University of New Hampshire University of New Hampshire Scholars' Repository Master's Theses and Capstones Student Scholarship Spring 2012 Ecosystem structure and function in an urban, piped stream Amanda Hope University of New Hampshire, Durham Follow this and additional works at: https://scholars.unh.edu/thesis Recommended Citation Hope, Amanda, "Ecosystem structure and function in an urban, piped stream" (2012). Master's Theses and Capstones. 701. https://scholars.unh.edu/thesis/701 This Thesis is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Master's Theses and Capstones by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. ECOSYSTEM STRUCTURE AND FUNCTION IN AN URBAN, PIPED STREAM BY AMANDA HOPE B.S., Eastern Nazarene College, 2002 THESIS Submitted to the University of New Hampshire in Partial Fulfillment of the Requirements for the Degree of Master of Science in Natural Resources May, 2012 UMI Number: 1518004 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. UMI 1518004 Published by ProQuest LLC 2012. Copyright in the Dissertation held by the Author. Microform Edition © ProQuest LLC. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 This thesis has been examined and approved. Thesis Director, Dr. William H. McDowell, Professor of Environmental Sciences Dr. Wilfred Wollheim, Assistant Professor of Environmental Sciences and Earth, Oceans, and Space A4-J1 Dr. Gretchen Gettel, Lecturer in Aquatic Biogeochemistry, UNESCO-IHE Institute for Water Education M(5|qo|3- Date ACKNOWLEDGEMENTS I would like to thank my committee: Bill McDowell, Wil Wollheim, and Gretchen Gettel. I appreciate their encouragement and the time they spent with me, providing research guidance and insight into the world of academic science. The opportunity to work with these outstanding individuals was a valued privilege. I am very grateful to Jody Potter, Jeff Merriam, Adam Baumann, and Michelle Daley from the NH Water Resources Research Center lab. This research could not have been completed without the many hours they devoted to assisting me with equipment, sample analyses, and problem-solving. Thank you to all the other fellow students and colleagues who offered moral support and helpful suggestions. I'd also like to thank Tom Dubois and Ruth Abelmann, as well as my friends, family, and God who sustained me throughout this process. My husband, James, never failed to believe in me with patient, unconditional love. This research was funded by the NH Water Resources Research Center. Additional graduate support was provided by the UNH Department of Natural Resources and the Environment, as well as the Plum Island Ecosystem Long Term Ecological Research Program (NSF LTER OCE- 0423565). iii TABLE OF CONTENTS SECTION PAGE ACKNOWLEDGEMENTS iii LIST OF TABLES vii LIST OF FIGURES viii ABSTRACT ix CHAPTER I: INTRODUCTION 1 Urban Threats to Stream Ecosystems 1 Prevalence of Buried and Piped Streams 2 Ecological Studies Regarding Piped Streams 3 Importance of Ecosystem Processes 4 Ecosystem Metabolism 5 Nutrient Spiraling 7 Summary of Research Needs 11 Project Overview 13 CHAPTER II: METHODS 17 Study Site 17 Stream Characterization 21 Water Chemistry Analyses 23 iv Ecosystem Metabolism 24 Ecosystem Metabolism Calculations 27 Nutrient Uptake 31 Nutrient Uptake Calculations 33 Chlorophyll a and Ash Free Dry Mass of Epilithon & Benthic Organic Matter...35 Chlorophyll a and Ash Free Dry Mass Calculations 37 Statistical Analyses 39 CHAPTER III: RESULTS 40 Chemical and Physical Parameters 40 Reaeration 46 Ecosystem Metabolism 47 Benthic Ash Free Dry Mass and Pigment Biomass 50 Dissolved Organic Carbon (DOC) Uptake 53 Nitrate (NO3) Uptake 54 Ammonium (NH4) Uptake 55 Phosphate (PO4) Uptake 58 Entire Reach Nutrient Uptake Values 58 CHAPTER IV: DISCUSSION 61 Chemical and Physical Parameters 61 Reaeration 63 v Ecosystem Metabolism 64 Benthic Ash Free Dry Mass and Pigment Biomass 67 Nutrient Uptake 69 Strengths and Limitations of Study Results 75 Implications of the Results at the Stream and Landscape Scale 75 Ecological and Management Implications of the Results 77 CHAPTER V: CONCLUSION 81 REFERENCES 83 APPENDICES 94 APPENDIX A: LITERATURE REVIEW 95 APPENDIX B: BACKGROUND SAMPLING WATER CHEMISTRY DATA 107 APPENDIX C: SPRING EXPERIMENT WATER CHEMSITRY DATA 113 APPENDIX D: SUMMER EXPERIMENT WATER CHEMISTRY DATA 119 APPENDIX E: EXAMPLE ECOSYSTEM METABOLISM 02 GRAPHS 140 APPENDIX F: ECOSYSTEM METABOLISM VALUES 142 APPENDIX G: BENTHIC AFDM AND PIGMENT BIOMASS VALUES 143 APPENDIX H: EXAMPLE NUTRIENT UPTAKE GRAPHS 144 APPENDIX I: NUTRIENT UPTAKE VALUES 147 vi LIST OF TABLES TABLE PAGE Table 1. GPS coordinates for study reaches in Pettee Brook 21 Table 2. Stream chemistry during assessments of nutrient uptake and ecosystem metabolism 43 Table 3. Stream characteristics during assessments of nutrient uptake and ecosystem metabolism 44 Table 4. Ecosystem metabolism changes in piped reaches of Pettee Brook 67 Table 5. Observed anthropogenic impacts to Pettee Brook, 2009-2010 79 vii LIST OF FIGURES FIGURE PAGE Figure 1. Diagram of study reaches 20 Figure 2. Average ambient solute concentrations 40 Figure 3. Ambient nutrient concentrations 41 Figure 4. Daily PAR 42 Figure 5. Relationship between Reaeration rates derived from SF6 additions and equations 3,4,6,7 found in Raymond et al. (in press) 46 Figure 6. Standardized reaeration rates 47 Figure 7. Average GPP 48 Figure 8. Average ER 49 Figure 9. Average NEP 49 Figure 10. Average P/R ratios 50 Figure 11. Ash free dry mass of surface FBOM and epilithon 51 Figure 12. Chlorophyll a and pheophytin biomass of surface FBOM and epilithon 52 Figure 13. DOC uptake 54 Figure 14. Summer NH4 uptake 55 Figure 15. Spring NH4 uptake 56 Figure 16. Background corrected NH4-N and NOrN flux for Pipe 1, 8/18/2009 57 Figure 17. Nutrient uptake velocity in Reaches 1 and 2 of Pettee Brook 59 Figure 18. Areal uptake in Reaches 1 and 2 of Pettee Brook 59 viii ABSTRACT ECOSYSTEM STRUCTURE AND FUNCTION IN AN URBAN, PIPED STREAM by Amanda Hope University of New Hampshire, May, 2012 Piped streams, or streams that run underground, are common features in urban areas. However, there is little empirical evidence regarding their ecological structure and function. This study measured ecosystem metabolism, nutrient uptake, and related characteristics of Pettee Brook - an urban stream that flows through several pipes under impervious surfaces near the UNH (Durham) campus. Piped and open reaches of Pettee Brook had similar water quality, nutrient uptake, and ER. However, the absence of light in piped reaches led to their complete loss of GPP. Benthic AFDM and chlorophyll a biomass were also significantly reduced in piped reaches. For both open and piped reaches, spring metabolism and nutrient uptake were elevated compared to summer rates. The results suggest that ecological conditions in piped streams may be degraded beyond the extent of other urban stream reaches. However, piped stream reaches may still offer some ecosystem services such as nutrient uptake during ER. ix CHAPTER I - INTRODUCTION Urban Threats to Stream Ecosystems Urban impairment of aquatic ecosystems (reviewed by Paul and Meyer 2001, Walsh et al. 2005b) threatens the quality and diversity of life on Earth, including human health and well being (Palmer et al. 2004). Degraded urban streams fail to adequately support water uses such as drinking, sanitation, industry, flood protection, agriculture, fisheries, and recreation. There is an urgent need to find ecological solutions to this problem (Grimm et al. 2008). Urban stream impairment is associated with development that covers watersheds with impervious surfaces, such as pavement and buildings. The impervious surfaces are connected to streams by efficient drainage systems (e.g. gutters and storm drains, Walsh et al. 2005a). This land use reduces infiltration and increases storm water flow into streams, resulting in streams that suffer from altered channel geomorphology, elevated concentrations of nutrients and contaminants, and reduced biodiversity. Stream ecological processes, such as organic matter retention, nutrient uptake, and ecosystem metabolism, may also be affected (Paul and Meyer 2001, Walsh et al. 2005b, Grimm et al. 2005, Meyer et al. 2005). In addition to the problems caused by impervious surfaces and efficient drainage systems, urban streams are also directly impaired by channelization and burial (Elmore 1 and Kaushal 2008). Channelization involves straightening urban streams and/or lining stream beds with hard materials such as concrete. Burial occurs when urban streams are completely filled with material, as well as when streams are diverted through underground pipes (referred to as "stream piping" and "piped streams"). These practices create urban streams that may be extremely degraded; losses include aquatic habitat, sediment and nutrient retention, and primary productivity (Elmore and Kaushal 2008, Doyle and Bernhardt 2011). Prevalence of Buried and Piped Streams Buried streams (filled-in streams as well as piped streams) are prevalent in urban watersheds. Elmore and Kaushal (2008) found that buried streams comprised 20% to 70% of all streams in the region surrounding Baltimore, MD (with the highest percentage in Baltimore City). Roy et al. (2009) estimated that 93% of ephemeral and 46% of intermittent stream length was buried in the region near Cincinnati, OH. Stream piping was widespread in perennial streams, with 40% of perennial streams originating from pipes. Twenty-eight percent of piped streams had continuous flow (Roy et al. 2009). Piped streams are also common in New England.