Browsing by Subject "water"
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Item An Analysis of Microlitter and Microplastics from Lake Superior Beach Sand and Surface-Water(2020-04-14) Minor, Elizabeth C; Lin, Roselynd; Burrows, Alvin; Cooney, Ellen M; Grosshuesch, Sarah; LaFrancois, Brenda; sdgrossh@d.umn.edu; Grosshuesch, Sarah; University of Minnesota Large Lakes ObservatoryAn Analysis of Microlitter and Microplastics from Lake Superior Beach Sand and Surface-Water. This report describes work done in 2018 to evaluate the presence/absence of microplastics within and near the Apostle Islands National Lakeshore. We wish to archive the information for preservation and availability for other interested parties.Item Assessment of Internal Phosphorus Release and Treatment with Iron Filings in five RPBCWD Ponds(University of Minnesota, College of Science and Engineering, 2022-06) Natarajan, Poornima; Gulliver, John S.Five ponds, Aquila Pond (in Bloomington), Pond BC-P4.10C (in Chanhassen), Bren Pond (in Eden Prairie), Pond 849_W (in Minnetonka) and Pond 42 (in Shorewood), were evaluated in this two-part study. a) In the first part of the study, the potential anoxic sediment phosphorus release was evaluated using laboratory sediment cores. A moderately-high flux of phosphate was measured under anoxic conditions, which was supported by high sediment oxygen demand and high organic matter content in the sediments. A low oxic flux was observed only for Pond BC-P4.10C and Bren Pond sediments, indicating mobilization of organic P by bacteria. Detailed sediment phosphorus characterization revealed low to moderate concentrations of mobile P (redox-P + labile organic P) mass, which is releasable under low oxygen conditions and by microbacterial degradation under both oxic and anoxic conditions. The relative mobile P mass (as % of the total sediment phosphorus mass) was 53% in Aquila Pond, 43% in Pond BC-P4.10 C, 47% in Bren Pond, 41% in Pond 42, and 63% in Pond 849_W, highlighting the importance of mobile phosphorus in driving internal phosphorus loading during anoxia in the ponds. b) In situ monitoring of surface to bottom DO and temperature profiles in the ponds were indicative of a stratified water column that was anoxic from top to bottom during much of the summer period. The observation of pervasive anoxia was common in Pond BC-P4.10C, Bren Pond, Pond 849_W, and Pond 42 during all three field seasons, as indicated by the relatively high summer anoxic factor (AF) for these ponds. Aquila Pond appeared to partially mix intermittently although bottom DO was still low during certain periods. c) All five pond sites had floating vegetation (duckweed and watermeal) that had a dense surface coverage (nearly 100%) from June to September. We have found strong evidence of duckweed cover influencing the DO dynamics in several ponds and have observed a strong pattern between summer anoxic factor and duckweed cover in our pond research projects. It is possible that the effect of duckweed may be exacerbated in dry years (like 2021) when stormwater inputs to provide direct mixing are less frequent. d) The application of iron filings was utilized to reduce phosphate release from the pond sediments. Ponds BC-P4.10C and 849_W were treated with iron filings in February 2020 and Bren Pond was treated in February 2020. Aquila Pond can be used as a control for the RPBCWD region, where surface water TP was seen to increase greatly from 2019 to 2020, and then stayed about the same in 2021. In Pond BC-P4.10C, the average TP went up after treatment with iron filings in February 2020, but not as substantially as the Aquila Pond. In Bren Pond, the average TP had a slight reduction in all three years. In Pond 849_W, the average TP went up in 2020 but then reduced in 2021. A similar reduction can be seen in comparing average TP for Shoreview Commons Pond (a fourth iron-treated pond located in the Ramsey Washington Metro Watershed District) to the Alameda Pond (located in v Roseville), where Shoreview Commons had a reduced average TP in 2021 after iron filings addition and the Alameda Pond, with no iron filings addition, did not. e) The analysis of the iron-treated sediments from Pond BC-P4.10C, Pond 849_W, and Bren Pond showed an increase in the iron-bound P mass and a concomitant decrease in the mass of labile organic P and loosely-bound P after iron filings application to the sediments, suggesting the partial or full movement of phosphate from the organic P form and loosely- bound P to iron-phosphate minerals in the sediments. The iron-treated sediment cores from Bren Pond exhibited an anoxic phosphate flux that was significantly lower than the phosphate flux from untreated sediments. f) While the column studies confirmed that sediment phosphate flux was controlled after iron addition, the reduction in internal phosphorus loading in the ponds was not directly assessed. The post-treatment water quality data showed reductions in SRP levels (surface and epilimnion) at the three iron-treated ponds but did not conclusively show reductions in TP levels, specifically in ponds BC-P4.10C and 849_W. The interpretation and assessment of treatment effectiveness is complicated by the year-to-year variation in pond water quality driven by rainfall patterns and runoff inputs among other factors, especially in ponds BC- P4.10C and 849_W, which have pretreatment data for only one year before iron filings were applied. Treatment of the ponds will likely require a combination of remediation techniques such as sealing the sediments from phosphate flux, aeration to enhance mixing and watershed-based phosphorus control actions to reduce the inflow of TP. Aeration may work well in Pond 849_W, which has a small amount of inflow or outflow.Item Berkovich nanoindentation and FTIR data describing the effect of water on olivine plasticity(2023-08-28) Kumamoto, Kathryn, M; Breithaupt, Thomas, P; Hansen, Lars, N; Wallis, David; Li, Bo-Shiuan; Armstrong, David, EJ; Goldsby, David, L; Li, Yang; Warren, Jessica, M; Wilkinson, Angus, J; lnhansen@umn.edu; Hansen, Lars, N; Rock and Mineral Physics LabThis data set contains data collected as part of a study to determine the influence of dissolved hydrogen on the mechanical properties of olivine. Nanoindentation experiments were conducted to measure the hardness of both pristine olivine crystals and olivine crystals predoped with hydrogen. The hydrogen content of samples was assessed with Fourier-transform infrared spectroscopy (FTIR). This data set includes mechanical data from indentation experiments as well as spectra from FTIR measurements.Item Budget Cuts and Environmental Programs: 1984-85.(1983) Karasov, DeborahItem C-43, Geologic Atlas of Cass County, Minnesota(Minnesota Geological Survey, 2018) Lusardi, Barbara, A; Pettus, Margeurite, C; Chandler, Val, W; Radakovich, Amy, L; Nguyen, Maurice, K; Staley, Amie, E; Hamilton, Jacqueline, DA County Geologic Atlas project is a study of a county's geology, and its mineral and ground-water resources. The information collected during the project is used to develop maps, data-base files, and reports. This same information is also produced as digital files for use with computers. The map information is formatted as geographic information system (GIS) files with associated data bases. The maps and reports are also reproduced as portable document files (PDFs) that can be opened on virtually any computer using the free Acrobat Reader from Adobe.com. Due to errors identified during work on the Part B portion of the atlas, new strat lines and sand/till rasters have been added to this site to address the issues (Revisions to sand model data 2022).Item C-46, Geologic Atlas of Kandiyohi County, Minnesota(Minnesota Geological Survey, 2019) Hamilton, Jacqueline D; Bauer, Emily J; Chandler, V.W.; Steenberg, Julia R; Staley, Amie EA County Geologic Atlas project is a study of a county's geology, and its mineral and ground-water resources. The information collected during the project is used to develop maps, data-base files, and reports. This same information is also produced as digital files for use with computers. The map information is formatted as geographic information system (GIS) files with associated data bases. The maps and reports are also reproduced as portable document files (PDFs) that can be opened on virtually any computer using the free Acrobat Reader from Adobe.com. Due to errors found when working with Part B, hydrogeology, revised sand/till rasters have been added to this site in 2022 (Revisions to sand model data 2022).Item City of Henderson: Water Resources.(1991) Bonde, KarenItem Climate change projections for improved management of infrastructure, industry, and water resources in Minnesota(2019-09-15) Noe, Ryan R; Keeler, Bonnie L; Twine, Tracy E; Brauman, Kate A; Mayer, Terin; Rogers, MaggieItem Determination of Low Density Polyethylene Water Permeability, Transport Activation Energy, and Mechanical Properties after Thermal Oxidation and Immersion in Water(2019-08) Munir, NoumonLow Density Polyethylene (LDPE) thin film was exposed to oxygen gas overpressure and water. in a Parr Instruments pressure vessel at four temperatures 22, 50, 70 and 80°C; and, at 30 and 50 psi initial oxygen pressures. Sheet polypropylene (PP) and high-density polyethylene (HDPE) as well as injection molded HDPE, HDPP, and LDPE dogbones were exposed at 70°C and 30 psi initial oxygen pressure. Immersion of LDPE films was done under and above water at 80°C and 50 psi initial oxygen pressure. Permeation cup tests were done to determine the permeability of water vapor across the LDPE film at 60, 70, and 90°C. The extent of oxidation and functionality was monitored using ATR-FTIR and was consistent with previous work on polyethylene-oxygen reaction pathways. The permeability of the LDPE films and carbonyl content increased linearly with temperature, oxidation time, and oxygen pressure. The dogbones studied showed little change in mechanical properties.Item The Development of a Novel Capacitive Water Conductivity Sensor(2018-05) Cantilina, KeiranA novel sensor was developed which measures water conductivity by tracking the capacitance of two insulated probes submerged in the water under test. Unlike commercially available water conductivity sensors based on 4-terminal potentiometric methods, this sensor does not require metal to be in direct contact with water. In addition, this sensor has much higher sensitivity and lower power consumption compared to induction-based conductivity sensors. These differences make this sensor uniquely suited for use in distributed sensor networks, where resistance to corrosion and fouling, low power consumption, and reliability are necessary traits. Lastly, this sensor is a good fit for use by citizen scientists or hobbyists due to the ease of assembly and the low price of components needed to construct the device.Item The EKOCENTER: A Case Study in Coca-Cola, Corporate Social Responsibility, and Bluewashing(2015-05) Hamilton, JoyIn 2013 The Coca-Cola Company announced their latest corporate social responsibility (CSR) project: the EKOCENTER. Envisioned for communities lacking access to safe drinking water, the EKOCENTER kiosks contain vaccine storage, wireless communication technology, clean drinking water, and Coca-Cola products under the premise of "social enterprise."� In light of the global water crisis, a textual and visual analysis of the CSR press release materials produced by The Coca-Cola Company in addition to media coverage highlights the ways in which Coca-Cola utilizes public concern about the environment and public health in order to safeguard their position as the world's largest beverage distributer. The EKOCENTER's discourse exemplifies "bluewashing"� rhetoric that contests negative perceptions of Coca-Cola. Furthermore, the EKOCENTER discourse glosses over the contradiction between Coca-Cola's reliance on water access for their business model and Earth's limited fresh water supply. The EKOCENTER embodies a precarious deferment of water stewardship and governance to transnational corporations.Item Farm Legal Series: Minnesota Water Law Basics, 2015(University of Minnesota Extension, 2015-06) Kunkel, Phillip A.; Peterson, Jeffery A.Item Farm Legal Series: Minnesota Water Law Basics, 2020(University of Minnesota Extension, 2020-04) Kunkel, Phillip A.; Peterson, Jeffery A.Item Forest Resource Management in Southeast Minnesota(2002) Class, LeahItem Friends of the Vermillion River Water Trail Study(2005) Ochs, ChristopherItem Growth, Motility and Metabolism of Harmful Cyanobacteria and Lipid-Producing Microalgae in Fluid Environments: From Laboratory to Field Study(2020-08) You, JiaqiMicroorganisms have been playing important roles in aquatic environments, including the beneficial roles in ecosystem functioning and metabolites production as potential nutrient and energy sources, and the harmful roles in water quality such as harmful algal blooms (HABs). Cyanobacteria blooms have been a worldwide threat to the ecological integrity and environmental health of the freshwater bodies due to the progressive anthropogenic activities and climate change. The complex and combined interactions of environmental variables on the growth, buoyancy and metabolism (e.g., toxin production) make the prediction and management of cyanobacteria blooms and their toxicity difficult. On the other hand, microalgae have been shown as a potential bioresource for food, biofuel, and pharmaceutical products. During the growth phases with corresponding environmental conditions, microalgae accumulate different amounts of various metabolites. The neutral lipid content accumulated in the lipid-producing microalgae cells, which can be transferred to biodiesel, varies with growth conditions. This dissertation improves the understanding of growth, motility (swimming or buoyancy regulations) and metabolism of cyanobacteria and lipid-producing algae in fluids with influences of various environmental variables, in order to maximize the efficieney of microalgal biofuel production and to minimize the harmful effects of cyanobacteria HABs. In the laboratory study of cyanobacteria, batch cultures of Microcystis aeruginosa (M. aeruginosa) were cultivated at seven different temperatures to measure the specific growth rate at each temperature. A relationship between temperature and specific growth rate was established. We propose a cardinal temperature model for M. aeruginosa with the inflection point (optimal temperature) located at 27.5˚C. The model describes 98% of the variability of experimental data from 5˚C to 35˚C. A digital inline holographic microscope was employed to visualize and analyze the buoyancy of the M. aeruginosa colonies at two different temperatures. The results demonstrated a five times difference in buoyant velocities of M. aeruginosa colonies at 17.5˚C and 28˚C. A model was derived to calculate the density of a colony using the buoyant velocity and colony size. The findings provide a better understanding of temperature effects on the growth and buoyancy of M. aeruginosa. The results could facilitate the prediction of cyanobacteria blooms and the development of water quality models for freshwater ecosystems. In the laboratory study of lipid-producing microalgae, the neutral lipid accumulation was quantified and the swimming signatures (speed and trajectories) were analyzed for the motile green alga, Dunaliella primolecta, during the lag-exponential-stationary growth cycle at different nutrient concentrations. We discovered significant changes in the neutral lipid content and swimming signatures of microalgae across growth phases. The timing of the maximum swimming speed coincided with the maximum lipid content and both maxima occurred under nutrient stress at the stationary growth phase. Furthermore, the swimming trajectories suggested statistically significant changes in swimming modes at the stationary growth phase when the maximum intracellular neutral lipid content was observed. The results provide the potential exploitation of microalgal swimming signatures as possible indicators of the cultivation conditions and the timing of microalgal harvest to maximize the lipid yield for biofuel production. The findings can also be implemented to explore the production of food and antibiotics from other microalgal metabolites with low energy costs. In the field study of cyanobacteria blooms, we investigated the concentrations of cyanobacteria and microcystins in a small stratified lake and examined the influence of the abiotic environmental factors on the vertical and temporal heterogeneities. The results demonstrated the similarities in the vertical heterogeneities of cyanobacteria biovolume and total microcystin concentration. Similar patterns were discovered in vertical variations of macronutrient ratio of nitrogen over phosphorus (N:P) and biovolume ratio of non-N-fixing over N-fixing cyanobacteria. Moreover, temporal lags were revealed between the maxima of cyanobacteria biovolume, total microcystin level and Microcystis colony size. The stability of water column significantly affected the maximum Microcystis colony size, the surface cyanobacteria biovolume and the surface microcystin concentration. Correlations were established between the temporal heterogeneities of cyanobacteria community composition and the macronutrient dynamics. The findings and their implications on the environmental health will facilitate the development of prediction models and management strategies in the effort to control the impacts of cyanobacteria and cyanotoxins in small to medium size stratified lakes.Item Increasing environmental knowledge and effecting change in lawn maintenance behavior among homeowners(2015-12) Leslie, MadelineThe management of private property in urban areas can greatly influence the amount of fertilizer, soil, and water runoff into surrounding watersheds, increasing nitrogen and phosphorus pollution and creating eutrophic conditions in water bodies. Lawns are a prominent component of managed landscapes, and as such can play a role in water pollution levels over time. Encouraging beneficial maintenance behaviors has the potential to reduce nutrient runoff from turfgrass areas and increase the ecosystem services they provide. However, there are complex reasons why private property owners make lawn and yard care decisions. In addition, members of the public often do not understand the path water travels when it leaves their property. Therefore, the objectives of this study are to assess whether or not an individual’s possession of inaccurate water pathway knowledge is related to their lawn and yard maintenance behavior, as well as to determine the effectiveness of video and written educational interventions in changing the behavior and intent to behave of individuals. Surveys of Twin Cities Metro Area, MN residents were conducted 2014 and 2015. Based on their answers, respondents were divided into two groups; those who had obvious misconceptions about runoff water pathways and those who did not. Approximately 32% of survey participants had misconceptions about runoff water pathways. In addition, there were significant differences regarding about the effects of maintenance activities, as well as the frequency of lawn watering, mowing, and fertilizer use. A follow-up survey of the June, 2014 respondents did not indicate a change in maintenance behavior after viewing the educational video, but a comparison between two intervention methods on influencing and individual’s intent to behave found that a written intervention was more effective than video. This information will help inform and direct public outreach and education efforts to help improve local water quality in urban areas.Item Increasing Participation in the Minnesota Agricultural Water Quality Certification Program (MAWQCP)(2023) Kaste, Grant A; Gross, Peter S; Greene, GraceSince 2012, the Minnesota Department of Agriculture (MDA) has operated the Minnesota Agricultural Water Quality Certification Program (MAWQCP) for farmers in the state. This voluntary program certifies farmers who implement certain conservation practices that aim to improve soil and water quality. Participation in the program has slowed since its inception and remains lower than the MDA would like. This report explores methods to increase participation in the program, evaluates environmental impacts the program has delivered thus far, analyzes the costs and benefits of the program, and assesses stakeholder views of the program. Methods included utilizing available data, outreach to stakeholders, information gathering from various program meetings, and a literature review of relevant research. Our findings indicate a need for more robust data collection regarding the benefits of the program and non-participant insights, more collaboration with industry and similar programs in other states, and marketing of the program on a watershed-level basis and as one of a stack of programs available to farmers. These findings directly support our offered recommendations and other considerations to work towards the goal of improving water quality and growing conservation minded practices.Item Investigation of vascular limitations on floral water loss in temperate woody species(2018-12) McMann, NatalieIn temperate biomes, limitations imposed by vascular physiology may influence floral water use in woody species. Freeze-thaw induced embolism in the xylem can reduce vascular transport capacity in the early spring, potentially limiting growth. To investigate whether xylem transport capacity impacts floral physiology, I quantified inflorescence water loss rates and stem hydraulic conductivity of five woody species that flower before producing leaves. I found inflorescence size and ambient temperature at flowering positively correlated with water loss. However, I detected no correlation between branch level floral water loss and stem hydraulic conductivity within species. Furthermore, a comparison of branch level water loss rates from inflorescences and leaves showed that leaf water loss is 2–4 orders of magnitude greater than that of flowers. To evaluate whether flowers were primarily phloem or xylem hydrated, I modeled the amount of water brought in during floral development and full bloom. Despite their relatively low rates of water loss, the model indicates that flowers in this study obtain the majority of their water from the xylem. Overall, the data suggest that within species floral water loss may not be limited by the xylem during flowering, but large differences in floral water loss and stem conductivity among species could explain hydraulic trait variation between large and small flowered plants.