The Consequences of Buffelgrass Pasture Development for Biodiversity in the Southern Sonoran Desert Item Type text; Electronic Dissertation Authors Franklin, Kimberly Anne Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 24/09/2021 13:06:37 Link to Item http://hdl.handle.net/10150/195818 THE CONSEQUENCES OF BUFFELGRASS PASTURE DEVELOPMENT FOR BIODIVERSITY IN THE SOUTHERN SONORAN DESERT by Kimberly Anne Franklin _____________________ A Dissertation Submitted to the Faculty of the GRADUATE INTERDISCIPLINARY PROGRAM IN INSECT SCIENCE In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 2009 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Dissertation Committee, we certify that we have read the dissertation prepared by Kimberly Franklin entitled The Consequences of Buffelgrass Pasture Development for Biodiversity in the Southern Sonoran Desert and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy ____________________________________________________________Date: 5/1/09 Therese Markow ____________________________________________________________Date: 5/1/09 Fransciso Molina-Freaner ___________________________________________________________Date: 5/1/09 Stuart Marsh ___________________________________________________________Date: 5/1/09 Yves Carriere ___________________________________________________________Date: 5/1/09 Diana Wheeler Final approval and acceptance of this dissertation is contingent upon the candidate's submission of the final copies of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. ____________________________________________________________Date: 5/1/09 Dissertation Director: Therese Markow 3 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at the University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his or her judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED: Kimberly Anne Franklin 4 ACKNOWLEDGEMENTS I would like to thank my advisor Therese Markow, who introduced me to the beautiful state of Sonora, Mexico and encouraged me to apply for funding to work internationally. Perhaps most importantly, she introduced me to her friend Francisco Molina-Freaner, whom essentially has served as a co-advisor to me for the past four years and has become a dear friend. His enormous generosity enabled me to pursue an ambitious research agenda in Sonora. I would also like to thank José Martinez Rodriguez, Jechu, my trusted field companion. I don’t know that I have ever encountered an individual with a work ethic as admirable as that of Jechu. Without his willingness to accompany me day after day in the field during the grueling Sonoran summers, I would not have been able to accomplish this work. Sharon Richards deserves so many thanks for always going far beyond the call of duty simply to make the lives of the Insect Science students that much easier, and I am indebted to Wendy Moore for her support and guidance in the beginnings of my graduate career, without which I would have been lost! Finally, I would like to thank Rick Brusca for inspiring me to pursue a career in conservation biology and helping me on my way, hopefully to follow in his footsteps and contribute to the preservation of the uniquely beautiful and still wild landscapes of Sonora, Mexico. 5 TABLE OF CONTENTS ACKNOWLEDGEMENTS ............................................................................................................................... 4 ABSTRACT.......................................................................................................................................................... 6 INTRODUCTION ............................................................................................................................................... 8 An explanation of the problem and review of the literature .......................................................................... 8 An explanation of the dissertation format....................................................................................................... 9 PRESENT STUDY ............................................................................................................................................ 11 REFERENCES...................................................................................................................................................13 APPENDIX A - BUFFELGRASS (PENNISETUM CILIARE) LAND CONVERSION AND PRODUCTIVITY IN THE PLAINS OF SONORA, MEXICO................................................................. 14 Abstract ...........................................................................................................................................................16 Materials and Methods................................................................................................................................... 20 Results..............................................................................................................................................................26 Discussion .......................................................................................................................................................30 References .......................................................................................................................................................35 APPENDIX B - THE CONSEQUENCES OF PASTURE DEVELOPMENT FOR PLANT DIVERSITY IN THE DRYLANDS OF NORTHERN MEXICO .............................................................51 Abstract ...........................................................................................................................................................53 Introduction.....................................................................................................................................................54 Methods ...........................................................................................................................................................59 Results..............................................................................................................................................................64 Discussion .......................................................................................................................................................67 Conclusion.......................................................................................................................................................74 References .......................................................................................................................................................75 APPENDIX C - THE EFFECTS OF LAND USE CHANGE AND PRODUCTIVITY ON ANT ASSEMBLAGES IN THE SOUTHERN SONORAN DESERT................................................................91 Abstract ...........................................................................................................................................................93 Methods ...........................................................................................................................................................98 Results............................................................................................................................................................106 Discussion .....................................................................................................................................................111 References .....................................................................................................................................................123 6 ABSTRACT Decades of overgrazing have left many rangelands in northwestern Mexico in poor condition. This has led to the practice of converting native rangeland plant communities to buffelgrass pastures. Buffelgrass (Pennisetum ciliare) is a perennial bunchgrass native to Africa. Both the extent of buffelgrass pastures within Mexico and the impacts of land conversion on biodiversity and ecosystem functioning. In the present study I address the effects of land conversion on the productivity and diversity of rangelands in the southern Sonoran Desert in the state of Sonora, Mexico. First, using satellite imagery from the Landsat mission, I found that rates of land conversion in the most heavily affected region of Sonora have continued to accelerate