Analysis of Microbial Communities in Thermally Stratified Freshwater Florida Lakes

Connor Tringali

Authors:  Connor Tringali, Dr. Masanori Fujimoto

Faculty Mentor:  Dr. Masanori Fujimoto

College:  College of Agricultural and Life Sciences


While a majority of Florida lakes are shallow, several deep lakes exist and are thermally stratified (divided into two layers: epilimnion and hypolimnion) during the majority of the year. However, little is known about microbial communities and their functions in each layer of these thermally stratified, subtropical Florida lakes. This study attempts to compare the epilimnion with the hypolimnion of freshwater Florida lakes in terms of both chemical and microbial factors. Water samples were collected from four deep lakes in north (Johnson and Sheelar) and central (Verona and Tulane) Florida at two depths and were analyzed for microbial communities using DNA sequencing. Alpha diversity analysis revealed that microbial diversity was significantly higher (avg~3300OTUs) in the hypolimnion than in the epilimnion (avg ~1400OTUs) An ordination plot revealed that epilimnion microbial community compositions significantly differ from those epilimnion. The effect of lake on microbial communities was also observed as microbial communities in oligotrophic lakes differ from those in meso-and eutrophic lakes. These results suggest that microbial processes that govern biogeochemical cycles in lake differ between epilimnion and hypolimnion of lakes. The data gathered in this study can be applied to understand microbial mediated biogeochemical cycles in subtropical deep lakes during stratification.

Poster Pitch

Click the video below to view the student's poster pitch.


Click the image to enlarge.
7 Responses
  1. Connor Tringali

    Connor Tringali is inviting you to a scheduled Zoom meeting.

    Topic: Undergrad Symp
    Time: Apr 2, 2020 03:00 PM Eastern Time (US and Canada)

    Join Zoom Meeting

    Meeting ID: 181 920 713

    One tap mobile
    +16465588656,,181920713# US (New York)
    +13126266799,,181920713# US (Chicago)

    Dial by your location
    +1 646 558 8656 US (New York)
    +1 312 626 6799 US (Chicago)
    +1 669 900 6833 US (San Jose)
    +1 253 215 8782 US
    +1 301 715 8592 US
    +1 346 248 7799 US (Houston)
    Meeting ID: 181 920 713
    Find your local number:

    Join by SIP

    Join by H.323 (US West) (US East) (China) (India Mumbai) (India Hyderabad) (EMEA) (Australia) (Hong Kong) (Brazil) (Canada) (Japan)
    Meeting ID: 181 920 713

    Join by Skype for Business

  2. Cayla Sullivan

    Hi Connor – Awesome project!

    I was wondering was there a latitudinal difference at all in diversity? Just curious if location mattered. Thanks!

    -Cayla Sullivan

  3. Masa Fujimoto

    I really liked the introductory part of your presentation! Thank you for sharing the bigger picture of your study.

  4. Connor Tringali

    Certainly! The two northern lakes (Johnson Pond and Sheelar) are at about 29N and the southern lakes (Tulane and Verona) 27N. They are both considered sub-tropical. The differences in latitude here may have some effect but the primary driver of the differences in diversity is definitely the productivity.