Organic sediment on lake bottoms and the ocean floor is broken down by microbes into inorganic forms of phosphorus in a process known as

Eutrophication

Explanation:

Organic sediments at the bottom of the lakes and at the bottom of the ocean are broken down by microbes into inorganic phosphorus forms in a process known as eutrophication.

Eutrophication (or eutrophication) is a process usually of anthropic origin (caused by man), or rarely of a natural nature, having as its basic principle the gradual concentration of accumulated organic matter in aquatic environments. Among the impact factors, contributing to the increasing pollution rate in this ecosystem, are: domestic waste (sewage), agricultural fertilizers and industrial effluents, directly discharged or percolated towards watercourses (rivers and lakes, for example).

During this process, the excessive amount of minerals (phosphate and nitrate) induces the multiplication of microorganisms (algae) that inhabit the surface of the water, forming a dense layer, preventing the penetration of light.

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