Zonation


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Related to Zonation: Vertical zonation

zonation

[zō′nā·shən]
(ecology)
Arrangement of organisms in biogeographic zones.
(geology)
The condition of being arranged in zones.

Zonation

 

(geographic), the pattern of differentiation of the geographic sphere (landscape) of the earth, manifest in the sequential and definite change of geographic belts and zones and resulting primarily from differences in the amount of solar energy reaching particular latitudes on the earth’s surface.

Zonation is also characteristic of most of the components and processes of the natural geographic regions—climatic, hydrological, geochemical, and geomorphological processes; the soil, plant cover, and animal life; and to some extent the formation of sedimentary rocks. A decrease in the angle of the sun’s rays as they strike the earth from the equator to the poles creates broad latitudinal belts of radiation: a tropical zone, two temperate zones, and two cold zones. The formation of analogous belts, especially climatic and geographic belts, is related to the characteristics of the atmosphere and atmospheric circulation, and these are strongly influenced by the distribution of land and oceans, which is not zonal. The differentiation of natural zones on land depends on the pro-portion of heat and moisture, which changes not only with latitude but also from the coastal area to the continental interior (patterns of sectionalization). Thus it is possible to speak of horizontal zonation, which is particularly well shown by the latitudinal zonation on the plains of the USSR. Each geographic belt and sector has its spectrum and sequential order. Zonation is also expressed in the regular progression of altitudinal zones, or belts, in mountains, which is originally determined by a nonzonal factor, the relief; moreover, definite spectra of altitudinal zones are characteristic of particular belts and sectors. Both horizontal and vertical zonation are expressed in oceans (by consecutive changes in temperature, salinity, biocomponents), over which geographic belts extend.

Zonation of thermal conditions was recognized as early as classical times. Climatic and plant zonation, including altitudinal zonation, was established by the German scientist A. von Humboldt. Zonation was first defined as a fundamental law of differentiation of major natural complexes by V. V. Dokuchaev in 1898.

E. N. LUKASHOVA

References in periodicals archive ?
The zonation method provides a replicable means to assess fragmented remains, regardless of the degree of fragmentation or the number of analysts working on a project.
From the history of landslide events in the Darjeeling Himalayas, it is concluded that the study area is vulnerable to landslides, and hence, the landslide susceptibility zonation map for the study area is required to be analyzed.
Study on the phylogeny, taxonomy, zonation and biofacies of Siphonodella (Conodonta).
The results obtained on cultural characteristics viz., colony/mycelial growth, growth rate, colony appearance, margin, sporulation and concentric zonation etc in respect of 20 test isolates of A.
The internal zonation of the calcite crystals is also observable when the longitudinal thin sections cross-cut the belemnite rostra offset from the apical line (Fig.
At each site, the samples for each species were obtained from portions having different orientations towards the sun, to include possible light-related zonation patterns in zooxanthellae types.
Using the Chernobyl Nuclear Power Plant disaster in Ukraine as a case study, this volume describes the assessment of groundwater vulnerability and an improved methodology based on integration of the methods of hydrogeological zonation and modeling of anomalously fast migration of radioactive contaminants from the land surface toward groundwater, to aid in evaluating groundwater vulnerability and conducting risk assessments for groundwater contamination from diverse sources, as well as selecting optimal remediation methods for reducing threats from residual radioactivity.
until present time (Mohamad Tarmizi, 2014), the pollens of Stemonurus and Gonostylus are observed present indicating that vegetational successive zonation of phasic community II has developed and may have been reached, but without the appearance of the Shorea type pollen (however, the large, Shorea type trees have been observed present in the field near to locations KS.TP.09 and KS.TP 10).
The students also listened to explanations by EMRQ's experts on geological core exploration; coral reefs and coral reef zonation; and marine environments.
Spatial zonation of landslide occurrences, also known as landslide susceptibility mapping, aims to differentiate a land surface into homogeneous areas according to their degree of failure caused by mass movement at specific locations [2].
One disadvantage of biochemical analyses is that they are performed on homogenates that do not allow the contribution of the single cell types and the possible influence of metabolic zonation to be appraised.
The Harena mineralization displays a consistent metal zonation pattern, with a sphalerite and pyrite, zinc-rich upper zone and a chalcopyrite and pyrite, copper-rich basal zone.