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Carbondioxide(CO
2
)isabsorbedbyland and vegetationthroughtheprocessofphotosynthesis.The
netemissionsarenegative(sequestration) and substantial,offsettingapproximately884MMTCO
2
E,or
approximately13%oftotalemissionsin2006.
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Thecarbonsequestration and storageprovidedby
landcanbepreservedthoughsustainablelandmanagementpractices, and canbeenhancedby
restorationofland,suchasreforestationofcontaminatedland.
Theemissionsestimatefortheland‐basedcarbonsinkisgivenbytheInventory.Specifically,Chapter7,
LandUse,Land‐UseChange, and Forestry,providesanassessmentofthenetGHGfluxresultingfrom
theuses and changesinlandtypes and forestsintheU.S.,includingnetemissionsfromforestland
remainingforestland,croplandremainingcropland,landconvertedtocropland,grasslandremaining
grassland,landconvertedtograssland,settlementsremainingsettlements,landfillyardtrimmings, and
...
REDUCINGORAVOIDINGGHGEMISSIONSTHROUGHLANDMANAGEMENTPRACTICES
Landmanagementdescribeshowwemanage and uselandtoprovideopenspace and habitat,food,
naturalresources, and placesforpeopletolive,work, and recreate.EPApromotesintegratedland
managementstrategiesthatuselandasproductively and sustainablyaspossiblebypromotingsmart
growth,preventing and minimizingtheoccurrenceofcontamination and bycleaningup,reusing, and
restoringcontaminatedlandforbeneficialreusebycommunities.
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AsdescribedinBox7,landmanagementhasthreekeycomponents:landprotection,sustainableland
use, and landrevitalization.Similartothematerialsmanagementapproachesthatcanbeusedinthe
materialflow,landmanagementapproachescanbeusedtoreduceGHGemissionsbyimproving
practiceswithinoracrosseachofthesecomponents.Landprotectionpracticeslimithowmuchlandis
contaminatedeachyear.Whenlandiscontaminated,itshouldbe
cleaneduptolevelsprotectiveofhumanhealth and the
environment.
Land ... September2009
growth.
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Thisremediationapproachalsoprovidesauseforsomeorganicsoilamendmentssuchas
biosolidswhichmayotherwisebeawasteproduct.
LandcleanupactivitiesmayalsoproviderecyclingopportunitiestofurtherbolsterEPA’sapproachesto
materials and landmanagement.Forexample,reusing and recyclingconstruction and demolition
debrisfrombuildingsoncontaminatedlandisanothereffectivematerials and landmanagement
practice; this practice notonlyreusesbothmaterials and land,butalsopreventsotherlandfrombeing
usedforthedisposalofconstruction and demolitiondebris.
Aftercleanupiscomplete,sustainablyreusinglandprotectstheland‐basedcarbonsink,byproviding
sitesthatcanbereusedfordevelopment,insteadofdevelopinggreenfields.Reusingtheserestored
propertiescanalsoreduceGHGemissionsassociatedwiththeinfrastructureexpansionneededto
connectnewlydevelopedgreenfieldstoalreadydevelopedareas.Policiesthatpromotelandreusein
placeofnewlanddevelopment and densermixed‐usedevelopment—keyaspectsofsmartgrowth—
willavoidthemajorityofinfrastructure and bio‐carbonemissions.Sitescanalsobeecologically
restoredtoincreasetheamountofundevelopedland and expandtheland‐basedcarbonsink.
Inaddition,severalEPAprogramsfocusonsustainablecleanup and redevelopmentofcontaminated
land,includingenvironmentallyresponsiblelandscaping,energyefficientstructures,greenbuildings,
and greenremediation,
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whichcanallfurtherreduceGHGemissions.Manycontaminatedproperties
alsohaverenewableenergydevelopmentpotential and arelocatednearexistingutility
infrastructure.
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And ofcourse,preventingcontaminationinthefirstplaceavoidstheneedforcleanup
activitiesorgreenfielddevelopment.SeeBox8forexamplesoflandmanagementapproachesthat
helpreduceGHGemissions.
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Carbon...