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The Influence of Zostera Marina and Ruppia Maritima on Habitat Structure and Function in a Changing Environment in the Chesapeake Bay W&M ScholarWorks Dissertations, Theses, and Masters Projects Theses, Dissertations, & Master Projects 2015 The Influence of osterZ a marina and Ruppia maritima on Habitat Structure and Function in a Changing Environment in the Chesapeake Bay Emily D. French College of William and Mary - Virginia Institute of Marine Science Follow this and additional works at: https://scholarworks.wm.edu/etd Part of the Marine Biology Commons, and the Oceanography Commons Recommended Citation French, Emily D., "The Influence of osterZ a marina and Ruppia maritima on Habitat Structure and Function in a Changing Environment in the Chesapeake Bay" (2015). Dissertations, Theses, and Masters Projects. Paper 1539617956. https://dx.doi.org/doi:10.25773/v5-gct9-0e76 This Thesis is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Dissertations, Theses, and Masters Projects by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. The Influence of Zostera marina and Ruppia maritima on Habitat Structure and Function in a Changing Environment in the Chesapeake Bay A Thesis Presented to The Faculty of the School of Marine Science The College of William and Mary in Virginia In Partial Fulfillment of the Requirements for the Degree of Master of Science by Emily D. French 2015 ProQuest Number: 10632133 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest. ProQuest 10632133 Published by ProQuest LLC (2017). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106 - 1346 APPROVAL SHEET This thesis is submitted in partial fulfillment of the requirements for the degree of Master of Science C Emily D. French Approved, by the Committee, July 2015 m y Kenneth Moore, Ph.D. Committee Chairman/Advisor A-jtX Robert Orth, Ph.D. Bongkeun Song, Ph.D. T Q > J l Carl Friedrichs, Ph.D. TABLE OF CONTENTS Page ACKNOWLEDGEMENTS ..........................................................................................................iv LIST OF TABLES .....................................................................................................................v LIST OF FIGURES ....................................................................................................................vi THESIS ABSTRACT.................................................................................................................. vii CHAPTER 1 .....................................................................................................................1 ABSTRACT .....................................................................................................................2 INTRODUCTION .....................................................................................................................3 Seagrasses in the Chesapeake Bay ...........................................................................5 Ecosystem Services ................................................................................................... 8 Sediment Stabilization and Erodibility .........................................................8 Epifaunal Abundance and Richness .............................................................10 Objectives and Hypotheses ....................................................................................... 12 METHODS...............................................................................................................................14 Site and Habitat Type Selection ................................................................................ 14 Biomass Sampling..................................................................................................... 15 Sediment Characterization ....................................................................................... 15 Epifauna Sampling.................................................................................................... 16 Sediment Erodibility .................................................................................................. 16 Data Analyses .............................................................................................................18 RESULTS..................................................................................................................................21 Water Temperature .................................................................................................. 21 Biomass and Shoot Density ....................................................................................... 22 Grain Size and Erodibility .......................................................................................... 26 Epifaunal Abundance and Richness ..........................................................................30 DISCUSSION........................................................................................................................... 33 ii LITERATURE CITED 40 CHAPTER 2 ..............................................................................................................................50 ABSTRACT ..................................................................................................................... 51 INTRODUCTION ..................................................................................................................... 52 Objectives and Hypotheses ....................................................................................... 55 METHODS...............................................................................................................................56 Sediment Microbial Community Analysis .................................................................56 Sediment Organic Matter and Pore Water Nutrients .............................................. 58 RESULTS..................................................................................................................................59 Microbial Community ............................................................................................... 59 Biomass..................................................................................................................... 64 Sediment Characteristics .......................................................................................... 66 DISCUSSION........................................................................................................................... 69 LITERATURE CITED................................................................................................................. 71 iii ACKNOWLEDGEMENTS First of all I'd like to thank Ken Moore, my major advisor. I'm unbelievably grateful for Ken's guidance and support over the past 3 years. He was active in every aspect of the project, and his door was always open for feedback and advice. One of the things that I've appreciated the most about Ken over the past few years is his ability to be positive in stressful situations. It doesn't hurt that he's a lot of fun and is always the first person dancing at a conference, either! Next, my committee members, Robert Orth, Bongkeun Song, and Carl Friedrichs each played integral parts in this research. BK, thank you all your time spent teaching me molecular techniques and coaching me through the bioinformatics programs. You were a huge asset to this project, and always have a great attitude and laugh and shrug it off when something goes wrong in the lab. JJ, thank you for letting me use your lab and lab members' expertise for learning how to ID epifauna, for orchestrating paper review sessions, taking me out in the field to see the Eastern Shore restoration, but most importantly, for being comedic relief by teasing AJ about peanut butter sandwiches. Carl, thanks so much for your help with the erodibility measurements, and letting me work in your lab and with your team, and for having me on the research cruise on the R/V Sharp. I had wonderful mentors at VIMS- Erin Shields, Ashley Smyth, Kelsey Fall, and Jon Lefcheck, to name a few. Erin was there for me from day one, and always helped, no matter how many questions I had, on top of her already full plate as our lab's marine scientist. I'm so grateful for Ashley Smyth and Kelsey Fall, who both were willing to collaborate and contribute their areas of expertise to the project; they were both always cheerful and energetic even when I wasn't. Jon helped me with countless statistics issues when he could have been working on his own work, which I can't thank him enough for. Thank you to my VIMS lab, to Betty, Steve for always being patient and letting me drive the boat, and for recommending me for my current job! Thanks to Tavis, who was our lab tech in 2013, and processed so many biomass samples he dreamt about them. To my NERRS family, Eduardo who always had great life advice, Alynda, Joy and Lisa for always being encouraging and smiling, and to Sally. Finally, thank you to my friends and family. My Mom, Dad and Stepmom put up with seagrass
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