2 Studying organisms in their environment biosphereecosystemcommunitypopulationorganism
3 Essential Questions What limits the production in ecosystems? How do nutrients move in the ecosystem?How does energy move through the ecosystem?
4 Ecosystem All the organisms in a community plus abiotic factors ecosystems are transformers of energy & processors of matterEcosystems are self-sustainingSunlight is needed onlycapture energytransfer energycycle nutrients
5 Ecosystem inputs nutrients cycle Inputs: energy nutrients biosphere energy flows throughconstant input of energynutrients cycleMatter cannotbe created or destroyedDon’t forget the laws of Physics!nutrients can only cycleInputs:energynutrients
6 Generalized Nutrient cycling consumersconsumersconsumersproducersdecomposersdecomposersnutrients ENTER FOOD CHAIN = made available to producersnutrients made available to producersreturn to abiotic reservoirDecomposition connects all trophic levelsabiotic reservoirabiotic reservoirgeologic processesgeologic processes
7 Carbon cycle abiotic reservoir: CO2 in atmosphere enter food chain: photosynthesis = carbon fixation in Calvin cycleRecycle:decompositionreturn to abiotic:respirationCombustion of fossil fuelsCarbon cycleCO2 inatmosphereDiffusionRespirationPhotosynthesisPlants and algaePlantsAnimalsIndustry and homeCombustion of fuelsCarbonates in sedimentBicarbonatesDeposition ofdead materialDepositionof deadmaterialFossil fuels(oil, gas, coal)Dissolved CO2
8 Nitrogen cycle Atmospheric nitrogen Carnivores Herbivores Birds Plants abiotic reservoir:N in atmosphereenter food chain:nitrogen fixation by soil & aquatic bacteriarecycle:decomposing & nitrifying bacteriareturn to abiotic:denitrifying bacteriaNitrogen cycleAtmosphericnitrogenCarnivoresHerbivoresBirdsPlankton withnitrogen-fixingbacteriaPlantsDeath, excretion, fecesFishNitrogen-fixingbacteria(plant roots)Decomposing bacteriaamino acidsexcretionAmmonifying bacteriaNitrogen-fixingbacteria(soil)loss to deep sedimentsNitrifying bacteriaDenitrifyingbacteriasoil nitrates
9 Water cycle Solar energy Transpiration Evaporation Precipitation abiotic reservoir:surface & atmospheric waterenter food chain:precipitation & plant uptakerecycle:transpirationreturn to abiotic:evaporation & runoffWater cycleSolar energyTranspirationWater vaporEvaporationPrecipitationOceansRunoffLakesPercolation in soilAquiferGroundwater
10 Ecosystem inputs nutrients cycle inputs energy nutrients biosphere energy flows throughnutrients cycleinputsenergynutrients
11 Energy flows through ecosystems sunsecondary consumers(carnivores)loss of energyloss of energyprimary consumers(herbivores)producers (plants)
12 Food chains sun Trophic levels feeding relationships Tertiary consumerTrophic levelsfeeding relationshipsstart with energy from the suncaptured by plants1st level of all food chainsfood chains usually go up only 4 or 5 levelsDue to inefficiency of energy transferall levels connect to decomposerstop carnivoreLevel 3Secondary consumercarnivoreLevel 2Primary consumerheterotrophsherbivoreLevel 1ProducerautotrophsFungiDecomposersBacteria
13 Inefficiency of energy transfer sunInefficiency of energy transferLoss of energy between levels of food chainTo where is the energy lost? The cost of living!17%growthenergy lost to daily livingonly this energy moves on to the next level in the food chain33%cellularrespiration50%waste (feces)
14 Ecological pyramid sun Loss of energy between levels of food chain can feed fewer animals in each levelFew organisms at the top due to energy loss
15 Humans 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? Vegetarians?What is your ecological footprint?!
16 Food webs Food chains are linked together into food webs Who eats whom?a species may weave intoweb at more than one levelbearshumanseating meat?eating plants?