Geoscience Reference
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Fig. 1.44 The scheme of
sulfur fluxes in the
environment (MGBS unit of
the BCSS global model). The
notation is given in
Tables
1.16
and
1.17
in the movement of phosphorus. In contrast to nitrogen, the main reservoir of
phosphorus in the biosphere is not the atmosphere but the rocks and other deposits
formed in the past geological epochs, which, being subject to erosion, emit phos-
phates. Besides, there are other mechanisms of the return of phosphorus to the
biospheric cycle, but, as a rule, they are not that ef
cient. One of these mechanisms is
10
3
t P/year, as well
fish catching, returning to land from the hydrosphere about 60
×
10
6
t P/year. The
as an extraction of phosphorus-containing rocks estimated at 1
2
×
-
present cycle of phosphorus is closed by its
fluxes to the bottom deposits in the
World Ocean to which it gets with sewage, as well as with the coast and river run-off.
Schematic diagrams of global phosphorus cycle are represented in Figs.
1.45
and
1.46
. They re
fl
fl
ect main processes of phosphorus in the environment:
phosphorus is an essential nutrient for plants and animals which use of it to build
nuclei acid, phosphorus bilayer, and adenosine triphosphate;
phosphorus minerals are used to build strong bones and teeth;
phosphorus comes from dead organic matter and from the weathering/erosion of
phosphates from rocks; and
plants get it from the soil and animals get it from eating plants.
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