Element Cycles

EQ: How can I explain the difference between nitrogen fixation and denitrification.

BIOGEOCHEMICAL CYCLES

Matter within ecosystems is

recycled.

decomposersbacteria and fungi

soilminerals and

humus

producersgreen algae

water and salts

consumersanimals

decay

dieeaten

die

All Cycles Are Related

Carbon, Nitrogen, Sulfur, Phosphorusin

Plants and Organisms

N2

Fossil Fuel Combustion

H2O

CO2

SO2, NO2

Phyto- plankton

Zoo- plankton

Ocean Sediments

Nutrient Recycling

Nitrogen Fixing Bacteria

Nitrates, Sulfates,

Phosphates

Phosphate

Nitrite, Dead Organic Mattrer &

Decomposers

H2O

Urea Runoff

Respiration Decomposition

Transpiration

BIOGEOCHEMICAL CYCLES• Water, carbon, oxygen,

nitrogen & other elements cycle from the abiotic to biotic & then back to the environment.

bioticabiotic

BIOGEOCHEMICAL CYCLES

• Three example cycles:

• Water

• Carbon (carbon-oxygen)

• NitrogenH2O C

N O

NITROGEN CYCLE• 79% of the atmosphere is

nitrogen gas but it is in a form most living things cannot use.

N2free

nitrogen

NITROGEN CYCLE

• If we can’t take in free nitrogen, how do we acquire it so we can use it in our bodies?

• Why do we need nitrogen in our bodies?

NITROGEN CYCLE

• Nitrogen-fixing bacteria convert NITROGEN into NITRATES.

• Plants absorb NITRATES.

• Animals eat plants.

N2

in airnitrogen-fixing

bacteria

NITRATES

NITROGEN CYCLE• How does the nitrogen return to

the atmosphere?• Denitrifying bacteria convert

the nitrates back into nitrogen.

N2

in airnitrogen-fixing

bacteria

NITRATES

denitrifyingbacteria

NITROGEN CYCLE• Why do we need nitrogen?

• Nitrogen is an essential element for all proteins (amino acids) and nucleic acids.

NITROGEN CYCLE

Can plants & animals use free nitrogen?

In what form must N2 be to be used by plants?

What organisms can fix the N2 into a usable form?

N2free

nitrogen

nitrates

nitrogen-fixingbacteria

NITROGEN CYCLE

nitrogen-fixing bacteria

nitratesorganicmatter

denitrifyingbacteria

gaseous losses (N2, NOx) lightning

fixes N2 intonitrates

CLOCK BUDDY TIME

3:00 CLOCK BUDDY

Draw and explain the nitrogen cycle, highlighting nitrogen fixation and denitrification.

CARBON CYCLE• The exchange of gases during

photosynthesis and respiration is a major example of the living-nonliving cycle of carbon-oxygen.

respirationphotosynthesis

O2

CO2

CARBON CYCLE

• How does carbon enter the living part of the cycle?

CO2 + H2O ----> C6H12O6 + O2

CO2CO2

CO2

CO2 CO2

CO2

CO2CO2

Using the process of PHOTOSYNTHESIS, plants use CO2 to make food

CARBON CYCLE

• Carbon is returned to the atmosphere environment by: (leave space to write the definition)

• cellular respiration

• erosion

• combustion

• decomposition

CARBON CYCLE

limestone

combustion

soil erosion

animal respiration

plant respiration

photosynthesisby plants

photosynthesisby algae

respirationby algae

and aquaticanimals

litter

fossil fuelscoal, gas, petroleum

CO2 in Atmosphere

decomposition oceans, lakes

RESPIRATION - CO2 is released back into the atmosphere when food (glucose) is broken down during respiration

PHOTOSYNTHESIS - Plants use carbon dioxide to make food

DECOMPOSITION - CO2 is released back into the atmosphere as organic matter is broken downCOMBUSTION - CO2 is released

back into the atmosphere when organic material is burned EROSION - CO2 is released back

into the atmosphere when erosion breaks down certain rock

decomposition