Hull) Mphil (Cantab)

Thesis submitted for the degree of Doctor of Philosophy At the University of Leicester By William D. Gosling BSc (Hull) MPhil (Cantab) Department of Geography University of Leicester Submitted: December 2003 Examined: April 2004 © William This thesis is copyright material and no quotation from it may be published without proper UMI Number: U188605 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. Dissertation Publishing UMI U188605 Published by ProQuest LLC 2014. Copyright in the Dissertation held by the Author. Microform Edition © ProQuest LLC. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 Characterization of Neotropical forest and savannah ecosystems by their modern pollen spectra William D. Gosling Abstract Controversy surrounds the Quaternary palaeoenvironmental history of Amazonia. It is unclear whether moist evergreen forest, savannah or seasonally dry forest dominated the Amazon basin at the last glacial maximum (c. 21,000 years B.P.). In part the uncertainty surrounding the palaeoenvironmental history of Amazonia stems from a poor understanding of the ecological significance of the fossil pollen records from the region. In order to improve interpretations of the fossil pollen record it is essential to better understand the nature of the pollen rain produced by modem ecosystems. In this thesis, three Neotropical ecosystems equivalent to those alluded to above were characterised by their modem pollen rain. This was achieved by examining samples collected in artificial pollen traps located within permanent (50 x 200 m) vegetation plots in the Noel Kempff Mercado National Park area, Bolivia. In each plot 10 traps were sampled for one field season (September 1998 to September 1999, or September 2000 to September 2001) and 5 traps were sampled from two additional field seasons (between 1998 and 2001). Pollen counts of at least 100 grains were made for each trap. In total 318 pollen taxa were distinguished, of which 116 were identified. The characteristic pollen from each of the three ecosystems were determined through a series of steps: spatial and temporal variations were explored using Spearman’s Rank correlations, the distinctive taxa of each ecosystem were identified using Principal Components Analyses (PCA), and the representativity of the pollen for each ecosystem was examined by comparing pollen and vegetation abundances. These analyses revealed a small number of taxa that can be used to characterize these ecosystems. Further PCA showed that it is possible to differentiate between the ecosystems by assessing the relative proportions of Didymopanax, Alchornea, Anadenanthera , Melastomataceae/Combretaceae, Moraceae/Urticaceae, Myrtaceae, Palmae, Pteropsidia (trilete), Poaceae and Solanum. These findings mean that it is now possible to detect these ecosystems in the fossil pollen record and consequently further information regarding the nature of the vegetation change in the Amazon basin can be gained. i Acknowledgements First thanks must go to my two supervisors Dr Francis Mayle and Dr Nick Tate (both University of Leicester) who provided constructive and sometimes contrasting comment on the development of this research as well as support and encouragement throughout. Thanks must go to Rachel Burbridge who provided a model for how to complete a palynology based PhD in Leicester. Also, thanks everyone else at Leicester who has contributed to this project, namely: Dave Orme, Kate Moore, Ruth Pollington (all Geography), Gary Mullins, Dave Gesthorp, Andrew Swift (all Geology) and John Bailey (Biology). In addition, thanks to my examiners Dr Henry Lamb (The University of Wales, Aberystwyth) and Professor Andrew Millington (University of Leicester) for their comments and opinions, these will be invaluable in the forthcoming publications. I acknowledge the financial support from a University of Leicester studentship, field work funds from the British Ecological Society, the Royal Geographic Society (both obtained by F.E. Mayle) and the Quaternary Research Association, and money for the participation in international conferences from the British Ecological Society and the Quaternary Research Association. In addition it would have been impossible to carry out this research in the remote comer of Bolivia without local support and assistance. Key among the many who helped was Tim Killeen (Conservation International) who set up the vegetation study plots from which the modem pollen rain was collected. Logistical support is also acknowledged from those at the Museo de Historia Natural “Noel Kempff Mercado” in Santa Cruz, Bolivia, especially Mario Suarez Riglos, Mario Saldias and Nelson Rodriguez. Also, I would like to thank Belen / Acknowledgements Quezada R. and Lupita Sanchez for their help in the field and, of course, immense thanks must go to Marcelo ‘Machi’ Siles for his, and his families, assistance and unstinting hospitality during both my visits to Bolivia. Furthermore, this project would not have been possible without the expertise of our guides in the field Juan Surubi and Pastor Soliz who were able to locate the traps even when the GPS failed us! I would also like to express my gratitude to Chris Allison (‘Acordis’, Grimsby), Chris Brunsdon (University of Newcastle-upon-Tyne), Steve Boreham (University of Cambridge), Jane Bunting (University of Hull), Mark Bush (Florida Institute of Technology, USA), Alex Chepstow-Lusty (University of Montpellier, France), Louise Emmons (Smithsonian Institution, USA), Eric Grimm (Illinois State Museum, USA), Martin Head (University of Cambridge), Sheila Hicks (University of Oulu, Finland), Yadvinda Malhi (University of Edinburgh), Robert Marchant (University of Amsterdam), Phil Metcalfe (University of Swansea), Steve Panfil (Amazon Conservation Association, USA) and Surangi Punyasena (University of Chicago, USA) for useful and instructive comments and discussion at various stages of the project. Finally, I would like to thank my friends and family who have helped to keep me sane during the last three years and more. Especially thanks must go to Mum, Dad and Helen for always being there. Also, to all those who have shared accommodation with me: John, before we were burnt out of the Fishers, and all those at Welford Road - Alex, Bradders, Jen, Rich and Stephen. Tom, Charlie, Renata and Harry cat it certainly would not have been the same without you all. Jo thanks for the proof reading and for being there for me. iii I List of contents Volume 1 Abstract i Acknowledgements ii List of contents (volume 1) iv List of contents (volume 2) x List of figures xi List of tables xv List of equations xvii List of acronyms and abbreviations xviii List of plates xix Frontispiece Chapter 1: Introduction 1 1.1 Rationale and overall aim 2 1.2 Structure of thesis 4 Chapter 2: Understanding Amazonian palaeoenvironments 5 2.1 The study of palaeoenvironments 6 2.1.1 Future climate change 7 2.1.2 The Amazonian palaeoenvironmental record 9 2.1.3 Theories of vegetation change in Amazonia 10 2.1.4 Research agenda 16 2.2 Modern pollen-vegetation studies 17 2.2.1 Theory 17 iv List of contents 2.2.2 Modem pollen in the Neotropics 18 2.2.3 Focus on ecotones 20 2.3 Research aims 21 2.4 Summary 22 Chapter 3: Noel Kempff Mercado National Park, Bolivia 24 3.1 Park ecology 25 3.2 Park palaeoecology 30 3.3 Justification for using park 32 3.4 Summary 33 Chapter 4: Methodology 34 4.1 Field methods 35 4.2 The pollen trap 37 4.3 Laboratory methods 39 4.3.1 Extraction from viscose rayon staple 39 4.3.2 Separation of ‘washed’ sample from buchnar funnel filter paper(s) 40 4.3.3 Final treatment 41 4.3.4 Alternative laboratory method 41 4.4 Pollen analysis and identification 41 4.5 Sampling problem 42 4.6 Summary 43 Chapter 5: Pilot research 44 5.1 Preliminary investigation 45 List of contents 5.1.1 Strategy 46 5.1.2 Results 47 5.2 Detailed investigation of spatial variability 49 5.2.1 Strategy 50 5.2.2 Results 52 5.3 Strategy for main project 52 5.4 Summary 54 Chapter 6: Ecosystem ecology 55 6.1 Biogeographic context 56 6.1.1 Moist terra firma evergreen forest ecosystem 59 6.1.2 Deciduous and semi-deciduous dry forest ecosystem 60 6.1.3 Terra firma savannah ecosystem 62 6.2 Noel Kempff Mercado National Park ecosystem characteristics 64 6.2.1 Moist terra firma evergreen forest ecosystem 65 6.2.2 Deciduous and semi-deciduous dry forest ecosystem 67 6.2.3 Terra firma savannah ecosystem 69 6.3 Study plot ecology 70 6.3.1 Tall terra firma evergreen forest plant community 71 6.3.2 Semi-deciduous dry forest plant community 72 6.3.3 Cerradao plant community 74 6.4 Summary 75 Chapter 7: Ecosystem pollen signatures 78 7.1 Data and statistical techniques used 79 vi I List of contents 7.1.1 Intra-plot spatial variability 80 7.1.2 Inter-annual variability 81 7.1.3 Distinctive pollen taxa 81 7.1.4 Pollen-vegetation relationships 83 7.2 Tall terra firma evergreen forest 84 7.2.1 Intra-plot spatial variability 85 7.2.2 Inter-annual variability 90 7.2.3 Distinctive pollen taxa 94 7.2.4 Pollen-vegetation relationships 101 7.2.5 Tall terra firma evergreen forest pollen signature 104 7.3 Semi-deciduous dry forest 109 7.3.1 Intra-plot

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