University of Nevada, Reno Untangling patterns of plant and arthropod diversity in a fire-adapted ecosystem: Dynamic relationships between fire, scale, and trophic interactions in longleaf pine forests. A dissertation submitted in partial fulfillment of the requirement for the degree of Doctor of Philosophy in Ecology, Evolution, and Conservation Biology By Jane E. Dell Dr. Lee A. Dyer/Dissertation Advisor August, 2018 THE GRADUATE SCHOOL We recommend that the dissertation prepared under our supervision by JANE E. DELL Entitled Untangling patterns of plant and arthropod diversity in a fire-adapted ecosystem: Dynamic relationships between fire, scale, and trophic interactions in longleaf pine forests. be accepted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Lee Dyer, Advisor Lora Robinson, Committee Member Elizabeth Leger, Committee Member Joseph O'Brien, Committee Member Vincent Catalano, Graduate School Representative David W. Zeh, Ph. D., Dean, Graduate School August, 2018 i ABSTRACT Fire has been a part of terrestrial ecosystems since the Silurian Period and is an essential process for maintaining both ecosystem function and biological diversity in fire dependent ecosystems, such as longleaf pine (Pinus palustris Mill.). In these frequently burned fire-dependent ecosystems, fire frequency is positively correlated with high species diversity. The removal of fire from the landscape initiates a shifting ecosystem trajectory where fire-adapted species are replaced by other species assemblages, yielding an alternative stable state. Patterns of biodiversity and the mechanisms driving them must be thoroughly understood to guide an effective monitoring and resource management programs. I describe cross-scale spatial and temporal patterns of plant and arthropod diversity, identification of the grain size and sampling effort to maximize efficiency in monitoring diversity, fine-scale examination of the role of fire in driving patterns of diversity, and mechanisms linking fire, biological diversity, and forest structure. Understanding these links mechanistically is critical for both guiding management now and in the future under the novel conditions expected with global change. By sampling arthropod diversity and creating linkages to plant diversity at multiple spatial and temporal scales, I could better understand how both plant and animal communities, as well as their interactions, are organized with respect to presence or absence of fire. My quantification of multiple dimensions of diversity, including taxonomic and functional metrics, reflect the current focus of biodiversity researchers in both basic and applied realms and further provides novel insight into debates about neutrality and ii correlations between diversity, stability, resiliency, and ecosystem services The interaction diversity measure is particularly important for linking biodiversity to the trillions of dollars of ecosystem services that are provided by natural ecosystems, since those services are all due to a diverse mix of ecological interactions. Taken together, these metrics of diversity can act as more sensitive indicators of how ecological communities respond to management activities, disturbances, or global change parameters. iii ACKNOWLEDGEMENTS I first and foremost want to express my gratitude to my advisor, Dr. Lee Dyer for giving me the opportunity to join his lab. You have taught me the meaning of collaboration by surrounding oneself with talented and amazing people – a model of friends as colleagues and elevating research to exceptional heights. I truly appreciate your dedication to my professional development and providing me an alternative perspective on research and a career in science. I am grateful for your generosity, especially the tireless assistance with editing, your art of storytelling, passion for biodiversity, and the chance to participate in an incredible citizen science project. I’d like to thank Dr. Lora Robinson for her overwhelming personal generosity by keeping my daughter well-dressed and looking polished. I appreciate the support you’ve given me in the lab and field, your accessibility and open door, willingness to listen, and your ability to distill the complex into the tangible. You are an exemplary role model for professionalism, patience, inclusiveness, perseverance, effective communication, and contagious laughter. My dissertation work could not have been completed without the exceptional work of my collaborators. It has been a pleasure to work with such a stellar crew and I’ve enjoyed the process of watching how our individual contributions strengthen our collective effort. I’d like to especially acknowledge Dr. Joe O’Brien for being the epitome of having fun while doing cutting-edge, sophisticated research. I appreciate your passion for fire ecology and defining success in terms of enabling and promoting those around you. I also want to thank Dr. Louise Loudermilk for her willingness to help and iv show me what it means to be a remarkable female scientist. Finally, I want to recognize Scott Pokswinski - aka “Daisy Cutter”, for assistance in the field, consistently having a repertoire of corny jokes, and keeping me from getting blown up at Eglin AFB. I am grateful for the contribution of numerous folks that have assisted and enhanced my dissertation. Thank you to my committee for your time and suggestions in improving my research. I have had the great fortune of working with volunteers with the Earthwatch Institute who taught me the absolute joy of fostering a foundation for future scientists. I appreciate their incredible field effort and contributions towards an impressive dataset of biological interactions and resulting manuscripts. I’d also like to recognize the efforts of Dyer Lab volunteers, especially the work of Lydia Doan and Rainier Pinili, for meticulously and tirelessly processing and curating thousands of individual specimens. My work has also been significantly improved through the contributions of the Dyer Lab group through reviewing manuscripts, grant applications, and presentations over the years. I feel incredibly fortunate to have such an amazing academic family. I’d also like to thank Eglin AFB fire managers, especially Brett Williams and his crew for access to prescribed fires. Without their allowing me to tag along on burns, I would not have the unique data set involving arthropod dispersal during fires. The willingness to support research while conducting logistically challenging operations makes Eglin a truly distinctive location for the continued advancement of fire science. This body of work would not have been possible without the following sources of financial support: The Department of Defense’s Strategic Environmental Research and v Development Program, the Earthwatch Institute, and UNR’s Ecology, Evolution, and Conservation Biology program, Whittell Forest, and Graduate Student Association. Most importantly, I want to thank my family. To my husband, Sean, for sacrificing a tremendous amount so that I might pursue this opportunity and to my daughter Sophie, for keeping me laughing when times got difficult. I honestly could not have done this without your love and support. “If I have seen further, it is by standing upon the shoulders of giants.” Sir Isaac Newton Thank you all for being my giants. vi TABLE OF CONTENTS ABSTRACT........................................................................................................................ i ACKNOWLEDGMENTS .................................................................................................iii TABLE OF CONTENTS....................................................................................................vi LIST OF TABLES.............................................................................................................vii LIST OF FIGURES .........................................................................................................viii INTRODUCTION ..............................................................................................................1 CHAPTER 1 – Additive partitioning of plant species diversity across Eglin Air Force Base.........................................................................................................................7 CHAPTER 2 - Overstory-Derived Surface Fuels Mediate Plant Species Diversity in Frequently Burned Longleaf Pine Forests.............................................................34 CHAPTER 3 - Quantifying the effects of burning on the diversity of arthropods in a fire- adapted longleaf pine (Pinus palustris) forest ......................................................70 CHAPTER 4 - An arthropod survival strategy in a frequently burned forest................100 CHAPTER 5 - A New tachinid genus and species record for North America: Iceliopsis borgmeieri Guimarães.........................................................................................109 CHAPTER 6 - Scale dependent patterns in interaction diversity maintain resiliency in a frequently disturbed ecosystem ...........................................................................119 CONCLUSION................................................................................................................149 LITERATURE CITED....................................................................................................156 vii LIST OF TABLES Table 1-1: Empirical additive partitioning of plant diversity in the inventory and monitoring datasets