Cyanobacterial Diversity of the Northern Polar Ural Mountains

This study provides new results from an inventory of cyanobacterial species from the Northern Polar Ural Mountains. The article also compiles all existing published data on the cyanobacterial diversity of the region. This ecoregion is located in a unique geographical position in the transition between the sub-Arctic and low Arctic zones and heterogeneous natural conditions. Likely, the unexplored biodiversity of this area’s terrestrial cyanobacteria is high. In total, 52 localities were studied, with 232 samples collected. Cyanobacterial samples were studied under a light microscope. Species were identified based on morphological characteristics only. A total of 93 species of cyanobacteria were identified in different habitats; 70 species were found on wet rocks, 35 on the shores of water bodies, 27 in slow streams, and 21 on waterfalls. In total, 37 species are reported as part of the Ural flora for the first time, while three species (Chroococcus ercegovicii, Gloeocapsopsis cyanea, Gloeothece tepidariorum) were detected in Russian territory for the first time. The composition of the cyanobacterial flora of the Polar Urals was compared with the flora of the nearby Arctic and sub-Arctic regions. According to the Sorensen similarity index, the Polar Urals’ flora is more like the flora of Nenets Autonomous Okrug.

Pollen spectra of Polar Ural glaciers

The subject of this article is the pollen spectra of the samples from the surface of Romantic's Glacier, located in the Polar Urals in the Rai-Iz mountain range, as well as generalization of the results of published studies dedicated to glaciers of the Urals. The author also examines the pollen spectra of massive ice, which can be attributed to ice of atmospheric origin on the basis of similarity with the pollen spectra obtained from the surface of the glacier. The article reviews climatic peculiarities of the Polar Urals due to the existence of glaciers below the snow line, namely the landscapes of the Polar Urals, including vegetation as a source of pollen and spores falling onto the surface of glaciers of the Polar Urals, as well as possibility of distant pollen drift to the surface of Romantic’s Glacier. The main result consists in the conclusion that the composition pollen spectra of the Romantic’s Glacier in the Rai-Iz mountainous area is mainly determined by the long-range transport of pollen and spores from the western and south-western regions in a latitude direction. The pollen spectra obtained from the surface of the Romantic’s Glacier are characterized by significant presence of various pollen from broad-leaved rocks of lip, maple, oak, and hazel. Pine pollen and high forest birch are prevalent. Local vegetation is very poor. However, the pollen spectra indicates pollen of heath and crowfoot family, and grasses.

MAFIC INCLUSIONS (SOBSKY COMPLEX, POLAR URAL): U‐Pb (SIMS) DATA

The rocks of the Sobsky complex, composing the bulk of the Sobsky batholith in the Polar Urals, contain mafic inclusions. The geological, petrographic and petro‐geochemical data show that the mafic inclusions of the Sobsky rocks belong to igneous formations, which are similar in their characteristics to autoliths. According to all the characteristics, these are the structures non‐contrasting to host rocks and having different structural‐textural features, a more basic composition of minerals and a more basic composition of rocks. The contact with the rocks of the complex is sharp and clear. The rocks of the complex in contact with autoliths are medium‐grained massive diorite rocks, quartz diorites, tonalites, mafic inclusions rocks – fine‐grained gabbros, gabbro‐diorites, and diorites. Isotopicgeochemical (U‐Pb, SIMS) data on zircons from the mafic inclusions suggest that their age is close, within the error limits, to the age of zircons from the enclosing Sobsky complex rocks.