CH12 Nitrogen, Phosphorus, and Potassium Cycle

What is the role of K (potassium) in plant function?

• Control Water Movement

• Plant enzyme activation

• Cellular growth (Cell volume and ion transport

• RESISTANCES TO DROUGHT AND SALT, PESTS AND DISEASES

• TRANSPORTING NUTRIENTS, WATER, AND SUGARS

• CONTROLS OPENING AND CLOSING OF STOMATA

What is the role of P (phosphorous)

• IMPORTANT IN DNA, ATP, and PHOSPHOLIPID MOLECULES OF CELL MEMBRANES

What is the N:P ratio in phytoplankton

N:P ratio in phytoplankton is 1:6

What is nitrification

NH4+ to NO3-

Which are reactive intermediates?

Hydroxylamine and NO2-

About what percentage of nitrogen in fuel is converted to N2?

30%

How much nitrogen does biomass burning return?

37 E 12 g N/yr

How big is the large pool of inorganic nitrogen in the deep ocean?

720E15 g N

What is the mean residence time of nitrogen in the atmosphere ?

500 million years

What is the primary mineral with significant phosphorus ?

Apatite

What are the four major steps of P cycles

1. Weathering

2. Absorption by plants

3. Absorption by animals

4. Returns to the environment through decomposition

How much potassium is mined from the earth’s crust yearly?

32.2 E 12 g K

Where is K largely found

evaporite minerals

What is K responsible for?

Osmotic and ionic balance

Electrolyte balance in blood

Contraction of muscles

Where is K normally found?

K is normally found in highest concentration in the UPPER LAYER OF SOIL

What is the C:K ratio in the human body?

484 in humans

46 in plants