水域生态学英文

水域生态学英文第1页，课件共31页，创作于2023年2月LenticEcosystemsDepressionsinland1-2,000metersdeepInnorthernhemispheres,glaciersleftbehindcarvedoutbasinsthatfilledwithrainandsnowOthercausesinclude:Silt,driftwoodandothermaterialsthatblocktheflowofstreamsStreamsthatwereflatgetcutofftocreate“oxbows”第2页，课件共31页，创作于2023年2月LenticEcosystemsCratersfromextinctvolcanoesfillwithwater第3页，课件共31页，创作于2023年2月LakeFormationManylakesareformedbyoneoftwomammalsHumans-damriversforpower,irrigation,diggingBeavers-damstreamstoformshallowpondsorlakes第4页，课件共31页，创作于2023年2月LakeLayers3layersEpilimnion-“upperlake”consistsofafreecirculatingupperlayerMetalimnion-alsocalledthermoclineor“middlelake”hasarapiddeclineintemperature(1degreeCelsiusforeverymeteryougodown)Hypolimnion-“lowerlake”isthedeep,colderlayer第5页，课件共31页，创作于2023年2月LakeStructureLittoralzone-shallowwaterzone,lightreachesthebottomanditusuallyhasplantsEmergents-plantswhoserootsandstemsareinwaterbutupperstemsandleavesareoutofthewaterLimneticorPelagiczone-openwater,andhasPlankton-suspendedorganismsNekton-freeswimmingfish第6页，课件共31页，创作于2023年2月LakeZonesBenthiczone-sedimentonbottomoflakesandpondsPhoticzone-wherelightpenetratestothebottomAphoticzone-underwaterareawherelightdoesnotreachEutrophic-nutrientrichOligotrophic-nutrientpoorHypertrophic-excessivenutrients第7页，课件共31页，创作于2023年2月LakeTemperaturesSummer/SpringWateriswarmontopandcoldonbottom第8页，课件共31页，创作于2023年2月LakeTemperaturesFall/winterTemperatureonsurfacedropsandmetalimnionsinksEpilimnionincreasesuntilallwateristhesametemperature\WatercirculatesoxygenandnutrientsOverturn-seasonalmixingofwater第9页，课件共31页，创作于2023年2月WaterChemistryDissolvedOxygen(DO)EntersthewaterthroughtheatmosphereandphotosynthesisAmountofoxygenthewatercanholddependsonpressure,temperature,andsalinityColdwaterholdsmoreoxygenthatwarmwaterAsatmosphericpressureincreases,sodoestheamountofoxygeninthewaterOxygenabsorbedbythesurfaceismixedbyturbulenceofinternalcurrentsOverturnreplenishesoxygeninthewater第10页，课件共31页，创作于2023年2月WaterChemistryCarbonDioxideCarbondioxideisusuallythesameconcentrationasthatintheatmosphere第11页，课件共31页，创作于2023年2月WaterChemistrypHAmeasureoftheacidicorbasicthewaterisOnascaleof1-141isveryacidicand14isverybasic7isneutralFreshwater3-10Rainwater5-6Streamsandlakes6.5-8.5LimestoneunderthewatercausesthepHtoincrease(orbecomemorebasic)第12页，课件共31页，创作于2023年2月LoticEcosystemsFlowingwater(riversandstreams)VelocityandcurrentdecidemostthingsbecauseitcutschannelsandaffectslivingorganismsVelocityisdeterminedbysize,shape,gradientofthechannel,roughnessofbottom,depth,andprecipitation第13页，课件共31页，创作于2023年2月StreamsMaybeginasoutletsofpondsorlakesFlowisdeterminedbythelayofthelandifthestreamhasnotbeendisturbedAswaterflows,itpicksupdebristhatscrapesthebottomandmakesthestreambigger第14页，课件共31页，创作于2023年2月TermsMeander-bendsinstreams(aka.Sinuosity)Watershed-bodyoflandwhereallrunoffcollectsinacommonbodyofwaterTurbidity-theamountofparticlessuspendedinwaterprohibitinglighttoshinethroughChannel-thestreambedandbanksformedbyflowingwaterFloodPlain-astripoflandthatisnormallydryandflatthatisonthesidesofariverorstreamandiswetduringfloods.第15页，课件共31页，创作于2023年2月TermsRiparianZone-thelandandvegetationborderingflowingorstandingwaterRiffle-asectionofastreamwherethewaterisshallow,fastmoving,andisbrokenintowavesbyanobstructionSiltation-depositionoffineparticles(silt)onthebedsofstreamsorlakesPools-waterthatisrelativelydeepBankfullWidth-wherewaterwillstopifitcomesoutofthestream第16页，课件共31页，创作于2023年2月Howcanyoutellifastreamishealthy?StreamQualityisdeterminedbyAreacover Dothingshangoverthestream?Embeddedness Aretheredirtparticlesonthebottom?Depth Isthestreamshallowordeep?Sedimentdeposits Aretheresedimentbuildups?Channelflow Doeswaterfillupthechannel?第17页，课件共31页，创作于2023年2月Streamqualitycontinued…ChannelAlteration Hasconcrete,rock,oranythingelsebeenaddedtothestream?Frequencyofrifflesorbends Doesthestreamcurveorhaveanywhitewater?Bankstability Arethebanksfallingintothestream?VegetativeProtection(onthebanks) Arethereplantsgrowingonthebanks?Riparianzonewidth Howbigistheareaonthebankwhereplantsgrow?第18页，课件共31页，创作于2023年2月第19页，课件共31页，创作于2023年2月StreamChemistrypHArangeof6-9isidealforrunningfreshwaterfishandbottomdwellinginvertebratesSynergisticEffectsHappenswhentwothingscombinetoproduceeffectsgreaterthantheirsum Example.)PollutantscanchangethepHofastream第20页，课件共31页，创作于2023年2月StreamChemistryDissolvedOxygen(DO)Ifdissolvedoxygendropsbelow5mgperliter,aquaticlifeisstressedThelowertheconcentration,themorestressLevelsbelow1-2mgperliterforafewhoursresultin“fishkills”第21页，课件共31页，创作于2023年2月StreamChemistryBOD(biochemicaloxygendemand)TheamountofoxygenneededfordecompositionIfthereislittleoxygen,decomposersthatuseitwilldieToomuchoxygencauses“gasbubbledisease”RareOxygenblocksbloodvesselsCanseebubblesonthefinsandtheskin第22页，课件共31页，创作于2023年2月第23页，课件共31页，创作于2023年2月StreamOrdersStreamsjointogethertoformrivers.Eachtimeonestreamjoinsanother“order”changes.Afirstorderstreamisonethatdoesnothaveanyotherstreamjoiningit.Astreamcanonlyincreaseinorderifastreamofasimilarorderjoinsit.Forexample,whenafirstorderstreamrunsintoanotherfirstorderstream,itbecomesasecondorderstream.Likewise,whentwosecondorderstreamsjoineachother,itbecomesathirdorderstreamandsoon.第24页，课件共31页，创作于2023年2月StreamOrdersOrderisnotincreasedwhenalowerorderstreamjoinsoneofalargerorder.Generally:FirstthroughthirdorderstreamsareusuallycalledheadwaterstreamsFourththroughsixthorderstreamsareusuallycalledmedium-sizedstreamsAbovesixthorder,thestreamsbecomeriversLowerorderstreamsareusuallyonsteepslopescomparedtohigherorderstreamsHigherorderstreamshavefloodplains第25页，课件共31页，创作于2023年2月Awatershedisasectionoflandwhereallthewaterrunoffflowsintoacommonbasin.第26页，课件共31页，创作于2023年2月StreamRestorationTherearemanyaspectstostreamrestoration,butsomesuggestionswouldbe:Decreasetheslopeofthebanks(ifitwillnotcompromiseoreliminatetheriparianzone).Thisisgenerallyaccomplishedbyusinga3:1ratio.Stream3ft.1ft.BankReducesthestressonchannelwallsfromflowingwaterBecomesmorestableStopserosionandsedimentationCreatesasurfaceforvegetation

Stream3ft.1ft.Bank第27页，课件共31页，创作于2023年2月StreamRestorationStabilizetheStreamBanksRiparianForestationPlantnativevegetationonthestreambankstostoperosion.Therootsoftheplantswillholdthesoilontothebanks.Addbigstructurestothebankslikewood,stone,orfabricthatwillnotwashaway.Fabricprovidesasurfacetoholdplantedvegetation.Drivepostsintothebanktokeepsoilfromerodingintothestream.Makethechannelbigger.第28页，课件共31页，创作于2023年2月StreamRestorationConstructrifflesandpoolsAddinglargerocksand/orothermaterialsfromthesitetothestreampreventsnaturalareasfrombeingdisturbedby