Soil Amelioration and Plant Establishment
on Sodium Affected Soils on Galveston
Island, Texas
Elaine Harris
Dr. Kenneth Farrish, Dr. Dave Creech, and Dr. Leon Young
Galveston Island suffered considerable above-ground damage
from Hurricane Ike in 2008, but the storm surge also caused
longer lasting below-ground impacts in the form of elevated
soil sodium concentrations. High soil sodium concentrations
can be detrimental to soil biology and plant growth. While
sodium can naturally leach out of soil profiles over time, there
are soil management techniques for expediting sodium
remediation that are being evaluated in this study. Principal
methods of elevated soil sodium amelioration include
increasing sodium leaching via irrigation, incorporating
organic mulches, employing elevated planting beds, and
adding chemical amendments. The aim of this study is to evaluate the effectiveness of the soil management
treatments using the survival and growth of three plant species, live oak (Quercus virginiana), hybrid bald cypress
(Taxodium distichum), and yellow hibiscus (Hibiscus hamabo). Current inputs of sodium salts from sea-spray
aerosols and during precipitation events will also be quantified using a precipitation/dry-fall automated collector at
the study site.
Methods
ThestudyareaislocatedincloseproximitytotheOffat’sBayouofGalvestonBayontheMoodyGardens
property.Theexperimentaldesignhastwoplantingrowswhichcontainsevensoilmanagementtreatments
andonecontrol,replicatedsixtimes.Thetreatmentsof
combinationsofincorporatedmulch,gypsum(CaSO4),a
combinationofmulchandgypsum,andconstructedraised
bedsversusflatgroundwererandomlyplacedwithinthe
beds.Plantseedlingswereplantedineachofthebedsafter
theywereconstructed.Soilsamplecoreswerecollected
randomlywithineachbedandtakentotheStephenF.Austin
StateUniversitySoil,Plant&WaterAnalysisLaboratoryfor
analysis.ThemeasuredsoilparametersarepH,electrical
conductivity,exchangeablesodium,calcium,magnesium,
sodiumadsorptionratio(SAR),totalorganiccarbon,and
totalnitrogen.Plantgrowthservesasameansofmonitoringplantresponsetotheappliedtreatments.
Groundlinediameterandtotalheightofeachtreewillbemeasured.Groundlinediameterismeasured
usingadigitalcaliperatthebaseofthetreejustabovetherootcollarandtotalheightisobtainedby
measuringfromthetopoftherootcollartothetipofthedominantstem.APrecipitationCollectorModel
301inthefieldisusedtoevaluateaerialsaltinput(AerochemMetricsInc.,Bushnell,FL).Theinstrument
collectsbothdryandwetdepositionwithasystemoftwopails.Pailsarecollectedandreplacedeveryother
week.Thepailsarethenbroughtbacktothelaboratoryforprocessingandanalysisforsodiumandother
ions.
Results
Preliminaryaerialsodiuminputdataisincluded.(Thedryfall
concentrationfor6/3/16-6/17/16isnotshownduetoa
missingsampleandtheamountofsodiuminthe7/29/168/12/16wetsamplewasnotdetectable).
ThisprojectisfundedbytheMoodyGardensFoundation,theSFADivisionofEnvironmentalScience,and
SFAGardens.
ElaineHarrisispursuingaMasterofScienceinEnvironmentalScienceatStephenF.AustinState
University.ShereceivedherBachelorofScienceinEnvironmentalSciencefromStephenF.AustinState
University.