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2 basic laws underlie ecosystem function
nutrients constantly cycle and recycle
Energy moves through ecological communities in a continuous one way flow and doesnt go back to the sun
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trophic level
each category of organisms
- producers= autotrophs
- consumers- heterotrophs
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primary consumers
herbivores
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secondary consumers
carnivores
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net primary production
the energy stored in producers
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net primary production is influenced by the amount of
- Nutrients available to producers
- The amount of sunlight reaching them
- The appropriate amouts of water and temperature
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detritus feeders
live on dead organic matter, including the bodies of other organisms, fallen leaves and fruit, and wastes (vulchures)
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biomass
the weight of living material at each trophic level
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Nutrient cycles
pathways nutrients follow between communities and the nonliving portions of ecosystems.
nitrogen, carbon, phosphorous, hydrolic cycles
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The carbon cycle
movement of carbon from its major short term reservoirs through producers, into the bodies of consumers and detritus feeders, and then backto its reservoirs
Get it back form respiration, photosynthesis, and decomposition
Interfering with this cycle is warming the earth's climate
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the nitrogen cycle
nitrogen moves from nitrogen gas in the atmosphere (78? of air in atmosphere)
to reservoirs of ammonia and nitrate in the soil and water, through producers and into consumers and detritus feeders, and then back again to its reservoirs
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nitrogen is a crucial compoment of
protients, many vitamins, nucleotides (ATP) and nucleic acids
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nitrogen fixation
- bacteria convert the ammonia into nitrate that plants can directly use
- Others live in symbiotic associations with plants called legumes, which include alfalfa, soybeans, clover, and peas
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the phosphorus cycle
its major reservoir in rock bound to oxygen as phosphate
- ATP and NADP, nucleic acids, and major component of vertebrate teeth and bones
- Main source- rocks
- Replenished from geological uplift- rocks rising- glaciers melting, washing up from ocean, ect
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greenhouse gasses
- CO2, methane, nitrous oxide
- trap the heat in the atmosphere
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global warming process
- 1. sunlight energy enters the atmosphere
- 2. some energy is reflected back into space
- 3. most sunlight strikes the Earth's surface and is converted into heat
- 4. Heat is radiated back into atmosphere
- 5. Most heat is radiated back into space
- 6. Some atmospheric heat is retained by greenhouse gases
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Effects of global warming
- 1. Rising sea levels will flood many coastal cities and wetlands and may increase hurricane intensity.
- 2. More extreme weather patterns
- 3.Will alter air and water currents- changing precipitation patterns
- 4. Forests may suffer loss of species or be repleaced by grasslands
- 5. Coral reefs may decline due to warming waters
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