Biogeochemical Cycles Flashcards
Water Cycle
1) rain precipitates water onto Earth
2) Water lands into the oceans. It also lands on soil, and runs-off into the oceans after used by living things.
3) Water from the ocean evaporates into the air.
4) Water in the air condenses into clouds.
3-4: Water moving through a plant is called Transpiration. When water evaporates off a plant, it is called evapotranspiration.
Solid - Liquid
+Heat energy
“melting”
Liquid - Gas
-Heat energy
“evaporation”
Liquid - Water Vapor
+Heat energy
“evaporation”
Water vapor - Liquid
-Heat energy
“condensation”
Soild - Water Vapor
“sublimation”
Water Vapor - Solid
“deposition”
Water cycle (image)
1) Condensed water vapor
2) Advection (movement of clouds over land)
3) Precipitation: rain, hail, snow, sleet, graupel
4) Run off or infiltration - ground water (percolation) - settles there.
5) Ocean
6) Evaporation
or
4) Evapotranspiration: water evaporates off of leaves
or
4) Transpiration: Plant sucks up H2O from roots.
Carbon cycle
- producers convert inorganic carbon dioxide into organic molecules.
- Consumers eat the producers.
- Consumers breath out CO2 which is reused by the autotrophs.
- ## *Since photosynthesis generate oxygen, the oxygen cycle is coupled witht he carbon cycle.
Cabrbon sink
where carbon is stored (a reservoir)
How it is labeled
Flow (process) annotated with an arrow
a) transformed from a->b (solid -> liquid)
Storage (reservoir, reserve, store) annotated with a box.
Two carbon cycles
- inorganic (combustion: burning, fossil fuels)
- Organic
Photosynthesis (H2O + CO2) –> Cellular Respiration (C6H12O6 (Glucose sugar)+O2+ATP (energy))
Carbon cycle reflects
the connected processes of photosynthesis and cellular respiration
Carbon stored
1) deep ocean
2) atmosphere
3) plants (esp. forests)
4) soils
Nitrogen cycle
Nitrogen fixin bacteria
- send into soil as ammonia (NH3)
Runs into Nitrogen fixing soil bacteria
- turns it into ammonium (NH+4)
Nitrifying bacteria
- converts it into nitrates (NO-3)
Nitrifying bacteria
- converts into nitrites (NO-2)
or
Animal eat it (then excrete or die)
- denitrifying bacteria (enzyme: Nitrate Reductase)
Converts into N2 (goes back into the atmosphere)
Legume
-peanuts
-soy
-klover
-kudzo
Important reason for Nitrogen
- make amino acids which code for protein
plants can absorb
ammonia NH3
ammonium NH+4
Nitrates NO-3
Nitrites NO-2
where to find nitrogen
In RNA and DNA
Phosphorus Cycle
1) Phosphorus from rocks leaks into the soil by the sediment run-off.
2) Phosphorus is added to the soil as phosphate.
3) Plants absorb the phosphate.
4) Animals eat the plants.
5) Consumers excrete feces or decomposers break down the wastes, which drains by run-off to the oceans.
6) The coeans deposit the phosphorus onto rocks.
Theme of phosphorus cycle
rocks and poo
Element of phosphorus
P
Organic form of phosphorus
phosphate
Where is phosphate found in cells?
1) DNA + RNA
2) ATP: adenosinetriphosphate
3) Cell membrane: phospholipid bilayer
Phosphorus cycle is the only cycle that
does not pass through the atmosphere
Organic Phosphorus Cycle
1) weathering
2) erosion
3) sediments
4) deposition
- phosphate -> compacted -> cemented
5) new sedimentary rock
6) geological uplift
7) metamorphic rock
or
5) eats plants -> dies (100,000 years - becomes a rock) or poops (back into soil)
2 phosphorus cycles
Organic (100,000 years) + Inorganic (millions of years)
percentage
oxygen: 65%
carbon: 18.5%
hydrogen: 9.5%
nitrogen: 3.3%
phosphorus: 1%
Biogeochemical cycle
pathways for molecules like H2O or elements like C, N and P to move through all the Earths various ecological and geological compartments
Reservoir
Where water is stored
Precipitation
water falling to the earth by gravity
Condensation
when H2O vapor cools and forms clouds (floating reservoir)
Run-off
H2O moving to the lowest point by gravity (over the surface of the land).
Ocean is salty
As water runs to the ocean, it erodes minerals like salt (NCl) from soil and it carries it to the ocean.
3 ways human body loses water
1) sweating
2) breathing
3) peeing
Evapotranspiration
When H2O evaporates off the leaves of plants
Plants involved in the Carbon Cycle
They absorb CO2 (they are storage for Carbon) - photosynthesis
1) some CO2 is released through cellular respiration.
2) Carbon in plants returns to soil in death.
what are shells made of? what happens when they fall to the bottom of the ocean?
made of calcium carbonate (CaCO3)
when they fall they compact and cememt into rock over a long period of time.
What happens to limestone when it dissolves in water?
it breaks down and releases CO2 and carbonic acid (H2CO3)
What happens to carbon in the ocnean?
absorbed by phytoplankton
ocean absorbs 33% of the CO2 in the atmosphere
it usually sinks to the bottom to build rock over time.
What is happening with excess Carbon in thw astmosphere?
Its creating a greenhouse gas effect
too much CO2 in the atmosphere warms the planet too much and too fast.
What is a positive feed back loop?
Permafrost melts
CO2 is released
greenhouse effect worsens
planet warms
more melt.
negative
What do we need nitrogen to make?
Amino acids –> proteins
What do we need phosphorus to make?
ATP, DNA + RNA, Phospholipid bilayer (cell membrane)
What percentage of the atmosphere is nitrogen?
78% in the form of N2 (diatomic molecule and a gas)
What is the chemical formula for Nitrate
NO-3
What is the chemical formula for nitrite
NO-2
What is the chemical formula for ammonium
NH+4
what is nitrogen fixation?
Breaking the triple covalent bond to make nitrogen usable for plants.
What are nitrogen fixing bacteria?
these are specialized bacteria that can fix nitrogen
What plans are in the legumes family? What does it mean that they have a symbiotic relationship?
soybeans, clovers, peanuts, kudzo
means it is mutually beneficial
What form of nitrogen is usable by plants? What enzyme makes it useful?
ammonium, nitrates and nitrites
nitrogenase - a specialized enzyme
What does Nitrifying bateria do?
takes ammonia and converts it into nitrates
What other things can break nitrogen molecules a part?
lightening and synthetic fertilizers
What is special about the phosphorus cycle?
Only cycle that is not passed through the atmosphere.
What is denitirfying bacteria? which enzyme does this?
Turn organic nitrogen back into nitrogen gas. Enzyme: Nitrate Reductase
What is the lithosphere
earths crust
What rock is rich in phosphorus?
Sedimentary rock
How do phosphates end up in water?
Through weathering, erosion and deposition
What is lithotroph?
rock-eating bacteria
How do phosphates end up in soil?
phosphates in water can get absorbed in the soil.
How long can a single phosphorus atom get trapped in a cycle for?
100,000 years in a biological cycle
millions of years in an inorganic
What are the main ingredients in fertilizers
Nitrogen and phosphorus (nitrates and phosphates)
Why is too much nitrogen and phosphorus bad for the environment?
Excess N and P polute water leading to algae bloom (gathers at the top of the ocean, suffocating the sealife below)
Partitioning
relating to the cycling of chemical elements and compounds between living organisms, the atmosphere, and the Earth’s crust.
Leaching
the act of dividing or distributing something into parts or sections.
Induced
caused or brought about by someone or something
Deforestation
the clearing or removal of forests or trees from an area
Facets
distinctive aspects or features of something
Photosynthesis
the process by which green plants and some other organisms use sunlight ot synthesize foods with the help of chlorophyll.
Decomposition
the process by which organic substances are broken down into simpler forms of matter, resulting in the release of nutrients back into the environment.
Sustainability
the ability to be maintained at a certain rate or level without depleting resources or causing harm to the environment.
How are human activities related to biogeochemical cycles?
Burning fossil fuels
- Releases extra carbon dioxide (CO₂) into the air.
- Contributes to climate change and global warming.
Using chemical fertilizers
- Adds nitrogen and phosphorus to soil and water.
- Can cause water pollution and harmful algae blooms.
Deforestation
- Reduces the number of trees that absorb CO₂.
- Disrupts the carbon and water cycles by changing how nutrients and water move
What role do soils play in beigeochemical cycles?
Nutrient storage and recycling
- Soil holds key nutrients like nitrogen, phosphorus, and potassium.
Supports decomposers
- Microbes and fungi break down dead matter → return nutrients to the soil.
Carbon storage
- Soil stores organic carbon (from plant and animal remains).
Water filtering
- Helps clean water as it moves through the ground.
How do biogeochemical cycles contribute to the availability of essential elements to plants and other organisms?
Elements cycle through ecosystems
- Like a natural recycling system for carbon, nitrogen, phosphorus, etc.
Plants absorb nutrients
- From soil or water (e.g., nitrates, phosphates, CO₂).
Animals get nutrients
- By eating plants or other animals.
Decomposition returns elements
- Dead organisms break down → nutrients go back to soil/water.
What are some human activities that can disrupt biogeochemical cycles?
Fertilizer overuse
- Excess nutrients run off into lakes and rivers → eutrophication (too much algae).
Burning fossil fuels
- Adds too much CO₂ → climate change.
Deforestation and land clearing
- Reduces natural nutrient flow and increases soil erosion.
Waste pollution
- Adds harmful chemicals and disrupts natural cycles.
What happens to carbon dioxide in the carbon cycle?
Absorbed by plants
- During photosynthesis, plants use CO₂ to make food.
Released by animals
- Through respiration (breathing out CO₂).
Goes into oceans
- Oceans absorb some CO₂ → helps balance the atmosphere.
Released by decay and burning
- Decomposing organisms or burned materials release CO₂.
How does nitrogen cycle convert atmospheric nitrogeb gas into usable forms?
Nitrogen fixation
- Bacteria in soil or plant roots change N₂ gas into ammonia (NH₃).
Nitrification
- Other bacteria convert ammonia into nitrates (NO₃⁻) plants can use.
Assimilation
- Plants take in nitrates → animals eat plants → nitrogen enters food chain.
Denitrification
- Some bacteria turn nitrates back into N₂ gas, returning it to the atmosphere.
Why is it important to implement best practices in soil management?
Supports plant growth
- Healthy soil has nutrients, air, and water plants need.
Prevents erosion
- Good practices (like planting cover crops) keep soil in place.
Reduces pollution
- Avoiding excess fertilizer prevents runoff into water systems.
Stores carbon
- Healthy soil locks away carbon, helping to reduce climate change effects.
Biogeochemical
relating to the cycling of chemical elements and compounds between living organisms, the atmosohere, and the Earth’s crust.
