Studying organisms in their environment biosphere ecosystem community population organism 2

Essential questions What limits the production in ecosystems? How do nutrients move in the ecosystem? How does energy move through the ecosystem? 3

Ecosystem All the organisms in a community plus abiotic factors Transform energy & process matter Ecosystems are self-sustaining what is needed? capture energy transfer energy cycle nutrients 4

Ecosystem inputs nutrients cycle inputs energy nutrients biosphere energy flows through constant input of energy nutrients cycle Matter cannot be created or destroyed Don’t forget the laws of Physics! Nutrients cycle inputs energy nutrients 5

Generalized Nutrient cycling consumers decomposers abiotic reservoir nutrients made available to producers geologic processes producers nutrients ENTER FOOD CHAIN = made available to producers return to abiotic reservoir Decomposition connects all trophic levels 6

Water cycle Solar energy Transpiration Evaporation Precipitation abiotic reservoir: surface & atmospheric water enter food chain: precipitation & plant uptake recycle: transpiration return to abiotic: evaporation & runoff Water cycle Solar energy Transpiration Water vapor Evaporation Precipitation Oceans Runoff Lakes Percolation in soil Aquifer Groundwater

Breaking the water cycle Deforestation breaks the water cycle groundwater is not transpired. Precipitation is not created. forest  desert desertification

Repairing the damage The Greenbelt Movement planting trees in Kenya restoring a sustainable ecosystem establishing democracy empowering women Wangari Maathai Nobel Peace prize 2004

Nitrogen cycle Atmospheric nitrogen Carnivores Herbivores Birds Plants abiotic reservoir: N in atmosphere enter food chain: nitrogen fixation by soil & aquatic bacteria recycle: decomposing & nitrifying bacteria return to abiotic: denitrifying bacteria Atmospheric nitrogen Carnivores Herbivores Birds Plankton with nitrogen-fixing bacteria Plants Death, excretion, feces Fish Nitrogen-fixing bacteria (plant roots) Decomposing bacteria amino acids excretion Ammonifying bacteria Nitrogen-fixing bacteria (soil) loss to deep sediments Nitrifying bacteria Denitrifying bacteria soil nitrates

Phosphorus cycle abiotic reservoir: rocks, minerals, soil enter food chain: erosion releases soluble phosphate uptake by plants recycle: decomposing bacteria & fungi return to abiotic: loss to ocean sediment Land animals Plants Animal tissue and feces Urine Soluble soil phosphate Decomposers (bacteria and fungi) Loss in drainage Rocks and minerals Phosphates in solution Decomposers (bacteria & fungi) Animal tissue and feces Aquatic animals Plants and algae Precipitates Loss to deep sediment

Carbon cycle abiotic reservoir: CO2 in atmosphere enter food chain: photosynthesis = carbon fixation in Calvin cycle recycle: decomposition return to abiotic: respiration combustion Carbon cycle CO2 in atmosphere Diffusion Respiration Photosynthesis Plants and algae Plants Animals Industry and home Combustion of fuels Carbonates in sediment Bicarbonates Deposition of dead material Deposition of dead material Fossil fuels (oil, gas, coal) Dissolved CO2

Carbon Cycle Most of the carbon on earth is locked up in the crust in limestone rocks: CaCO3

Some of the rest is in fossil fuels: coal, crude oil and natural gas. Coal = carbon Methane = CH4

Some is in the atmosphere as CO2

A lot is dissolved in seawater as carbonate (CO32-), bicarbonate (HCO3-), carbonic acid (H2CO3) and carbon dioxide (CO2)

And of course some is in living & dead biological tissue (Biomass)

PHOTOSYNTHESIS (plants and Algae): 6CO2 + 6H2O  C6H12O6 + 6O2 (sunlight) RESPIRATION (all life) C6H12O6 + 6O2  6CO2 + 6H2O (+ energy!) Where: C6H12O6 = sugar O2 = oxygen CO2 = carbon dioxide H2O = water

Carbon Cycle getting started… Respiration: Sugar + O2  CO2 + H2O CO2 + H2O  sugar + O2 Photosynthesis: CO2 Limestone CaCO3 CO2

The main thing is to present it as a CYCLE That means every place with carbon has at least one arrow coming in and one arrow going out!