Fire and Forest in the Highlands of the Cordillera Central, Dominican Republic : Modern Dynamics and Long-Term History
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University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 12-2003 Fire and forest in the highlands of the Cordillera Central, Dominican Republic : modern dynamics and long-term history Lisa Marie Kennedy Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Recommended Citation Kennedy, Lisa Marie, "Fire and forest in the highlands of the Cordillera Central, Dominican Republic : modern dynamics and long-term history. " PhD diss., University of Tennessee, 2003. https://trace.tennessee.edu/utk_graddiss/5146 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Lisa Marie Kennedy entitled "Fire and forest in the highlands of the Cordillera Central, Dominican Republic : modern dynamics and long-term history." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Geography. Sally P. Horn, Major Professor We have read this dissertation and recommend its acceptance: Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) To the Graduate Council: I am submitting herewith a dissertation written by Lisa Marie Kennedy entitled "Fire and Forest in the Highlands of the Cordillera Central, Dominican Republic: Modem Dynamics and Long-Term Ristory." I have examined the final paper copy of this dissertation forform and content and recommend that it be accepted in partial fulfillment of the requirements forthe degree of Doctor of Philosophy, with a major in Geography. We have read this dissertation and recommend its acceptance: �s: � -c�--- � 2---" "'=2.. Kenneth H. Orvis � I-fenri Grissino-Mayer ArthurD1cc�CWGv- C. Echtemacht " Accepted for the Council: .. ' • t • �' t . FIRE AND FOREST IN THE HIGHLANDSOF THE CORDILLERA CENTRAL, DOMINICAN REPUBLIC: MODERNDYNAMICS AND LONG-TERMHISTORY A Dissertation Presented forthe Doctor of Philosophy Degree The University of Tennessee, Knoxville Lisa MarieKennedy December 2003 ACKNOWLEDGEMENTS I wish to thankmy major professor,Dr. Sally Hom, andthe other members ofmy dissertation committee, Drs. Ken Orvis,Henri Grissino-Mayer, andA. C. (Sandy) Echtemacht, forguidance in conducting andpresenting my dissertation research. My graduateprogram under Dr. Hom's direction has been invaluable preparation formy academic career. My researchexperiences andcoursework with her andwith Dr. Orvis have especially shaped my ideas about biogeography,_ paleoecology, andother aspects of physicalgeography. My many"tours" as a fieldassistant on Dr. Hom's researchpr<?jects have pr!)videdme with valuable tropicalfield experience, along with countless extraordinarymemories forwhich I amgrateful. I amalso gratefulto the Departmentof Geographyat the Universityof Tennessee forproviding a high quality programand a supportive environment that promotes academic excellence. My dissertation researchon modem pollen-vegetation relationships (Chapters 2) and on the sedimentaryrecord froma bog in Valle de Bao (Chapter 3) was partof a largerstudy, fundedby grantsto S. Hom, K. Orvis,and M. Clarkfrom the National GeographicSociety and fromthe National Science Foundation (SBR-9809798). My fieldworkon postfirevegetation regeneration (Chapter 4) was supported by anNSF Doctoral Dissertation hnprovementgrant (BCS-9901080). Otherfield expeditions in the Dominicanhighlands that helped shape ideas forthis dissertation andprovided opportunities to collect initialdata were fundedby theTennessee Geographic Alliance (in partthrough a grantto Sid Jumper fromthe National GeographicSociety), and by two grantsfrom funds at the Universityof Tennessee: a grantto me fromthe W.K. McClure 11 Fund forthe Study of World Affairs, and a grant to Sally Hornand me fromthe Stewart K. McCroskey Memorial Fund in the Department of Geography. ManyDominicans have provided assistanceand logistical support. My trusted friend, SergeantJuan Rosado of the Dominicanarmed forces, kept us safeand .provided field assistanceand informal Spanishlessons on all of my excursionsto the Dominican highlands. Several Dominicanbotanists including Milciades Mejia andRicardo Garcia fromthe National Botanical Garden, SantoDomingo, and Angela Guerrero of Santo Domingo, assisted in the collection and/oridentification of plant specimens fromthe highlands. Walter Judd fromthe Universityof Florida identified Lyonia specimens. This work was carried out with assistance andsupport from the Moscoso Puello Foundation, a non-profit conservation group in the DominicanRepublic. I especially am gratefulto Andres Ferrer (formerdirector of the Moscoso Puello Foundation) fo�his innumerable contributionsto my work andfor his devotion to the study and conservation of the highlands. Several people provided field assistance. My graduatestudent colleagues Jim Speer and Marty Arford, along with a talented undergraduate, Katie Budzinski, and an energetic school teacher fromMontana, JannClaus, assisted me withmy modern vegetation research. Sally Horn,Ken Orvis,Mike Clark, Jim Speer, andAndy Walter assisted with the modernand fossil pollen fieldwork. My student colleagues at the University of Tennessee (some have now moved on) provided laboratory assistance, helpful discussion, advice, andmoral support. Roger Brown, Katie Budzinski, Rachel Clement, Duane Cozadd, Charles Lafon, Brandon League, and Jim Speer improved the work forthis project in various ways. My countless iii hours in the Paleoenvironmental ResearchLab were made much more enjoyable by MartyArford and Kevin Anchukaitis,who deservespecial mention forproviding not only researchassistance, but great friendship and a lot of laughs along the way. I also appreciate the work of Will Fontanez andthe University of Tennessee Cartographic Services Laboratory on the maps in this document. Many other friends and colleagues have offered assistance andencouragement along theway� Ken Newton (ProfessorEmeritus) andhis wifeMary of Knoxville have been like family, always urging me forwardand celebrating my accomplishments. I feel very fortunateto have received immeasurable support from my colleagues in the Department ofGeographyat Virginia Tech (faculty, staff, graduate students) during the writing of this dissertation. John and Stacy Boyer andDrs. Carolyn Copenheaver and Phil Radtke (all of Virginia Tech), Deborah De (RadfordUniversity), and Cathy Luthman Roberts (IndianaUniversity-Purdue University, Indianapolis)provided special friendship, professionalassistance, andmotivation. And finally, I owe special thanksto my long time friendCindy Sterling, andmy family,especially my mother Loretta Kennedy and my sister Pam Franklin, forunending patience andunconditional supportover the entire course of my graduatework. IV ABSTRACT This dissertation investigates past andpresent environments ofthe highlandsof the Dominican Republic using paleoecological andmodem ecological techniques. The relatively unstudied highlands (>2000 m) of the Cordillera Central are blanketed by a mosaic of pine forests,open pine woodlands,and grasslands, with broadleaf tr�es joining the canopyin sheltered locations. My researchon modem vegetation andfire ecology, and on long-t� fireand vegetation history, helps fillgaps in the knowledgeof Caribbeanenvironments, andmay assist landmanagers in conservation effortsin the Dominicanhighlands. A study of the relationship between modem pollen rain andvegetation cover in the highlands provided a basis forinterpreting pollen assemblages in sediment profiles. As expected, pine pollen dominated most samples. DetrendedCorrespondence Analysis indicated that the modem pollen spectraof foresteduplands and open wetlandsites are clearly distinct, while a variety of other site types that areintermediate in termsof vegetation are also intermediatein terms of modem pollen spectra. Forested sites were widely dispersed, while intermediatesites andwetlands were more tightlyclustered, indicating greatersimilarity in pollen spectra of those sites. Lack of pine stomata was an excellent indicator of treelessness. The distinction between forested andnon-forested sites may be usefulin interpreting highlandfossil records that may reach back into the last glacial period. Analysis of a 126.5 cm sediment core froma bog in Valle de Bao on the windwardslope of the Cordillera Central indicated that disturbancesby fire,tropical storms,and climatic fluctuationshave been partof the highland ecosystem formillennia. V The bog formed during a relatively moist period around 4000 yr BP. The record includes strongsignals of dry periods during the late Holocene, and matches some trendsin a sediment record from Lake Miragoane, Haiti, nearsea level. A study ofpostfireregeneration of pines and shrubs at five recently burnedsites provided evid�nce that the woody vegetation of the pine-forestedhighlands is well adapted to fire. Most shrubs at all sites resprouted fromtheir bases, andin one site, shrubsregained prefirestem heightswithin seven years. Recovery of shrub stein .diameterslagged behind. Largepines can survive