Browsing by Subject "Soil"
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Item 17 Soils: Settling, Stealing, Stirring(2022-08) Linqduist, Stephanie A.Within 17 Soils: Settling, Stealing, Stirring I invite the viewer, especially those non-native like myself, to look at soil with new eyes. Using 9 soils from Mni Sota Makoce/ Minnesota and 6 soils from the Gorama Mɛnde chiefdom in Sierra Leone, I paint images of connection to earth. Through the lens of analog photography and digital manipulation, my frame wanders from the farming village in Mɔndema to my own backyard and public gardens in the Twin Cities. Within this text is a collectively written soil index, selected images, and essays describing my internal approach towards creating this installation of paintings and light bench.Item Agricultural Wetland Restoration: The Role of Sediment Removal, Hydroperiod and Time on Restoration Outcomes(2021-06) Winikoff, SarahRestoring agricultural wetlands to remediate nutrient runoff, decrease flood risk, and improve wildlife habitat are areas of growing interest. One restoration strategy that may improve species diversity, enhance water retention, and decrease nutrient availability is the removal of accumulated eroded sediment from agricultural wetlands prior to restoration. In this work, we the measured physical and chemical characteristics of soils, characterized plant communities, and examined water column nutrient availability and denitrification potential in 54 restored agricultural wetlands in west central Minnesota. In half of the wetlands hydrologic function was restored by removing and plugging drainage tile and ditches, while hydrology was restored in the remaining basins following sediment removal (Excavation treatment), increasing basin depth by an average 30 cm. Excavation primarily influenced the plant community, by delaying the establishment of two invasive emergent macrophytes, hybrid cattail (Typha x glauca) and reed canary grass (Phalaris arundinacea), but the affect only lasted for 6 years. Contrary to expectations, soil properties, water column dissolved nutrients, and denitrification potential were all primarily influenced by hydroperiod – the number of consecutive days with standing water. Wetlands with longer hydroperiods had less bioavailable P in soils, lower dissolved N and P concentrations, and lower denitrification potential. We also found evidence that vegetation likely plays an important role in dissolved nutrient dynamics over time. Our results suggest that excavation may be an important tool in wetland restoration but its influence was lost as wetlands aged in the absence of invasive species management. Moreover, nitrogen and phosphorus dynamics were almost universally controlled by hydroperiod, with tradeoffs between nitrogen removal and phosphorus remineralization.Item Biochar as a sorbent for naturally occurring and synthetic agricultural chemicals(2018-06) Hall, KathleenThe idea of adding biochar to soil to sequester carbon and improve fertility has soared in popularity over the past few decades; however, a strong scientific understanding of this material and its environmental effects is still lacking. This body of work explores biochar's interactions with chemicals, both naturally occurring (i.e., allelochemicals) and anthropogenically applied (i.e., herbicides), and sheds light on the mechanisms involved and our ability to predict and optimize its sorptive behavior. The first chapter investigates how the feedstock material from which a biochar is produced impacts its sorptive behavior toward allelochemicals. Mixing different feedstocks, such as pine chips and poultry litter, is thought to be a way to create “designer biochars” that combine the beneficial properties of each feedstock. However, results from this study revealed that mixing feedstock materials did not have predictable effects on organic compound sorption. The second chapter begins to evaluate biochar-chemical interactions in soil to better understand realistic applications of biochar as a sorbent. Here, the leaching potentials of six different herbicides were assessed in vulnerable Hawaiian soils, and biochar was tested as a tool to reduce the transport of the most mobile herbicide, aminocyclopyrachlor. It was found that none of the four biochar amendments tested significantly altered the leaching potential of aminocyclopyrachlor in these soils based on fate and transport models. In the third chapter, the focus shifts more towards understanding the mechanisms of biochar-herbicide interactions. Here we specifically looked at glyphosate, the world’s most widely used herbicide, and found that biochar macroporosity and specific surface functionality influenced glyphosate sorption. Additionally, pre-pyrolysis addition of Fe and Cu had no significant effect on sorption. Results from this work also demonstrated the reversibility of glyphosate sorption on biochar in the presence of phosphate, suggesting similar binding mechanisms and potential interferences from phosphate fertilizers. The fourth chapter continues to investigate the sorption mechanisms responsible for the observed biochar-herbicide interactions and simultaneously assesses our ability to optimize biochars for sorption through activation treatments. It was found that activation of a low-temperature biochar by hydrogen peroxide can improve the removal of organic acid herbicides from aqueous solution, but was of little value in optimizing the removal of non-ionizable herbicides. The improved removal efficiency was attributed to pH effects and charge-based interactions with biochar. Collectively, the research presented in this dissertation highlights the variability of biochar's sorptive behavior and illustrates the challenges in predicting this behavior, particularly when feedstocks are combined. While the sorptive applications in soil initially appear limited, there is potential to improve the sorption capacity of these materials through activation, and more targeted improvements will be possible once sorption mechanisms are better understood.Item Characteristics of Selected Horizons from 16 Soil Series in Minnesota(Minnesota Agricultural Experiment Station, 1970-11) Pluth, D.J.; Adams, R.S. Jr.; Rust, R.H.; Peterson, J.R.This report compiles and summarizes some chemical, physical, and mineralogical properties of samples collected in 1965 for studies on pesticide adsorption and desorption by soils. The 16 soil series sampled generally represent soils of agricultural importance and occur extensively in Minnesota. They include a wide range of soil properties found in agricultural soils in the state. The actual sampling site for each soil series met two criteria: it was close to a modal or typical profile and it had a known 5-year history of pesticide use. Supplementary profile descriptions and laboratory data were available prior to sampling from the Soil Conservation Service or the Bureau of Public Roads for a few of the soil series at their sampling sites.Item Comparison and Methods For Estimating Soil Surface Area(2016-01-14) Chi, BrianSoil Surface Area is important when analyzing land management and agriculture practices. Indirect methods of measuring Soil Surface Area are usually done through clay content. For this research I have compared both the Hydrometer method and Laser Particle Size Analyzer (LPSA) method as a means of analyzing soil texture. I then compared the Clay Content given from the Hydrometer and compared it to the Soil Surface Area data from the Brunauer–Emmett–Teller (BET) method. I found out that the LPSA didn't correlate to the Hydrometer method when analyzing soil texture. This means we can't use it as a reliable means of soil texture analysis. There needs to be further research on this subject before proving of it. The clay content given from the Hydrometer soil texture data correlated well with the BET SSA data. This means that the clay content does correspond to the soil surface area, this means that it can be used as a cheaper method to predict soil surface area. This discovery will be useful for future research within the soil science field.Item Consumers' willingness-to-pay for perennial grass conversion to renewable energy in South-Central Minnesota.(2010-08) Pham, Matthew VanThere has been an interest in growing perennial grass on marginal croplands to provide electricity and recreational services in the Madelia, Minnesota region. Policymakers and landowners want to know if it is economically feasible for farmers to convert row crops, such as corn and soybean, to perennial crops since the conversion will only take place only under the right economic conditions. A questionnaire was completed by 725 Carver, Dakota, and Scott county residents, which gave a response rate of 29 percent, to determine how much they would be willing-to-pay (WTP) to utilize the recreational services at a converted site. Using the contingent valuation and hypothetical trip cost models, some support exists for the perennial grass conversion. However, 52 percent would not be willing-to-pay for the conversion, and 64 percent would not visit the converted land. Using the estimated WTP amount from the contingent valuation model, calculations were performed to determine the total benefits a farmer would receive from converting to a perennial grass crop. In most cases, a farmer growing corn and soybean crops would not convert due to the higher revenue earned from growing corn and soybean, with rotation. However, the farmer will convert to perennial crops if unlimited credit stacking, or payments for multiple ecological benefits, are allowed.Item Extractability of carbon, nitrogen, and phosphorus in United States grasslands(2015-02) Thompson, Seth K.Tracking how energy flows within and across ecosystems is imperative for understanding interactions among biogeochemical cycles. Aquatic ecosystem metabolism is inextricably linked to the terrestrial landscape, with many lakes getting over 50% of their carbon from terrestrial sources. Nonetheless, there are few large scale measurements of actual carbon export from terrestrial ecosystems. Instead, scientists have relied on a mass balance approach to estimate the quantity of carbon coming into aquatic ecosystems based on estimates of riverine carbon delivery to the ocean. This approach has left many unanswered questions related to the controls on terrestrial organic matter export, both in terms of quantity and quality. Here I used Water Extractable Organic Carbon (WEOC) to estimate potential terrestrial carbon export and to understand the mechanisms controlling these exports. Results from extractions performed at 19 grassland sites across the United States suggested that 1-5% of their total soil carbon was in the water extractable organic carbon pool. In addition, this work suggested that soils selectively retained nitrogen and phosphorus, with less organic nutrient export relative to organic carbon to aquatic ecosystems. These data demonstrated the usefulness of measuring water extractable organic matter (WEOM) on broad spatial scales to gain a better understanding of both the amounts and types of organic matter that are available for export from terrestrial ecosystems.Item The fate of antibiotic resistance genes during treatment and disposal of residual municipal wastewater solids(2013-12) Burch, Tucker RamseyThe development of resistance to antibiotics among pathogens is a global public health dilemma with significant consequences for the length and quality of human life. As a result, the bacterial antibiotic resistance genes (ARGs) that confer resistance are increasingly regarded as environmental contaminants. A significant body of knowledge has been generated that catalogues the occurrence of ARGs in numerous environmental reservoirs, among which residual municipal wastewater solids are one of the largest. Only a handful of studies, however, make the critical paradigm shift to considering treatment technologies and management strategies intended to reduce the quantities of ARGs in those reservoirs. The objective of the work presented here was to evaluate various treatment technologies and management strategies for reducing the quantity of ARGs discharged from the municipal wastewater treatment process during treatment and disposal of residual solids. Aerobic digestion, air drying, and hyperthermophilic (¡Ý 60¡ãC) anaerobic digestion were evaluated for their abilities to reduce ARG quantities in residual municipal wastewater solids using laboratory-scale treatment units. The technologies were compared among each other and to mesophilic (40¡ãC) and thermophilic (56¡ãC) anaerobic digestion on the basis of the kinetics of ARG removal from residual solids. While all technologies were effective, hyperthermophilic anaerobic digestion tended to exhibit the fastest kinetics. In addition, class 1 integrons were identified as a candidate design gene, and batch or semi-batch flow configurations were demonstrated to be a potential means of optimizing the removal of ARGs from residual solids during aerobic digestion, thermophilic anaerobic digestion, and hyperthermophilic anaerobic digestion. The fate of ARGs in soil following simulated disposal was also investigated by applying treated residual solids from full-scale treatment facilities and from numerous laboratory-scale treatment units to soil microcosms. ARGs from residual solids treated at typical full-scale treatment facilities persisted in soil at high concentrations for relatively long periods of time, with half-lives on the order of months. Alkali stabilization, thermophilic anaerobic digestion, hyperthermophilic anaerobic digestion, and pasteurization, however, caused drastic decreases in ARG quantities in soil within one month. The results presented here can be used to optimize and design the residual municipal wastewater solids treatment and disposal process to remove ARGs.Item Fertilizer Guidelines for Agronomic Crops in Minnesota(University of Minnesota Extension, 2023-07-27) Kaiser, Daniel EItem Fungi in Antarctica: a circumpolar study of biodiversity in soils and historic structures.(2010-07) Arenz, Brett EvanAntarctica is the most remote and isolated continent on Earth and is generally thought to have low biodiversity due to environmental extremes. These relatively simple ecosystems are important to study because they can be used to improve understanding of more complex systems world-wide that are difficult to analyze directly. The isolation of the continent, extreme environmental conditions and the lack of functional redundancy in ecosystem processes make it particularly vulnerable to human disturbance and require improved understanding. The results of this research support the hypothesis that fungal abundance and distribution are generally linked to the presence of primary producers and their effect on carbon and nitrogen quantities in the soil. Experiments introducing sterile plant-derived nutrient sources (wood and cellulose) to soils resulted in increased fungal abundance up to three to four orders of magnitude greater than background soil levels. This suggests that the extremes of the Antarctic environment (low moisture, high salinity, cold temperatures) are primarily affecting fungi by limiting the distribution of flora and direct effects on the fungi are relatively less important as these indigenous soil fungi appear well adapted to Antarctic environment. A survey of fungal diversity near historic sites and areas where materials were introduced to the Antarctic Peninsula reveals a very similar composition to those affecting historic sites on Ross Island. The fungi found in greatest abundance were species of Geomyces and Cadophora. These two genera also formed a large percentage of the fungal colonization of buried nutrient substrates. The frequent reports of these fungi from many areas in Antarctica and the large diversity of species found indicates they are well adapted to their environment and suggests they are indigenous to Antarctica. The dominance of these fungi on human-introduced material indicates direct human influences may be of more benefit to generalist indigenous decomposer fungi which are pre-adapted to the environmental extremes rather than human-introduced fungi which may be better adapted to utilizing these substrates but not well adapted to the Antarctic environment. It also supports the hypothesis of indigenous Antarctic fungi being primarily limited by nutrient availability.Item An holistic approach to modelling the removal of particles and chemicals from natural waters.(2010-05) Potoka, Stephanie MarieProduction of food and fiber for use by people is a vital necessity, yet a highly controversial one. The rise of modern agriculture has greatly increased the yield of crops, but the benefit of increased production has come at the cost of environmental degradation. The intensified use of land has led to both increased soil erosion and increased use of pesticides and fertilizers. If mobilized off the agricultural field, soil and chemicals have the potential to contaminate both surface water and groundwater. There are many methods used to mathematically model the movement and fate of eroded soil and mobilized chemicals. These methods cover a wide range of spatial and temporal scales, ranging from simulating one storm event on one field to simulating a watershed over the course of years. It would, therefore, be helpful to have a common method of measuring soil and chemical removal in various water bodies. For this reason, a new expression is introduced, a half-life of removal. This term represents a standard quantification of the residence time of a chemical or particle in water. The half-life measure is versatile and universal. Not only can it be calculated for any particle or chemical in any aquatic environment for any removal mechanism, but it can also be compared against any other chemical or particle half-life for many different situations. The versatility of the half-life measure is illustrated by using a variety of equations and models to compute the half-life of removal for soil particles and chemicals in three water compartments: surface water, groundwater, and run-off. The particles considered are size 300 #22;m and smaller while the chemicals have Kd values ranging from 10-1 to 107 L/kg. The half-lives obtained for the ranges of particles and chemicals in the three water compartments are compared. The universal nature of the half-life measure is demonstrated by this comparison of particle and chemical half-lives in the three compartments.Item Influences of management and the environment on phosphorus leaching in corn-soybean systems in Minnesota(2018-08) Leverich, LeannaPhosphorus is an essential nutrient in corn and soybean systems for maximizing yields and profits in Minnesota. The over-application of P fertilizer can lead to the impairment of freshwater ecosystems throughout the Midwest and United States. Excess P in freshwater can ultimately lead to eutrophication and detrimental species population shifts. To help mitigate such pollution here in Minnesota, research was completed to identify the risk of P loss to the environment through leaching. The objectives of this research were to 1) Evaluate the potential for water soluble P loss from top soils (0-15 cm) across a range of initial soil test phosphorus (STP) levels and timings of leaching events after fertilizer application (denoted as “leachtimes”); 2) Determine the effect of soil type, soil properties, initial STP level, various leaching intensities, and P fertilizer source on P leaching losses; 3) Assess the predictability of P loss through leaching using routine soil tests, leaching intensity, soil properties and sorption estimates. Six sites throughout the state of Minnesota under long-term P management were used for this study. Intact soil columns were taken from all sites to identify the risk of P leaching from various Minnesota soils with varying chemical and physical properties. Columns were leached at 10x field capacity to balance for various water holding capacities among sites. The influences of soil test P (STP), soil type, and timing of a leaching event after fertilization were evaluated for effects of P leaching as P leachate concentration, P load, and percent of P fertilizer leached. In addition, a second set of intact columns were collected from three of the six sites for further evaluation of leaching intensity and P fertilizer source on P leaching potential. Leaching intensity was applied at three rates 200, 400, 600 mL to evaluate effects on P leaching. Liquid P fertilizer, dry P fertilizer, manure, and liquid P fertilizer with the addition of AVAIL® were evaluated for influences on P leaching. Results from this study indicated P leaching is a substantial loss pathway with greater losses occurring at higher STP levels. Leachtime also significantly affected P leaching losses, with immediate leach events after fertilizer applications leading to losses up to 33 percent. Volume of the leaching event was found to be the driver of P load, as P concentrations remain consistent with volume applied, and concentrations were not diluted. Phosphorus fertilizer source also significantly impacted P leaching losses, with dry fertilizers leaching significantly more P than liquid or manure sources. Results indicated soil hydrology may be substantially influencing leaching, with preferential pathways leading to greater P leaching losses. Relating P leaching losses to soil test measures was moderately successful; however, relationships were not strong enough to lead to P leaching loss predictions. Relationships were strongest among the environmental soil tests, Water extractable P (WEP) and BioAvailable P (BAP), and the Olsen P (OP) routine soil test. Further research is necessary to fully understand P leaching especially at deeper depths.Item Influences of riparian buffers and soil variability on the hydrology of seasonal wetlands in Northern Minnesota(2012-12) Tersteeg, Daniel PatrickThe objectives of this research were to determine what effect buffering seasonal ponds following harvest of adjacent upland forest has on pond hydrology; as well as to investigate soil morphology associated with these ponds. Study areas were established in north central Minnesota in 2000 and buffer treatments assigned randomly to ponds included: control, uncut buffer, partial buffer, and clearcut buffer. One year of pre-harvest and five years of post-harvest data was collected to examine hydrologic characteristics and distinguish any differences between buffer treatments. Soil texture and hydraulic conductivity was analyzed to determine the influence on formation of seasonal ponds on the landscape. The results suggest that it is possible to manipulate hydrologic characteristics in seasonal ponds following upland harvest based on the type of buffer treatment. The presence of both Bt horizon formation and lithologic discontinuity suggests seasonal pond formation can be attributed to both geogenic and pedogenic processes.Item Low-Vibration Methods of Soil Compaction for Urban Utility Projects: Phase 2(1995-04) Sterling, Raymond L.This report presents the findings of the second phase of an exploratory project to assess the potential of nonvibratory methods of compaction for utility-related compaction needs. Proposed refinements and additions to existing compaction procedures are based on the use of an alternating flooding and vacuum procedure introduced through a pipe or series of pipes embedded in the soil. This process had been demonstrated in early Phase I laboratory tests to give better results than flooding alone for granular soils. Phase II laboratory and field tests produced compaction results ranging from an acceptable level of compaction to an unacceptable level. The flood/vacuum method appeared to work best in well-graded granular materials including some, but not an excessive amount of, fine particles. The cycle times for flooding and vacuum removal of the water appeared to be too long for practical use. The flood/vacuum technique by itself, or without reasonable levels of static compaction, does not appear to be a viable technique for field use. It appears that results from the technique could be significantly approved by adding mechanical disturbance of the backfill material or vibration energy to the flooding cycle.Item Minnesota Phosphorus Loss: How Soil Loss Is Only Part of the Story and Why Modeling Can Be Improved by Considering Subsurface Phosphorus Loss(2021-05) Reitmeier, HeidiThis study explores 20 years of Minnesota regional phosphorus (P) management data across agricultural landscapes and how these are modeled by the Minnesota Phosphorus Index (MNPI). Nutrient-loading and farm management records from 1999-2019 were compiled across 17 different Minnesota counties representing 5 different state regions, including sites from Discovery Farms of Minnesota, Minnesota Department of Agriculture, Minnesota Agricultural Water Resource Center, and the University of Minnesota. The consolidated data cover two critical watersheds in nutrient management, one flowing north to Canada's Lake Winnipeg, the other flowing south through the Mississippi River ultimately to the Gulf of Mexico. Best management practices are needed for P loss within these watershed basins due to rising concerns about recurrent algal blooms in both watersheds. This study combines historical nutrient-loading data and farm management data to see how soil loss due to erosion impacts P losses and how the MNPI models P-loss risk.Item A Report on Field Research in Soils(Minnesota Agricultural Experiment Station, 1980)The 1980 edition of the "bluebook" is a compilation of data collected and analyzed throughout Minnesota. Information was contributed by personnel of the Department of Soil Science including Extension Soil Specialists, Scientists at the branch stations of Crookston, Grand Rapids, Lamberton, Morris, Rosemount and Waseca; the "Sand Plain" experimental sites; and Soils and Crop area agents. Associated personnel from the Soil Conservation service, the Soi1 and Water Research group of the SEA-USDA, the Tennessee Valley Authority, the Department of Natural Resources and the Departments of Agriculture also contributed information. Some of the results are from 1979 experiments only and should be regarded on this basis. Since most data are from only 1979 studies, conclusions are not conclusive and are thus not for further publication without the written consent of the individual researchers involved. Sincere appreciation is expressed for materials and/or financial assistance or program support from several organizations including: Potash and Phosphorus Institute of North America, CENEX, Farmland, Midland Cooperatives and Howe Incorporated, Minnesota Crop Improvement Association, American Soybean Association and Minnesota Soybean Research and Promotion Council, Minnesota Golf Course Superintendents Association, Minnesota Limestone Producers Association, Minnesota Plant Food and Chemicals Association, Minnesota Soil and Water Conservation Committee, Dow Chemical, Olin Corporation, Minnesota Wheat Council, Sugar beet Research and Education Board, The Minnesota Resources Commission, The Minnesota State Planning Agency, The Water Resources Research Center of the Graduate School, the Staples Vo-Tech Institute, the Red River Valley Potato Growers Association, the Tennessee Valley Authority and the North Central Forest Experiment Station. The investigators also greatly appreciate the cooperation of many county agents, farmers, technical assistants, secretaries and the representatives of the various firms and businesses who contributed time, land, machinery and materials and without whose support many of the results reported here would not have been possible.Item A Report on Field Research in Soils - Revised(Minnesota Agricultural Experiment Station, 1987)Item A Report on Field Research in Soils - Revised(Minnesota Agricultural Experiment Station, 1983)Item A Report on Field Research in Soils - Revised(Minnesota Agricultural Experiment Station, 1982)Item A Report on Field Research in Soils - Revised(Minnesota Agricultural Experiment Station, 1986)