Phosphorus Cycle

What is Phosphorus?• Is an essential

nutrient for plants and animals in the form of ions.

• Phosphorus is also a building block of certain parts of the human and animal body.

What is Phosphorus Cycle?

• The phosphorus cycle is the biogeochemical cycle that describes the movement of phosphorus through the lithosphere, hydrosphere, and biosphere.

• Low phosphorus availability slows down microbial growth

Ecological Function• Is an essential nutrient for plants and

animals in the form of ions. Phosphorus is a limiting nutrient for aquatic organisms.

• Eighty percent of the mined phosphorus is used to make fertilizers.

• Enrichment of phosphate can lead to eutrophication of fresh and inshore marine waters.

Biological Function• The primary

biological importance of phosphates is as a component of nucleotides.

• It also functions as buffering agent in maintaining acid base homeostasis in the human body.

Process of the Cycle

• Phosphates moves quickly through plants and animals.

• Unlike other cycles of matter compounds, phosphorus cannot be found in air as a gas, it only occurs under highly reducing conditions as the gas phosphine PH3.

• Phosphorus is typically the limiting nutrient found in streams, lakes and fresh water environments.

• The small losses in a terrestrial system caused by leaching through the action of rain are balanced in the gains from weathering rocks.

• Herbivores obtain phosphorus by eating plants, and carnivores by eating herbivores.

• Phosphorus is released back to the soil when plants or animal matter decomposes and the cycle repeats.

Phosophatic Minerals• The availability of phosphorus in

ecosystem is restricted by the rate of release of this element during weathering.

• The release of phosphorus from apatite dissolution is a key control on ecosystem productivity

• Plant and animal growth depends on the rate of their degradation to generate free phosphate

Human Interference

• Humans alter the cycle by:

1. Cutting the tropical rain forest2. The use of agricultural

fertilizers3. The use of laundry detergents

What is natural eutrophication?

Thanks :)