Transcript BIOGEOCHEMICAL CYCLES

BIOGEOCHEMICAL
CYCLES
BIOGEOCHEMICAL
CYCLES
Law of conservation-atoms atoms neither created or
destroyed
Same atoms must be passed around again and again
CHNOPS make up 98% of living biomass
Biogeochemical cycles move atoms (matter, nutrients,
CHNOPS) through the air, soil, water, rocks, and living
organisms.
Recycling of atoms & flow of energy sustain life on earth
BASIC PROCESS
Producers incorporate atoms (inorganic form) from
nonliving reservoirs and convert to organic molecules
Consumers eat producers
Decomposers break down organic molecules to return
atoms (inorganic form) back to abiotic
What to look for in a cycle?
Why is nutrient important?
What are the reservoirs for the nutrient involved?
What are the driving forces that transfers nutrient from
abiotic to biotic and back to abiotic
How have humans upset the natural cycling of
particular nutrient?
Description of cycle
WATER CYCLE-Why
important
Living things are 75% water
Hydrogen in water supplies protons and electrons for
photosynthesis
Oxygen in water is released as free oxygen into air
during photosynthesis
Major solvent in living things for chemical reaction to
take place in cells and transport
Homeostasis-high specific heat
Water Cycle-Reservoirs
Ocean
Atmosphere
Glaciers
Fresh water
Ground water
Living things
Water cycle-Driving force
The sun is the major driving force of the water cycle
Causes evaporation
Causes transpiration
When cooler causes precipitation
Water cycle-Human Effect
Withdraw large amounts of water
Pollute water
Deforestation (climate change)-Loss of transpirationless water in atmosphere & increases temperature dries
out soil. Creates desert. More carbon dioxide increases
global warming.
Description of water cycle
Sun heats water in ocean
Evaporates as vapor into air
Transpiration from trees also add water vapor to
atmosphere
Cooler temperatures cause vapor to condense and
precipitate
Water returns directly to oceans as precipitation or
indirectly by runoff
Carbon Cycle-Why important?
Building blocks of cells-Proteins, Lipids,
Carbohydrates, Nucleic acids are carbon based
molecules
Carbon and oxygen from carbon dioxide is used to
make glucose in photosynthesis
Carbon cycle reservoirs
Atmosphere in the form of inorganic carbon dioxide
Carbon dioxide dissolved in oceans
Living things in form of organic molecules
Underground-fossil fuels
Rocks-limestone (calcium carbonate)
Carbon cycle driving force
Photosynthesis captures inorganic carbon in form of
carbon dioxide and converts it to organic molecules
(glucose)
Cell respiration returns carbon dioxide to abiotic
Carbon cycle-Human effect
Humans are adding excess carbon dioxide to
atmosphere through burning of fossil fuels and
deforestation (loss of carbon dioxide removal)
Carbon cycle description
Carbon dioxide is captured by plants and converted into
organic molecules by photosynthesis
Consumers eat plant and carbon ids transferred
Organism die and decomposers break organic molecules
back to carbon dioxide and released back to air
Cell respiration also returns carbon dioxide back to air.
Burning fossil fuels & volcanoes increase carbon dioxide in
air
Nitrogen Cycle-Why important
Important in making nucleic acids, ATP, and Amino
acids
Nitrogen Cycle-Reservoir
Atmosphere is 75% free nitrogen
Nitrogen Cycle driving force
Bacteria
Nitrogen fixing bacteria capture free nitrogen from air and
convert it to ammonia
Nitrifying bacteria-convert ammonium to nitrates and
nitrites
Denitrifying bacteria convert nitritrites back to free nitrogen
Ammonifying bacteria convert organic molecules to
ammonium
Nitrogen Cycle-human effect
Fertilizers contain large amounts of nitrogen-run off in
stream create eutrophication
Nitrogen released into air by factories combine with
water to form nitric acid-acid rain
Farming depletes soil of nitrogen
Nitrogen cycle description
Free atmospheric nitrogen is converted by nitrogen fixing
bacteria found in soil and root nodules of legumes to
ammonia
Plants can use ammonia but ammonia is usually converted
to nitrates and nitrites by nitrifying bacteria which plants
take up
Consumers eat plants
Organisms die and ammonifying bacteria convert back to
ammonia which can be nitrified and reused or denitrified by
denitrifying bacteria to free nitrogen again.
Create your own slides for the phosphorus cycle