University of Massachusetts Amherst ScholarWorks@UMass Amherst Doctoral Dissertations Dissertations and Theses Fall November 2014 TURNING UP THE HEAT ON THE LITTLE THINGS THAT RUN THE WORLD: EVALUATING THE IMPACTS OF CLIMATE CHANGE ON ANT BIODIVERSITY IN THE TEMPERATE FOREST COMMUNITIES OF THE NORTHEASTERN UNITED STATES Israel Del Toro University of Massachusetts - Amherst Follow this and additional works at: https://scholarworks.umass.edu/dissertations_2 Part of the Terrestrial and Aquatic Ecology Commons Recommended Citation Del Toro, Israel, "TURNING UP THE HEAT ON THE LITTLE THINGS THAT RUN THE WORLD: EVALUATING THE IMPACTS OF CLIMATE CHANGE ON ANT BIODIVERSITY IN THE TEMPERATE FOREST COMMUNITIES OF THE NORTHEASTERN UNITED STATES" (2014). Doctoral Dissertations. 176. https://doi.org/10.7275/vk8p-ae52 https://scholarworks.umass.edu/dissertations_2/176 This Open Access Dissertation is brought to you for free and open access by the Dissertations and Theses at ScholarWorks@UMass Amherst. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. TURNING UP THE HEAT ON THE LITTLE THINGS THAT RUN THE WORLD: EVALUATING THE IMPACTS OF CLIMATE CHANGE ON ANT BIODIVERSITY IN THE TEMPERATE FOREST COMMUNITIES OF THE NORTHEASTERN UNITED STATES A Dissertation Presented by ISRAEL DEL TORO Submitted to the Graduate School of the University of Massachusetts Amherst in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY SEPTEMBER 2014 Organismic and Evolutionary Biology © Copyright by Israel Del Toro 2014 All Rights Reserved TURNING UP THE HEAT ON THE LITTLE THINGS THAT RUN THE WORLD: EVALUATING THE IMPACTS OF CLIMATE CHANGE ON ANT BIODIVERSITY IN THE TEMPERATE FOREST COMMUNITIES OF THE NORTHEASTERN UNITED STATES A Dissertation Presented by ISRAEL DEL TORO Approved as to style and content by: _______________________________________ Aaron M. Ellison, Chair _______________________________________ John T. Finn, Member _______________________________________ Bethany A. Bradley, Member _______________________________________ Nicholas J. Gotelli, Member ____________________________________ Elizabeth R. Dumont, Director Organismic and Evolutionary Biology DEDICATION This work is dedicated to my loving wife, mother and grandmother for their support and encouragement over many years. ACKNOWLEDGMENTS This work could not have been completed without countless hours of support from my main advisor Aaron Ellison, I am grateful for his advice, motivation and encouragement. I also want to thank my dissertation committee for their input on many drafts of this dissertation, Bethany Bradley, Jack Finn and Nick Gotelli. Many of the chapters and publications resulting from this work were completed in collaboration with Shanon Pelini, Relena Ribbons, Nate Sanders and Rob Dunn. I especially thank the massive effort from my former undergraduate students: Adam Clark, Natashia Manyak, Drew Morrison, Kevin Towle, Michael Marquis, Katie Davis, Matt Combs, Lilian Carpene, Ariane Bouily. These students worked with me for many hours and were supported by the Harvard Forest REU program and the CSIRO student internship program. A special thank you goes to Ms. Penny Jaques and the OEB, the Harvard Forest and the NEAGEP faculty and staff and community. Funding sources for this dissertation were: National Science Foundation (GRFP), The Northeast Alliance for Graduate Education and the Professoriate, The Australian-American Fulbright Program, National Geographic, The American Philosophical Society, CSIRO, the Ecological Society of America, The American Museum of Natural History, The UMass Natural History Collections Grand and the Academy of Natural Sciences. v ABSTRACT TURNING UP THE HEAT ON THE LITTLE THINGS THAT RUN THE WORLD: EVALUATING THE IMPACTS OF CLIMATE CHANGE ON ANT BIODIVERSITY IN THE TEMPERATE FOREST COMMUNITIES OF THE NORTHEASTERN UNITED STATES SEPTEMBER 2014 ISRAEL DEL TORO, B.S. UNIVERSITY OF TEXAS EL PASO M.S. UNIVERSITY OF MASSACHUSETTS AMHERST Ph.D., UNIVERSITY OF MASSACHUSETTS Directed by: Aron M. Ellison Climatic change threatens biodiversity worldwide. In the forests of the northeastern United States, climate change is expected to increase mean annual temperatures by up to 4.5˚C and change precipitation seasonality. These changes in climate are likely to have impacts on the biodiversity of the region. In order to better understand the impacts of climate change on biodiversity, I used ants, an indicator taxonomic group, to predict how ant communities and ant-mediated ecosystem processes change as the climate warms. In the first chapter of this dissertation, I review the major ecosystem processes and services mediated by ants using the Millennium Ecosystem Assessment framework. In chapter two of this dissertation I present the results of a major ant sampling effort along environmental gradients of the Appalachian region of the northeastern United States. In 2010 I sampled ant communities in forested and open habitats at 67 localities from Virginia north to Maine and developed macroecological models which show that ant community composition in forested habitats can be explained vi by the region’s climatic properties. In chapter three, I intensively sampled open and forested plots at Harvard Forest LTER and Myles Standish State Forest in eastern Massachusetts. In chapter four, I present the results of a warming mesocosm experiment using the ant species Formica subsericea. I found that as warming increases, soil movement and soil respiration increases but decomposition and nitrogen availability decreases. In the final chapter of this dissertation, I use different functional diversity and species distribution models to classify the ant communities of the region into different functional groups and explore how their distributions will change in future climates. In this dissertation, I show that ant diversity and ant-mediated ecosystem processes are likely to change under future environmental and climatic conditions. I used observational, experimental and modeling approaches to evaluate and predict the consequences of climatic change on the biodiversity of ants in the northeastern U.S. Ants are considered to be amongst the little things that run the world, and the impacts of climatic change on their communities, abundances, distributions are likely to have major impacts on the forests of the region. vii TABLE OF CONTENTS Page ACKNOWLEDGMENTS ...................................................................................................v ABSTRACT ....................................................................................................................... vi LIST OF TABLES ............................................................................................................. xi LIST OF FIGURES .......................................................................................................... xii CHAPTER 1: THE LITTLE THINGS THAT RUN THE WORLD REVISITED: A REVIEW OF ANT-MEDIATED ECOSYSTEM SERVICES AND DISSERVICES ............2 Chapter Summary ....................................................................................................2 Introduction ..............................................................................................................2 Ant biodiversity and provisioning, regulating and cultural ecosystem services .........................................................................................................6 Provisioning services ...................................................................................6 Regulating services ......................................................................................8 Cultural services.........................................................................................15 Ant biodiversity and supporting ecosystem services and ecosystem function ..........................................................................................16 Nutrient cycling .........................................................................................18 Carbon cycling ...........................................................................................19 Soil formation, structure, and nutrient retention ........................................20 Decomposition ...........................................................................................21 Ecosystem structure and function ..............................................................22 Bioindicators ..............................................................................................22 Linking ant-mediated ecosystem processes and services ......................................29 Ant-mediated ecosystem disservices .....................................................................30 Research needs .......................................................................................................34 Discussion and conclusion .....................................................................................38 2: DIVERSITY OF EASTERN NORTH AMERICAN ANT COMMUNITIES ALONG ENVIRONMENTAL GRADIENTS ......................................................41 Chapter Summary ..................................................................................................41 Introduction ............................................................................................................42 Materials and Methods ...........................................................................................44