Holocene palaeoenvironmental reconstruction based on fossil beetle faunas from the Altai-Xinjiang region, China Thesis submitted for the degree of Doctor of Philosophy at the University of London By Tianshu Zhang February 2018 Department of Geography, Royal Holloway, University of London Declaration of Authorship I Tianshu Zhang hereby declare that this thesis and the work presented in it is entirely my own. Where I have consulted the work of others, this is always clearly stated. Signed: Date: 25/02/2018 1 Abstract This project presents the results of the analysis of fossil beetle assemblages extracted from 71 samples from two peat profiles from the Halashazi Wetland in the southern Altai region of northwest China. The fossil assemblages allowed the reconstruction of local environments of the early (10,424 to 9500 cal. yr BP) and middle Holocene (6374 to 4378 cal. yr BP). In total, 54 Coleoptera taxa representing 44 genera and 14 families have been found, and 37 species have been identified, including a new species, Helophorus sinoglacialis. The majority of the fossil beetle species identified are today part of the Siberian fauna, and indicate cold steppe or tundra ecosystems. Based on the biogeographic affinities of the fossil faunas, it appears that the Altai Mountains served as dispersal corridor for cold-adapted (northern) beetle species during the Holocene. Quantified temperature estimates were made using the Mutual Climate Range (MCR) method. In addition, indicator beetle species (cold adapted species and bark beetles) have helped to identify both cold and warm intervals, and moisture conditions have been estimated on the basis of water associated species. Generally, the fossil beetle record indicates a cold and wet early Holocene (from ~10,424 to ~ 9500 cal. yr BP) and a relativly cold and dry middle Holocene (from ~6374 to ~ 4378 cal. yr BP) at the Halashazi Wetland. The appearance of bark beetle fossils (Phloeotribus spinulosus and Trypodendron sp.) clearly demonstrate the presence of trees at or very near the site around 9665, 9570 and 5451 cal. yr BP, whereas the spruce pollen values at the site never exceeded five percent, and there were no spruce macrofossils found in the palaeobotanical study. Using Quaternary beetles to reconstruct palaeoenvironments is a new research method for this region, and has never before been done in China. The project provides new evidence concerning the environmental history of the study area. This study has helped establish Quaternary beetle research in China, and has contributed to beetle faunal research in Eurasia. 2 Acknowledgements I am forever grateful to my supervisor, Professor Scott Elias, for his guidance, his words and deeds throughout my Ph.D program, as a great mentor and advisor. Without his encouragement and continual support, I would not have survived in this Ph.D program. Also, I express my sincere gratitude to his wife Nanette Elias, for the cakes, meals, and the family warmth in a foreign country. I am especially grateful to Dr. Robert Angus, who is retired from Royal Holloway, and now is a volunteer in Natural History Museum, London. He took me to the museum and helped me finish all the beetle identification work. Also, I express my appreciation to everyone who helped me with beetle species identifications, especially the staff of the Natural History Museum, who allowed access to their facilities and beetle specimens. I thank my advisors Professor Danielle Schreve and Dr. Ian Matthews, for their helpful suggestions about my research. I thank Professor Xingmin Meng from Lanzhou University, who provided the funds for my field work and radiocarbon dating. I thank China Scholarship Council for the generous support of my Ph.D study. I thank my parents for their support and love, and their company in my field work. I thank my wonderful husband, Jiang Wang, for his unconditional love and support. Thanks for showing up in my life and being my life partner. I thank Xuanyu Chen for being a great friend and housemate. He encouraged me all the time. Lastly, I thank the Geography Department of Royal Holloway for all their support. 3 Table of Contents Chapter 1. Introduction 1.1 Research Aims and Objectives…………………………………………………..………13 1.2 ResearchSignificance……………………………………………………………….……13 Chapter 2. Literture review 2.1 The development of Quaternary insect studies………………………………………..…14 2.2 Important features for beetles as palaeoenvironmental indicators……………………….21 2.2.1 Abundant species diversity and wide range of habitats…………………….….21 2.2.2 Species constancy in the Quaternary…………………………………………..21 2.2.3 Specific feeding habits…………………………………………………………23 2.2.4 Sensitivity to environmentalchange……………………………………………25 2.2.5 High mobility of beetles…………………………………………………..……26 2.3 The preservation of beetle fossils…………………………………………………..……28 2.4 Palaeoclimatic reconstructions using fossil beetles………………………………..….…30 2.4.1 The Mutual Climate Range method……………………………………………30 2.4.1.1 Limitations of the MCR method…………………………………………..…33 2.4.1.2 MCR Calibration…………………………………………………………..…34 2.4.1.3 Ubiquity Analysis……………………………………………………………37 2.4.2 The application of MCR in Late Pleistocene and early Holocene palaeoclimatic reconstructions……………………………………………………………..…39 2.5 Fossil beetles in archaeological research……………………………………………..…42 Chapter 3. Study area Study area and sampling site 3.1 Overview of the Study area – Chinese Altai region ………………….…………………45 3.2 Previous Holocene Studies in Altai region………………………………………………47 4 3.2.1 Holocene palaeoclimate reconstruction……………………………………..…47 3.2.2 Dominant atmospheric circulation…………………………………………..…50 3.3 Sampling sites……………………………………………………………………………57 3.4 Peat accumulation at Halashazi……………………………………………………….…59 3.5 Sampling procedures………………………………………………………….……….…60 3.6 Peat description …………………………………………………………….……...……62 3.7 Radiocarbon Dating ………..…………………………………………..……………..…65 Chapter 4. Methodology 4.1 Extraction of beetle fossils…………………………………………….…………….…..70 4.2 Identification…………………………………………………………………………..…70 4.2.1 Useful beetle exoskeleton parts for identification………………………......…70 4.2.2 Taxonomic literature…………………………………………………….…..…72 4.2.3 Images from websites……………………………………………………….…73 4.2.4 Museum Specimens……………………………………………………………73 4.3 Ecological statistics method…………………………………………………..…………75 4.4 Bugs Coleopteran Ecology Package (BugsCEP)…………………………………….......75 Chapter 5. Results 5.1 Identified fossil beetles…………………… ……………………..……………..…….…76 5.1.1 Species have been identified and their ecology and modern distribution .....…76 5.1.2 Taxa can only be identified to the genus or family level…………………..…119 5.2 Peat accumulation rates…………………………………………………………………130 5.3 The Mutual Climatic Range result …………..……………………………………....…132 5.3.1 MCR estimates for Profile one…………………………………………….…132 5.3.2 MCR estimates for Profile two…………………………………………….…135 5 5.3.3 Reasons for poorly constrained MCR estimates ………………………….…135 Chapter 6 Discussion 6.1 Ecological groups of beetles……………………………………………………………136 6.1.1 Analysis of the ecological groups for Profile One……………………………138 6.1.2 Analysis of the ecological groups for Profile Two……………………...……138 6.2 Insect taphonomy in peat deposits………………………………………………...……145 6.3 Palaeoenvironmental reconstruction……………………………………………………146 6.3.1 Early Holocene interpretation (Profile two: ~10,424 to ~9500 cal. yr BP)…..146 6.3.2 Middle Holocene interpretation (Profile one: 6374 to 4378 cal. yr BP)……...148 6.4 Comparison of the beetle record with other proxies……………………………………150 6.4.1 Studies from the Halashazi site………………………………………….……150 6.4.2 Studies from the Chinese Altai region and nearby area…………………...….158 6.5 Zoogeography…………………………………………………………………..………159 6.5.1 New distribution records…………………………………………………...…159 6.5.2 Altai Mountain range as a dispersal corridor…………………………………159 Chapter 7. Conclusions……………………………………………………………...…….161 Bibliography……………………………………………………………………………….164 Appendix 1………………………….……………….……………………………………..187 Appendix 2..………………………………………………………………………………..190 6 List of Figures Figure 1. Beetle food group…………………………………………….……………….….23 Figure 2. Hypothetical example of the overlap of climate envelopes for five species….….33 Figure 3. The results of tests of predicted versus observed TMAX and TMIN for predatory and scavenging species……………………………………………………………36 Figure 4. Ubiquity species climate envelopes for Bembidion lunatum...................................38 Figure 5. Species climate range of Amara alpine………………………………….………..39 Figure 6. MCR TMAX estimates for the British Late glacial………………………………40 Figure 7. Departures from modern mean July temperatures for sites in arctic Alaska…...…41 Figure 8. Location of Altai region…………………………………………………..………45 Figure 9. The Holocene study sites in the Chinese Altai region and the nearby areas…...…47 Figure 10. Overview map showing the palaeoclimatic study sites analyzed by Chen et al., 2008.…………………………………………………………………………...…51 Figure 11. The out-of-phase relationship of Holocene moisture evolution between monsoon Asia and ACA…………………………………………………………………....52 Figure 12. Comparison of the moisture index of Xinjiang Area with other indexes…….….53 Figure 13. Comparison of the interpreted Holocene environmental change from Narenxia Peat with NAO index and Carotenoid flux rate…………………………….……56 Figure 14. Peat hummocks in the Halashazi wetland……………………………………….57 Figure 15. The bedrock geology of the Chinese Altai Mountains…………………………..58 Figure 16. The distribution of vegetation from the Altai region……………………….……59 Figure 17. The topographic