ns5 lecture 1 part 1

ECOSYSTEMCONCEPTSandECOLOGY

BasicConceptsand

Principles

2DepartmentofBIOLOGY,CAS‐UPManila

• Earthistheonlyplanetwherethereislife.

• WhydoesEarthhavewind,clouds,andrain?

• WhydoesEarthhaveweatherelementswhichthemoonandotherplanetsdonothave?

• Themostimportantfactorsthatmakeweatherchangespossiblearesun,air,andwater


• Earth’sperfectsizeandmass,crucialtoaplanet’sabilitytodevelopanatmosphereandsustainlife

• “Anotherfascina;ngcoincidenceisthatonlyatmosphereswithbetweentenandtwentypercentoxygencansupportoxida;vemetabolisminahigherorganism”(Nature’sDes+ny)

• Ourexis;ngmagne;cfieldcreatesakindof“forcefield”aroundourplanet,protec;ngusfromdirectinterac;onwiththesun’ssolarwind—whichcouldblowawayouratmosphereandwithittheabilitytosustainlife

DepartmentofBIOLOGY,CAS‐UPManila 4

• CommunityoflivingthingsontheEarth

• SumofallecosystemsonEarth

• LivingorganismsofthebiospheredependononeanotherandontheotherdivisionsoftheEarth’sphysicalenvironment:– ATMOSPHERE(gaseousenvelope)– HYDROSPHERE(watersupply)– LITHOSPHERE(crust:soilsandrocks


• TheEarthenvironmentisthehome(habitat)ofallformsoflifeincludinghumans.

• Alllifeformsdependontheproperfunc;oningofourenvironment!

• Toappreciatetheintricaciesandimportanceoftheenvironment,however,itisnecessarythatcertainecologicalprinciplesbeexplained


Humans are biological organisms, all our

activities have a bearing on ecology

“Justaswehumansareconstrainedbythelawsofphysicswhenwebuildairplanesandbridges,weshouldalsobeconstrainedbytheprinciplesofecologywhenwealterthe

environment”

• CoinedbyErnstHaeckel(1869)

• “oikos”–house• “logos”‐studyof

• EARTHislikeagreatestateinwhichthelivingorganismsandthephysicalenvironmentinteractinanimmenseandcomplicatedwebofrela;onships

• ECOLOGY,then,isthestudyoftheinterac;onsamongorganismsandbetweenorganismsandtheirphysicalenvironment


• Rela;onshipwithEcology– Study of the interrelationship between

living organisms and their animate and inanimate environment

• Ecologyisthebasictoolofenvironmentalscience


ECOSYSTEM–basicunitandprobablythemostimportantconceptinecology

TwoTypesofSystem:1. Opensystem–

presenceofinputsandoutputs(maUerandenergy)

3. Closedsystem–noexchangeofmaUerandenergy(usuallyarXficiallymade,e.g.


• NEGATIVEFEEDBACKMECHANISM– Bringsthesystembacktotheidealstate– Devia;on‐counterac;nginputs

• Homeosta;cPlateau‐min/maxareawithinwhichthenega;vefeedbackmechanismcans;llfunc;on

• POSITIVEFEEDBACKMECHANISM– Increasingtendencytobeawayfromsetpoint– Devia;on‐accelera;nginputs– Homeosta;cplateauexceeded

• Ex.Geometricincreaseinthepopula;on» Developmentofcancerandkidneystones» Parturi;onorchildbirth


DOYOUTHINKTHISISANECOSYSTEM?


BIOTICCOMPONENTS ABIOTICCOMPONENTS• Producers

– GreenPlants– Algae(Phytoplankton)

• Consumers– Herbivores– Carnivores– Omnivores

• Decomposers– Detri;vores– Truedecomposers

– Bacteriaandfungi

• Clima;cFactors– Light– Temperature

– Precipita;on– Wind

– Humidity

• EdaphicFactors– SoilNutrients– SoilMoisture

– SoilPh• HydrologicalFactors

– PhysicochemicalfactorDepartmentofBIOLOGY,CAS‐UPManila 12

THEABIOTICFACTORS


• Lightaffectsthefollowingac;vi;es– rateofphotosynthesis(blueandred420‐660nm)

– flowering,dormancy,andleaffall

– migra;onandhiberna;on– nes;ngbehavior

• Temperature– directeffectonmetabolismbycontrollingbodychemistryand

reac;ons(incTincrateofreac;ons)

– affectsotherenvironmentalfactorssuchasmoistureavailability


• Precipita;on/Moisture– Waterasauniversalsolvent,mediumforbiochemical

processes– Verylimi;nginterrestrialenvironment;determinesthetype

ofvegeta;oninagivenenvironment

• Atmosphere/Wind

– Majorreservoirofnutrientsimportanttolife

– Windac;onacceleratestranspira;onprocess– Strongwindsmayinducephysicaldamageonplantstructure

anddistribu;onofseedsandsmallanimals


• SoilContent– Morenutrientsinsoilforplantgrowthmeansgreaterproduc;vity– “LawoftheMinimum”byJustusvonLiebig(1837),thegrowth

andsurvivalofplantsdependonthenutrientthatisleastavailable

• SoilMoisture– Increasewateravailabilitygenerallymeansgreaterproduc;vity;

waterisarawmaterial

• SoilAcidity– determinesthesolubilityandavailabilityofessen;alinorganicsalts

inthesolu;on


• Canmodifytheclima;cfactorsintheenvironmentespeciallylight,temperature,moisture,andpressure– Al;tude–dropof5.5˚Cper1000mincrease

inal;tude

– Aspect–north‐facingslopeandsouth‐facingslope(lowmoisture,highT,highevapora;on)


THEBIOTICFACTORS


• AgroupsoforganismsthatcanusetheenergyinsunlighttoconvertwaterandcarbondioxideintoGlucose(food)

• AutotrophsarealsocalledProducersbecausetheyproduceallofthefoodthatheterotrophsuse

• Withoutautotrophs,therewouldbenolifeonthisplanet

• Ex.PlantsandAlgaeDepartmentofBIOLOGY,CAS‐UPManila 19

• Autotrophsthatgettheirenergyfrominorganicsubstances,suchassalt

• Livedeepdownintheoceanwherethereisnosunlight

• Ex.BacteriaandDeepSeaWorms


• Organismsthatdonotmaketheirownfood

• AnothertermforHeterotrophisconsumerbecausetheyconsumeotherorganismsinordertolive

• Ex.Rabbits,Deer,Mushrooms


• Scavengers/Detri;vores–feedonthe;ssueofdeadorganisms(bothplansandanimals)

– Ex.–Vultures,Crows,andShrimp

• Herbivores–eatONLYplants– Ex.–Cows,Elephants,Giraffes

• Carnivores–eatONLYmeat

– Ex.–Lions,Tigers,Sharks

• Omnivores–eatBOTHplantsandanimals

– Ex.–BearsandHumans


4LAWSOFECOLOGY

1. EVERYTHINGISCONNECTEDTOEVERYTHINGELSE

2. EVERYTHINGMUSTGOSOMEWHERE

3. NATUREKNOWSBEST

4. THEREISNOFREELUNCH


HOWDOESANECOSYSTEMWORK?


• Significance:makesenergyavailabletoallcomponentsoftheecosystem

• Nature:“unidirec;onallinearflow”» “Ma0ercirculatesenergydissipates”

• TwoLawsofThermodynamics–governsthe“one‐way”flowofenergythroughtheecosystem


• Whenazebraeatsthegrass,itdoesnotobtainalloftheenergythegrasshas(muchofitisnoteaten)

• Whenalioneatsazebra,itdoesnotgetalloftheenergyfromthezebra(muchofitislostasheat)

• Thetwo(2)previousexamplesofenergytransfershowthatnoorganismEVERreceivesalloftheenergyfromtheorganismtheyjustate

• Only10%oftheenergyfromonetrophiclevelistransferredtothenext–thisiscalledthe10%law


• GrazingFoodChain

– startsfromagreenplantbasethengoestograzingherbivores,andontocarnivores;– mostcommonindeepaqua;csystemsbutcanalsobefoundinterrestrial

• grasscowman• phytoplanktonzooplanktonplank;vorespiscivorescatdog“lasenggo”

cannibals

• DetritalFoodChain

– fromdeadorganicmapertomicroorganismsandthentodetri;voresandtheirpredators– mostcommoninterrestrialandshallowwaters

• deadleavesmitescarnivorousmites• dungbacteriamicrobialconsumers

• Parasi;cFoodChain

– Inwhicheithertheproducerorconsumerisparasi;zed– Foodpassestoasmallerorganismthanalargerone.

• e.g.termitesTriconympha


• MostorganismseatmoretheJUSToneorganism

• WhenmoreorganismareinvolveditisknowasaFOODWEB

• Foodwebsaremorecomplexandinvolvelotsoforganisms


No;cethatthedirec;onthearrowpoints→thearrowpointsinthedirec;onoftheenergytransfer,NOT“whatatewhat”

• Anecologicalpyramidshowstherela;onshipbetweenconsumersandproducersatdifferenttrophiclevelsinanecosystem

• Showstherela;veamountsofenergyormapercontainedateachtrophiclevel

• ThePyramidshowswhichlevelhasthemostenergyandthehighestnumberoforganisms


• Thetotalmassoftheorganicmaperateachtrophicleveliscalledbiomass

• Biomassisjustanothertermforpoten;alenergy–energythatistobeeatenandused.

• Thetransferofenergyfromoneleveltoanotherisveryinefficient(10%Law)


BiogeochemicalCyclingintheEcosystem

Allmapercycles...itisneithercreatednordestroyed...


• Definedasthemovementofelementsandcompoundsthatareessen;altolife– Materialsaretransportedthroughorganisms,theatmosphere,waterandlandinaseriesofCYCLES

• “Bio”–life,par;cipa;onoforganisms

• “Geo”‐abio;cenvironmentassourceofnutrients• “Chemical”–natureofsubstancesbeingcycled

“Biogeochemistry”(GEHutchinson)DepartmentofBIOLOGY,CAS‐UPManila 33

• Gaseoustype–thereservoiristheatmosphereand/orhydrosphere(e.g.N2,CO2,O2)

• Sedimentarytype–thereservoiristheEarth’scrust(e.g.Phosphorus)

• Linkagetype–thereservoirincludesmajorpathwaysinair,water,andcrust(e.g.sulfur)


• Pollu;on–accumulaXonofachemicalformthatishigherthanthestandards

• Non‐biodegradablesubstances–changetoformnewchemicalstructurewherenoorganismhasyettouXlizeit

• ReducXonoftheconcentraXonofotherchemicalforms–limitsgrowthofthesubsequentcomponentsofthecycle

• Eutrophica;on‐thechannelingofasubstancetootherpathways(greateramountsofphosphatesinaquaXcsystems)


• FlowofH2O

• Mediatesnutrientcycleandasmajorenergydissipa;onpathway

• Processes– Precipita;on– Run‐offandinfiltra;on– Evapora;on– Condensa;on


• Freshwater– 3%oftheworld’swatersupply

• Moreconsump;onthansupply

• Pumpingwatersfromaquifers‐notanormalpartofthewatercycle

• Garbageandwastespollutethewaterandclogdrainagesystemsinducesflooding

• Asphal;ng–renderthegroundimpervioustowaterblocksinfiltra;on


Pollu;on

–achangeintransferrateofwaterandnutrientsthatcanleaddirectlyorindirectlytoadegradaXonofhumanhealthordegradaXonof

plantandanimallife

• Type:Gaseous(21%)

• MajorReservoir:Atmosphere

• Forms:FreeandMolecularOxygen

• Sources:– Photosynthesisfromproducers– PhotodissociaXonofWaterVapor

• FateofFreeO2:1. Reachhigherlevelsoftrophosphereandreducedtoozone

(providesprotecXonbyfilteringoutthesun'sUVrays)2. Mayreactwithchemicalsandorganiccompoundsofthe

earth’scrust3. MaybeusedupincellrespiraXonwhichreleaseCO2tobe

usedbyautotrophstoproducemoreO2


• CFC’s(chlorofluorocarbons)depleteozonelayer“ozonehole”

• Eutrophica;on(nutrientenrichmentfromagriculturalanddomesXcwastes)leadstodepleXonofoxygeninwater

• Combus;onoffossilfuelsandremovalofvegetaXon(deforestaXon)depletethesupplyofoxygenintheatmosphere


• Type:GaseousCycle

• MajorReservoir:Atmospherebutalsocalciumcarbonateinshellsandlimestone,aswellasfossilfuels

• Significance:Majorelementoforganiccompounds;buildingblocksofallbiomolecules

• Processes– PhotosynthesisremovesCO2whilerespiraXonandcombusXonaddCO2

totheatmosphere.– CO2fromairandwatercombinetoformbicarbonate(HCO3)–sourceof

carbonforaquaXcproducers.Carbonicacidmakesrainwateralsoslightlyacidic.

– Similarly,whenaquaXcorganismsrespire,CO2isreleasedandcombinewithwatertoformHCO3.HCO3(water)=CO2(air)



Theglobalcarboncycleincludestheearth'satmosphere,oceans,vegeta+on,soilsandfossilfuels

• Increasedu;liza;onandburningoffossilfuel(oil,gas,coal)torunautomobiles,industry,andmachineries

• Massivedeforesta;on

• Wasteincinera;on,etc


CO2

• Type:GaseousCycle

• Majorreservoir–ATMOSPHERE

• Importance–Essen;alformanybiologicalprocesses,cons;tutespartofproteins(aminoacids),inbasesofnucleicacidsthatmakeupDNAandRNA

• 79%ofatmosphereismadeupofnitrogen(N2)butthisisINERT

• Itmustbefixedfororganismstou;lizeitDepartmentofBIOLOGY,CAS‐UPManila 43

• USEOFNITROGENFERTILIZERS– Humanuseofnitrogenfer;lizerscausesrunoff,leadingtoeutrophica;onin

aqua;csystems(e.g.eutrophica;on)

• NITRATESLEACHINGINTOGROUNDWATER– Nitrogenlevelindrinkingwaterrises– Alargeriseofnitrogenindrinkingwatersuppliesleadsto

Methemoglobinemia/Blue‐BabySyndrome

• NITROGENOXIDESRELEASEDTHROUGHCOMBUSTION– Burningoffossilfuel+automobiles:sourceofnitrogendioxide– Ozone+PANPhotochemicalSmog

• LIVESTOCKRELEASEOFLARGEAMOUNTSOFAMMONIA(FROMWASTES)

– Theammoniareleasedfromwastesoflivestockcanhavedetrimentaleffectsonfishandotherorganisms

– Thereisreduc;onindiversityDepartmentofBIOLOGY,CAS‐UPManila 44

• Type:PurelySedimental

• Majorreservoir–Earth’scrust

• Gradualcycle‐Ithasnogaseousphase– Phosphorousnormallyoccursinnatureaspartofphosphateion.– Mostphosphatesfoundassaltsinoceansedimentsorinrocks.– Over;me:geologicprocessescanbringsedimentsfromoceanto

land,andweatheringcanbringitfromlandtoocean

• Importance– Phosphorouscons;tuentofnucleicacidsinDNA,andenergy

currencyofcellATP.– Phosphorous‐alsofoundinbones,inphospholipidswhicharefound

inbiologicalmembranes.


• Humansminephosphateoresforuseinfer;lizerproduc;onanddetergents

• Humanac;onscouldleadtoeutrophica+onofaqua+csystemswhichcausealgalblooms

• AlgalbloomscausefishkillsDepartmentofBIOLOGY,CAS‐UPManila 46

• Type:Sedimentarycyclewithatmosphericcomponent

• Majorreservoir–inorganicsulfurinrocksandfossilfuel

• BiologicalImportance– Sulfurisanimportantelementinprotoplasmwhichisanimportantcomponentofsomeaminoacids.

– Sulfurispartofproteins,vitaminsandhormones


• Humansproducesulfurdioxidefromindustryandinternalcombus;onenergy

• Sulfurdioxidecanprecipitateontosurfaceswhereitcanbeoxidizedtosulfateinthesoilwhichistoxictosomeplants

• Sulfurdioxidecanbeoxidizedtosulfateinatmosphereassulfuricacidwhichisamaincons;tuentofacidrain– Acidraincanaffectchemicalbalanceoflakes.– Itacceleratesweatheringincarbonaterocks.– Leadstoforestsdamageathigheleva;ons


ns5 lecture 1 part 1

Technology

departmentofbiology

atmosphere

hco3

air

water

ons

type