英語演講稿水污染英文課件

waterenvironmentwaterenvironment1WateristhesourceofallthingsIt’stheonlywater,butit’stheliquidwonderthatmakesourworldpossible.Waterisabletodissolvemoresubstancesthananyotherliquid.It’stakesalotofwatertokeeplifegoing.Wateristhesourceofallthi2123Somedata

wateruse&pollution

whatcanwedo123Somedatawateruse&pollut3

71%ofearth’ssurface

iscoveredwith

water

Arethewatersources

abundant?71%ofearth’ssurface

4

lessthan3%OftotalwaterLowlayer0.3%offreshwater

lessthan3%Lowlayer0.3%5Chinawaterresourcerankfourthintheworld.Chinaisn'trichinwaterresources.Obviously,theprospectofChinesewaterresourcesisn'toptimistic.WaterIssuesinChinawithwaterresourcespercapitabeing2200m3orso,only1/4ofthatoftheworld.

waterresourcespercapitaChinawaterresourcerankfour6South:

population53%

waterresource:78%North:population:47%waterresource:22%Unevendistributionofwaterresources

South:

population53%

wate7WaterisconsideredpollutedifasubstanceorconditionispresentthatrendersthewateruselessforaparticularpurposeThesourcesofwaterpollutionDirectsourceseffluentoutfallsfromfactories,refineries(精煉廠）,wastetreatmentplants...Indirectsourcescontaminantsthatenterthewatersupplyfromsoils/groundwatersystemsandfromtheatmosphereviarainwater...Waterisconsideredpollutedi8AgriculturalWaterUseFourcommonirrigationmethods:Surface/FloodRequiresextensivecanalsystemsSprayUsepumpsTrickleStrategicallyplacesopeningsSub-irrigationPipescanbeusedfordrainageaswellAgriculturalWaterUseFourcom9Excessivefertilizerusemayleadtoeutrophication（水體富營養(yǎng)化）

inmanyaquatichabitats.Agriculturalrunofffromlarge,openexpansesismajorsourceofwaterpollution.AgriculturalWaterPollutionExcessivefertilizerusemayl10IndustrialWaterUseAccountsfornearly50%ofallwaterwithdrawalinU.S.,and23%worldwide.90%ofwaterusedbyindustryisforcooling,andisreturnedtothesource.Verylittleactuallyconsumed.Mostprocessesinvolveheatexchange.Waterusedtodissipateandtransportwaste.ToxicandoverloadwastesleadStreamandlakedegradation.IndustrialWaterUseAccountsf11IndustrialWaterPollutionAllkindsofindustrygeneratetradewaste(工業(yè)廢水）IronandsteelindustryFoodindustryComplexorganicchemicalsindustryNuclearindustryPollutants:organics,oil,metal,acidMayrequirespecialwastewater

treatment.

IndustrialWaterPollution12DomesticWaterUse70%usedassolventtocarrywastes.30%usedforlawnandgarden.Verysmallfractionusedfordrinking.Naturalpurificationprocessescannotcopewithhighlyconcentratedurbanwastes.Mustbetreatedbeforerelease.DomesticWaterUse70%usedas13DomesticwaterpollutionWastewaterfromBathing,dishes,toiletsNotoxicsubstance,abundantinnutrientswithnitrogen(N，氮）andphosphorus(P，磷）Eutrophication（水體富營養(yǎng)化）Trashorgarbage(e.g.paper,plastic,orfoodwaste)discardedbypeopleontheground,alongwithaccidentalorintentionaldumpingofrubbish,thatarewashedbyrainfallintostormdrainsandeventuallydischargedintosurfacewaters.Domesticwaterpollution14Forgovernments1.Toestablishurbansewagetreatmentsystem(城市污水處理系統(tǒng))2.TorestructureIndustrial3.Toencouragethedevelopmentofnewwatersources4.Tostrengthenlegislation,severepunishmentForgovernments1.Toestablish15Forplants1.Toreducewaterconsumption2.Tobuyequipmentofsewagetreatment3.Don‘tdischargesewageintowater4.TousewaterrecyclingsystemForplants1.Toreducewaterco16Forindividuals1.Don’tusecleanerconcludeP2.Don’tthrowthegarbageintotherivers3.Topromoteawarenessofpreservingwaterresources4.TotellthepersonsaroundyoutoprotectthewaterresourcesForindividuals1.Don’tusecl17WorldWaterDay

(WorldDayforWater)

OnMarch22theUnitedNation