Western University Scholarship@Western Electronic Thesis and Dissertation Repository 6-26-2020 10:00 AM Determining geological controls on nutrient availability at different depths in the soils of the Pelee Island Winery Lindsay M. Blythe, The University of Western Ontario Supervisor: Webb, Elizabeth, The University of Western Ontario Joint Supervisor: Corcoran, Patricia, The University of Western Ontario A thesis submitted in partial fulfillment of the equirr ements for the Master of Science degree in Geology © Lindsay M. Blythe 2020 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the Geochemistry Commons, Geology Commons, and the Soil Science Commons Recommended Citation Blythe, Lindsay M., "Determining geological controls on nutrient availability at different depths in the soils of the Pelee Island Winery" (2020). Electronic Thesis and Dissertation Repository. 7105. https://ir.lib.uwo.ca/etd/7105 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. Abstract Terroir describes a sense of place that can give a unique flavour to wines grown in different environments. We explored the role of soil in the terroir at Canada’s most southern vineyard, Pelee Island Winery. This study examined the abundance of major nutrients, trace and rare earth elements of minerals and plant extractable nutrients from 19 soils across the vineyard to a depth of 2 m. We found that bedrock does not influence the element content of Pelee Island soils, the parent materials of the soils are tills and there are geochemical, mineralogical and grain size differences between the two soil types on the island. Nutrient distribution throughout the soil profile was controlled by soil weathering with organic matter concentrating most nutrients in surface soils. Agricultural and anthropogenic influences had minimal effects on soil nutrient concentrations. Keywords Pelee Island, winery, vineyard, terroir, Brookston, Toledo, soil geochemistry, bioavailability, pedogenesis, plant extractable nutrients ii Summary for Lay Audience Pelee Island is the southernmost point and has the longest growing season in Canada making it an ideal place to grow grapes to produce quality wines. We examined the elemental concentrations of the soil minerals and nutrients in the soils easily mobilized by plants (plant extractable nutrients) in order to understand variations in grape productivity across the island. This work will lead to a better understanding of how the soil contributes to the terroir, or sense of place that contributes to the flavours of Pelee Island wines. The aims of this study were to determine if bedrock has any influence on soil composition, to distinguish geochemical differences between the two main soil types on the island – Brookston and Toledo, and to understand how soils processes and agricultural and anthropogenic influences affect nutrient distribution within the soil profiles across Pelee Island. Results from the geochemical analysis conclude a few important findings. First, bedrock does not influence the composition of Pelee Island soils. Second, weathering intensities between Brookston and Toledo soils differ causing differences in elemental distributions throughout their soil profiles. Brookston soils are shallower and less leached resulting in higher abundance of Ca in surface soils and lower abundances of Fe and Mn in deep soils compared to Toledo soils. Third, nutrients used by plants are generally highest in surface soils where they are held by organic matter. Lastly, anthropogenic (i.e. airborne pollutants) and agricultural (i.e. fertilizers) influences had minimal effects on soil nutrient concentrations. These results will enable Pelee Island Winery to enhance their soil management practices and improve grape quality to produce quality wines. iii List of Abbreviations CEC Cation exchange capacity DTPA Diethylene triamine penta-acetic acid EDTA Ethylene diamine tetra-acid LOI Loss on ignition MMI Mobile metal ion NASC North American shale composite PEN Plant extractable nutrients PCA Principle component analysis REE Rare earth element UAN Urea ammonium nitrate XRD X-ray diffraction XRF X-ray fluorescence iv Co-Authorship Statement I declare that I am the sole author of this thesis and all work included is original. Dr. Elizabeth Webb and Dr. Patricia Corcoran devised and directed the project and acted as editors of all written work and advisors on data presentation and interpretation. Dr. Gerhard Pratt and Jacob Kukovica performed the Pelee Island seismic survey and complied the data into a report that is included in an appendix at the end of the thesis. Dr. Mark Biesinger set up and performed the principal component analysis used to make graphs and interpretations in the discussion chapter. v Acknowledgments I am very thankful to everyone who has helped in the completion of this project over the past two years. I would first like to thank my supervisors Dr. Elizabeth Webb and Dr. Patricia Corcoran for their tremendous support, guidance, and words of encouragement throughout this process. Their investment in me as a developing earth scientist is much appreciated and has allowed me to work towards both my professional and personal goals. Thank you to Patricia for not letting me forget the value of a list, of taking things one step at a time, and for her thorough editing of the final product. Thank you to Liz for the countless hours she has dedicated towards mentorship and editing. Her unwavering support throughout this experience has given me the confidence to see this process through to the end, and she has taught me that the hardest part is just getting started. This project would also not have been possible without the support of our industry and university collaborators. This project was funded by the Pelee Island Winery, NSERC CRD grant and the J. Malcom Slack Earth Sciences Award. Thanks to Jon Jacobs and Kimberly Law for their lab assistance, and to Bruno Friesen for his help in the field and for graciously providing lunches and fine wines. Thanks also to the staff at Pelee Island Winery for their help in soil collection and for coordinating field transportation, and my lab mates Zhaoming Jang and Ramen Tolo for their help in the field. Your positive attitudes and willingness to help made field work an enjoyable experience! Thanks also to those people who offered their time to aid in the data analysis for this project. Thanks to Dr. Gerhard Pratt and Jacob Kukovika for setting up the seismic survey and compiling data into a geophysical report. I am also grateful to Mark Biesinger for his help processing and interpreting PCA data. His help with the visualization an interpretation of my data was a major break-through for this project and I greatly appreciated his input. Thanks to my friends and colleagues in the Earth Science department for helping me navigate grad school and for reminding me to enjoy my time as a grad student. Lastly to my parents Joe and Audrey and my sisters Jennifer and Meghan Blythe for their love and encouragement over the past two years. Their endless support will never go unnoticed or unappreciated, and I am very grateful for everything they do and continue to do to support me. vi Table of Contents Abstract ............................................................................................................................... ii Summary for Lay Audience ............................................................................................... iii List of Abbreviations ........................................................................................................ ivi Co-Authroship Statement.................................................................................................... v Acknowledgements ............................................................................................................ vi Table of Contents .............................................................................................................. vii List of Tables ..................................................................................................................... xi List of Figures .................................................................................................................. xiii List of Appendices .......................................................................................................... xvii Chapter 1 ............................................................................................................................. 1 1 Introduction .................................................................................................................... 1 1.1 Literature Review.................................................................................................... 1 1.2 Background ............................................................................................................. 5 1.2.1 Geological History of Pelee Island ............................................................. 5 1.2.2 Glacial History of Pelee Island ................................................................... 8 1.3 Soil Formation Processes ...................................................................................... 11 1.3.1 Weathering ...............................................................................................