1.6 phosphorus cycle

Phosphorus cycle

Movement of phosphorus atoms and molecules between sources and sinks/reservoirs

Major reservoirs

Rocks and sediments containing phosphorus minerals

Phosphorus cycle is very___

Slow compared to carbon, water and nitrogen cycles

There is no___ phase of Phosphorus

Gas phase (Phosphorus doesn’t enter the Atmosphere)

It takes a long time for phosphorus ____ To be weathered out Of rocks and carried into soil/bodies of water

Minerals

Plant growth is often ____ By phosphorus, availability in soil/water

Limited (Since the cycle is so slow)

Phosphorus is needed by all organisms for

DNA,ATP (Energy), Bone and tooth enamel and some animals

What is a Major natural source of phosphorus

Weathering of rocks that contain phosphorus minerals

-Wind and rain break down Rock and phosphate is released and dissolved into water rainwater carries phosphate into nearby soils and bodies of water.

-weathering is so slow that phosphorus is often a limited nutrient in terrestrial and aquatic ecosystems

Synthetic sources of phosphorus

Mining phosphate minerals, and adding to products like synthetic fertilizer and detergent/Cleaners

-synthetic fertilizers containing phosphates are added to lawns or agriculture; Runoff carries phosphorus into nearby bodies of water

Assimilation

Phosphorus is absorbed by plant roots and assimilate into tissues; animals assimilate, phosphorus by eating plants or other animals

Excretion/ decomposition

Animal waste, plant matter and other biomass is broken down by bacteria/soil decomposers that return phosphate to soil

Sedimentation

Phosphate doesn’t dissolve very well into Water; Much of it forms solid bits of phosphate that fall to the bottom as sediment

-phosphorus sediments can be compressed into sedimentary rock over long time periods by pressure of overlying water

Geological uplift

Tectonic Plate collision, forcing up rock layers that form mountains; Phosphorus cycle can start over again with weathering and release of phosphate from rock

Eutrophication can occur…..

From fertilizer runoff human/animal waste contamination

Eutrophication

Because they’re limiting nutrients and aquatic ecosystems extra input of nitrogen and phosphorus lead to eutrophication, which is an excess of nutrients which fuels algae growth

Algae blooms, cover surface of water blocking ____ And _____ Plants below the surface

Sunlight, Killing

Creates a pos feedback loop

less O2—> more dead organisms ——> more bacterial decomposition——> less O2

Bacteria use up even more ___ To decompose dead aquatic animals

O2

Lower ___ levels (Dissolved oxygen) And water kills aquatic animals, especially fish

O2