Sergey Loiko

National Research Tomsk State University · BioGeoClim Laboratory

The fall of a tree accompanied by its uprooting is the most common natural end of the tree life. To understand how soil is affected by treefalls, it is necessary to recognize their signs in soil profiles, even when their surface features (pit-and-mound topography) are erased. The paper reviews these signs of treefalls in soil profiles, which can be...

Thawing of frozen peat in discontinuous permafrost zones may significantly modify the environment at local (slumps and engineering damages) and global (greenhouse gases regime) scales. We studied the aquatic geochemistry of CO2, CH4, dissolved organic carbon (DOC), P, Si, and colloidal trace metal from hollows, depressions, permafrost subsidences a...

Buried soils within aeolian deposits are considered an important tool for diagnosing, determining the age, and estimating the intensity of aeolian processes at the transition from the Pleistocene to the Holocene in the Northern Hemisphere. Late Pleistocene aeolian coversands and ancient inland dunes are widely distributed in the periglacial zone of...

Climate warming, increased precipitation, and permafrost thaw in the Arctic are accompanied by an increase in the frequency of full or partial drainage of thermokarst lakes. After lake drainage, highly productive plant communities on nutrient-rich sediments may develop, thus increasing the influencing greening trends of Arctic tundra. However, the...

In contrast to good knowledge of dissolved organic matter (DOM) adsorption on mineral soils in temperate climate, the behavior of DOM in frozen mineral horizons located under peat soils of permafrost-affected regions remains poorly characterized. Yet, these regions contain sizeable and potentially highly labile pools of organic (peat) carbon (C) th...

The soils and vegetation of Arctic floodplains are vulnerable to global warming because, in addition to climate change, they are affected by the changing hydrological regime of rivers. However, for river floodplains in large Arctic regions, such as the Yamalo-Gydan ecoregion, even descriptive field studies are still very incomplete. Therefore we st...

Climate change in the Arctic may increase the incidence of tundra fires, which is expected to significantly transform tundra ecosystems. Therefore, it is promising to study the tundra paleofire data to assess whether the projected increase in fire numbers is unique. In this study, we used five types of ancient fire proxies to estimate the number of...

The impact of human activity on soil carbon stock and soil fertility is at the forefront of scientific research. In the past, human practices improved soil fertility and increased carbon storage over long periods of time. Studying the resulting anthrosols provides access to their evolution over time scales that are unavailable otherwise. These arch...

The aim of the study was to investigate the historical land use and identify abandoned land aras of different ages within the area occupied by the dark-grey forest soils (according to the USSR Soil Classification of 1977), or as Luvic Greyzemic Phaeozems (according to the World Reference Base for Soil Resources of 2022) in one of the oldest agricul...

Of particular interest in the north of Western Siberia are frozen flat-mound bogs. Being formed in a transitional climatic zone, on the southern front of the permafrost zone, these frozen peatlands may turn out to be highly reactive upon thawing and deliver high amounts of solutes to the hydrological network. A detailed study of a flat-mound bog wa...

Arctic environments are covered by millions of km² of permafrost-affected wetlands. The lowlands of Western Siberia are one of the largest of such areas. The low vegetation cover of these wetlands consists of Sphagnum moss, lichen, and peat. The spatial distribution of this vegetation layer is mainly driven by microtopography (Loiko et al., 2019)....

The impact of wildfire on terrestrial and aquatic ecosystems in permafrost-affected regions is a major and still poorly understood consequence of climate warming in high latitudes. Towards better characterization of processes controlling post-fire nutrient migration and to establish the relationship between forest litter and aquatic systems during...

This presentation aims at giving an overview of the porous media related activities of the HiPerBorea project, an ANR-funded project in its 5th and last year. The objective of this project is to enable quantitative and predictive modeling of the evolution under climate change cold regions hydrosystems. Arctic and sub-arctic areas, which are highly...

The paper presents the preliminary results of paleopedological studies of the complex archeological site Bolshoi Salym 4, located in the central part of the West Siberian Plain. The study results have shown that the strata within this locality is complicated by polygonal paleocryogenic structures, filled with the material of Early Holocene paleosol...

Потепление климата может привести к сильной трансформации многих криогенных геосистем мира. Особенно уязвимы высокогорные мерзлотные торфяные массивы пальза, имеющие сравнительно небольшую площадь. Нами были изучены четыре таких массива, почвы которых диагностируются как Cryosols, в пределах Арабельского плато Центрального Тянь-Шаня. Показано, что...

Towards a better understanding of factors controlling carbon (C) exchange between inland waters and atmosphere, we addressed the inorganic carbon cycle in semiarid lakes of Central Eurasia, subjected to the strong impact of on-going climate change. As such, we assessed the hydrochemical variability and quantified its control on the formation of aut...

Towards better understanding of factors controlling carbon (C) exchange between inland waters and atmosphere, we addressed inorganic carbon cycle in semi-arid lakes of Central Eurasia, subjected to strong impact of on-going climate change. For this, we assessed the hydrochemical vari-ability and quantified its control on formation of authigenic car...

The global climate change and significantly increased anthropogenic pressure on the Arctic and Subarctic regions require modern ecosystem monitoring and understanding of the past environmental changes. Vegetation history is reflected by pollen spectra recorded in peat deposits, investigation of which is one of the main methods in the research of lo...

West Siberian wetlands act as important indicator and regulator of climate change on a global scale. The northern taiga of the sporadic permafrost is one of the most warming-sensitive regions undergoing dramatic changes. Carbon cycling in wetlands is strongly affected by hydrology, in addition to temperature and associated with microtopography. Tak...

In arctic regions, a complex patchwork of low vegetation layer consisting of Sphagnum moss, lichen, and peat covers the permafrost active layer on millions of km2, for instance in the lowlands of Western Siberia. Assessing the properties of this layer is crucial for modeling of soil thermal regimes, since this vegetation layer is the main interface...

The Chernevaya taiga is a unique ecosystem formed under the influence of a complex of geogenic and bioclimatic factors located in the foothill border of the southeastern part of Western Siberia. The combination of local climatic conditions and the composition of parent material led to the formation of specific soil conditions on the territory of th...

Climate warming has significantly impacted the ecosystems of the Subarctic and Arctic. It has most strongly affected highly productive ecosystems, including those formed in river floodplains. Due to the initially high (background) values of NDVI, remote monitoring methods are not suitable for detecting changes in the biological productivity of floo...

The proposed paper is devoted to the analysis of the urbanization effects on soil cover using physico-chemical parameters and stable isotopic signatures on the example of Tyumen. The study methods included analysis of C and N elemental and isotope (δ¹³C and δ¹⁵N) composition, analysis of soil physico-chemical properties and major oxides content. Th...

Climate warming in the Subarctic leads to the expansion of shrub ecosystems. The most common upland tundra shrubification is by alder in combination with dwarf birch and willows. However, the nature and rate of changes in the morphological properties of soils in the low arctic tundra during shrubification remain unknown. To study the impact of new...

Due to its insulating and draining role, assessing ground vegetation cover properties is important for high-resolution hydrological modeling of permafrost regions. In this study, morphological and effective hydraulic properties of Western Siberian Lowland ground vegetation samples (lichens, Sphagnum mosses, peat) are numerically studied based on to...

Thawing of frozen organic and mineral soils and liberation of organic carbon (OC), macro-and micro-nutrients and trace elements from pore ice in high latitude regions represent a potentially important but poorly quantified retroactive linkage to climate warming. This is especially true for permafrost peatlands, occupying a sizable proportion of all...

Over the past century, substantial changes in land use have taken place in the boreal zone of northern Eurasia. The consequences of these large-scale changes for the ecosystems of Europe have been well studied; however, they have not been addressed for the large expanses of Russia. We conducted a retrospective analysis of the landscape dynamics of...

Extensive studies have been performed on wildfire impact on terrestrial and aquatic ecosystems in the taiga biome, however consequences of wildfires in the tundra biome remain poorly understood. In such a biome, permafrost peatlands occupy a sizable territory in the Northern Hemisphere and present an extensive and highly vulnerable storage of organ...

Two multinucleate amoebae species, nowadays belonging to the genus Thecochaos, were never seen alive since 1913. Stained preparations deposited with the British Museum of Natural History (London) by E. Penard remain the only material proof of the existence of these organisms. We recently found an amoeba, identified as Thecochaos fibrillosum, in the...

To better understand freezing - thawing cycles operating in peat soils of permafrost landscapes, we experimentally modelled bi-directional freezing and thawing of peat collected from a discontinuous permafrost zone in western Siberia. We measured translocation of microorganisms and changes in porewater chemistry (pH, UV absorbance, dissolved organi...

The hydraulic properties of ground vegetation cover are important for high resolution hydrological modeling of permafrost regions, due to its insulating and draining role. In this study, the morphological and effective hydraulic properties of Western Siberian Lowland ground vegetation samples (lichens, Sphagnum mosses, peat) are numerically assesse...

The hydraulic properties of ground vegetation cover are important for high resolution hydrological modeling of permafrost regions, due to its insulating and draining role. In this study, the morphological and effective hydraulic properties of Western Siberian Lowland ground vegetation samples (lichens, Sphagnum mosses, peat) are numerically assesse...

The hydraulic properties of ground vegetation cover are important for high resolution hydrological modeling of permafrost regions, due to its insulating and draining role. In this study, the morphological and effective hydraulic properties of Western Siberian Lowland ground vegetation samples (lichens, Sphagnum mosses, peat) are numerically assesse...

Sphagnum moss, lichen and peat are widely present in arctic regions, covering millions of km² in permafrost-dominated regions. This multi-component low vegetation strata plays a key role in surfaces fluxes in these areas, as they are the most widespread interface between the atmosphere and the geosphere. Therefore, characterizing their transfer pro...

The fate of organic carbon (OC), nutrients and metals accumulated in thawing permafrost ice is at the forefront of environmental studies in the Arctic. In contrast to a fairly good understanding of the chemical nature of dissolved OC (DOC) and metals in surface Arctic waters, the speciation and colloidal status of solutes accommodated in the disper...

A middle-taiga iron-illuvial podzol (Glossic Endogleyic Albic Podzol) was studied on an ancient eolian dune in the Bol’shoi Yugan River basin (the Ob’ River tributary, Surgut region), near the large-scale archaeological research site. The radiocarbon age of 31 charcoals was determined, and 8 variants of the location of charcoal-containing soil zone...

This study investigated levels and sources of pollution and potential health risks associated with potentially toxic elements (PTEs) and polycyclic aromatic hydrocarbons (PAHs) in urban street dust collected from Tyumen city, a large transport centre with one of the highest motorization rates in Russia. Twenty street dust samples were collected fro...

Проведены исследования среднетаежного подзола иллювиально-железистого (Albic Podzol) на древней дюне в бассейне р. Большой Юган (приток Оби, Сургутское Приобье), вблизи участка проведения масштабных археологических работ. Определен радиоуглеродный возраст 31 морфона с древесными углями и выделено 8 вариантов расположения углистых морфонов относител...

На основе материалов экспедиционных исследований и данных дистанционного зондирования проведен анализ ландшафтного разнообразия тундровой территории Пур-Тазовского междуречья. Для микроландшафтов изучаемого региона приведены описания видового состава растительного покрова и рельефа поверхности, определено проективное покрытие видов растений, дана х...

Numerous experiments with nanoparticles have recently led to a better understanding of the migration of colloids and larger particles in soils. However, it remains unclear how colloidal particles migrate in soil horizons without macropores, and whether they can move with the fl ow of capillary water. In this article, we tested the hypothesis that c...

The article describes research and teaching activity of Denis Alexandrovich Gavrilov, Candidate of Biological Sciences, senior researcher with Soil Genesis Laboratory of the Institute of Soil Science and Agrochemistry of the Siberian Branch of the Russian Academy of Sciences, who died suddenly died young on August 26, 2021. He was also and enthusia...

Based on the data of the plant macrofossil and palynological composition of the peat deposits, the evolution and current state of polygonal peatlands were analyzed at the southern limit of continuous permafrost in the Pur-Taz interfluve. Paleoreconstruction shows that peat accumulation began in the Early Holocene, about 9814 cal. year BP, in the La...

To better understand freezing - thawing cycles operating in peat soils of permafrost landscapes, we experimentally modelled bi-directional freezing and thawing of the three sections of 90-cm long peat core collected from a discontinuous permafrost zone in western Siberia. We measured translocation of microorganisms and changes in porewater chemistr...

The landscape diversity of the tundra area in the Pur–Taz interfluvial region are analyzed using field and remote sensing data. For each land unit (microlandscape), botanical, microrelief, and soil descriptions are produced, projective covers of plant species are estimated, and seasonal soil thawing depths are defined. Additionally, the water table...

The soils of Chernevaya taiga (tallgrass fir-aspen hemiboreal rainforest) have high fertility in comparison with oligotrophic analogs formed in boreal taiga. We have studied humic acids isolated from the soils of Chernevaya and oligotrophic taiga in the Novosibirsk, Tomsk, Kemerovo and the Altai regions of Russia and for the first time the structur...

The concentrations of 15 individual PAHs in 93 peat cores have been determined by using high-performance liquid chromatography methods. In the profile the qualitative and quantitative composition of PAHs was non-uniform estimated in a wide range: from 112 to 3673 ng/g with mean 1214 ± 794 ng/g. Among 15 identified individual PAHs, the main contribu...

The proposed research is devoted to the effects of the urbanization on the soil cover through the assessment of common organic and inorganic pollutants as well as anthropogenic microartifacts (MAs) over 20 sites characterizing different land use areas within the city of Tyumen, Russia. The analytical methods included measurements of physical–chemic...

Permafrost peatlands, containing a sizable amount of soil organic carbon (OC), play a pivotal role in soil (peat) OC transformation into soluble and volatile forms and greatly contribute to overall natural CO2 and CH4 emissions to the atmosphere under ongoing permafrost thaw and soil OC degradation. Peat microorganisms are largely responsible for t...

Western Siberia lowlands vegetation cover consists of a complex patchwork of bryophytes (mosses s.l.), lichens (symbiotic association of heterotrophic Fungus and autotrophic Algae) and underlying peat (Volkova et al., 2018). This vegetation cover is the main interface between permafrost driven soil dynamics and the atmosphere. The energetic transfe...

Ecosystems of the permafrost zone with high biological productivity are accustomed to sites where geomorphological processes are intensively occurring and rejuvenate the mineral substrate. We have studied the alluvial cone of the gully at the point of its exit from the second above-floodplain terrace of the Pur River to the first terrace, where it...

The activities of ancient population strongly affected the development of landscapes and soils in Western Siberia during the late Holocene. It should be noted that studies devoted to the processes of natural and anthropogenic evolution within this vast territory are extremely irregular. Thus, the significant proportion of the materials on the dynam...

50 days' free access to the article: https://authors.elsevier.com/c/1cspbB8ccqtR4 Permafrost thaw in continental lowlands produces large number of thermokarst (thaw) lakes, which act as a major regulator of carbon (C) storage in sediments and C emission in the atmosphere. Here we studied thaw lakes of the NE European permafrost peatlands - shallow...

The majority of organic carbon (OC), nutrients, and dissolved trace elements in soil porewaters are present in the form of colloids which determine element transport, bioavailability, and overall impact on ecosystems. Climate warming and permafrost thaw in high latitudes will primarily affect the soil liquid phase thereby modifying delivery of coll...

The physical and chemical consequences of massive ground ice (wedges) melt upon permafrost thaw is one of the central issues of environmental research linked to climate warming in the Arctic. Little is known about the chemical properties of dispersed ground ice abundant throughout permafrost peatlands that can easily melt with increasing active lay...

Отчёт о небольшой полевой работе в Шорском национальном парке (Кемеровская область, Россия)