NORTH FORK ST. LUCIE RIVER FLOODPLAIN VEGETATION TECHNICAL REPORT WR-2015-005 Coastal Ecosystem Section Applied Sciences Bureau Water Resources Division South Florida Water Management District Final Report July 2015 i Resources Division North Fork of the St. Lucie River Floodplain Vegetation Technical Report ACKNOWLEDGEMENTS This document is the result of a cooperative effort between the Coastal Ecosystems Section of South Florida Water Management District (SFWMD) and the Florida Department of Environmental Protection (FDEP), Florida Park Service (FPS) at the Savannas Preserve State Park in Jensen Beach, Florida and the Indian River Lagoon Aquatic Preserve Office in Fort Pierce, Florida. The principle author of this document was as follows: Marion Hedgepeth SFWMD The following staff contributed to the completion of this report: Cecilia Conrad SFWMD (retired) Jason Godin SFWMD Detong Sun SFWMD Yongshan Wan SFWMD We would like to acknowledge the contributions of Christine Lockhart of Habitat Specialist Inc. with regards to the pre-vegetation plant survey, reference collection established for this project, and for her assistance with plant identifications. We are especially grateful to Christopher Vandello of the Savannas Preserve State Park and Laura Herren and Brian Sharpe of the FDEP Indian River Lagoon Aquatic Preserves Office for their assistance in establishing the vegetation transects and conducting the field studies. And, we would like to recognize other field assistance from Mayra Ashton, Barbara Welch, and Caroline Hanes of SFWMD. Also, we would like to thank Kin Chuirazzi for performing a technical review of the document. ii North Fork of the St. Lucie River Floodplain Vegetation Technical Report TABLE OF CONTENTS Acknowledgements ..........................................................................................................................ii List of Tables ................................................................................................................................ vii List of Figures ................................................................................................................................. ix Acronyms and Abbreviations ........................................................................................................ xiii Introduction ................................................................................................................................. 1 Purpose and Scope.......................................................................................................................... 9 Previous Vegetation and Water Quality Studies ................................................................ 11 Topographical Characteristics and Geographical Information System Coverage .............. 14 Ecological Conceptual Model of Floodplain Vegetation ..................................................... 16 North Fork St. Lucie River Floodplain Taxonomic Plant Survey .......................................... 16 Methods ............................................................................................................................... 19 Air, Temperature and Rainfall ............................................................................................. 19 Soil Characteristics, Soil Electrical Conductivity and Soil Moisture Sampling .................... 19 River Flow and Salinity ........................................................................................................ 19 Vegetative Sampling ........................................................................................................... 20 Plant and Forest Type Identification ................................................................................... 24 Statistical Analysis ............................................................................................................... 24 Results ............................................................................................................................... 27 Air, Temperature and Rainfall ............................................................................................. 27 Soil Types, Soil Electrical Conductivity and Soil Moisture .................................................. 29 River Flow and Salinity ........................................................................................................ 33 Floodplain Vegetative Communities ................................................................................... 37 Forest Community Types .................................................................................................... 39 Transect Summaries ............................................................................................................ 40 Canopy Communities ...................................................................................................... 40 Canopy Abundance and Forest Type by Transect .......................................................... 43 The Structure of the Floodplain Canopy Community Using Multivariate Analysis ........ 55 Shrub and Groundcover Communities ........................................................................... 64 iii North Fork of the St. Lucie River Floodplain Vegetation Technical Report Shrub Community ........................................................................................................... 66 Groundcover Community ............................................................................................... 75 Discussion and Conclusions .......................................................................................................... 81 Floodplain Forest Impacts ................................................................................................... 85 Floodplain Restoration and Future Studies ........................................................................ 86 Impact of Climatic Events on Vegetative Changes ............................................................. 89 Literature Cited ............................................................................................................................. 93 Appendix A: 1944 and 1958 Black and White Aerials of the North Fork St. Lucie River and Location of Transect Benchmarks ....................................................................... 101 Appendix B: 1971 Plant List for the Freshwater Swamp of the North Fork St. Lucie River .... 109 Appendix C: 2009 North Fork St. Lucie River Plant Survey List ............................................... 113 Summary of Information in Table ..................................................................................... 126 Appendix D: Major Soils, Soil Electrical Conductivity and Soil Moisture on the North Fork St. Lucie River Floodplain ......................................................................................... 127 Appendix E: North Fork St. Lucie River Floodplain Soil Electrical Conductivity and Soil Moisture Data Set ............................................................................................... 133 Appendix F: Summary of Forest Type Determinations ........................................................... 137 Summary of Forest Type Determinations ......................................................................... 138 Uplands ......................................................................................................................... 140 Hammocks..................................................................................................................... 141 Riverine and Upper Tidal Reaches and High Bottomland Hardwoods ......................... 142 Riverine Swamps ........................................................................................................... 143 Upper Tidal Swamps ..................................................................................................... 144 Lower Tidal Forest ......................................................................................................... 145 Freshwater and Saltwater Marshes .............................................................................. 146 Appendix G: North Fork St. Lucie River Floodplain Data Sets and Additional Graphs ............ 147 Appendix H: Results and Additional Multi-Variate Analysis and Graphs ................................ 173 Results Canonical Correspondence Analysis Canopy Layer .............................................. 174 Scatterplot Matrix for Floodplain Canopy Abundance ..................................................... 176 Canopy Bray-Curtis (BC) Biplots ........................................................................................ 178 iv North Fork of the St. Lucie River Floodplain Vegetation Technical Report 2009 Shrub Percent Cover ................................................................................................ 194 Results Canonical Correspondence Analysis of Shrub Layer ............................................ 198 Shrub Species Bray Curtis (BC) Bi-plots............................................................................. 200 Appendix I: North Fork St. Lucie River Floodplain Grid Maps ................................................ 203 Floodplain LIDAR ............................................................................................................... 204 v North Fork of the St. Lucie River Floodplain Vegetation Technical Report vi North Fork of the St. Lucie River Floodplain Vegetation