Ecosystems
Ecosystem inputs
energy flows
constant
input
of energy
through
nutrients cycle
biosphere
nutrients
can only
cycle
inputs
 energy
 nutrients
Biogeochemical Cycles
• Matter is recycled and
reused between the
living and nonliving
worlds through
biogeochemical cycles
•
•
•
•
Water
Carbon
Nitrogen
Phosphorus
Water cycle
Solar energy
Transpiration
Water vapor
Evaporation
Precipitation
Oceans
Runoff
Lakes
Percolation in soil
Groundwater
Aquifer
Nitrogen cycle
Atmospheric
nitrogen
Carnivores
Herbivores
Plankton with
nitrogen-fixing
bacteria
Birds
Plants
Death, excretion, feces
Fish
excretion
Decomposing bacteria
amino acids
Ammonifying bacteria
loss to deep sediments
Nitrifying bacteria
soil nitrates
Nitrogen-fixing
bacteria
(plant roots)
Nitrogen-fixing
bacteria
(soil)
Denitrifying
bacteria
Phosphorus cycle
Plants
Land
animals
Animal tissue
Urine and feces
Soluble soil
phosphate
Decomposers
(bacteria and
fungi)
Loss in
drainage
Decomposers
(bacteria & fungi)
Phosphates
in solution
Animal tissue
and feces
Rocks and
minerals
Aquatic
animals
Plants and
algae
Precipitates
Loss to deep sediment
Carbon cycle
CO2 in
atmosphere
Combustion of fuels
Industry and home
Diffusion
Respiration
Photosynthesis
Plants
Animals
Dissolved CO2
Bicarbonates
Photosynthesis
Deposition
of dead
material
Animals
Plants and algae
Carbonates in sediment
Deposition of
dead material
Fossil fuels
(oil, gas, coal)
Carbon Cycle
•
•
•
Photosynthesis and cellular respiration form
the basis of this cycle
In photosynthesis, plants and other
autotrophs use CO2, water, and solar energy
to make carbohydrates
Autotrophs and heterotrophs break down
carbohydrates during cellular respiration
GREENHOUSE EFFECT
Breaking the water cycle
• Deforestation breaks the water cycle
– groundwater is not transpired to the
atmosphere, so precipitation is not created
forest  desert
desertification
Effects of deforestation
40% increase in runoff
loss of water
loss into
surface water
80 nitrate levels in runoff
Concentration
of nitrate (mg/l )

 60x loss in nitrogen
 10x loss in calcium
40
loss out of
ecosystem!
4
Deforestation
2
0
1965
1966
1967
Year
1968