PowerPoint Presentation

Ecosystems1biosphere

ecosystemcommunitypopulationStudying organisms in their environmentorganism2Essential questionsWhat limits the production in ecosystems?How do nutrients move in the ecosystem?How does energy move through the ecosystem?

3EcosystemAll the organisms in a community plus abiotic factorsecosystems are transformers of energy & processors of matterEcosystems are self-sustainingwhat is needed?

capture energytransfer energycycle nutrients4biosphere

Ecosystem inputsconstant inputof energyenergy flowsthroughnutrients cyclenutrients can only cycleinputsenergynutrients

Dont forgetthe laws of Physics! Matter cannotbe created ordestroyed 5

consumersdecomposersabioticreservoirnutrientsmade availableto producersgeologicprocessesGeneralized Nutrient cyclingconsumersconsumersproducersdecomposersabioticreservoirnutrientsENTER FOOD CHAIN= made availableto producersgeologicprocessesDecompositionconnects all trophic levelsreturn toabioticreservoir6Carbon cycle

CO2 inatmosphereDiffusionRespirationPhotosynthesisPhotosynthesisPlants and algaePlantsAnimalsIndustry and homeCombustion of fuelsAnimalsCarbonates in sedimentBicarbonatesDeposition ofdead materialDepositionof deadmaterialFossil fuels(oil, gas, coal)Dissolved CO2abiotic reservoir:CO2 in atmosphereenter food chain:photosynthesis = carbon fixation in Calvin cyclerecycle: return to abiotic:respirationcombustion

BirdsHerbivoresPlantsamino acidsCarnivoresAtmosphericnitrogenloss to deep sedimentsFishPlankton withnitrogen-fixingbacteriaNitrogen-fixingbacteria(plant roots)Nitrogen-fixingbacteria (soil)DenitrifyingbacteriaDeath, excretion, fecesNitrifying bacteriasoil nitratesexcretionDecomposing bacteriaAmmonifying bacteriaNitrogen cycleabiotic reservoir:N in atmosphereenter food chain:nitrogen fixation by soil & aquatic bacteriarecycle:decomposing & nitrifying bacteriareturn to abiotic:denitrifying bacteria

Phosphorus cycle

Loss to deep sedimentRocks andmineralsSoluble soilphosphatePlants andalgaePlants UrineLand animalsPrecipitatesAquaticanimalsAnimal tissueand fecesAnimal tissueand fecesDecomposers(bacteria andfungi)Decomposers(bacteria & fungi)Phosphatesin solutionLoss indrainageabiotic reservoir:rocks, minerals, soilenter food chain:erosion releases soluble phosphateuptake by plantsrecycle:decomposing bacteria & fungireturn to abiotic:loss to ocean sediment

LakesRunoffPercolation in soilEvaporationTranspirationPrecipitationOceansSolar energyAquiferGroundwaterWater cycleWater vaporabiotic reservoir:surface & atmospheric waterenter food chain:precipitation & plant uptakerecycle:transpirationreturn to abiotic:evaporation & runoff

Transpiration

Remembertranspiration?

Breaking the water cycleDeforestation breaks the water cyclegroundwater is not transpired to the atmosphere, so precipitation is not created

forest desert desertification

Effects of deforestation

Concentration of nitrate (mg/l )19651966Year204408019671968Deforestationnitrate levels in runoff40% increase in runoffloss of water60x loss in nitrogen10x loss in calciumloss into surface waterloss out of ecosystem!

Why isnitrogen soimportant? biosphere

Ecosystem inputsenergy flowsthroughnutrients cycleinputsenergynutrients14Energy flows through ecosystemssunproducers (plants)loss of energyloss of energysecondary consumers(carnivores)primary consumers(herbivores)15Food chainsTrophic levelsfeeding relationshipsstart with energy from the sun captured by plants1st level of all food chainsfood chains usually go up only 4 or 5 levelsinefficiency of energy transferall levels connect to decomposers

FungiLevel 4Level 3Level 2Level 1DecomposersProducerPrimary consumerSecondary consumerTertiary consumertop carnivorecarnivoreherbivoreBacteriaautotrophsheterotrophssun16

Inefficiency of energy transferLoss of energy between levels of food chainTo where is the energy lost? The cost of living!only this energymoves on to the next level in the food chain17%growth50%waste (feces)33%cellularrespirationenergy lost todaily livingenergy lost todaily livingsun17Ecological pyramidLoss of energy between levels of food chaincan feed fewer animals in each level

1,000,000,000100,0001001sun18Humans in food chainsDynamics of energy through ecosystems have important implications for human populationshow much energy does it take to feed a human?if we are meat eaters?if we are vegetarian?

What is yourecological footprint?! 19Food websFood chains are linked together into food websWho eats whom?a species may weave into web at more than one levelbearshumanseating meat?eating plants?

202006-2007

Any Questions??Were workingon a lotof them!21