University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 5-2018 Biogeochemistry of Sulfur in Small Forested Catchments of the Great Smoky Mountains National Park Adrian Miguel Gonzalez University of Tennessee, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Recommended Citation Gonzalez, Adrian Miguel, "Biogeochemistry of Sulfur in Small Forested Catchments of the Great Smoky Mountains National Park. " PhD diss., University of Tennessee, 2018. https://trace.tennessee.edu/utk_graddiss/4901 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Adrian Miguel Gonzalez entitled "Biogeochemistry of Sulfur in Small Forested Catchments of the Great Smoky Mountains National Park." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Civil Engineering. John S. Schwartz, Major Professor We have read this dissertation and recommend its acceptance: Michael E. Essington, Qiang He, Anna Szynkiewicz Accepted for the Council: Dixie L. Thompson Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) Biogeochemistry of Sulfur in Small Forested Catchments of the Great Smoky Mountains National Park A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville Adrian Miguel Gonzalez May 2018 Copyright © 2018 by Adrian Miguel Gonzalez All rights reserved. ii DEDICATION To the three women in my life who encourage, challenge and cheer me on to conquer on their behalf: Catherine, Elizabeth, and Nicole iii ACKNOWLEDGEMENTS This research was funded by the U.S. Department of Interior, Southern Appalachian Cooperative Ecosystems Studies Unit, CA No. P14AC00882, Task Agreement No. P14AC00867. Field activities were permitted by the U.S. Department of Interior National Park Service under permit No. GRSM-2016-SCI-1248, and soil sampling areas were checked for cultural or archeological artifacts by NPS archeologist. Special thanks go to Dr. John Schwartz for guiding my journey through this doctorate experience. I often told family and friends during my time in the program that there could not have been a better student-advisor fit for me. John too worked through his doctoral program in the middle-ages of life, so he more than most was well-equipped for understanding my perspective as a “late- bloomer” student. Not only did he provide excellent technical guidance, but his relaxed perspective on academia in the larger context of living life was very helpful and welcome. I hope that I can be the same to those with whom I collaborate in the future. I would also like to thank the other members of my committee for contributing to my experience and knowledge, both in and out of the classroom. Three of my favorite courses were taught by Dr. Anna Szynkiewicz and Dr. Michael Essington (Dr. “E”), which I tried to put to good use in this research, and my most challenging course was taught by Dr. Qiang He. Thanks also go to the National Park Service and the Great Smoky Mountains National Park, and specifically to Matt Kulp for his role in funding, contracts, and for the general research ideas regarding sulfur biogeochemistry in the Park. I had the honor of working beside numerous fellow students, some who provided much appreciated assistance in lab and field work, some who I gladly assisted and collaborated with in their iv programs, and some who just befriended the old guy in the lab for whom they had pity. It would be an effort to list everyone I worked with over the years; I’d forget some and leave them out. My support network on campus was only half of the community of people helped me get through this doctoral program in my late 40s/early 50s. They vicariously lived through the program with me, but I’m sure they were quite contented that it was me doing the work and not they! Special support came from my two daughters, Nicole and Elizabeth. Not only did they help with water sampling on occasion, but I shared the unique experience of being fellow college students together. Even more rare was the joy I got in being in the same UTK Civil Engineering department with Nicole during her junior and senior years. I am so grateful for the experiences of seeing her in class down the hall from the graduate student offices, having her gently knock on the window next to my cubicle to be let in for a quick visit, and walking to the Student Union together for a Chick- Fil-A lunch. It’s been such a blessing for me to share daily academic life with my grown daughter. I also have such gratitude and pride in being an inspiration to my other daughter Elizabeth in pursuing graduate education for herself. Perhaps she reasoned: “if my old man can do, this should be a piece of cake for me!” I especially enjoyed our conversations on academia or graduate studies or sharing advice on writing or navigating relationships with fellow students or professors. Lastly, special acknowledgement goes to my dearest wife and friend, Catherine. Such sacrifice from her to allow me to achieve this goal and bucket-list item! Amazing! Taking on roles of primary income earner and family-budget manager to keep expenses below our combined incomes of a non-profit employee and a student stipend! Showing grace and patience in being left alone for hours on end while I shuttled back to the lab to finish running samples or to the student offices to write! Thank you doesn’t come close to breaking even, but I’ll start there. I have the rest of our life together to work on paying it back. v ABSTRACT This dissertation presents three studies designed to investigate sources and biogeochemical processing of sulfur in the Great Smoky Mountains National Park (GRSM). First, a geochemical study of first- and second-order streams throughout the GRSM was conducted to determine variability in water quality and the influence of natural land disturbances on the water quality. The study identified three categories of sites, each with distinct water chemistry: lower elevation sites, high-elevation sites, and sites influence by sulfidic bedrock. Stream water chemistry was statistically significantly different in catchments with and without known areas of land disturbances that exposed sulfidic bedrock to the atmosphere. A second study focused on soil/stream water geochemistry and the influence of bedrock composition on it. Three sites overlying sulfidic bedrock were statistically compared to two overlying sandstone and two overlying a bedrock transition zone. Stream water from the two sites adjacent to exposed sulfidic bedrock had the lowest pH and acid-neutralizing capacity, the highest sulfate concentrations, as well as the highest metals and cations concentrations. Results also showed that the soil organic phase was the primary locus of sulfur retention in high-elevation forest catchments. The third study focused on stable isotope geochemistry in the same seven catchments. It showed that stream water chemistry, and the sulfur ( δ34 S) and oxygen ( δ18 O) isotope composition of stream water sulfate and soil sulfur, reflects atmospheric sulfate in the absence of significant sulfur/sulfate inputs from sulfidic bedrock. All three studies were consistent in providing evidence that influence of sulfidic bedrock on stream water geochemistry in high-elevation catchments is dependent on the bedrock’s exposure to the atmosphere. The soil mantel has a stronger direct influence on GRSM stream water chemistry than bedrock composition, as indicated by the sulfur and oxygen isotope composition of soil sulfur and soil organic sulfur and by the similarity in sulfur isotope composition of sulfate vi in stream water and subsurface soil. Geochemical indicators of acidification of GRSM stream water and soil at the selected study sites appear to be caused by the characteristically low- neutralizing potential of high-elevation soil than to the composition of underlying bedrock. vii PREFACE “Modern man has no real ‘value’ for the ocean [or the environment generally]. All he has is the most crass form of egoist, pragmatic value for it. He treats it as a ‘thing’ in the worst possible sense, to exploit it for the ‘good’ of man. The man who believes things are there only by chance cannot give things a real value. But for the Christian, the value of a thing is not in itself autonomously, but because God made it. It deserves this respect as something which was created by God, as man himself has been created by God. “So man has dominion over nature, but he uses it wrongly. The Christian is called upon to exhibit this dominion, but exhibit it rightly: treating the thing as having value in itself, exercising dominion without being destructive. “… what we should have, individually and corporately, is a situation where, on the basis of the work of Christ, Christianity is seen to be not just ‘pie in the sky,’ but something that has in it the possibility of substantial healings now in every area where there are divisions because of the Fall. First of all, my division from God is healed by justification, but then there must be the ‘existential reality’ of this, moment by moment; second, there is the psychological division of man from himself; third, the division of man from nature, and nature from nature.