Icon for: Jonathon Gray

JONATHON GRAY

Kent State University
Years in Grad School: 1

Judges’ Queries and Presenter’s Replies

  • May 20, 2013 | 07:23 p.m.

    This seems like a very worthwhile project but I’d like a bit more information on the current methods you are hoping to improve over and why you think you approach will indeed improve over them.

  • Icon for: Jonathon Gray

    Jonathon Gray

    Presenter
    May 23, 2013 | 06:17 p.m.

    We (our IGERT cohort and project members) saw the major drawbacks of current methods to be the cost of purchasing an (singular) in situ methane sensor (upwards of $10,000) and the spatiotemporal variability of methane ebullition. Our goal is to develop a relatively cheap and accurate sensor that can be deployed and left in the field to monitor real-time emission rates, which can then be used to assess land-use effects on microbial methanogenesis. Hope that helps!
    Best,
    Jon

  • May 21, 2013 | 06:59 p.m.

    Please explain the method you will use for validating and calibrating the prototype sensor that you plan to manufacture. How will you measure the correct level of methane concentration in water? What percentage of errors will you accept for measurements obtained by your sensor? If the results of calibration are not satisfactory, are there alternative designs that you can attempt?

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    Jonathon Gray

    Presenter
    May 23, 2013 | 06:17 p.m.

    Hello,
    This is a group project and I really wish the chemical physicists were here, as they are the minds behind the design! In any case, we plan to validate using currently employed methods (collar collection and with a purchased in situ methane sensor). Calibration will be performed using standards of known aqueous methane concentrations. We haven’t discussed accuracy requirements, but unless it can compete with current methods, there would definitely need to be some tweaking done—of course, this is also based on the needs of the user.
    A total of three possible designs have been discussed, with the simplest (and hence cheapest) design being chosen for the initial prototype. The complexity and estimated costs increase with the other designs, but we believe that they would still be lower than currently available sensors, so we haven’t entirely ruled them out!
    Hope this answers your questions!
    Best,
    Jon

  • May 21, 2013 | 09:20 p.m.

    This is an exciting project. It seems as if in the future study at Tinker’s Creek, you will be examining interactions between human and natural methane production. What hypotheses do you have about possible effects of different human land uses (urban, agricultural, etc.) on biogenic production of methane in water bodies?

  • Icon for: Jonathon Gray

    Jonathon Gray

    Presenter
    May 23, 2013 | 06:17 p.m.

    Thank you! Well, there are two things that we (this is a group project for our IGERT cohort) are expecting to play a role in methanogenesis: nutrient loading and water velocity. We expect to see an increase in methanogenic bacteria in areas of increased nutrient availability (areas of high agriculture/urbanization), however this doesn’t necessarily mean that methanogenesis will be occurring at a greater rate. The water velocity is also an issue to consider as pools are the site of higher rates of methane production due to reduced oxygen availability. Land cover (impervious surfaces, riparian areas) can affect flow and pooling, so this, too, is important to consider. Of course, this is an oversimplification (focusing on two variables for the sake of brevity), but we are expecting more biogenic methane in agricultural areas due to higher nutrient and relatively (to urban areas) lower impervious surface area.
    Hope that answers your question; I’m looking forward to getting started to see how this pans out!
    Best,
    Jon

  • Further posting is closed as the competition has ended.

Presentation Discussion
  • May 20, 2013 | 12:18 p.m.

    Wow! Hilarious and informative.

    Are you comparing sensor data to GC data from gas sampled from collars?

    Thanks!

  • Icon for: Jonathon Gray

    Jonathon Gray

    Presenter
    May 20, 2013 | 01:08 p.m.

    Thank you! We (cohort and I) wanted to make it fun, or at least a tad bit entertaining. And yes, the plan is to collect samples from collars and to compare them to in situ measurements collected by the sensor of our own design as well as a currently available in situ sensor (model TBD as of this reply).
    Best,
    J

  • Icon for: Andrea Dietrich

    Andrea Dietrich

    Faculty
    May 22, 2013 | 04:15 p.m.

    Interesting and timely project. Can you tell us more about the sensory, such as aqueous or gas phase measurements? How are you validating the sensitivity of the sensor?

  • Icon for: Jonathon Gray

    Jonathon Gray

    Presenter
    May 23, 2013 | 06:16 p.m.

    We are really interested in capturing aqueous concentrations and plan on validating the sensitivity through comparisons to other means of measuring methane production, such as a gas collar approach and using a currently available in situ sensor, and through the creation of some internally developed standards. Fortunately we have some chemical physicists on the project!
    Best,
    Jon

  • Icon for: Graham Fogg

    Graham Fogg

    Faculty
    May 23, 2013 | 01:24 p.m.

    Intriguing study. I wonder if depth to the water table might be an important variable here, since most of the wetlands are sustained by groundwater discharge. I.e., regional groundwater conditions might be at least as important as land use and ecological conditions.

  • Icon for: Jonathon Gray

    Jonathon Gray

    Presenter
    May 23, 2013 | 06:16 p.m.

    Definitely true! Luckily this is a team project consisting of members from across many disciplines, so we do have a geologist working with us who has been tasked with getting groundwater information. Underlying geologic formations and groundwater seeps will be contributors/carriers of geologically derived methane, so it is essential that this is accounted for to allow for partitioning of the total methane pool into its geo- and biogenic components.
    Best,
    Jon

  • Further posting is closed as the competition has ended.