z,go-w-98-O02 LOANCOPY ONLY Recent ResearchIn Coastal Louisiana: Natural System Functionand Respo Human Influenc A Symposium 1998 Thissymposium was funded by generousgrants and support from the Louisiana UniversitiesMarine Consortium LUMCON!, Louisiana Sea Grant Program, Coastal Ecology instituteof LouisianaState University, Louisiana Environmental Research Center of McNeese StateUniversity, U.S. Environmental Protection Agency, U.S, Geological Survey in Baton Rouge,NOAA Coastal Services Center, Louisiana Department of Natural Resources, LUMCON Foundation,inc., T. BakerSmith and Sons,inc., andthe Coalition to RestoreCoastal Louisiana. Themeeting was planned and organized byDenise Reed, Nancy Rabalais, John Day, Andy Nyman,Ed ProAitt, Lawrence Rozas, Gary Shaffer, and Gene Turner. We thank the presentcrs andattendees forsharing their research, staying onschedule, andallowing stimulating discussion.Thefollowing persons assisted tremendously inthe preparation ofthis volume by reviewingthe manuscripb presented here: Clark Alexander, Jim Allen, Mahalingarn Baskaran, AaronBass, Thomas Bianchi, Donald Boesch, Kirk Bundy, Donald Cahoon, Dan Childers, RobertChristen, Robert Costanza, Sherri Cooper, John Dingier, Quay Dortch, Mike Durako, KeithEdwards, Steve Farber, Miriam Fearn, Mark Ford, Jon French, Gary Gaston, Robert Grambling,Courtney Hackjney, KenHeck, Fred Hitzhusen, ClintJeske, Barb Kleiss, Dwight LeBlanc,Paul Leberg, Terry Logan, Lynn Leonard, Karen Manel, Brent McKee, Thomas Minello,Cynthia Moncrief, Hillory Neckles, William Nuttle, Chris Onuf, Jonathan Pennock, GaryRay, Harry Roberts, Rickey Ruebsarnen, GaryShaffer, Charles Simenstad, Fred Sklar, DonnySmoak, Thomas Soniat, Marilyn Spalding, Karen Steidinger, Judy Stout, Eric Swenson, RobertTWilley, ivan Valie!a, Milan Vavrek, Shio Wang, James Webb, and Erik Zobrist. We greatlyappreciate theefforts ofBonnie Ducote with the Louisiana SeaGrant CoBege Program forher work on the production of this volume. LOUlSlANA Publishedbythe Louisiana SeaGrant College Program, apart of the National SeaGrant College Programmaintained bythe National Oceanic andAtrnosphenc Administration ofthe U.S. Department of Commerce. 1999. Louisiana Sea Grant CommunicationsOffice LouisianaState University BatonRouge, LA 70803-1507 225-388-6449 FAX 225-388-tt331 Website: httpJ/www.laseagrant.org PREFACE Thecoa»tal barriers, bays, mar»hes, and swamps of Louisianacompose one of thelargest deltaicsystems of the world. In contrasttomany other deltas on Earth, where wetland» have beendrained and barrier islands built upon, the MississippiDelta Plain i». still a highly productiveecosystem. It i»,however, a systetn that had been dramatical]y altered from it» natural stateand a placewhere the challenges of managing and sustaining ecosystem function are faced everyday. The research community in Louisiana hasfor many years been at the forefront in dealingwith management issue» and ensuring that decisions are made on the basi» of thehe»t availablescience, ln thelast decade with the advent of a large-scalewetland restoration program underthe Coastal Wetlands Planning Protection and Restoration Act, with increasedawareness ofthe potential consequences ofriver diversions, andwith a renewedeffort to exploit subsurface mineralresources in the coastalzone, it hasbecome essential that the research conununity be proactiveindisseminating themost current scientific understanding tocoastal managers and decision makers. Withthis in mind,we convened a broad-basedcommittee from amongst the research communityworking incoastal Louisiana todesign a coastal research meeting. The goal was to provideanopportunity fordissemination anddiscussion ofresearch findings among scientists, managers,andpolicy makers. The result was the conference 'Recent Research in Coastal Louisiana:Natural System Function and Response toHuman Influences'. Theconference was heldin February]998 in Lafayette,Louisiana. Over three days, 48 oral and 20 poster presentationsweremade toan audience ofover 150 people. Plenary presentations byCharles Simenstadon wetland restoration in thePacific Northwest and Ron Jones on thechallenges of ecosystemmanagement inthe Florida Everglades provided a context forus to consider the problemswe facein coastalLouisiana, Theconference wasa great success, andthe papers in this volume represent apartial recordof thediscussions that occurred Scientific advances will continueand our understanding ofsystem function will only increase. Inthat sense, theinformation presented hereis a snapshot of thestate of coastal science knowledge in the late 1990'». There are few venues where managersandresearchers canopenly discuss their observations, findings, anddoubts. Perhap» moreenduring, therefore, isthe recognition thatwe all share a commongoal of a sustainable. productivecoastal Louisiana and that the best efforts of all are needed toget there. This publicationshould be citedas: Rozas,L.P, J.A, Nyrnan, C.E. Proffitt, N.N. Rabalais, D.J. Reed, and R,E. Turner editors!.1999. Recent research incoastal Louisiana: Natural »ystetn function andresponse tohuman influences. louisiana Sea Grant College Program, Baton Rouge, LA. TABLE OF CONTENTS PAGE ACKNOWLEDGMENTS . PREFACE ..... HYDRODYNAMICS AND SEDIMENTARY PROCESSES Hale, L, M.G, Watdon,C,F. Bryan, and PA. Richards Historicpatterns of sedimentationin Grand Lake, Louisiana Ketnp,G. PJ. W. Day, JrD.J, Reed, D,R. Cahoon, and Af. Wang Sedimentation.consolidation andsurface elevation change in twosalt marshes ofthe Mississippi River deltaic plain: Geotechnical aspects of wetland loss, Pepper,D.A., G.W. Stone, and P. Wang A prelitninary asses sment of wave, current, and sediment interaction on the Louisianashoreface adjacent to the isles Dernieres Meselhe,E.A.. A,A. Bradley, A. Kruger,and M. VL Muste ParticleImage Veloeimetry PIV! and numerical modeling for flow estimationand analysis, ...............,....................,....................,....... Mendelssohn.LA. and JV.l Kuhn Theeffects of sediment addition onsalt marsh vegetation and soil physi co-chemi stry ...55 WATERQUALITY AND ENVIRO%VIENTALCHEMISTRY Parsons,hl,L, 0. Dnrtch,R.E Turner,and h/,A'.Rabalai s Theuse of di«tom remains asa proxyofhistorical salinity changes in AirplaneLake, Loui siana, Waldon,M.G. andC,F. Bryan Annualsalinity and nutrient budget ofLake Pontchartrain andimpact of theproposed Bonnet C~ diversion.......,....................,...,................. ... 79 Day,J,W, Jr., R.R. Lane, R.F. ltfach, C.G. Brantley, and M,C. Daigle Waterchemistry dynamics inLake Pontchartrain, Louisiana, during the 1997opening of theBonnet Carre Spillway ..................,.............-...,."--"- Ri-~o,WM. and R.G. Boustany Sediment-watermaterial fluxes in benthic microalgal-dominat<xt sediments from beds ofsubmersed vegetation: Impacts of lightreduction and nutrient enrichment ... 101 PAGE Boustarii; R,G, and W,M Ri=-o Wholesystem material fluxcs within meadows of Vai isnertaamericana from Lake Pontchartrain,LA: Effects of light and nutrient manipulations, Pr>irrier,Af.A., B. Afagiic. J.C, Francis,C.D. Fran e, and 8.-J, Cho Effectsof the1997 Bonnet CaW Spillwayopening on Lake Pontchartrain submersedaquatic vegetation Dortch, QM.L Parse>nt,H.X. Rabaiais,and R.F. Turner What is thethreat of harmfulalgal blooms in Louisianacoastal water." Turner, R.E. Nitrogenlosses in waterflowing through Louisiana swamps ... Day.J. W, JrJ.M. Rybc-vk, L Cardoch,WH. Conner,P. Delgado-Sanche R.l. Pratt, and A. Westpha A reviewof recentstudies of theecological and economic aspects of the applicationof secondarily treated inunicipal effluent to wetlandsin southern Louisiana Gauthreaux,K, J, Sneddon,TAf. Falgoust, Af.J. Beck, and J.N. Beck Migrationof speciatedmetals in soils reclaimed from ship channel sediments,.. 167 COASTAL LAND LOSS AND WETLAND RESTORATION Turner, R.F.. Wetlandloss in theBarataria Estuary; Empirically-defined relationships and multiple workinghypotheses ......,.,...,.............., 183 Day,J.W. Jr., G.P. Shager, LD. Britsch,D.J. Reed, XR, Hau>es, and D. Cahoon Patternand process of land loss in the Louisiana coastal zone: An analysisof spatialand temporal patterns ofwetland habitat change .., 193 Reyes,F., J,F, Afartin, ML White,J.W. Day Jr., and. G.P, Kemp Landscapemodeling mcoastal Louisiana: Regional mechanisms of '7P3 land loss Pmfgtt, C.E, andJ. Young Saltmarsh plant colonization, growth, and dominance onlarge mudAats createdusing dredged sediments . 21g Turner, R.E Low-costwetland restoration and creation projects for coastalLouisiana. PAGE WETLAND MANA GEMKNT Bote~eois, J.A. artdE.C Webb Effectsof weirs on the depth and duration of flooding in a Louisianamarsh ., ... 241 Hess,X J.J G.E.Melan on,B.C. Wilson, and C,M, Witsd!tarn Emectof 3-D seistnic vehicular traffic on marsh soil elevations in a SouthwestLouisiana coastal marsh ... 254 Wilson,8.C., T,J.Hess Jr., M. C, Wittdhatn, and 8.E. hfoser EfFectof 3-Dseismic on vegetation ofa SouthwestLouisiana coastal marsh . ... 262 Rnberts,K,J., PA. Coreil, and A,J, Ortega, Jr. Taxationofprivate marshland: Theuse of value method applied to Lou i siana's coast ... 270 COASTAL FLORA AND FAUNA Stickle, 8!8. Jr, Effectsofestuarine environmental factorgradients onthe tolerance and physiologyofthe southern oyster drill, Stramonita =Thais! !taemastotna: Anitnportant predator ofthe American oyster, Crassostrea virginica........... , 277 Fleun',B,E, T.WSlterry, and J.V. Htitter Agriculturalwetlands andthe conservation ofcolonial wading birds in Louisiana ... 287 Visser,J,M.. F. Frankeri,arid C.E, Sasser Effectsofgrazing