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CHANNEL MORPHOLOGY, SUBSTRATE VARIABILITY, AND BEDROCK INFLUENCE IN THE JAMES RIVER, SOUTHWEST MISSOURI OZARKS A Masters Thesis Presented to The Graduate College of Missouri State University In Partial Fulfillment Of the Requirements for the Degree Master of Science, Geospatial Sciences in Geography and Geology By Andrew Robert DeWitt May 2012 CHANNEL MORPHOLOGY, SUBSTRATE VARIABILITY, AND BEDROCK INFLUENCE IN THE JAMES RIVER, SOUTHWEST MISSOURI OZARKS Geography, Geology, and Planning Missouri State University, May 2012 Master of Science Andrew Robert DeWitt ABSTRACT Channel morphology equations (CMEs) quantify downstream trends in channel variables and are useful for planning stream restoration designs and comparing river geomorphology among various regions. In the Ozarks, few studies exist that quantify stream characteristics, and a watershed-scale geomorphic study of rivers in southwest Missouri is currently lacking. The purpose of this research is to use CMEs to quantify channel form, substrate variability, and valley scale characteristics in the James River basin (3,771 km2). Specifically, the objectives are to: (1) quantify bankfull and longitudinal channel characteristics using channel form, substrate, and geospatial measurements coupled with USGS gage calibration; (2) develop channel morphology and stream power equations and evaluate sampling error and natural geomorphic variability; and (3) examine the influence of geologic controls on channel form and stream power. Field data were collected and analyzed from 17 sites along the main stem of the James River spanning a range of drainage areas from 6 to 2,530 km2. Results indicate bankfull channels in the James River contain the 1.1 to 1.5 year recurrence interval flood. Channel variables are strongly related to drainage area with r2 values >0.90 for equations describing cross-sectional area, discharge, depth, riffle spacing, and pool length. Poorly fitting equations for other variables are explained by variable influence of bedrock controls. Median sediment size slightly increases downstream due to tributary and bluff sediment inputs and non-linear downstream stream power trends. The CMEs produced by this research are useful for restoration designs and provide a base from which to further quantify channel forms and processes in the Ozarks. KEYWORDS: Ozarks river, channel morphology, bankfull, restoration, bedrock control This abstract is approved as to form and content Robert T. Pavlowsky Chairperson, Advisory Committee Missouri State University ii CHANNEL MORPHOLOGY, SUBSTRATE VARIABILITY, AND BEDROCK INFLUENCE IN THE JAMES RIVER, SOUTHWEST MISSOURI OZARKS By Andrew Robert DeWitt A Masters Thesis Submitted to the Graduate College Of Missouri State University In Partial Fulfillment of the Requirements For the Degree of Master of Science, Geospatial Sciences in Geography and Geology May 2012 Approved: Robert T. Pavlowsky PhD Douglas Gouzie PhD Jun Luo PhD _______________________________________ Pawan Kahol, Interim Graduate College Dean iii ACKNOWLEDGEMENTS Numerous people assisted and supported me throughout this research and without their helping hands this thesis would not have been possible. I would first like to thank Dr. Bob Pavlowsky for accepting me into the program, advising me throughout this process, and always having an open door. Dr. Pavlowsky taught me more than just fluvial geomorphology, but how to think and work like a dedicated scientist. I would like to thank committee members Dr. Douglas Gouzie and Dr. Jun Luo for their guidance and technical advice as well. Thanks goes to Marc Owen of the Ozarks Environmental and Water Resources Institute (OEWRI) for his assistance in site selections, field work, and for his technical expertise. I appreciate the field assistance from graduate students Megan Harrington, Kyle Kosovich, Anna Larkin, Ben Young, and the students of Dr. Pavlowsky’s summer (2011) graduate field class. I’m also grateful for river access provided by numerous land owners on the James River. Funding for my MS degree came from a Research Assistantship provided by OEWRI and the Graduate College. OEWRI also supplied the necessary field equipment and software used in this research. Funding to present research findings at many professional meetings came from the Graduate College, the College of Natural and Applied Sciences, the Department of Geography, Geology, and Planning, OEWRI, the Watershed Committee of the Ozarks, and professional organizations AAG and GSA. Last but not least I thank my wife, Dana, for her assistance in the field and for her loving encouragement and support throughout this process. I also appreciate the great support and uplifting words from friends and family in Michigan. To all of those mentioned and those I may have left out, I appreciate all you have done for me. Thanks. iv TABLE OF CONTENTS Chapter 1. Introduction ........................................................................................................1 Channel Morphology Equations ...............................................................................3 Bankfull Channel Concept ........................................................................................4 Stream Power ............................................................................................................6 Geologic Controls on Channel Morphology .............................................................7 Purpose and Objectives .............................................................................................9 Ozarks River Geomorphology ................................................................................11 Chapter 2. Study Area ........................................................................................................16 Geology ...................................................................................................................18 Climate and Hydrology ...........................................................................................20 Land Use .................................................................................................................21 Chapter 3. Methods ............................................................................................................23 Site Selections .........................................................................................................23 Field Methods .........................................................................................................26 Natural Variability and Measurement Error Analysis ............................................29 USGS Gage Calibration and Analysis ....................................................................29 Geospatial Methods ................................................................................................31 Channel Morphology Equations .............................................................................34 Chapter 4. Results and Discussion ....................................................................................35 Bankfull Discharge and Recurrence Intervals ........................................................35 Channel Morphology Equations .............................................................................39 Channel Substrate Characteristics ...........................................................................45 Stream Power Relationships ...................................................................................50 Variability of Channel Characteristics and Bedrock Influence ..............................53 Chapter 5. Conclusions ......................................................................................................56 References ..........................................................................................................................59 Appendices ........................................................................................................................68 Appendix A. Key to Appendices B and C ..............................................................68 Appendix B. Cross-Section Data ............................................................................69 Appendix C. Longitudinal Profile Data ................................................................150 Appendix D. Channel Substrate Data ...................................................................193 Appendix E. Photo Log.........................................................................................195 v LIST OF TABLES Table 1. Geologic units and descriptions within the James River basin ............................19 Table 2. Study site descriptions and coordinates ...............................................................25 Table 3. USGS gage records and roughness (n) values .....................................................31 Table 4. Historical changes in recurrence intervals for the James River ...........................38 vi LIST OF FIGURES Figure 1. General trends in the fluvial system .....................................................................2 Figure 2. Schematic of the bankfull channel .......................................................................5 Figure 3. Ozark Highlands physiographic region and sub-regions....................................10 Figure 4. Stable and disturbance reaches characteristic of Ozarks streams .......................13 Figure 5. James River basin in relation to the White River basin ......................................17 Figure 6.