Investigating regeneration in a raised ombrotrophic bog after peat extraction by Kathryn Wiese B.Sc., University of Victoria, 2015 Project Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Ecological Restoration Program Faculty of Environment (Simon Fraser University) and School of Construction and the Environment (British Columbia Institute of Technology) © Kathryn Wiese 2019 SIMON FRASER UNIVERSITY BRITISH COLUMBIA INSTITUTE OF TECHNOLOGY Spring 2019 Copyright in this work rests with the author. Please ensure that any reproduction or re-use is done in accordance with the relevant national copyright legislation. Approval Name: Kathryn Wiese Degree: Master of Science Title: Investigating regeneration in a raised ombrotrophic bog after peat extraction Examining Committee: Ken Ashley Supervisor and Chair Faculty, British Columbia Institute of Technology Anayansi Cohen-Fernandez Internal Examiner Faculty, British Columbia Institute of Technology Douglas Ransome Internal Examiner Faculty, British Columbia Institute of Technology Date Defended/Approved: April 12, 2019 ii Abstract Burns Bog is a raised ombrotrophic bog in Delta, British Columbia and faced with myriad disturbances. This study is focused on the impact and restoration of peat extraction by the Atkins-Durbrow Hydropeat method. Depth to water table, relative abundance and distribution of vegetation, and the degree of peat decomposition at consistent-depth intervals were investigated to elucidate the status of passive and active ecological restoration in three fields previously harvested for peat approximately one decade apart and compared to a fourth unharvested field. Summary statistics, Redundancy Analysis, and regression were used to compare restoration status and trends in hydrology, vegetation composition, and peat accumulation. A lag period between cessation of harvest and implementation of restoration, coupled with rapid anthropogenic climate change, serve as impediments to restoration here. Intervention in the form of improved rainfall retention, assisted recolonization, and the introduction of nurse species are recommended to improve bog function and resiliency. Keywords: Atkins-Durbrow Hydropeat method; Burns Bog; ditch blocking; ecological restoration; peat extraction; raised ombrotrophic bog iii Acknowledgements I would like to thank all who supported me in this research because in their absence it would not have been possible. Thank you to Dr. Ken Ashley (BCIT) and Dr. Sarah Howie (Delta) for their supervision. Thank you to the City of Delta, Metro Vancouver, and the Burns Bog Scientific Advisory Panel for enabling this research. Thank you to Thomas Munson for passing on his bog vegetation identification skills. Thank you to Joe Soluri (Metro Vancouver) for his assistance in finding my field sites, hidden behind thickets of Himalayan blackberry. Thank you to Dr. Ruth Joy (SFU) for her technical assistance in R. Thank you to Ian Bercovitz (SFU) for his technical advice in JMP. Thank you to my friends, family, and colleagues for their support and encouragement. Finally, I would like to express my gratitude to my whole field team for their time, effort, and enthusiasm. iv Table of Contents Approval .......................................................................................................................... ii Abstract .......................................................................................................................... iii Acknowledgements ........................................................................................................ iv Table of Contents ............................................................................................................ v List of Tables ................................................................................................................. vii List of Figures................................................................................................................viii List of Acronyms .............................................................................................................. x Glossary ......................................................................................................................... xi Introduction ................................................................................................................... 1 Overview ......................................................................................................................... 1 Carbon Sequestration .................................................................................................. 5 Drainage and Peat Extraction .......................................................................................... 6 Restoration of Raised Bogs ............................................................................................. 8 Restoration Efforts in Burns Bog .................................................................................. 9 Additional Threats to Burns Bog .................................................................................... 10 Vegetation ..................................................................................................................... 12 Ecosystem Services ...................................................................................................... 13 Research Objectives ..................................................................................................... 15 Methods ....................................................................................................................... 17 Study Area .................................................................................................................... 17 Study Site Selection ...................................................................................................... 19 Depth to Water Table .................................................................................................... 20 Vegetation ..................................................................................................................... 21 Peat Humification .......................................................................................................... 22 Statistical Analysis......................................................................................................... 23 Results ......................................................................................................................... 25 Hydrology ...................................................................................................................... 25 Vegetation ..................................................................................................................... 29 Clustering Analysis .................................................................................................... 34 Hierarchical Clustering Analysis ............................................................................. 34 K Means Clustering Analysis .................................................................................. 36 Peat Humification .......................................................................................................... 38 Microtopography ........................................................................................................... 41 Influence of Environmental Variables ............................................................................ 41 Discussion ................................................................................................................... 48 Hydrology ...................................................................................................................... 49 Influence of Depth to Water Table on Greenhouse Gas Emissions ............................ 53 Vegetation ..................................................................................................................... 54 Sphagnum Distribution............................................................................................... 59 v Aquatic Sphagnum ................................................................................................. 62 Nurse Species ........................................................................................................... 65 Peat Humification .......................................................................................................... 66 Microtopography ........................................................................................................... 70 Climate Change ............................................................................................................ 73 Study Limitations ........................................................................................................... 76 Reference Site Limitations ......................................................................................... 76 Recommendations for Restoration and Future Research .............................................. 78 References ................................................................................................................... 84 Appendix. Supplemental Tables and Charts ........................................................ 95 vi List of Tables Table 1. Depth to water table measurements collected at Burns Bog in July 2018 using City of Delta’s shallow piezometers............................................... 28 Table