Morphology and anatomy Anthemis caucasica Chandjian (Asteraceae Dumort.) in Alpine lichen tundra northwest Caucasus

We have studied the morphological and anatomical structure of Anthemis caucasica Chandjian – theendemic of alpine zone of the Caucasus. The plant is characterized by protection from hard ultraviolet radiation, a largesupply of nutrients, moderate growth and flowering. Horizontally lying rhizomes are optimal for occupying highly stonyareas with low competition.

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ECOLOGICAL AND CENOTIC ANALYSIS OF PTERIDOFLORA SPECIES REGISTERED ON THE TERRITORY OF THE ABKHAZIAN FLORISTIC REGION OF THE CAUCASUS

Ekosistemy ◽

10.37279/2414-4738-2020-21-5-17 ◽

2020 ◽

Vol - (21) ◽

pp. 5-17

Author(s):

S. A. Litvinskaya ◽

D. А. Makhlin

Keyword(s):

Endemic Species ◽

Limiting Factor ◽

Forest Edges ◽

The Caucasus ◽

Alpine Zone ◽

Altitudinal Belts ◽

Mountain Belts

The geographical, ecological and cenotic analysis of pteridoflora species registered on the territory of the Abkhazian floristic region of the Caucasus is carried out. In this region Polypodiopsida is represented by 4 monophyletic orders, 8 families, 25 genera and 55 species. Fourteen types of geoelements are identified there. Five endemic species grow within the region, local endemics include Asplenium woronowii Christ., Polystichum woronowii Fomin, Asplenium hermanii-christii Fomin and Dryopteris alexeenkoana Fomin. In environmental terms, humidity regime is the limiting factor for pteridoflora. Mesomorphic structure is typical for 44 species, of which 31 species belong to mesophytes, 13 – to hygromesophytes. According to the phenorhythmotype, 12 species of ferns are evergreen, 27 species are summer-green, 9 are winter-green. Forty-three species were recorded in the forest. The second place is taken by rocky ecotopes: 21 species grow in forest edges, meadows, highlands. The largest number of pteridoflora was observed in mixed (24 species), oak-hornbeam (23 species), beech (22 species), alpine zone (19 species) and dark coniferous (14 species) forests. Rock substrates are found in all types of vegetation and mountain belts, where several types can be distinguished: Moraenapetrophyton, Schistopetrophyton, Petrophyton, Pratopetrophyton and Sylvapetrophyton. Coenotic variability and distribution in altitudinal belts of the types of pteridoflora is considered.

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Anatomical Review of Certain Carnations of North Caucasus

KnE Life Sciences ◽

10.18502/kls.v4i14.5650 ◽

2019 ◽

Author(s):

E Sh Dudagova ◽

M A Taisumov ◽

H Z Mantaev ◽

M U Elipkhanov ◽

M A-M Astamirova ◽

...

Keyword(s):

Botanical Garden ◽

Anatomical Structure ◽

Limiting Factor ◽

North Caucasus ◽

Natural Conditions ◽

The Caucasus ◽

Anatomical Features ◽

Adaptive Capabilities ◽

State Pedagogical ◽

Well Differentiated

The article provides an anatomical review of 32 species of the genus Dianthus L. representatives шт Caucasus, i.e. information about the anatomy of their stem. Most of the studied species have a narrow ecology and are confined to different altitudinal zones. The experience of the introduction of these species in the botanical garden of the Chechen State Pedagogical University of Grozny in the conditions of the steppe climate indicates wide ecological amplitude and potential adaptive capabilities of the species. The main limiting factor in the distribution of these species in natural conditions is probably their low competitiveness. Anatomical signs, apparently, do not have any taxonomic significance. The similarity of the anatomical structure of the stems of the Caucasus carnations is evident even in species that are well differentiated morphologically. Anatomical differences between them are mainly quantitative. The smallest taxonomic values for the anatomical features of carnations are the radial dimensions of the epidermal cells, the mechanical (sclerenchymal) ring, conducting system. The most significant for these purposes are the morphological features: the size of the calyx and capsule, the shape and degree of dissection of the lobule plate, the shape and size of the chaffs.

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Revealing the stygobiont and crenobiont Mollusca biodiversity hotspot in the Caucasus: Part III. Revision of stygobiont microsnails (Mollusca: Gastropoda: Hydrobiidae) from the Russian part of Western Transcaucasia, with the description of new taxa

Zootaxa ◽

10.11646/zootaxa.5005.3.2 ◽

2021 ◽

Vol 5005 (3) ◽

pp. 257-275

Author(s):

ELIZAVETA M. CHERTOPRUD ◽

DMITRI M. PALATOV ◽

MAXIM V. VINARSKI

Keyword(s):

Taxonomic Revision ◽

Balkan Peninsula ◽

Anatomical Structure ◽

Nominal Species ◽

New Genera ◽

The Caucasus ◽

Krasnodar Krai ◽

Separate Genus ◽

First Time ◽

North Western

A taxonomic revision of the stygobiont microsnails from north-western Transcaucasia (Krasnodar Krai, Russia) is presented. Two new genera—Schapsugia gen. n. and Tachira gen. n. are established. It is shown that the genus Paladilhiopsis does not occur in this area, and the snails previously assigned to this genus belong to Schapsugia gen. n. Two nominal species Paladilhiopsis orientalis Starobogatov, 1962, and P. subovata Starobogatov, 1962 are considered junior synonyms of Sch. pulcherrima (Starobogatov, 1962), based on a re-examination of their conchological variation. In addition, two more species of Schapsugia are described: Sch. kudepsta sp. nov. and Sch. occultata sp. nov. The anatomical structure of another species, Geyeria valvataeformis Starobogatov, 1962 was studied for the first time. It is revealed that it should be placed in a separate genus (Tachira gen. n.). Thus, the previously proposed placement of the microsnails from north-western Transcaucasia in hydrobiid genera from the Balkan Peninsula (Geyeria, Paladilhiopsis) is rejected.

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Applications of Photoelectron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092499 ◽

1976 ◽

Vol 34 ◽

pp. 506-507

Author(s):

William J. Baxter

Keyword(s):

Electron Microscopy ◽

Thermal Decomposition ◽

Chemical Composition ◽

Ultraviolet Radiation ◽

Thin Layer ◽

Edge Effects ◽

Electron Optics ◽

Surface Layers ◽

Crystalline Orientation ◽

Fluorescent Screen

In this form of electron microscopy, photoelectrons emitted from a metal by ultraviolet radiation are accelerated and imaged onto a fluorescent screen by conventional electron optics. image contrast is determined by spatial variations in the intensity of the photoemission. The dominant source of contrast is due to changes in the photoelectric work function, between surfaces of different crystalline orientation, or different chemical composition. Topographical variations produce a relatively weak contrast due to shadowing and edge effects.Since the photoelectrons originate from the surface layers (e.g. ∼5-10 nm for metals), photoelectron microscopy is surface sensitive. Thus to see the microstructure of a metal the thin layer (∼3 nm) of surface oxide must be removed, either by ion bombardment or by thermal decomposition in the vacuum of the microscope.

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