Ecology: The Biology of Interactions. 2.09. The Biogeochemical Cycle of Phosphorus
The BGC cycle of phosphorus is regulated much less effectively than the carbon and nitrogen cycles considered above, because phosphorus lacks an exchange pool in the atmosphere. Phosphorus is the principal element controlling the productivity of aquatic communities. The runoff of phosphates from fields into water bodies leads to their eutrophicati...
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2.08. Biogeochemical Cycle of Sulfur
D. Shabanov, M. Kravchenko. Ecology: Biology of Interactions Section 2. Biospherology
2.10. (addendum) Evolution of the Universe, the Solar System, and Earth
2.09. Biogeochemical cycle of phosphorus The P cycle (Fig. 2.9.1) is much less regulated than the carbon and nitrogen cycles just discussed, because phosphorus lacks an atmospheric exchange pool. Phosphorus is the main element that controls the productivity of aquatic communities. The role of phosphates in these communities is demonstrated by an experiment with halves of a pond, where sucrose and nitrates were added to one part, separated by a plastic partition, and phosphates were also added to the other part. The second half bloomed, the first did not. The runoff of phosphates from fields into water bodies leads to their eutrophication (an increase in "feed content" as opposed to oligotrophy - "low feed content"), which can lead to their swamping. In naturally eutrophic water bodies (in which most of the biogens and organic matter are autochthonous), the community effectively utilizes production. With eutrophication due to external intervention (when biogens and organic matter are allochthonous), an excess of organic matter can arise, the decomposition of which will lead to the creation of anaerobic conditions, the release of toxic decomposition products (hydrogen sulfide, ammonia), the destruction of the community, and rapid swamping. Fig. 2.9.1. Global phosphorus cycle Additional materials: Column: Phosphorus-free diet? Ukrainian / Russian
2.08. Biogeochemical Cycle of Sulfur
D. Shabanov, M. Kravchenko. Ecology: Biology of Interactions Section 2. Biospherology
2.10. (addendum) Evolution of the Universe, the Solar System, and Earth