Browsing by Subject "mesocosm"

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    Evaluation Of A Method For Ballast Water Risk-Release Assessment Using A Protist Surrogate
    (2015-08) Aliff, Meagan
    Aquatic invasive species cost the United States billions of dollars annually and are most often introduced via ships' ballast tanks. The International Maritime Organization (IMO) adopted a set of standards that sets limits on the number of viable organisms that can be discharged with ballast water. These standards require scientific research to determining the risk-release relationship (i.e. the number of propagules needed for an invasion). To examine the risk-release relationship a surrogate invader, the diatom Melosira varians, was used. Varying densities of the surrogate were added to 19-L mesocosms containing water from Duluth-Superior Harbor. Each mesocosm was sampled weekly for four weeks and the response of the phytoplankton community was measured via cell counts. Population responses varied by starting conditions but M. varians establishment was generally noted at higher inoculation densities. These findings suggest the mesocosm approach can inform the understanding of risk-release relationships.
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    Minnesota Pollution Control Agency Wild Rice Sulfate Standard Mesocosm Study: Water, Sediment, and Porewater "Synoptic" Sampling 2013 and 2015
    (2017-05-30) Myrbo, Amy; amyrbo@umn.edu; Myrbo, Amy
    This dataset represents opportunistic, "synoptic" sampling of 30 experimental mesocosms for chemical parameters. The mesocosm experiments were undertaken by Dr. John Pastor (UMN-Duluth) and the Minnesota Pollution Control Agency (MPCA) to improve the understanding of why wild rice (Zizania palustris, manoomin, psin) is observed to thrive only in waters with low sulfate (SO4), and to contribute to evaluation of Minnesota Rules 7050.0224, promulgated in 1973, which seeks to limit the exposure of wild rice to sulfate concentrations exceeding 10 mg/L.The dataset is now released as manuscripts using it are being published.