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Ecosystems. Studying organisms in their environment. biosphere. ecosystem. community. population. organism. Essential questions. What limits the production in ecosystems? How do nutrients move in the ecosystem? How does energy move through the ecosystem?. Ecosystem.
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Studying organisms in their environment biosphere ecosystem community population organism
Essential questions • What limits the production in ecosystems? • How do nutrients move in the ecosystem? • How does energy move through the ecosystem?
Ecosystem • All the organisms in a community plus abiotic factors • ecosystems are transformers of energy& processors of matter • Ecosystems are self-sustaining • what is needed? • capture energy • transfer energy • cycle nutrients
Ecosystem inputs biosphere constant inputof energy energy flowsthrough nutrients cycle nutrients can only cycle inputs • energy • nutrients
Decompositionconnects all trophic levels Generalized Nutrient cycling consumers consumers producers consumers decomposers decomposers nutrientsmade availableto producers nutrientsmade availableto producers abioticreservoir abioticreservoir geologicprocesses geologicprocesses
CO2 in atmosphere Combustion of fuels Industry and home Photosynthesis Diffusion Respiration Plants Animals Dissolved CO2 Bicarbonates Photosynthesis Deposition of dead material Animals Plants and algae Fossil fuels (oil, gas, coal) Deposition of dead material Carbonates in sediment Carbon cycle
Nitrogen cycle Atmospheric nitrogen Carnivores Herbivores Birds Plants Plankton with nitrogen-fixing bacteria Death, excretion, feces Nitrogen-fixing bacteria (plant roots) Fish Decomposing bacteria amino acids excretion Nitrogen-fixing bacteria (soil) Ammonifying bacteria loss to deep sediments Nitrifying bacteria Denitrifying bacteria soil nitrates
Phosphorus cycle 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 Plants and algae Aquatic animals Precipitates Loss to deep sediment
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 to the atmosphere, so precipitation is not created forest desert desertification
Wangari Maathai Repairing the damage • The Greenbelt Movement • planting trees in Kenya • restoring a sustainable ecosystem • establishing democracy • empowering women Nobel Peace prize 2004
7800 acres Studying ecosystems 38 acre deforestation Hubbard Brook Experimental Forest
Effects of deforestation 40% increase in runoff • loss of water • 60x loss in nitrogen • 10x loss in calcium loss into surface water nitrate levels in runoff 80 40 loss out of ecosystem! Concentration of nitrate (mg/l ) 4 Deforestation 2 0 1965 1966 1967 1968 Year
Ecosystem inputs biosphere energy flowsthrough nutrients cycle inputs • energy • nutrients
loss of energy loss of energy Energy flows through ecosystems sun secondary consumers (carnivores) primary consumers (herbivores) producers (plants)
sun Level 4 Tertiary consumer Food chains • Trophic levels • feeding relationships • start with energy from the sun • captured byplants • 1st level of all food chains • food chains usually go up only 4 or 5 levels • inefficiency of energy transfer • all levels connect to decomposers top carnivore Level 3 Secondary consumer carnivore Level 2 Primary consumer heterotrophs herbivore Level 1 Producer autotrophs Fungi Decomposers Bacteria
sun energy lost todaily living energy lost todaily living Inefficiency of energy transfer • Loss of energy between levels of food chain • To where is the energy lost? The cost of living! 17% growth only this energymoves on to the next level in the food chain 33% cellular respiration 50% waste (feces)
sun Ecological pyramid • Loss of energy between levels of food chain • can feed fewer animals in each level Numbers 1 100 100,000 1,000,000,000
Humans in food chains • Dynamics of energy through ecosystems have important implications for human populations • how much energy does it take to feed a human? • if we are meat eaters? • if we are vegetarian? What is yourecological footprint?!
Food webs • Food chains are linked together into food webs • Who eats whom? • a species may weave into web at more than one level • bears • humans • eating meat? • eating plants?