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University of Florida Thesis Or Dissertation Formatting Template DISSOLVED OXYGEN DYNAMICS IN ISOLATED BLACKWATER WETLANDS By ROBERT F. COMPTON A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ENGINEERING UNIVERSITY OF FLORIDA 2014 © 2014 Robert Compton To my loving and supportive parents, Glenn and Mary Compton ACKNOWLEDGMENTS This study was funded through grant money from the United States Environmental Protection Agency and the Florida Department of Environmental Protection. I would like to thank my advisor and principal investigator, Dr. Mark Brown, and project manager Kelly Reiss. I would also like to acknowledge my committee members Dr. Treavor Boyer and Dr. Matthew Cohen. The FDEP staff provided support for this research, particularly Nijole Wellendorf, Ashley O’Neal, Joy Jackson, and Russ Frydenborg. Generous field assistance was provided by Sean Sharp, Jenet Dooley, Erica Hernandez, Fabio S, Valerie Burkett, and Lucia Zarba. 4 TABLE OF CONTENTS page ACKNOWLEDGMENTS .................................................................................................. 4 LIST OF TABLES ............................................................................................................ 7 LIST OF FIGURES .......................................................................................................... 9 LIST OF ABBREVIATIONS ........................................................................................... 10 ABSTRACT ................................................................................................................... 11 CHAPTER 1 INTRODUCTION .................................................................................................... 13 Introduction and Statement of Problem .................................................................. 13 Objectives and Plan of Study .................................................................................. 13 Regulatory Framework and Background................................................................. 15 Low DO in Blackwater Wetlands ............................................................................. 16 Drivers of Water Column DO in Wetlands ............................................................... 17 2 METHODS .............................................................................................................. 24 Site Selection .......................................................................................................... 24 Field Methods ......................................................................................................... 25 Data Analysis .......................................................................................................... 34 3 RESULTS AND DISCUSSION ............................................................................... 39 Dissolved Oxygen ................................................................................................... 39 Diel Oxygen Curves ................................................................................................ 40 Environmental Parameters ..................................................................................... 44 Vertical Dissolved Oxygen Profiles ......................................................................... 48 Discussion .............................................................................................................. 51 Conclusions ............................................................................................................ 61 APPENDIX A: INDIVIDUAL DIEL PLOTS BY WETLAND ............................................................... 74 B: PAIRWISE LINEAR CORRELATION TABLES ........................................................ 78 C: DIEL PLOTS AT MULTIPLE DEPTHS .................................................................... 81 D: GENERAL SITE INFORMATION FOR ALL WETLANDS ........................................ 83 5 E: MEASURED ENVIRONMENTAL PARAMETERS BY SITE .................................... 85 F: FIELD PHYSICAL/CHEMICAL SITE CHARACTERIZATION SHEET ...................... 90 LIST OF REFERENCES ............................................................................................... 91 BIOGRAPHICAL SKETCH ............................................................................................ 96 6 LIST OF TABLES Table page 2-1 Mean probe depths below water surface. ........................................................... 38 2-2 Wetland depth classification for 10 FD sites ....................................................... 38 2-3 Mean sonde deployment depths for “deep” and “shallow” wetlands ................... 38 3-1 DO summary statistics for wetland sites ............................................................. 70 3-2 Timing of DO maximums and minimums ............................................................ 70 3-3 Seasonal comparison of mean water quality parameters for ALHD1 ................. 70 3-4 Seasonal comparison of mean water quality parameters for ALFD1 .................. 70 3-5 Water quality by wetland type ............................................................................. 71 3-6 Mean daily range of pH and sp. conductance for FR, HR, and FD sites ............ 71 3-7 Soil parameters by depth class and wetland type ............................................... 71 3-8 Correlation of water quality and soil parameters for all wetlands ........................ 72 B-1 Correlation of water quality and soil parameters for FR sites.. ........................... 78 B-2 Correlation of water quality and soil parameters for HR sites ............................. 79 B-3 Correlation of water quality and soil parameters for FD sites ............................. 80 D-1 Site details for all wetlands ................................................................................. 83 E-1 Water quality data by site for FR wetlands ......................................................... 85 E-2 Water quality data by site for HR wetlands ......................................................... 86 E-3 Water quality data by site for FD wetlands. ........................................................ 86 E-4 Canopy cover, SAV presence, GPP, and R for FR wetlands ............................. 87 E-5 Canopy cover, SAV presence, GPP, and R for HR wetlands ............................. 87 E-6 Canopy cover, SAV presence, GPP, and R for FD wetlands ............................. 88 E-7 Soil data for FR wetlands by site. ....................................................................... 88 E-8 Soil data for HR wetlands by site. ....................................................................... 89 7 E-9 Soil data for FD wetlands by site. ....................................................................... 89 8 LIST OF FIGURES Figure page 1-1 Energy systems diagram of a blackwater swamp ............................................... 23 2-1 Locations of 41 wetland study sites .................................................................... 36 2-2 Field photograph of deployed sonde .................................................................. 36 2-3 Canopy cover photograph methodology ............................................................. 37 2-4 Atmospheric diffusion rates at different depths ................................................... 37 3-1 Diel DO plots for a forested and heraceous wetland .......................................... 63 3-2 Mean nighttime and daytime DO of selected wetlands ....................................... 63 3-3 Diel DO plots for DIFB1 and SAHD1. ................................................................. 64 3-4 Comparison of morning grab samples with continuous measurements .............. 64 3-5 Examples of observed wetland nighttime DO spikes .......................................... 65 3-6 Diel DO, water temperature, and air temperature plot ........................................ 65 3-7 Diel DO and temperature plot measured at SAHD2 ........................................... 66 3-8 Seasonal comparison of diel DO plots for ALHD1 and ALFD1 ........................... 66 3-9 Diel DO and pH plots recorded at LEFD1 and SAHD1 ....................................... 67 3-10 PCA ordination ................................................................................................... 67 3-11 Diel DO time series for a deep and shallow wetland .......................................... 68 3-12 Mean daily DO saturation for individual wetlands at multiple depths .................. 68 3-13 Comparison of DOm to DOwc in three wetlands ................................................... 69 9 LIST OF ABBREVIATIONS ANOVA Analysis of Variance Chl-a Chlorophyll-a DO Dissolved Oxygen DOC Dissolved Organic Carbon FD Forested – Disturbed FR Forested – Reference GPP Gross Primary Production HR Herbaceous – Reference LDI Landscape Development Intensity PCA Principal Component Analysis RI Recalcitrance Index R Respiration Soil %OM Percent Soil Organic Matter SOP Standard Operating Procedure SSAC Site Specific Alternative Criteria TKN Total Kjeldahl Nitrogen TN Total Nitrogen TOC Total Organic Carbon TP Total Phosphorus YSI Yellow Springs Instruments 10 Abstract of Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Engineering DISSOLVED OXYGEN DYNAMICS IN ISOLATED BLACKWATER WETLANDS By Robert Compton August 2014 Chair: Mark Brown Major:
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