portion of denitrification. This research focuses on identifying the environmental parameters and hydrologic regimes that promote denitrification, along with determining how parameters, denitrification rates, and microbiological communities are related at multiple temporal and spatial scales. At the finest scale, a recirculating laboratory flume was used to determine the effect of turbulence and organic carbon on denitrification rates and the microbial community. An outdoor experimental stream and flow-through basin in the Outdoor StreamLab at the St. Anthony Falls Laboratory (SAFL) were used to determine the effect of short-term inundation and periodic inundation on denitrification. At the largest scale, water and sediment samples were collected over two years from a field site in an agricultural watershed in Southern Minnesota. The objectives of this research were to: (1) determine how turbulence and organic carbon affect denitrification, (2) investigate how inundation and hydrologic connectivity leads to the formation of denitrification hot spots and hot moments, (3) quantify and correlate the driving environmental parameters of microbial denitrification and the differences in these relationships for in-channel and riparian locations in an agricultural watershed, (4) develop and evaluate functional relationships between environmental parameters and denitrification rates, and (5) identify how denitrifying gene abundances, denitrification rates, and environmental parameters are related across a hydrologic gradient from channels to riparian areas.Item Differentiating Characters and their Inheritance in Marquis, Preston, and Bluestem Spring Wheats(1919-06) Kurtzweil, CarlItem DISSOLVED PHOSPHORUS DYNAMICS AND MANAGEMENT WITHIN THE AGRICULTURAL LANDSCAPE(2022-05) Bender, LauraAgricultural phosphorus loss was identified as a water quality priority within the Minnesota Nutrient Reduction strategy identifying a 45% yield reduction goal. Implementation plans call for total phosphorus (TP) reduction with traditional management strategies designed for erosion control and particulate nutrient removal, leaving the dissolved, or bioavailable, forms of phosphorus un-accounted for. Substantial yield increases in agricultural tributaries over recent decades highlight the need for dissolved reactive phosphorus (DRP) management, with some sources documenting over 50% DRP contributions to TP loads in Minnesota. DRP, hydrology, management and site-specific factors were investigated at two field research sites in southern Minnesota, with additional data harnessed from the Minnesota Discovery Farms Program. Data was used to assess the impacts of various site and management factors including cover crops, riparian buffers, edge-of-field wetlands, tillage category, fertilizer application and soil properties on phosphorus loads from farm fields and edge-of-field best management practice (BMPs) uptake. Four project objectives were addressed; 1.) to quantify and characterize current and target DRP yields from Southern Minnesota agricultural fields, 2.) to quantify the influence of local field and management conditions on DRP yields, 3.) to assess the effectiveness or inefficacy of common management practices for phosphorus and nitrogen removal, and 4.) to explore novel management strategies for DRP yield reductions including treatment trains, microbial soil amendment and plant harvest. Methodology included hydrologic monitoring, soil assessment, edge of field nutrient concentration analysis and measurement of phosphorus in vegetation to track phosphorus movement through the soil, water and plant components of agroecosystems. Current DRP loss rates from agricultural fields were quantified at 0.49 kg ha-1, with a target DRP yield of 0.27 kg ha-1 to achieve a 45% phosphorus reduction. To meet target yields, project results demonstrated the importance of both surface and subsurface DRP loss pathways, legacy phosphorus monitoring and management and the need for coordinated edge of-field and in-field management strategies. Significant conditions driving drain tile DRP concentrations included manure application rate, number of tillage passes and soil test phosphorus (STP). Significant conditions driving surface DRP concentrations included cumulative manure and fertilizer application rate and STP. STP accumulation was driven most significantly by manure application rate, number of tillage passes, organic matter content, clay content, soil pH and cover crop implementation. Cover crops, which were placed into the context of an agricultural treatment train, were found to reduce subsurface DRP concentrations by 63% and annual yields by .07 kg ha-1 through reduced constituent mobilization at higher flows but also to contribute to increased STP. Crop use efficiency, fertilizer application and soil phosphorus draw down where also associated as part of a mass balance to further correlate management action to DRP yields. Research findings will help to inform agricultural management for DRP removal strategies necessary for setting and meeting realistic nutrient reduction and water quality goals.Item Duluth Farmers' Market Survey and Business Plan(2006) UMD Labovitz School of Business and EconomicsThe Duluth Market Gardeners' Association worked with the Labovitz School’s research bureau to describe the history of the business, marketing financials, business operations, and an executive summary for the business plan. Information from the survey analysis was brought in to guide the marketing plan and to focus expectations for future fund raising and building projects. This is a economics and marketing survey with little insight into land use, water or natural resources.