The phosphorus cycle is the biogeochemical cycle that describes the movement of phosphorus through the lithosphere,

hydrosphere, and biosphere. unlike many other biogeochemical cycles, the atmosphere does not play a significant role in the

movement of phosphorus, because phosphorus and phosphorus-based compounds are usually solids at the typical ranges of

temperature and pressure found on earth. one important source of soluble phosphorus is the weathering of certain minerals. the

most common source of phosphates in the soil is the weathering of

a)

the mineral apatite.

mineral fertilizers.

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clays and iron oxides.

microbial action on manure.