ASSESSING THE IMPACTS OF LAND-USE AND CLIMATE CHANGE FOR WATER RESOURCE MANAGEMENT BY Copyright 2015 LINDSEY MARIE WITTHAUS YASARER Submitted to the graduate degree program in Civil, Environmental and Architectural Engineering and the Graduate Faculty of the University of Kansas in partial fulfillment of the requirements for the degree of Doctor of Philosophy. _____________________________ Chairperson Dr. Belinda SM Sturm _____________________________ Dr. Edward Peltier _____________________________ Dr. Bryan Young _____________________________ Dr. Val Smith _____________________________ Dr. Jerry deNoyelles _____________________________ Dr. Stacey Swearingen White Date Defended: May 12, 2015 The Dissertation Committee for Lindsey MW Yasarer certifies that this is the approved version of the following dissertation: ASSESSING THE IMPACTS OF LAND-USE AND CLIMATE CHANGE FOR WATER RESOURCE MANAGEMENT _____________________________ Chairperson Dr. Belinda SM Sturm Date approved: ii Abstract Sustainable management of water resources is a challenging interdisciplinary problem requiring the integration of fields such as hydrology, ecology, sociology, and public policy. In the past decade, there has been a great effort to understand how issues such as climate change and land-use change for biofuel feedstock production will affect water resources. This dissertation assesses the impacts of climate change and land-use change for water resource management in Kansas using an interdisciplinary approach and tools such as the Soil and Water Assessment Tool (SWAT), social surveys, and geospatial analysis. The SWAT model is used to simulate corn and grain sorghum biofuel-based land-use scenarios to assess water quality impacts and sustainability indicators in the Perry Lake and the Kanopolis Lake watersheds in Kansas. Modeling results suggest that corn scenarios produced significantly greater water quality impacts than grain sorghum scenarios, but that corn had a much higher crop yield, particularly in the Perry Lake watershed, and thus can provide more ethanol production potential per land, water, and nutrient input, which are efficiency metrics often used in agricultural studies. Overall, grain sorghum may be a more sustainable feedstock crop in drier climates and corn may be more sustainable in wetter climates. The sustainability measures utilized in this study allow for comparison between crops and between watersheds, yet they are typically not included in the current biofuel-based land-use analyses. This study shows the potential of integrating water quality analysis with sustainability indicators to develop a richer assessment of the trade-offs and benefits of landscape change for biofuel feedstock development. The impact of climate change was assessed in three ways: first, with a review of the potential climate change impacts for reservoirs and a discussion of the potential in-lake and iii watershed management strategies for mitigation; second, with a social survey that explores perceptions of Kansas water managers towards climate change and planning for climate impacts; and third, with a study of the influence of reservoir management on greenhouse gas emissions from a tributary of the Three Gorges Reservoir in China. The review of climate change impacts for reservoirs found that the sustainability of reservoir services will be threatened by climate change, but that there are a variety of management tools that may be able to mitigate impacts. The social survey demonstrated that anthropogenic climate change is a contentious issue within the state of Kansas, but that water managers believe it is important to consider future climate change in their planning efforts. Survey results, along with a review of key Kansas water management plans, suggest that Kansas water managers are indeed responsive to climate variability and are starting to integrate climate variability into planning efforts. The study of reservoir greenhouse gas emissions suggest that both CO2 and CH4 fluxes were influenced by reservoir water level and exhibited distinct patterns that correspond to the reservoir operation cycle. Over 90% of CO2 effluxes occurred during the high water period, whereas the 58% of CH4 effluxes occurred during the low water period. Results suggest that reservoir operations altered the hydraulic retention time, which along with water temperature, controlled the synthesis and decomposition of carbon in the backwater system. iv Acknowledgements This research was developed and supported through the generous support of several fellowships and NSF-sponsored programs: the NSF C-CHANGE (Climate Change, Humans, and Nature in the Global Environment) IGERT Fellowship, the NSF Graduate Teaching Fellowship in K-12 Education, the Kansas NSF EPSCoR Program, and the NSF EAPSI Fellowship. All of these programs have been instrumental in my development as an environmental scientist and professional and I am deeply thankful and humbled by this support. In addition, I would like to thank the following organizations for their financial contributions and support: the KU Transportation Research Institute, the Office of Graduate Studies, and the Department of Civil, Environmental and Architectural Engineering Department. Next, I would like to thank all of those who contributed their time, data, and/or knowledge to help me succeed in completing this dissertation. Thank you to Susan Metzger and all the staff at the Kansas Water Office who welcomed me into their office during a semester internship in 2012. Metzger was instrumental in helping me finalize the survey instrument utilized in chapter 5. Thanks to Jude Kastens and Dana Peterson who were extremely helpful in regards to accessing and utilizing GIS data and providing useful ArcGIS tips and guidance. I especially would like to thank Sumathy Sinnathamby, a valued colleague and friend, who provided both technical and emotional support throughout my PhD. In particular, Sumathy helped guide me through building my first SWAT model and was a key collaborator in the SWAT research, performing flow and crop calibration on the SWAT models used in this study. I would also like to thank Dr. Kyle Douglas-Mankin, as well as Dr. Aleksey Sheshukov at Kansas State University who provided helpful guidance on SWAT modeling. I am also grateful to support from Dr. Dietrich Earnhart, who led the Biofuels and Climate Change: Farmers’ Land- v Use Decisions, or BACC: FLUD team. In addition, I am thankful to Dr. Zhe Li for collaborating with me on the NSF EAPSI proposal and for hosting me for 8 weeks in Chongqing, China. Dr. Li and his students, especially Zhang Ping, were wonderful hosts and allowed me to have a productive and enjoyable time while in China. Also thanks to CSTEC who covered my living expenses while in China. I would also like to thank all my committee members for their mentorship and guidance: Drs. Edward Peltier, Bryan Young, Val Smith, Jerry deNoyelles, and Stacey Swearingen White. I have enjoyed all the conversations and collaboration with you all throughout my time at KU. Special thanks to Val Smith for investing his time to teach me about limnology and aquatic ecology. Also, thank you to Stacey for her help developing the social survey used in this dissertation and for encouragement and guidance as I transitioned onto the job market. I especially would like to thank my advisor, Dr. Belinda Sturm. She has been unflagging in her support, encouragement, and understanding as I rode the waves of life up and down over the past 5 years. Thank you for your guidance and the many hours spent brainstorming, reviewing manuscripts and presentations, and reading this dissertation! Finally, I would like to express my gratitude for my family. I will always cherish these years in Lawrence close to my family. To my parents, James and Marlene Witthaus, thank you for encouraging me to stay in Kansas - I will always recognize the role you played in that decision. Thank you for your unconditional support and love. To my husband, Hakan Yasarer, I am so grateful for you. Thank you for bringing so much joy and love into my life and standing by me in the most difficult times. You always remind me of my goals when I get distracted, and you encourage me to be a better person, every day. Without your support this dissertation would not have been possible. vi Table of Contents Abstract .................................................................................................................................................... iii Acknowledgements ................................................................................................................................... v Table of Contents .................................................................................................................................... vii List of Figures ........................................................................................................................................ xiii List of Tables ....................................................................................................................................... xviii Chapter 1 – Introduction ............................................................................................................................. 21 1.1 General Background ......................................................................................................................... 21 1.2 Ecohydrological Modeling for Sustainability Studies .....................................................................