Greenhouse EffectCarbon FootprintGlobal WarmingGasesFossil FuelsMethaneEnergy-Generating ResourcesRenewable EnergyForestryClimate ChangeAtmosphereCrops, AgriculturalConservation of Natural ResourcesAgricultureEnvironmental PolicyConservation of Energy ResourcesCarbon DioxideBiofuelsClimateNitrous OxideCarbonEnvironmental MonitoringSoilAir PollutantsEcosystemAir PollutionModels, TheoreticalTreesBiomassDenitrificationFertilizersCarbon SequestrationEarth (Planet)Waste ManagementGasolineEnvironmental PollutionNitrificationVehicle EmissionsEnvironment, ControlledEnvironmental RemediationNitrogen CycleLivestockOceans and SeasGardeningGarbageRefuse DisposalWetlandsTropical ClimateFiresCarbon CycleIce CoverTemperatureHuman ActivitiesPositron-Emission TomographySoil MicrobiologyEnvironmentNitrogenOtoacoustic Emissions, SpontaneousSeasonsFood SupplyTomography, Emission-ComputedEcological Systems, ClosedOzoneSeawaterNitrogen OxidesChromatography, GasForecastingGas Chromatography-Mass SpectrometryAnimal HusbandryGeographyFluorodeoxyglucose F18RadiopharmaceuticalsAmmonia