Nutrient Fluxes

1
Nutrient Fluxes Starring Carbon, Nitrogen, and
Phosphorous
2
Whats a nutrient? An element essential for an
organisms maintenance and growth that must be
obtained from the environment or by consumption
of other organisms
3
Carbon cycle active compartments 1.
Photosynthesisremoves C from cycle (
sink) 2. Respirationadds C to cycle (
source) Before industrialization, source sink
4
Carbon balance in oceans
CaCO3 H2O CO2 Ca 2HCO3-
Insoluble form of carbon
Soluble form of carbon
Photosynthesis removes CO2, drives reaction to
the left calcium carbonate drops outs of
solution and carbon enters storage poolis taken
out of active carbon cycle
5
Phosphorous cycle
Primary source the earths crust, particularly
under the oceans P the limiting nutrient in
freshwater systems, particularly lakes
6
Nitrogen cycle Original source atmosphere N
the limiting nutrient in terrestrial
ecosystems, oceans Primary input to
biosphere before industrialization N-fixation
by lightning, bacteria
7
Azolla water fern with symbiotic, N-fixing
cyanobacteria
W/o cyanobacteria With cyanobacteria
8
Bush lupine N-fixing shrub native to northern CA
Now invasive in dune communities elsewhere in CA
9
Myrica vs. native plants of Hawaii
Ohia native
Myrica alien aggressor

• Myrica introduced in late 1800s as ornamental or
  medicinal plant
• Invades low-N habitats, such as lava beds
• Displaces native species, such as Ohia

10
Effect of nitrogen fertilizer on
species diversity in a Minnesota grassland
Control plotno fertilizer
Plot with N-fertilization
11
Nutrient fluxes the end
By the people who brought you paper plates,
paper toilet seat liners, paper bathing suits,
paper hospital gowns, paper diapers . . .