Pseudocontinuation and cyclicity for random power series

We prove that a random function in the Hardy space $H^2$ is a non-cyclic vector for the backward shift operator almost surely. The question of existence of a local pseudocontinuation for a random analytic function is also studied

Characterisation of humic acids, isolated from selected sub-antarctic soils by 13C-NMR spectroscopy

Soils of Antarctic considered as underestimated in terms of soils organic matter polls, organic remnants humification/mineralization rates and biogenic-abiogenic interactions. Humic acids of selected Sub Antarctic soils were investigated in terms of elemental and structural composition with special reference to evaluation of organic matter stabilisation degree and assessment of carbon species distributions in the molecules with use of solid state 13C-NMR spectroscopy. It was shown, that the prevailing of aliphatic compounds on the aromatic one is more pronounced in Antarctic soils than in Arctic ones. Average portion of the aromatic compounds is about 20% in humic acids, extracted from soils with evident ornitogenic effect from Fildes Peninsula (Norh-West Antarctic peninsula). This indicates that the role of humification precursors composition is the leading in the humification process. The stabilisation rate of the Antarctic HAs can be assessed as low and the potential risk of biodegradation of their molecules are high

Vertical electric resistivity sounding of natural and anthropogenically affected cryosols of Fildes Peninsula, Western Antarctica

Natural and anthropogenically-affected Cryosols of the Fildes Peninsula (King George Island, NWAntarcticPeninsula) from the surroundings of Russian polar station Bellingshausen were investigated by vertical electric sounding. The aim of the study was to asses the thawing depth and active layer thickness. Natural Turbic Croysols showed lesser thickness of active layer than the soils of former reclaimed wastes disposals. Average thickness of the active layer was 0.3-0.4 m in natural soil and 1.3-1.4 m in anthropogenically-affected ones. This was affected by the change in the temperature regime of soils, and related to the destruction of upper organic layer and mechanical disturbance of the active soil layer on the waste polygons. Itwasshown,thattheuseof vertical electric soundingmethodologyinthesoilsurveysisusefulfor the identificationofthe permafrostdepthwithoutdiggingofsoilpit.Thismethodallowstheidentificationofsoilheterogeneity, because the electric resistivity (ER) values are strongly affected by soil properties. ER also intensively changes on the border of differentgeochemicalregimes,i.e.ontheborderoftheactivelayerandthepermafrost. The lowest ER values were found for the upper organic horizons, the highest for permafrost table. Technogenic Superficial Formations exhibit lower resistivity values than natural soils. Therefore, disposition of WP and disturbance of the soil surface, results in permafrost degradation and an increase in the active layer thickness.

Permafrost-affected former agricultural soils of the Salekhard city (Central part of Yamal region)

Soil cover transformation in Russian Arctic is considered as underinvestigated. In 1920s it was started systematical studying and exploitation of natural resources of Far North of Russia. Due to development of industry and growth in area population necessity in agricultural products was growing intensively and arable soils became typical component of the soil cover in polar cities surroundings. Nowadays, however, almost all the former cultivation fields are abandoned or in poor use. Abandoned agricultural soil in sub urban territories of the Salekhard city were studied with aim to evaluate alteration of soil morphology and chemistry under agricultural impact and clarify the specificity of this process in case of permafrost-affected soils. The predominance of sandy textured parent materials within Salekhard city area was one of the main reason of favorable agricultural using of land in the north of Western Siberia in previous years. Data obtained revealed that studied soils are characterized by properties caused both by former (or existing) anthropogenic influence and natural processes (e.g. cryogenic mass transfer). Soil organic carbon content depends mainly on the character of current land use and varies significantly in studied soils. Most of the soil samples showed the highest levels of soil nutrients in the topsoil. Former arable horizon is stable in time in terms of morphological features and agrochemical state. In spite of high level of soil acidity, content of nutrients in antropogenically affected topsoils is still high after 20 years of abandoned state of soils. This indicates that agrosoils with relatively high fertility of arable topsoils could exist during long time in case of sandy-textured parent materials