Geoscience Reference
In-Depth Information
profoundly linked to the Turing patterns - which can exhibit spots, stripes, squares,
hexagon, and other geometrical figures - mechanism, meaning that non-extensive
statistical mechanics (with the use of the q -entropy S q ) can be applied to the study
of the Turing patterns with fractal clustering behavior exhibited in nature, on Earth,
and on Mars.
Thus, the use of LLV models and Turing mechanisms, also by means of the non-
extensive statistical mechanics, can mathematically describe well the phenomena
of clustering and their associated boundaries with fractal dimensionality, which
occurs in various natural situations, among them, biogeochemical processes via
microorganisms in estuarine and marine sediments on planet Earth.
An estuary is a semi-enclosed coastal body of water with one or more rivers or
streams flowing into it and with a free connection to the open sea (Pritchard 1967 ).
An estuary is typically the tidal mouth of a river, and estuaries are often charac-
terized by sedimentation or silt carried in from terrestrial runoff and, frequently,
from offshore. They are made up of brackish water. Estuaries are more likely to
occur on submerged coasts, where the sea level has risen in relation to the land; this
process floods valleys to form rias (a ria is a submerged marine coastal landform,
often known as a drowned valley or drowned river valley; rias are almost always
estuaries) and fjords (fjords are very long inlets from the sea with high steeply
sloped walled sides; a fjord is a landform created during a period of glaciations).
These can become estuaries if there is a stream or river flowing into them.
Estuaries and coastal marine waters are among the most biological productive
ecosystems on Earth. And if there is enough liquid water on Mars in the past
to produce such geological watery environments, then probably, biogeochemical
evolution might have took place on such locations.
Sediments are characterized by heterogeneous distributions of nutrients and
microorganisms which emerge as a result of the interaction between chemical and
biological processes with physical transport. It was studied in a simplified model
the dynamics of one population of microorganisms and its nutrients, taking into
account that the considered bacteria possess an active as well as an inactive state,
where activation is processed by signal molecules. Furthermore, the nutrients are
transported actively by bio-irrigation.
It is shown that under certain conditions, Turing patterns can occur which yield
heterogeneous spatial patterns of species. Furthermore, this model exhibits several
stable coexisting spatial patterns. This phenomenon of multistability can still be
observed when spatial patterns are externally imposed by considering a depth-
dependent bio-irrigation. The influence of bio-irrigation on Turing patterns leads to
the emergence of “hot spots,” i.e., localized regions of enhanced bacterial activity.
This above work did not take into account temporal behavior of the Turing patterns
(the Turing mathematical mechanism also has a temporal degree of freedom within
its space-time matrix metric dynamics).
I did an experimental analysis in fieldwork which took into account the spatial
and temporal behavior of Turing patterns, in the form of microbial activity within
estuarine subsurface sediments. The region of study was a flat region with a
small tidal estuarine, a very shallow river (0.05 m depth 0.5 m) named Caraís
Search WWH ::




Custom Search