phosphorus cycle

phosphorus cycle

1. main processes

   • root absorption
     • needed for metabolic processes, symbiotic relation ships with fungi allow this plants plants them self are not effective at absorption
   • decomposition
     • breakdown of phosphorylated proteins in dead organic matter that is often made more soluble by microbes in the soil
   • sedimentation
     • phosphorous in organisms that is lost when they die and become incorporated with the sediment, making them no longer avaliable to other organisms e.g plankton that die and sinks to the bottom of the sea bed
   • mountain building and weathering
     • processes that mobilise phosphorous are slow

2. Human impacts

   • mining of phosphate rocks
     • mainly mined as calcium phosphate and that converted into ammonium phosphate which is more soluble
   • fertiliser use
     • mobilises phosphorus compounds in the environment in more soluble forms

3. sustainable management

   • reduced by removal of biomass in crop harvesting and soil erosion
   • use of biological waste as fertiliser to maintain phosphate nutrient availability