Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1995 Increased Salinity and Water Depth as Constraints on Growth of Freshwater Marsh Plants. Rebecca J. Howard Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Howard, Rebecca J., "Increased Salinity and Water Depth as Constraints on Growth of Freshwater Marsh Plants." (1995). LSU Historical Dissertations and Theses. 6107. https://digitalcommons.lsu.edu/gradschool_disstheses/6107 This Dissertation 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 Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back of the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6” x 9” black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. UMI A Bell & Howell Information Company 300 North Zed) Road, Ann Arbor MI 48106-1346 USA 313/761-4700 800/521-0600 INCREASED SALINITY AND WATER DEPTH AS CONSTRAINTS ON GROWTH OF FRESHWATER MARSH PLANTS A Dissertation 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 Doctor of Philosophy in The Department of Oceanography and Coastal Sciences by Rebecca J . Howard B.S., State University of New York College of Environmental Science and Forestry, 1976 M.S., University of Massachusetts, 1982 December 1995 UMI Number: 9618297 UMI Microform 9618297 Copyright 1996, by UMI Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. UMI 300 North Zeeb Road Ann Arbor, MI 48103 ACKNOWLEDGMENTS Many individuals have assisted in completion of the research described herein. I want to first express my gratitude to .the chairman of my committee, Dr. Irving Mendelssohn, for his invaluable guidance throughout this project. The other members of my committee, Dr s. James Grace, John Day, Jr., Robert Gambrell, and Janet Keough, also provided much-appreciated advice on research direction and constructively reviewed various manuscripts. Accurate field and greenhouse data collection and sample processing during this project would not have been possible without the assistance of several individuals. I especially want to thank John McCoy, Wayne Norling, and Libby Loggerwell for their help under often unpleasant conditions. The statistical advice and review provided by Debbie Fuller and Darron Johnson is very much appreciated. This research would not have been possible without the support of many of my colleagues in the National Biological Service (formerly U.S. Fish and Wildlife Service). Special thanks are extended to Drs. Ed Pendleton and Larry Ludke for encouraging me to pursue, and Dr. Robert Stewart for supporting me throughout, this effort. All financial and logistical support was provided by the Southern Science Center, National Biological Service. I also want to acknowledge the cooperation of the National Park Service, ii Jean Lafitte National Historical Park and Preserve, in allowing access to the Barataria Preserve Unit to conduct field work. iii TABLE OT CONTENTS ACKNOWLEDGEMENTS..................................... i i LIST OF TABLES....................................... V LIST OF FIGURES...................................... vii ABSTRACT............................................. xi CHAPTER 1. INTRODUCTION AND LITERATURE REVIEW....... 1 CHAPTER 2. EFFECT OF INCREASED WATER DEPTH ON GROWTH OF A COMMON PERENNIAL FRESHWATER- INTERMEDIATE MARSH SPECIES IN COASTAL LOUISIANA................................ 11 CHAPTER 3. SALINITY PULSES AS CONSTRAINTS ON GROWTH OF COMMON OLIGOHALINE MARSH PLANTS OF THE NORTHERN GULF OF MEXICO. I. SPECIES VARIATION IN STRESS TOLERANCE........... 43 CHAPTER 4. SALINITY PULSES AS CONSTRAINTS ON GROWTH OF COMMON OLIGOHALINE MARSH PLANTS OF THE NORTHERN GULF OF MEXICO. II. ABILITY TO RECOVER IN FRESHWATER CONDITIONS........ 76 CHAPTER 5. SALINITY PULSE EFFECTS ON OLIGOHALINE MARSH PLANT COMMUNITY STRUCTURE AND COMPOSITION.............................. 115 CHAPTER 6. SUMMARY AND CONCLUSIONS................... 162 LITERATURE CITED..................................... 167 APPENDIX LETTER OF PERMISSION....................... 178 VITA.................................................. 180 iv LIST or TABLES 2.1 Plant response variables by water treatment.. 23 2.2 Nutrient concentration in leaf tissue........ 24 2.3 Elemental analyses of soil interstitial water (ppm) and soil-water pH, salinity (ppt), and conductivity (micromhos/cm x 104 at 25° C).... 29 3.1 Description of experimental treatments....... 49 3.2 A priori linear contrasts used in analysis of variance............................ 52 3.3 Analysis of variance of final salinity effect on plant growth ...................... 54 3.4 Analysis of variance of salinity influx rate effect on plant growth...................... 59 3.5 Plant growth response measures in salinity treatments (influx rates combined) expressed as percent of corresponding control treatment value at 3 durations of exposure............ 63 3.6 Analysis of variance with repeated measures of plant growth responses to experimental treatments over 3 months.................... 64 4.1 A priori linear contrasts used in analysis of variance..................................... 83 4.2 Aboveground tissue mortality by treatment.... 85 4.3 Analysis of variance of plant growth response to salinity pulses of various durations 86 4.4 Analysis of variance of plant tissue nutrient response to salinity pulses of various durations.................................... 92 4.5 Analysis of variance with repeated measures of plant growth response to experimental treatments over 1, 2, and 3 months.......... 100 5.1 Soil texture and organic matter (%, mean ± l SE, n«3) at collection sites for two emergent plant communities............................ 126 v 5.2 Univariate 3-way analysis of variance results for the effect of salinity pulses on aesocosm chemical characteristics at time of harvest.. 129 5.3 Community 1 univariate 3-way analysis of variance results for the effect of salinity pulses on plant growth...................... 135 5.4 community 2 univariate 3-way analysis of variance results for the effect of salinity pulses on plant growth...................... 138 5.5 Macrophyte species identified in aesocosms... 148 vi LIST OF FIGURES 2.1 Location of the Barataria Unit of Jean Lafitte National Historical Park and Preserve and experimental design...................... 15 2.2 Mean (a) and maximum (b) leaf heights over time for the 1989 and 1990 growing seasons... 26 2.3 Water depth above marsh surface at six locations along Pipeline Canal from July 1989 to July 1990................................. 27 2.4 Post-treatment mean interstitial water sulfide and ammonium-N concentrations....... 30 2.5 Post-treatment mean oxidation-reduction potential at 2- and 15-cm depths............ 31 2.6 Eh measurements over time obtained at depths of 2 cm (a) and 15 cm (b)................... 32 2.7 Interstitial water sulfide concentration over time......................................... 33 3.1 Simplified experimental design indicating one of three blocks.............................. 50 3.2 Aboveground live biomass at harvest for control (treatment 1), 6 g/L (treatments 2 and 3), and 12 g/L (treatments 4 and 5), in Eleocharls palustris, Paulcum hemitomon, Sagittaria l a n d folia, and Sclrpus americanus................................... 55 3.3 Mean stem height at harvest for control (treatment 1), 6 g/L (treatments 2 and 3)r and 12 g/L (treatments 4 and 5), in Eleocharls palustris, Panicum hemitomon, Sagittaria landfolia, and Sclrpus americanus................................... 57 3.4 Aboveground live biomass at harvest by treatment and duration of exposure in Eleocharls palustris, Panicum hemitomon, Sagittaria landfolia, and Sclrpus americanus................................... 61 3.5 Total biomass at harvest by treatment and duration of exposure in Eleocharis palustris, vii Panicum hemitomon, Sagittaria landfolia,