DOCSLIB.ORG

Nitrogen Cycling and Assimilative Capacity of Nitrogen and Phosphorus by Riverine Wetland Forests

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Nitrogen Cycling and Assimilative Capacity of Nitrogen and Phosphorus by Riverine Wetland Forests Nitrogen Cycling and Assimilative Capacity of Nitrogen and Phosphorus by Riverine Wetland Forests by Mark M. Brinson H. David Bradshaw Emilie S. Kane Department of Bi 01 ogy East Carolina University Greenvi 1 le, North Carol ina 27834 The work upon which this publication is based was supported in part by funds provided by the Office of Water Research and Technology, U.S. Department of the Interior, Washington, D.C., through the Water Resources Research Institute of the University of North Carolina as authorized by the Water Research and Development Act of 1978. Project No. B-114-NC Agreement No. 14-34-0001 -81 07 May 1981 This work was made possible with the assistance and support from a number of people. Martha Jones maintained structure and function in the laboratory environment and performed many of the nutrient analyses. Jerry Freeman contributed greatly to equipment supply and repair. Richard Volk of North Carolina State University kindly made available his mass spectro- meter for our use. Assistance in field work was provided by Randy Creech, Debbie Noltemeier, and Steve Nelson. Most of the figures were drafted by Nancy Edwards of the Regional Development Institute of East Carol ina University. We appreciate the sharing of ideas and have benefited greatly from discussions with Edward J. Kuenzler, Laura A. Yarbro, Patrick J. Mulholland, and Robert P. Sniffen, fellow enthusiasts of North Carolina swamps. Graham J. Davis read an earlier draft of the report and offered helpful comments. We appreciate the efforts of Arlene Hagar who typed the final draft. DISCLAIMER STATEMENT Contents of this publication do not necessarily reflect the views and policies of the Office of Water Research and Technology, U.S. Depart- ment of the Interior, nor does mention of trade names or commercial products constitute their endorsement or recommendation for use by the U.S. Government. ABSTRACT In riverine swamps, opportunities for nutrient exchange between surface water and the sediments of the swamp forest floor occur when streams flood and water overflows into the swamps and when runoff from uplands passes through floodplains. Studies conducted in floodplain swamps of two repre- sentative types in eastern North Carol ina provided insight into these processes. Nitrogen cycling experiments were conducted in both ecosystems with one system being subjected to sustained nutrient loading to assess its assimilative capacity. Labeled (15~)nitrate and ammonium were added to swamp surface water and their diffusion to the forest floor was followed. Of the original nitrate added, 46% remained in the surface water of Tar Swamp and 62% in Creeping Swamp after 2 days. Two days after ammonium treatments, correqeonding levels were 79% and 81%. As indicated by the absence of recoverable N in sediments following nitrate treatments, diffusion of labeled nitrate to the forest floor resulted in its transformation to N2O or N2 by denitrification. Although labeled ammonium also diffused to sediments and accumulated in a sediment-exchangeable form, there was simultaneous efflux of unlabeled ammonium from sediments to the water column. Also, ammonium was readily immobilized from the water by decomposing leaf litter and probably fila- mentous algae, both of which represent short term storages. However, exchangeable ammonium in the sediments was far more important in net accumulation. During the drydown phase, which is an annual summer-fall event in tupelo- cypress swamps, surficial sediment became aerated. Analysis of interstitial water indicated that this stimulated production of ammonium from organic nitrogen (ammonification) and subsequent nitrate production from ammoni um (nitrification). After short term pu1 ses of accumulation of these forms, nitrate was denitrified. Thus, available nitrogen reserves in the sediments were depleted during annual drydown episodes, and the capacity for additional nitrogen assimilation by the sediments was renewed. An experiment was then conducted to determine the capacity of sediments for sustained nutrient assimilation by adding nitrate, ammonium, phosphate, and secondarily treated sewage effluent to surface water in separate chambers at weekly intervals for 46 weeks. Nitrate disappeared rapidly from the surface water between weekly additions and did not accumulate in subsurface water; denitrification was estimated to proceed at a minimal rate of 24.5 g NQ~-N.~-~over the 10-month loading period. Substantial quantities of ammonium accumulated in surface water, and after a lag period, in the exchangeable ammonium fraction of sediment. However, summer drydown depleted these accumulations, presumably by the ni rification-deni trification pathway, for an overall ammonium loss of 13.5 g-m-B-10mo-1 in ammonium treatments. Phosphate added to surface water accumulated as an acid-extractable form in sediments to a level of nearly one-half of total sediment phosphorus by the end of the experiment. Although rates of phosphate addition in these treatments were severalfold higher than the treatment receiving sewage effluent, the inherently phosphate-rich sediments and the lack of an atmos- pheric escape pathway for phosphorus may limit the capacity of the swamp for further phosphate assimilation and 1ong-term sewage appl ication. ABSTRACT (Continued) Studies on the distribution of biomass and nutrients in lateral roots were conducted in the two riverine swamps. Lateral root biomass (2345-2702 g dry wtom-2) and nutrient stocks (for N, P, Ky Ca, Mgy Na) fell within the range for other forested wetlands and uplands. However, Fe concentrations in roots and stocks of Fe per unit area of swamp floor may be severalfold higher than in upland forests, presumably because of greater Fe mobility in wetland sediments and Fe precipitation on root surfaces. In the tupelo swamp, a trend of increasing root biomass with increasing depth is a pattern hitherto unreported for forested ecosystems. TABLE OF CONTENTS Page ACKNOWLEDGMENTS ......................; .. i i ABSTRACT ............................. iii LIST OF FIGURES ......................... vii LISTOFTABLES .......................... ix CONCLUSIONS AND RECOMMENDATIONS ................. xi 1 . INTRODUCTION Contents and Purpose ................... 1 Southeastern River Swamps: Distribution. Structure andFunction ...................... 1 Nutrient Cycling in Swamp Forests ............. 4 Description of Study Area ................. 9 Tar Swamp ....................... 9 Creeping Swamp ..................... 10 2 . WATER-SEDIMENT NITROGEN TRANSFORMATIONS Introduction ....................... 13 Methods .......................... 13 15~Enrichment Experiments ............... 13 Field Work and Sample Collection .......... 13 Methods of Sample Analysis ............. 14 Moisture ..................... 14 Total Kjeldahl Nitrogen ............. 14 15~Analysis ................... 15 Exchangeable NH4 and NO3 ............. 16 Leaves and Woody Matter ............. 16 Surface Water .................. 16 Ammonia Volatilization ................. 16 Ammonium and Nitrate in Interstitial Water ....... 17 Results .......................... 17 15~Experiments .................... 17 Temperature and Dissolved Oxygen .......... 17 Distribution of 15~................. 17 Seasonal Nitrogen Transformations in Interstitial Water ..................... .. 20 Ammonia Volatilization ................. 24 Discussion ........................ 25 3 . SUSTAINED LOADING OF NITROGEN AND PHOSPHORUS TO THE SEDIMENT-WATER SYSTEM Introduction ....................... 27 LIST FIGURES Page 1. Idealized profile of species associations in southeastern bottomland hardwood forests. ................. 3 2. Seasonal changes in the physical and chemical environment of Tar Swamp ......................... 11 3. Losses of inorganic nitrogen and changes in atom % 15~of the surface water of (a) Tar Swamp and (b) Creeping Swamp .... 20 4. Accumulation of 15~in decomposing leaf detritus of Tar Swamp and Creeping Swamp expressed as (a) mg 15~akg leaf-] and (b) ratio of concentration in leaves at the end of the experiment and water at the beginning of theexperiment ........................21 5. Amount of 15~recovered from chambers in Tar Swam after 5 days and Creeping Swamp after 7 days since 18NH4 or 15~0~addition to surface water ............... 22 6. Changes in inorganic nitrogen pools in the interstitial water of surficial sediment of Tar Swamp as related to percentage cover of water in sampling area ............... 23 7. Design of nutrient loading experiment .............. 30 8. Precipitation (a) and water level (b) at Tar Swamp from February 1979 through February 1980 ............. 36 9. Ammonium concentrations of surface water (a) in the NH4 and PNN treatments, (b) in the sewage treatment, and (c) in controls not receiving ammonium loading ........ 40 10. Ammonium concentrations of subsurface water in (a) NHq, PNN, and sewage treatments, (b) PO4 and NO3 treatments, and (c) controls .......................41 11. Exchangeable ammonium concentrations of the surface sediment for (a) NHq, PNN, and sewage treatments, and (b) NO3 and PO4 treatments and controls ............... 42 12. Nitrate concentrations of surface water in the (a) NO3 and PNN treatments and (b) sewage treatment ........... 43 13. Fi l terable reactive phosphorus (FRP) concentrati ons of surface water in (a) PO4 and PNN treatments, (b) sewage treatment, and (c).controls not receiving phosphate loading ....... 44 LIST OF FIGURES (Continued) Page 14. Fi l terabl e reactive phosphorus (FRP) concentrations
Load more

Recommended publications
  • Streamflow Decline in the Yellow River Along with Socioeconomic
    water Article Streamflow Decline in the Yellow River along with Socioeconomic Development: Past and Future Shi Lun Yang 1,*, Benwei Shi 1 , Jiqing Fan 1, Xiangxin Luo 2, Qing Tian 3, Haifei Yang 4, Shenliang Chen 1 , Yingxin Zhang 1, Saisai Zhang 5, Xuefa Shi 6 and Houjie Wang 7,8 1 State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China; [email protected] (B.S.); [email protected] (J.F.); [email protected] (S.C.); [email protected] (Y.Z.) 2 Institute of Estuarine and Coastal Research, Sun Yat-sen University, Guangzhou 510275, China; [email protected] 3 School of Marine Science, Nanjing University of Information Science and Technology, Nanjing 210044, China; [email protected] 4 Survey Bureau of Hydrology and Water Resources of the Changjiang Estuary, Bureau of Hydrology, Changjiang Water Resources Commission, Shanghai 200136, China; [email protected] 5 Shanghai Waterway Engineering Design and consulting Co., Ltd., Shanghai 200120, China; [email protected] 6 Key Laboratory of Marine Sedimentology & Environmental Geology, First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China; xfshi@fio.org.cn 7 Key Laboratory of Submarine Geosciences and Prospecting Techniques, College of Marine Geosciences, Ocean University of China, 238 Songling Rd., Qingdao 266100, China; [email protected] 8 Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266061, China * Correspondence: [email protected] Received: 28 January 2020; Accepted: 6 March 2020; Published: 14 March 2020 Abstract: Human society and ecosystems worldwide are increasinAagly threatened by water shortages.
    [Show full text]
  • Proposed Waters of the United States Rulemaking (EPA-HQ-2017-0203)
    September 27, 2017 Via www.regulations.gov The Honorable Scott Pruitt Administrator U.S. Environmental Protection Agency Office of the Administrator Mail Code 1101A 1200 Pennsylvania Avenue, N.W. Washington, DC 20460 The Honorable Douglas W. Lamont Deputy Assistant Secretary of the Army Office of the Assistant Secretary of the Army for Civil Works Department of the Army 108 Army Pentagon Washington, DC 20310 Re: Proposed waters of the United States rulemaking (EPA-HQ-2017-0203) Dear Administrator Pruitt and Deputy Secretary Lamont: The Southern Environmental Law Center submits the following comments on behalf of itself and 63 organizations that share a common commitment to clean water and healthy wetlands. These organizations and their millions of members recognize that clear, predictable protections for streams and wetlands—as provided by the Clean Water Rule—are essential to safeguarding the waters where Americans swim, fish, boat, paddle, hunt, and get their drinking water. This rulemaking would eliminate these protections without justification. We respectfully request that the U.S. Environmental Protection Agency and the U.S. Army Corps of Engineers withdraw the proposed rule. The Southern Environmental Law Center submits these comments on behalf of: Alabama Rivers Alliance, Altamaha Riverkeeper, Appalachian Voices, Atlanta Audubon Society, Black Warrior Riverkeeper, Blue Ridge Land Conservancy, Broad River Alliance, Cahaba River Society, Carolina Wetlands Association, Catawba Riverkeeper Foundation, Center for a Sustainable Coast,
    [Show full text]
  • Prohibit State Agencies from Regulating Waters More Stringently Than the Federal Clean Water Act, Or Limit Their Authority to Do So
    STATE CONSTRAINTS State-Imposed Limitations on the Authority of Agencies to Regulate Waters Beyond the Scope of the Federal Clean Water Act An ELI 50-State Study May 2013 A PUBLICATION OF THE ENVIRONMENTAL LAW INSTITUTE WASHINGTON, DC ACKNOWLEDGMENTS This report was prepared by the Environmental Law Institute (ELI) with funding from the U.S. Environmental Protection Agency under GSA contract No. GS-10F-0330P (P.O. # EP10H000246). The contents of this report do not necessarily represent the views of EPA, and no official endorsement of the report or its findings by EPA may be inferred. Principal ELI staff contributing to the project were Bruce Myers, Catherine McLinn, and James M. McElfish, Jr. Additional research and editing assistance was provided by Carolyn Clarkin, Michael Liu, Jocelyn Wiesner, Masumi Kikkawa, Katrina Cuskelly, Katelyn Tsukada, Jamie Friedland, Sean Moran, Brian Korpics, Meredith Wilensky, Chelsea Tu, and Kiera Zitelman. ELI extends its thanks to Donna Downing and Sonia Kassambara of EPA, as well as to Erin Flannery and Damaris Christensen. Any errors and omissions are solely the responsibility of ELI. The authors welcome additions, corrections, and clarifications for purposes of future updates to this report. About ELI Publications— ELI publishes Research Reports that present the analysis and conclusions of the policy studies ELI undertakes to improve environmental law and policy. In addition, ELI publishes several journals and reporters—including the Environmental Law Reporter, The Environmental Forum, and the National Wetlands Newsletter—and books, which contribute to education of the profession and disseminate diverse points of view and opinions to stimulate a robust and creative exchange of ideas.
    [Show full text]
  • 2007 Annual Report Building on a Legacy of Leadership 1947-2007
    2007 Annual Report Connecticut Maine Massachusetts Building on a New Hampshire Legacy of Leadership New York Rhode Island Vermont 60th Anniversary New England Interstate Water Pollution Control Commission 1947-2007 New Hampshire Thomas Burack, Esq., Commissioner, Department of Environmental Services Represented by Harry Stewart, P.E., Department of Environmental Services NEIWPCC Officers* NEIWPCC Commissioners* Robert Cruess, P.E., Amherst Nelson Thibault, P.E., Nottingham NEIWPCC 2007 Annual Report Frank Thomas, P.E., Merrimack Chair: Harry Stewart, Connecticut Robert Weimar, P.E., Auburn A Production of the New Hampshire Gina McCarthy, Commissioner, New England Interstate Water Vice-Chair: Alicia Good, Department of Environmental Protection New York Pollution Control Commission Represented by Yvonne Bolton, Esq., Pete Grannis, Commissioner, Rhode Island 116 John Street Department of Environmental Protection Department of Environmental Conservation Treasurer: Richard P. Kotelly, Represented by Sandra Allen, Esq., Lowell, MA 01852 J. Robert Galvin, M.D., M.P.H., Commissioner, Massachusetts Department of Environmental Conservation Department of Public Health p. 978-323-7929 Richard Daines, M.D., Commissioner, Astrid Hanzalek, Suffield Concept/Writer/Project Manager: www.neiwpcc.org Department of Health Stephen Hochbrunn, NEIWPCC Edwin Pearson, Esq., Ridgefield Represented by Richard Svenson, P.E., Department of Health, Environmental Health Protection Cover design and layout elements/design: Maine Albert Bromberg, P.E., Schenectady Cindy Barnard, NEIWPCC David Littell, Commissioner, Leo J. Hetling, Delmar Department of Environmental Protection Layout, design, and production: Represented by Andrew Fisk, Salvatore Pagano, P.E., Clifton Park Ricki Pappo, Enosis – The Environmental Outreach Group Department of Environmental Protection Brenda Harvey, Commissioner, Rhode Island Contributing writers: Department of Health and Human Services W.
    [Show full text]
  • September 2, 2021
    September 2, 2021 Via www.regulations.gov The Honorable Michael Regan The Honorable Jaime A. Pinkham Administrator Acting Assistant Secretary of the Army for U.S. Environmental Protection Agency Civil Works 1200 Pennsylvania Avenue NW Department of the Army Washington, DC 20460 108 Army Pentagon Washington, DC 20310 Mr. John Goodin Director Mr. Vance F. Stewart III Office of Wetlands, Oceans and Watersheds Acting Principal Deputy U.S. Environmental Protection Agency Office of the Assistant Secretary of the 1200 Pennsylvania Avenue NW Army for Civil Works Washington, DC 20460 Department of the Army 108 Army Pentagon Washington, DC 20310 Re: Request for Recommendations on Defining “Waters of the United States” Docket No. EPA-HQ-OW-2021-03281 Dear Administrator Regan, Acting Assistant Secretary Pinkham, Mr. Goodin, and Mr. Stewart: Together, our 85 organizations write to ask you to take two steps to protect critical wetlands, streams, and other waters that we and our millions of members rely on for swimming, fishing, boating, drinking water, and our livelihoods. First, we urge the U.S. Environmental Protection Agency (“EPA”) and U.S. Army Corps of Engineers (“Corps”) (together, the “Agencies”) to promptly restore and implement the regulatory framework in effect prior to the so-called Navigable Waters Protection Rule (“NWPR”). Second, we urge the Agencies to promulgate a new definition of “waters of the United States” that is rooted in science, consistent with Supreme Court precedent, and faithful to the objective of the Clean Water Act.
    [Show full text]
  • In the United States District Court for the District of South Carolina Charleston Division
    IN THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF SOUTH CAROLINA CHARLESTON DIVISION SOUTH CAROLINA COASTAL ) CONSERVATION LEAGUE, CHARLESTON ) WATERKEEPER, AMERICAN RIVERS, ) CHATTAHOOCHEE RIVERKEEPER, ) CLEAN WATER ACTION, DEFENDERS ) OF WILDLIFE, ENVIRONMENT AMERICA, ) FRIENDS OF THE RAPPAHANNOCK, ) JAMES RIVER ASSOCIATION, NATIONAL ) WILDLIFE FEDERATION, NORTH ) CAROLINA COASTAL FEDERATION, ) NORTH CAROLINA WILDLIFE ) FEDERATION, PUBLIC EMPLOYEES ) FOR ENVIRONMENTAL RESPONSIBILITY, ) and ROANOKE RIVER BASIN ) ASSOCIATION, ) ) Plaintiffs, ) Case No. _____________ ) v. ) ) ANDREW R. WHEELER, in his official ) capacity as Administrator of the United States ) Environmental Protection Agency; the UNITED ) STATES ENVIRONMENTAL PROTECTION ) AGENCY; RICKEY DALE “R.D.” JAMES, in ) his official capacity as Assistant Secretary of the ) Army (Civil Works); and the UNITED STATES ) ARMY CORPS OF ENGINEERS, ) ) Defendants. ) _______________________________________ ) COMPLAINT FOR DECLARATORY AND INJUNCTIVE RELIEF 1. Federal law prohibits agencies from reversing national rules based on shifting “political winds and currents” without “measure[d] deliberation” and a “fair grounding in statutory text and evidence.” N.C. Growers’ Ass’n, Inc. v. United Farm Workers, 702 F.3d 755, 772 (4th Cir. 2012) (Wilkinson, J., concurring); S.C. Coastal Conservation League v. Pruitt, 318 F. Supp. 3d 959, 967 (D.S.C. 2018) (“To allow th[is] type of administrative evasiveness . would allow government to become a matter of the whim and caprice of the bureaucracy.”
    [Show full text]
  • Sustainable Management of Wetlands and Shallow Lakes
    Reviving Wetlands – Sustainable Management of Wetlands and Shallow Lakes Guidelines for the Preparation of a Management Plan Global Nature Fund – Living Lakes 1 The project is co-financed by the European Union EU LIFE Programme DG Environment Imprint Global Nature Fund (GNF) Fritz-Reichle-Ring 4 78315 Radolfzell, Germany Ph +49 7732 9995-0 Fax +49 7732 9995-88 E-Mail: [email protected] www.globalnature.org www.livingwetlands.org © GNF 10 / 2004, All rights reserved Editorial Team Marion Hammerl-Resch, Udo Gattenlöhner, Sabine Jantschke with support of Eleni Daroglou, Michael Green, Antonio Guillem, Bettina Jahn, Hans Jerrentrup, Fernendo Jubete Design/Layout Didem Sentürk Printed by Druckcenter Bodensee Photographs GNF-Archive, GNF Project Partners Cover photo Fundación Global Nature (La Nava) If author is not indicated, the texts are written by the Editorial Team. Special thanks to: Fleur Bradnock, Aitken Clark, Rosanne Clark, Maria Conti, Polly Kienle, Julia Masson, Eduardo de Miguel, Gudrun Schomers and Ellen Zimmermann. Recommended citation: U. Gattenlöhner, M. Hammerl-Resch, S. Jantschke, Eds. (2004). Reviving Wetlands – Sustainable Management of Wetlands and Shallow Lakes. 2 Reviving Wetlands – Sustainable Management of Wetlands and Shallow Lakes Global Nature Fund – Living Lakes 3 Contents Preface 6 Introduction 8 1 Initial Situation: LIFE Project Areas 12 2 Who these Guidelines are destined for 16 3 The Management Plan: Need and Background 18 4 Participatory Approach 22 5 Vision 26 6 Legal Responsibilities and the Protection
    [Show full text]
  • Read the Complaint
    2:20-cv-01687-DCN Date Filed 04/29/20 Entry Number 1 Page 1 of 79 IN THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF SOUTH CAROLINA CHARLESTON DIVISION SOUTH CAROLINA COASTAL ) CONSERVATION LEAGUE, CHARLESTON ) WATERKEEPER, AMERICAN RIVERS, ) CHATTAHOOCHEE RIVERKEEPER, ) CLEAN WATER ACTION, DEFENDERS ) OF WILDLIFE, ENVIRONMENT AMERICA, ) FRIENDS OF THE RAPPAHANNOCK, ) JAMES RIVER ASSOCIATION, NATIONAL ) WILDLIFE FEDERATION, NORTH ) CAROLINA COASTAL FEDERATION, ) NORTH CAROLINA WILDLIFE ) FEDERATION, PUBLIC EMPLOYEES ) FOR ENVIRONMENTAL RESPONSIBILITY, ) and ROANOKE RIVER BASIN ) ASSOCIATION, ) ) Plaintiffs, ) Case No. _____________2:20-cv-01687-DCN ) v. ) ) ANDREW R. WHEELER, in his official ) capacity as Administrator of the United States ) Environmental Protection Agency; the UNITED ) STATES ENVIRONMENTAL PROTECTION ) AGENCY; RICKEY DALE “R.D.” JAMES, in ) his official capacity as Assistant Secretary of the ) Army (Civil Works); and the UNITED STATES ) ARMY CORPS OF ENGINEERS, ) ) Defendants. ) _______________________________________ ) COMPLAINT FOR DECLARATORY AND INJUNCTIVE RELIEF 1. Federal law prohibits agencies from reversing national rules based on shifting “political winds and currents” without “measure[d] deliberation” and a “fair grounding in statutory text and evidence.” N.C. Growers’ Ass’n, Inc. v. United Farm Workers, 702 F.3d 755, 2:20-cv-01687-DCN Date Filed 04/29/20 Entry Number 1 Page 2 of 79 772 (4th Cir. 2012) (Wilkinson, J., concurring); S.C. Coastal Conservation League v. Pruitt, 318 F. Supp. 3d 959, 967 (D.S.C. 2018) (“To allow th[is] type of administrative evasiveness . would allow government to become a matter of the whim and caprice of the bureaucracy.” (citations and quotations omitted)), appeal dismissed, No. 18-1964 (4th Cir.
    [Show full text]
  • 09 January 2020 Mr. Thomas Armitage Designated Federal
    09 January 2020 Mr. Thomas Armitage Designated Federal Officer EPA Science Advisory Board (1400R) U.S. Environmental Protection Agency 1200 Pennsylvania Ave. NW Washington, DC 20460 Re: Public Input on Science Advisory Board Commentary on the Proposed Rule Defining the Scope of Waters Federally Regulated Under the Clean Water Act (10/16/19) – “Commentary on Revised Definition of ‘Waters of the United States’ (84 FR 4154)”, Submitted by Members of Previous EPA Science Advisory Board Panel Dear Mr. Armitage: The Science Advisory Board (SAB) currently serving the US EPA provided draft commentary on the proposed rule defining the scope of waters federally regulated under the Clean Water Act (CWA) dated October 16, 2019. As members of the previous EPA SAB Panel that reviewed both the Connectivity Report and the 2015 Clean Water Rule, we respectfully submit the following comments in response to the invitation for public input on this commentary. INTRODUCTORY COMMENTS The intent of the United States Federal Water Pollution Control Act (1972), more commonly known as the Clean Water Act (CWA), is “to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters” (Federal Water Pollution Control Act, 33 U.S.C. 1251 et seq., Sec. 101, p. 3). However, the CWA is notably silent on what constitutes “the Nation’s waters”, more commonly called “waters of the United States” (WOTUS), and the geographic extent of WOTUS subject to regulation under the CWA has been debated for decades between the federal agencies and the regulated public, often adjudicated by the courts. The CWA was clearly intended to cover the traditionally navigable waters (TNWs), such as navigable rivers, lakes, and territorial seas.
    [Show full text]
  • Modeling Connectivity of Non‐Floodplain Wetlands
    JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION Vol. 55, No. 3 AMERICAN WATER RESOURCES ASSOCIATION June 2019 Modeling Connectivity of Non-floodplain Wetlands: Insights, Approaches, and Recommendations C. Nathan Jones , Ali Ameli, Brian P. Neff, Grey R. Evenson, Daniel L. McLaughlin, Heather E. Golden , and Charles R. Lane Research Impact Statement: We utilize four case studies to explore recent advances in process-based model- ing of non-floodplain wetlands in low-gradient, wetland-rich landscapes. ABSTRACT: Representing hydrologic connectivity of non-floodplain wetlands (NFWs) to downstream waters in process-based models is an emerging challenge relevant to many research, regulatory, and management activi- ties. We review four case studies that utilize process-based models developed to simulate NFW hydrology. Mod- els range from a simple, lumped parameter model to a highly complex, fully distributed model. Across case studies, we highlight appropriate application of each model, emphasizing spatial scale, computational demands, process representation, and model limitations. We end with a synthesis of recommended “best modeling prac- tices” to guide model application. These recommendations include: (1) clearly articulate modeling objectives, and revisit and adjust those objectives regularly; (2) develop a conceptualization of NFW connectivity using qualita- tive observations, empirical data, and process-based modeling; (3) select a model to represent NFW connectivity by balancing both modeling objectives and available resources; (4) use innovative techniques and data sources to validate and calibrate NFW connectivity simulations; and (5) clearly articulate the limits of the resulting NFW connectivity representation. Our review and synthesis of these case studies highlights modeling approaches that incorporate NFW connectivity, demonstrates tradeoffs in model selection, and ultimately provides actionable guidance for future model application and development.
    [Show full text]
  • The Clean Water Rule- a Clarification of the Definition Of
    Fordham Environmental Law Review Volume 27, Number 3 2015 Article 3 The Clean Water Rule- A Clarification of the Definition of ‘Waters of the United States’ or Agency Overreach April Collaku∗ ∗Fordham University School of Law Copyright c 2015 by the authors. Fordham Environmental Law Review is produced by The Berkeley Electronic Press (bepress). http://ir.lawnet.fordham.edu/elr THE CLEAN WATER RULE: A CLARIFICATION OF THE DEFINITION OF "WATERS OF THE UNITED STATES" OR AGENCY OVERREACH April Collaku* I. INTRODUCTION - THE CLEAN WATER ACT In the United States, water and water resources are regulated through a mixture of local, state and federal law, regulations and policies. 1 The Clean Water Act (the "CWA" or the "Act") is the primary statute that regulates water at the federal level. 2 Congress passed the CWA in 1972 as an outgrowth and overhaul of the 1948 Federal Water Pollution Act.3 By enacting the CWA, Congress aimed to "restore and maintain the chemical, physical, and biological integrity of the Nation's waters.",4 To achieve this purpose, the CWA generally prohibits the discharge of pollutants5 into waters that fall within the scope of the statute's jurisdiction. * Fordham University School of Law, J.D., Editor-in-Chief, Fordham Environmental Law Review Vol. XXVI. 1. See ENV. L. INSTITUTE, AMERICA'S VULNERABLE WATERS: ASSESSING THE NATION'S PORTFOLIO OF VULNERABLE AQUTIC RESOURCES SINCE RAPANOS V. UNITED STATES, at i (Aug. 2011), available at https://www.eli.org/sites/default/files/eli-pubs/d21-06.pdf [https://perma.cc/BP27- 2PWY]. 2. 33 U.S.C.
    [Show full text]
  • Aquatic Macroinvertebrate Response to Shifts in Hydroclimatic
    AQUATIC MACROINVERTEBRATE RESPONSE TO SHIFTS IN HYDROCLIMATIC VARIABILITY AND ECOHYDROLOGICAL CONDITIONS IN PRAIRIE-POTHOLE WETLANDS: IMPLICATIONS FOR BIODIVERSITY CONSERVATION A Dissertation Submitted to the Graduate Faculty of the North Dakota State University of Agriculture and Applied Science By Kyle Ian McLean In Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Program: Environmental and Conservation Sciences August 2020 Fargo, North Dakota North Dakota State University Graduate School Title AQUATIC MACROINVERTEBRATE RESPONSE TO SHIFTS IN HYDROCLIMATIC VARIABILITY AND ECOHYDROLOGICAL CONDITIONS IN PRAIRIE POTHOLE WETLANDS: IMPLICATIONS FOR BIODIVERSITY CONSERVATION By Kyle I. McLean The Supervisory Committee certifies that this disquisition complies with North Dakota State University’s regulations and meets the accepted standards for the degree of DOCTOR OF PHILOSOPHY SUPERVISORY COMMITTEE: Jon N. Sweetman, PhD Chair David M. Mushet, PhD Craig A. Stockwell, PhD E. Shawn DeKeyser, PhD Approved: 8/14/2020 Craig A. Stockwell, PhD Date Program Chair ABSTRACT Ecosystem degradation and subsequent biodiversity loss has plagued freshwater environments globally. Wetland ecosystems, such as the depressional wetlands found in the Prairie Pothole Region of North America, have been heavily impacted by historical land-use change and continue to be vulnerable to continued landscape modifications and climate change. Using existing literature, I summarized how recent shifts in climate coupled with historic and contemporary landscape modifications have driven a shift in wetland ecohydrological variability. However, clear trends in biodiversity were often limited by the spatial and temporal resolution of published research. I used 24 years (1992–2015) of hydrologic and aquatic-macroinvertebrate data from a complex of 16 prairie-pothole wetlands located in North Dakota to relate wetland ecohydrological variability to biodiversity.
    [Show full text]