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The Hydrology and Sediment Transport of Low-Gradient, Forested Headwater Streams

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The Hydrology and Sediment Transport of Low-Gradient, Forested Headwater Streams Louisiana State University LSU Digital Commons LSU Master's Theses Graduate School 2007 The yH drology and Sediment Transport of Low- Gradient, Forested Headwater Streams Philip Saksa Louisiana State University and Agricultural and Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_theses Part of the Environmental Sciences Commons Recommended Citation Saksa, Philip, "The yH drology and Sediment Transport of Low-Gradient, Forested Headwater Streams" (2007). LSU Master's Theses. 160. https://digitalcommons.lsu.edu/gradschool_theses/160 This Thesis is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Master's Theses by an authorized graduate school editor of LSU Digital Commons. For more information, please contact [email protected]. THE HYDROLOGY AND SEDIMENT TRANSPORT OF LOW-GRADIENT, FORESTED HEADWATER STREAMS A Thesis Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Master of Science in The School of Renewable Natural Resources by Philip Saksa B.S., The Ohio State University, 2003 December 2007 ACKNOWLEDGMENTS Many thanks are owed to the numerous people who helped make this accomplishment possible. Much appreciation goes to my major advisor, Dr. Jun Xu, for providing this opportunity, and his constant drive and energy devoted towards this project. I would also like to thank my committee members Dr. Jim Chambers and Dr. Dan Thomas, for the insightful discussions and ideas they brought to this work. My lab mates, April Mason and Adrienne Viosca, whose collaboration, hard work, and friendship are invaluable. Finally, the support and encouragement I received from my family and friends, most especially my parents, will always be remembered - thank you so much. ii TABLE OF CONTENTS ACKNOWLEDGMENTS .............................................................................................................. ii LIST OF TABLES.......................................................................................................................... v LIST OF FIGURES ...................................................................................................................... vii ABSTRACT................................................................................................................................... xi CHAPTER 1. INTRODUCTION ................................................................................................... 1 CHAPTER 2. LITERATURE REVIEW………………………………………………………….6 2.1 Hydrology of Headwater Streams......................................................................................... 6 2.2 Sediment Transport in Headwater Streams......................................................................... 10 2.2.1 Suspended Sediments................................................................................................... 11 2.2.2 Dissolved Solids........................................................................................................... 13 2.3 Ponding in Forested Headwater Streams ............................................................................ 15 2.3.1 Debris Dams................................................................................................................. 15 2.3.2 Beaver Dams................................................................................................................ 17 2.4 Hydrologic Simulation........................................................................................................ 19 2.4.1 Spatial Modeling.......................................................................................................... 19 2.4.3 Soil and Water Assessment Tool (SWAT) .................................................................. 20 CHAPTER 3. METHODS............................................................................................................ 23 3.1 Site Description................................................................................................................... 23 3.2 Streamflow Measurements, Water Sampling and Weather Observation............................ 27 3.3 Development of Stage-Discharge and Sediment Rating Curves ........................................ 32 3.4 Hydrologic Modeling.......................................................................................................... 34 CHAPTER 4. RESULTS.............................................................................................................. 37 4.1 Hydrology ........................................................................................................................... 37 4.1.1 Seasonal Conditions..................................................................................................... 37 4.1.2 Stormflow Hydrology .................................................................................................. 43 4.2 Suspended Solids ................................................................................................................ 50 4.2.1 Baseflow Total Suspended Solids (TSS) ..................................................................... 50 4.2.2 Stormflow TSS ............................................................................................................ 55 4.3 Dissolved Solids.................................................................................................................. 58 4.3.1 Baseflow Total Dissolved Solids (TDS)...................................................................... 58 4.3.2 Storm TDS ................................................................................................................... 63 4.4 Hydrologic Modeling.......................................................................................................... 66 4.4.1 Streamflow Initial Simulation and Calibration............................................................ 66 4.4.2 Simulation Accuracy.................................................................................................... 71 CHAPTER 5. DISCUSSION........................................................................................................ 75 iii 5.1 Hydrologic Responses in the Flat Creek Headwaters......................................................... 75 5.2 Sediment Transport in the Flat Creek Headwaters ............................................................. 78 5.3 Applicability of the SWAT Model ..................................................................................... 86 CHAPTER 6. CONCLUSIONS ................................................................................................... 91 REFERENCES ............................................................................................................................. 93 VITA........................................................................................................................................... 104 iv LIST OF TABLES 3.1. Descriptions of stream monitoring locations (sites) where stream discharge was measured, and water samples were collected......................................................................................... 28 3.2. Discharge, Total Suspended Solid (TSS) and Total Dissolved Solid (TDS) r-squares from log-linear regression. Discharge (m3/s) is related to stream depth (m) where TSS loading (kg) & TDS loading (kg) is related to discharge................................................................... 34 3.3. Parameters adjusted in the Soil and Water Assessment Tool (SWAT) during model calibration. Ranges are recommended, and default values given are from the initial model run, before calibration........................................................................................................... 36 4.1. Amount of precipitation converted into runoff with wet and dry antecedent conditions, in order of increasing drainage area. Use of one weather station to measure precipitation assumes uniform precipitation, and may result in errors from unknown spatial variation... 41 4.2. Descriptive statistics of daily streamflow (L/s) for all sample sites. .................................... 43 4.3. Dates of sampled storms with “x” denoting a storm sample at the respective site. Missing storm samples were due to variation in individual site response, equipment malfunctions, or laboratory testing problems................................................................................................... 44 4.4. Storm hydrograph characteristics for all intensive sites in response to a 34.0 mm precipitation event, occurring on 02 Feb 2006. .................................................................... 45 4.5. Stormflow recession constants for sites with increasing drainage areas. Coefficients of determination (r2) are calculated between predicted recessions using the individual equation, and observed streamflow recessions..................................................................................... 48 4.6. Stream Total Suspended Solid (TSS) concentrations determined from monthly baseflow water sampling over the study period. Dashed (-) values represent no flow during monthly sampling................................................................................................................................ 51 4.7. Log transformed regression coefficients of determination between Precipitation
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