3.4- Cycles of Matter Flashcards
Unlike to one-way flow of energy- matter is:
recycled within and between ecosystems
What are biogeochemical cycles?
closed loops in which elements pass from one organism to another and among parts of the biosphere
What are biogeochemical cycles powered by?
the flow of energy
Cycles of matter involve:
biological, geological and chemical processes, human activity
As matter is moved through the cycles:
it is transformed- never created or destroyed only changed
Biological processes:
all activites perfomed by living organisms
Ex: eating, breathing, burning food, elimating waste products
Geological processes:
volcanic eruptions, formation and breakdown of rock, major movements of matter within and below the surface of the earth
Chemical and Physical processes:
formation of clouds, precipitation, flow of running water, the action of lightning
Human activity:
things that effect cycles of matter on a global scale:
mining and burning of fossil fuels, clearing of land for building/farming, burning of forests, manufacture and use of fertilizers
Biological, geological, chemical, physical, processes and human activity pass the same atoms/molecules:
around again and again the biosphere (never ending cycle)
Example of the cycle of matter for an atom:
carbon atom in CO2 that has came up from a volcane, blueberryp lant absorbes that carbom atom during photosynthesis, caribou eats the blueberry, then carbon atom passes out the caribou, swallwd by dung bettle whoch is eaten by shrew, carbon atom is combined in its tissue, then eated by owl, and gets released by in atmosphere when it exhales finally dissolve in a drop of rain water and flow through the river into the ocean
In the water cycle:
water continuously moves between the oceans, atmosphere, land and sometimes outside and inside living things
Water Cycle 1st step:
water from oceans/lakes evaporates and condenses into clouds
physical/chemical
Water Cycle 2nd step:
water falled to surface as precipitation; surface runoff leads through rives to lakes nad oceans, some water seeps into the ground becoming groundwater
physical/chemical
Water cycle 3rd step:
groundwater taken up by plant roots is released into the atmosphere through transpiration
biological
What are nutrients?
chemical substances that an organism needs to sustain life
Why do organisms need nutrients?
to build tissue and carry out life functons
How do nutrients pass through organisms and the envirnoment?
through biogeochemical cycles
What are the 3 critical nutrient cycles?
carbon, nitrogen, phosphorus
How does oxygen cycle through the biosphere?
oxygen combines with the elements and cycles with them; repiration and photosynthesis also contribute
What is calcium carbonate important for?
skeletons and found in rocks (CaCO3)
What is carbon dioxide important for?
important part of atmosphere and is dissolved in oceans
What are fossil fuels?
coal, oil, natural gas; fossilized carbon, ancient forests, marine organisms containing carbon have been buried and transformed into fossil fuels
Where are resources of carbon in the biosphere?
atmosphere, oceans, rocks, fossil fuels, forests
Describe the carbon cycle:
Why do all organisms need nitrogen?
to make amino acids
Nitrogen gas (N2) is how much of the atmosphere?
78%
Where is nitrogen found?
ammonia, nitrate ions, nitrite ions is soil, waste of organisms, dead/decaying matter
What is nitrogen fixation?
only some bacteria can use N2 directly, so they convert nitrogen gas into ammonia
other bacteria convert fixed nitrogen into nitrates and nitrites
What is denitrification?
some bacteria obtain energy by converting nitrates into nitrogen gas which is releaseed into atmosphere in this process
Describe the nitrogen cycle:
Why is phosphorus important?
part of DNA and RNA, but not abundant in biosphere
How is phosphorus cycled?
does not enter in atmosphere, but in inorganic phosphate on land
Describe the phosphate cycle:
If ample sunlight and water are avaliable:
the primary productivity (rate at which primary producers create organic material), of an ecosystem may be limited by the avaiability of nutrients
What is a limiting nutrient?
the nutrient whose supply limits productivity
even a single essential nutrient that is in short supply can limit primary productivity
What is the purpose of fertilizer?
growth of crops typically limited by one or more nutrients that must be taken up by plants through roots
How is fertilizer made up?
contain large amounts of nitrogen, phosphorus, potassium; micronutrients (small amounts) of calcium, magnisium, sulfur, iron
What are the limiting nutrients of seawater and freshwater?
seawaer: nitrogen
Freshwater: phosphorus
What causes algae bloom?
heavy rain/runoff from fertilized feilds input large amount of limiting nutrient
