Geoscience Reference
In-Depth Information
• It is well defined that a chemical element is preferentially stored in one
of the pools and is, at this level, to be found in more or less stable chemical
combinations.
The exchanges among the various compartments of the hydrogeomor-
phological units and the troposphere are made very slowly (at a time scale
of geological processes) and are supplied by physical, chemical, and geo-
logical processes. In the case of most chemical elements, there is at least
one pool where they can be partially found in more unstable combinations
and are consequently available to the primary producers in a network of
tropho-dynamic modules.
Thus, the primary cycling process, which involves physical, chemical,
and slowly evolving geological phenomena and mechanisms, overlaps the
secondary cycling process. And, as a result, it is supported by much faster
physical, chemical, and biological mechanisms and phenomena. In between
these cycling processes, which take place on different levels and at various
rates, are established contacts and exchanges that are identifiable in the
more dynamic compartments, reservoirs, or pool. These usually lead to
either an increase of the recyclable stock or a decrease due to the leaks from
and to the primary cycling system.
The following section refers to the fast cycling system that involves the
intervention of the biological components, which strictly conditions the
ecological systems' functioning as productive units.
•
Consider the complexity of homomorphic models through which each
ecological system is identified by relating the variety of coupled mecha-
nisms ensuring the cycling of the elements, as well as their dynamics,
according to the key driving forces. From this we can understand the
requirements and standards in researching and monitoring biogeochemical
cycles and also the reason for the underlying long distance and time delay
between the place and moment when a significant change of a driving force
occurs and when the effects are recorded. Further, the same structure
represents the cycling support for all the chemical elements (including the
heavy metals and radionuclides) and for man-made chemical compounds.
This fact accounts for the accumulation of the effects. The complexity of
biogeochemical cycles as being the fundamental processes of the ecolog-
ical systems has valuable significance. This is especially important for
managers, decision makers, and politicians who want to apply programs
for sustainable use of NC and to prevent deterioration of the quality of
resources (e.g., water, air, soil, biological) and human health.
In addition to the above statement, we may add a complementary series of inter-
pretations that are intended to be taken as important coordinates of the decision-making
process and management sustainable use and development goals. (See
Chapter 8
for
details.)
•
Biogeochemical cycles of chemical elements and compounds are associated
with the energy flow, thus supporting and strictly controlling the quality and
amount of resources and services provided by ecological systems.
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