THE ECOLOGY OF AERIAL ALGAE Jennifer A. Ress A Dissertation Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 2012 Committee: Rex L. Lowe, Advisor John T. Chen Graduate Faculty Representative George S. Bullerjahn Jeffrey R. Johansen Daniel M. Pavuk ii ABSTRACT Rex Lowe, Advisor The ecology and adaptations of aerial algal communities from selected areas in North America were examined. First, morphological adaptations to desiccation as well as microhabitat preference of diatoms were explored from the Great Smoky Mountains National Park (GSMNP). Reduced size as an adaptation against desiccation was not supported by the data, with aerial diatoms being longer than had been previously shown in the literature. However, a reduction in the amount of open area on the valve face as an adaptation against desiccation was supported by the data. Second, aerial algal communities from the GSMNP and the Lake Superior region were compared and contrasted. Factors structuring algal communities in each region were examined and similarities and differences were identified between the two regions. These regions were not found to support unique aerial algal communities. Third, bryophyte-algal associations were investigated from a cliff face in O’ahu, HI. Algal species were examined for fidelity to bryophyte species within this site. There was no relationship found between algal species and bryophyte species, however, there was a relationship between algal species and both aspect and light levels. Finally, desiccation tolerance of algal communities was studied through a laboratory experiment. Changes in algal community composition were examined after exposure to different periods of desiccation. Overall, algal community composition was not found to change as a result of exposure to different periods of desiccation. This dissertation explored algal communities from understudied aerial and explored factors that structure and influence community composition. iii DEDICATION To my son, Alexander, I am so excited to watch you and be there with you as you begin your own exploration of the world. iv ACKNOWLEDGMENTS First and foremost, I want to thank my husband, Evan Thomas, for his constant support and encouragement throughout this project. Not only did Evan provide much needed emotional support, but he also provided logistical support throughout the project. Evan was always ready to help me brainstorm, aid in fieldwork, and review my manuscripts time and time again. I also thank him for setting aside work on his own dissertation during the last year of my program to allow me more time to complete my work. Without his support and self-sacrifice, I would not have been able to complete this work. I also want to thank my parents, Robert and Judith Ress, for their support and encouragement throughout this process. I want to thank my advisor, Dr. Rex Lowe, for his guidance and support throughout my graduate career. I want to thank Rex for allowing me the independence to pursue and coordinate this project. Rex has helped me grow and develop as a researcher which has allowed me to become a more knowledgeable and confident scientist. I would also like to thanks my committee, Dr. George Bullerjahn, Dr. Jeff Johansen, Dr. Dan Pavuk, and Dr. John Chen, for their guidance and time. This work was funded in part by a Sigma Xi Grant-in-Aid of research. v TABLE OF CONTENTS Page INTRODUCTION: ALGAL COMMUNITIES FROM AERIAL HABITATS .................... 1 CHAPTER I. MORPHOLOGICAL ADAPTATIONS AND HABITAT PREFERENCE OF AERIAL DIATOMS Introduction.... ............................................................................................................ 6 Study Area........ ......................................................................................................... 8 Methods...................................................................................................................... 8 Results............ ............................................................................................................ 10 Cell Length..................................................................................................... 11 Biovolumes .................................................................................................... 12 Proportion Of Areolar Area ........................................................................... 13 Microhabitat Preference ................................................................................. 14 Discussion ...................................................................................................... 15 CHAPTER II. CONTRAST AND COMPARISON OF AERIAL ALGAL COMMUNITIES FROM TWO DISTINCT REGIONS Introduction.............. .................................................................................................. 19 Study Area...... ........................................................................................................... 20 Methods...................................................................................................................... 22 Results ........................................................................................................................ 23 Discussion............... ................................................................................................... 26 CHAPTER III. BRYOPHYTES AND ASSOCIATED ALGAL COMMUNITIES FROM AN EXPOSED CLIFF FACE ON O'AHU (HAWAI’I, USA) vi Introduction............. ................................................................................................... 30 Study Area........... ...................................................................................................... 31 Methods...................................................................................................................... 32 Results ........................................................................................................................ 33 Discussion................ .................................................................................................. 35 CHAPTER IV. DESICCATION TOLERANCE OF AQUATIC AND PSEUDOAERIAL ALGAE Introduction........... ..................................................................................................... 39 Study Area........ ......................................................................................................... 40 Methods...................................................................................................................... 41 Results..................... ................................................................................................... 43 Cell Density Data ........................................................................................... 43 Site 1 .................................................................................................. 45 Site 3 .................................................................................................. 45 Site 5 .................................................................................................. 46 Community Composition Data ...................................................................... 47 Site 1 .................................................................................................. 47 Site 3 .................................................................................................. 48 Site 5 .................................................................................................. 48 Non-Metric Multidimensional Scaling .......................................................... 49 Site 1 .................................................................................................. 49 Site 3 .................................................................................................. 49 Site 5 .................................................................................................. 50 vii Discussion................... ............................................................................................... 50 CONCLUSIONS AND FUTURE DIRECTIONS…............................................................. 54 LITERATURE CITED .......................................................................................................... 57 TABLES......................... ....................................................................................................... 64 CHAPTER I....... ........................................................................................................ 64 CHAPTER II... ........................................................................................................... 91 CHAPTER III. ........................................................................................................... 115 CHAPTER IV. ........................................................................................................... 122 FIGURES................... ........................................................................................................... 135 CHAPTER II... ........................................................................................................... 135 CHAPTER III. ........................................................................................................... 144 CHAPTER IV. ..........................................................................................................