Наблюдаемый рост температуры, вызванный увеличением концентраций климатически активных (парниковых) газов в атмосфере, в первую очередь диоксида углерода (CO2) и метана (CH4), может быть причиной прогнозируемого высвобождения углерода, аккумулированного за тысячелетия на обширных территориях северных широт. Масштабы и длительность ожидаемого эффекта остаются открытым вопросом, что обусловлено спорадичностью количественных оценок потоков углерода. В работе отражены текущий статус, направления и основные результаты многолетних инструментальных исследований потоков углерода в экосистемах подзоны средней тайги Центральной Сибири, на базе Средне-Енисейского стационара Института леса им. В. Н. Сукачева СО РАН (обсерватории ZOTTO). Представлена динамика концентрации СО2и CH4в атмосфере с 2009 по 2020 г. Приведены данные чистого экосистемного обмена СО2для лесоболотных комп­лексов, свидетельствующие, что они выступают поглотителем (стоком) СО2атмосферы. Для репрезентативных экосистем дана оценка почвенных эмиссионных потоков СО2и сезонный ход фотосинтетической ассимиляции углерода доминантами подчиненного яруса растительности. Выявлены закономерности поведения растворенных форм углерода в водах ручьев, дренирующих олиготрофный и эвтрофный болотные массивы в районе исследований, представлены показатели эмиссии СО2с водной поверхности. The observed increase in temperature, caused by increasing concentrations of climate-active (greenhouse) gases in the atmosphere, primarily carbon dioxide (CO2) and methane (CH4), may be responsible for the projected release of carbon accumulated over millennia in large areas of northern latitudes. The scale and duration of the expected effect remains an open question, due to the sporadic nature of quantitative estimates of carbon flows. The work reflects the current status, directions and main results of long-term instrumental studies of carbon flows in the ecosystems of the middle taiga subzone of Central Siberia, on the basis of the Middle Yenisei experimental station of V. N. Sukachev Institute of Forest, Siberian Branch of the Russian Academy of Sciences (ZOTTO observatory). The dynamics of CO2and CH4concentrations in the atmosphere from 2009 to 2020 are presented. The values of net ecosystem exchange of CO2for forest-swamp complexes are given, indicating that they act as a sink (sink) of atmospheric CO2. For representative ecosystems, an assessment of soil CO2emission fluxes and the seasonal variation in the values of photosynthetic carbon assimilation by dominants of the subordinate vegetation layer are presented. The patterns of behavior of dissolved forms of carbon in the waters of streams draining oligotrophic and eutrophic swamps in the study area were revealed, and the values of CO2emission from the water surface were presented.

An understanding of how boreal forest composition responds to global environmental changes is an important challenge to predicting the future global carbon balance. Boreal forests are the most significant sink for atmospheric carbon dioxide; however, their sequestration capacity is highly sensitive to ongoing climate changes. The combination of the hydrothermal conditions of a territory strongly regulates its biogeochemical processes. The carbon fluxes in boreal forests are strongly mediated by the ground vegetation cover, composed of mosses (mesic) and lichens (xeric). Despite the concurrence of xeric and mesic vegetation types, their responses to climate variations varies significantly. Soil emission is an informative indicator of ecosystem functioning. In this study, we focused on the soil CO2 dynamics during frost-free seasons with different precipitation regimes in the xeric and mesic boreal ecosystems of Central Siberia. Seasonal measurements of soil CO2 emissions were conducted during frost-free seasons using the dynamic chamber method. Our findings reveal that the precipitation regimes of each year may control the seasonal soil emission dynamics. The soil moisture is the most important driver of emissions growth in the water-limited lichen pine forest (R2adj. = 18%). The soil temperature plays the largest role in the feather moss pine forest during the dry (R2adj. = 31%) seasons, and in the lichen pine forest during the wet (R2adj. = 41%) seasons. The cumulative efflux for the xeric and mesic sites is mostly related to the hydrothermal conditions, and not to the differences in ground vegetation cover. During the dry seasons, on average, the soil CO2 emissions are 45% lower than during the wet seasons for both sites. These findings emphasize the need for estimating and including the hydrothermal characteristics of the growing season for detailed emission assessments.

Количественные оценки баланса углерода ландшафтов суши и особенно криолитозоны, где наблюдаются наиболее значимые тренды потепления, требуют учета экспорта терригенного углерода за их пределы с латеральным стоком. В работе представлены результаты многолетнего круглогодичного мониторинга внутрисезонных и межгодовых флуктуаций концентраций растворенного органического (РОУ) и неорганического (РНУ) углерода в гидрографической сети Среднесибирского плоскогорья, осуществляемого на базе Эвенкийского стационара Института леса им. В. Н. Сукачева СО РАН (п. Тура). Исследования проводились на более чем 100 водотоках разного порядка в среднем течении р. Нижняя Тунгуска (62–66° с. ш., 96–102° в. д.) на основе регулярного измерения концентраций всех форм углерода, а также квазинепрерывного мониторинга физико-химических параметров водотоков с помощью автоматических логгеров-регистраторов. Показано, что основными лимитирующими факторами латерального стока углерода в пределах Среднесибирского плоскогорья в настоящее время являются запасы потенциально мобилизуемого органического углерода в наземных ландшафтах и количество осадков в условиях резко континентального климата. Рост стока органического углерода прогнозируется в результате как оттаивания богатых Соргмерзлых толщ, так и повышения продуктивности растительного покрова, а неорганического углерода – вследствие повышения скоростей выветривания горных пород и секвестрации атмосферного СО2. Отрицательные прогнозы поведения РОУ связываются с увеличением глубины инфильтрации растворов с ростом сезонно-талого слоя почвы, что определяет сорбцию РОУ в почвенной толще и его микробиологическую деструкцию. Возрастание площадей и интенсивности пожаров в результате потепления климата определяет существенную трансформацию латерального стока углерода. При этом наблюдаемое сокращение стока рек в результате усиления пирогенного фактора будет определять общее снижение транспорта терригенного углерода из наземных ландшафтов. Quantitative assessments of the carbon balance of terrestrial landscapes and, specifically the permafrost zone, where the most significant warming trends are observed, require taking into account the export of terrigenous carbon beyond their boundaries with lateral flow. The paper presents the results of long-term monitoring of intraseasonal and interannual fluctuations in the concentrations of dissolved organic (DOC) and inorganic (DIC) carbon in the hydrographic network of the Central Siberian Plateau, carried out on the basis of the Evenkian field station of the V. N. Sukachev Institute of Forest, Siberian Branch, Russian Academy of Sciences (Tura settlement). Research is being carried out on more than 100 streams and rivers of various orders in the middle reaches of the Lower Tunguska River (62–66°N, 96–102°E) based on regular measurements of the concentrations of all forms of carbon, as well as quasi-continuous monitoring of the physical and chemical parameters using specific sensors and automatic loggers. It has been shown that the main limiting factors of lateral carbon flux within the Central Siberian Plateau at present are: 1) stocks of potentially mobilizeable organic carbon in terrestrial landscapes and 2) amount of precipitation in a sharply continental climate. An increase in the DOC flux is predicted both as a result of thawing of C-rich frozen deposits and an increase in the productivity of plant cover, and inorganic carbon – as a result of increased rates of silicate rock weathering and sequestration of atmospheric CO2. Negative predictions of DOC behaviour are associated with an increase in the depth of infiltration of solutes with an increase in the seasonally thawed soil layer, which determines the sorption of DOC in the soil column and its microbiological destruction. An increase in the area and intensity of fires as a result of climate warming determines a significant transformation of the lateral carbon flux. At the same time, the observed reduction in river flow as a result of an increase in the pyrogenic factor will determine the overall decrease in the transport of terrigenous carbon from terrestrial landscapes.

Происходящие изменения климата в бореальной зоне оказывают влияние на углероддепонирующую способность лесных экосистем. Экологические условия и таксономическое разнообразие растительного покрова биогеоценозов определяют актуальность исследования фракционного состава их фитомассы и пигментного комплекса в устойчивости и регуляции активности фотосинтетического аппарата. Живой напочвенный покров, как правило, недооценивается или исключается при оценках лесной фитомассы в связи с отсутствием стандартных уравнений. В настоящем исследовании для смешанного леса средней тайги проведена оценка запаса надземной фитомассы и разработан набор аллометрических уравнений у широко распространённых видов, произрастающих в смешанном лесу средней тайги: линнея северная ( Linnaea borealis L.), багульник болотный ( Ledum palustre L.), черника обыкновенная ( Vaccinium myrtillus L.), голубика обыкновенная ( V. uliginosum L.), брусника обыкновенная ( V. vitis-idaea L.). Наибольшей встречаемостью в лесном биогеоценозе (60 %) характеризуется брусника . Доминантфом яруса выступает черника обыкновенная, запас которой составляет 21.2 ± 52.8 г/м2. Соотношение среднего запаса листовой фитомассы к древесной колеблется от 0.08 ± 0.17 для черники обыкновенной до 0.73 ± 1.04 для брусники. Определены индекс листовой поверхности и концентрация основных фотосинтетических пигментов у преобладающих видов в кустарничковом ярусе растительности. Индекс варьировал от 0.027 ± 0.062 м2/м2 для черники обыкновенной до 0.097 ± 0.077 м2/м2 для багульника болотного. В смешанном биогеоценозе среднетаежной зоны наибольшее количество хлорофиллов и каротиноидов обнаружено в листьях голубики, а наименьшее - брусники. Фотосинтетический аппарат изучаемых видов характеризуется довольно стабильным накоплением фотосинтетических пигментов, относящихся к светособирающему комплексу. The ongoing climate changes in the boreal zone affect carbon sequestration capacity of forest ecosystems. Thus, the environmental conditions and taxonomic diversity of the plant cover of ecosystems determine the relevance of studying the fractional composition of their phytomass and pigment complex in the stability and regulation of the activity of the photosynthetic apparatus. Living ground cover is typically underestimated or excluded when estimating forest phytomass due to the lack of standard equations. In this study, we assessed the stock of aboveground phytomass and developed a set of allometric equations for widespread species of living ground cover growing in the mixed forest of the middle taiga: Vaccinium vitis-idaea L., Ledum palustre L., Vaccinium uliginosum L., Vaccinium myrtillus L., Linnaea borealis L. The highest percentage of occurrence in the forest ecosystems (60 %) is characterized by the species V. vitis-idaea . The dominant species is V. myrtillus , the reserve of which is 21.2 ± 52.8 g/m2. The ratio of the average supply of leaf phytomass to wood phytomass ranged from 0.08 ± 0.17 for V. myrtillus to 0.73 ± 1.04 for V. vitis-idaea . Leaf area index and photosynthetic pigments for the study objects were also determined. The index varied from от 0.027 ± 0.062 м2 м-2 for V. myrtillus to 0.097 ± 0.077 м2 м-2 for L. palustre . In the mixed forest of the middle taiga zone, the largest amount of chlorophylls and carotenoids was found in the leaves of V. uliginosum , and the smallest - in V. vitis-idaea . The photosynthetic apparatus of the studied species is characterized by a fairly stable accumulation of photosynthetic pigments belonging to the light-harvesting complex.

Lichens and other terrestrial photosynthetic unicellular organisms of the planet consume nearly 14.3 billion tons of atmospheric CO2. Due to climate change, such important components of the forest ground cover as lichens are very vulnerable. This study evaluates the photosynthetic activity in widespread lichens by measuring the indices of net photosynthesis, dark respiration, and prompt fluorescence. Hence, cryptogams of pine forests in Central Siberia near the Zotino tall tower observatory (ZOTTO) are characterized as highly active. Cladonia stellaris (Opiz.) Brodo and Cladonia rangiferina (L.) are the main representatives of ground cover species. The purpose of this study was to determine the photosynthetic activity in dominant species of ground cover lichens during a growing season. We found the seasonal dynamics of photosynthesis with the lowest values being observed in June, and the highest ones in August. Dark respiration peaks in June and is the lowest in September. Fluorescence values are within the range of 6.7 ± 0.3. The species under study that grow on podzol soils in pine forests show fast kinetic activation.

Потенциальное воздействие парниковых газов на глобальный энергетический бюджет и будущий климат обуславливает необходимость количественной оценки наземных источников и поглотителей углерода [3, 5]. Лишайники, создавая сложную синузиальную структуру в экосистемах северных широт являются доминантами и со доминантами в местообитаниях с экстремальными экологическими условиями [2], потребляя около 14.3 млрд тонн атмосферного CO2 [4]. В данном исследовании дается эколого-физиологическая характеристика лишайников путем измерения показателей чистого фотосинтеза, темнового дыхания, а также количественного определения фотосинтетических пигментов. Район исследования расположен на территории Средней Сибири в зоне охвата станции высотной мачты ZOTTO (60 ° N, 89 ° E). Объекты исследования - доминанты мохово-лишайникового яруса: Cladonia stellaris O., Cladonia rangiferina L., Cetraria islandica L.. Интенсивность фотоасссимиляции CO2 определяли на инфракрасном газоанализаторе Walz GFS-3000 (Heinz Walz GmbH, Effeltrich, Германия). Определение содержания фотосинтетических пигментов производилось согласно методике Барнеса [1] с дальнейшим анализом спектров поглощения спектрофотометра Varian Cary 100 (Agilent Corp., США). Согласно результатам двухфакторного дисперсионного анализа статистически значимой разницы в значениях фотосинтеза между изучаемыми видами лишайников не выявлено (р= 0.9411), однако наблюдается сезонная динамика (р=0.0001) на протяжении всего периода измерений. В среднем за сезон интенсивность фотоассимиляции (А, мкмоль м-2 с-1) составляла для изучаемых видов лишайников 1.8±0.072 мкмоль м-2 с-1. Наибольшая вариация значений характерна виду C. stellaris, от 0.11 ±0.02 мкмоль м-2 с-1 в июне до 3.58 ±0.07 мкмоль м-2 с-1. Исследование выполнено при финансовой поддержке важнейшего инновационного проекта общегосударственного значения: «Разработка системы наземного и дистанционного мониторинга пулов углерода и потоков парниковых газов на территории Российской Федерации, создания системы учета данных о потоках климатически активных веществ и бюджете углерода в лесах и других наземных экологических системах» (№123030300031-6). Натурные наблюдения и обработка исходных данных выполнены при поддержке Российской академии наук в рамках государственного задания (№FWES-2021-0008 и № FWES-2021-0041) Института леса им. В. Н. Сукачева СО РАН.

The peatlands in the northern hemisphere cover just 3% of the global landmass but their impact to the carbon emission is huge. The current climate changes exert influence on these ecosystems by changing water supply, temperature regime, plant growing activity and others. Nowadays studies predicted the important role of the northern bogs and peatlands as an additional source of atmospheric CO 2 . In our study we estimated how microrelief and microclimatic conditions can control the CO 2 emission from the bog area. We compared also the waterlogged bog conditions and forest ecosystem to find out the main drivers of soil emission dynamics during the summer season. The rate of CO 2 emission varies widely within bog area depending on the microrelief of the area: hollow – 0.74±0.03, ridge – 1.69±0.08 kg CO 2 m –2 . The comparative analysis versus the forest area showed that the upland parts of the bog area are not inferior to the forest area in terms of the emission rate. Moisture conditions determined the CO 2 efflux for the hollow site ( r =0.49, p<0.05 ) and forested area ( r =0.39, p<0.05 ). The temperature impact is observed for all sites and it is significant throughout the season.

The current climate changes exert influence on these ecosystems by changing water supply, temperature regime, plant growing activity and others. Nowadays studies predicted the important role of the northern bogs and peatlands as an additional source of atmospheric CO2. The research area was located in the Krasnoyarsk region, Russia (60° 48’ N, 89° 22’ E) close to the International research station – ZOTTO (http://www.zottoproject.org). In our study we estimated how microrelief and microclimatic conditions can control the CO2 emission from the bog and forested areas. We compared also the waterlogged bog conditions and forest ecosystem to find out the main drivers of soil emission dynamics during the summer season. The rate of CO2 emission varies widely within the bog area depending on the microrelief of the area: hollow site – 0.74 ±0.03, ridge site – 1.69 ±0.08 kg CO2 m-2. Comparative analysis with the forest area showed that the upland parts of the bog area are not inferior to the forest area in terms of the CO2 emission rate. Moisture conditions determined the CO2 efflux for the hollow site (r=0.49, p<0.05) and forested area (r=0.39, p<0.05). The temperature impact is observed for all sites and it is significant throughout the season. Thus, within a single bog area micrometeorological characteristics of the underline surface during the season significantly control the CO2 emission rates. The research was funded by RFBR, Krasnoyarsk Territory and Krasnoyarsk Regional Fund of Science, project number 20-44-243003.

In northern palsa mires stable isotopes of C and N of peat organic matter (OM) and O and H of segregated ice may serve as an important conduit of information about variability of environment conditions and OM turnover in the past millennia and modern time. In our study we applied the multi-isotopic record to distinguish variation in the development of palsa peatlands located in forest-tundra ecotone of Central Siberia. The study sites are located in vicinity of Igarka settlement (67o31’ N, 86o38’E) within the area underlain discontinuous permafrost. The peat cores were obtained in the central intact parts of perennial frost hummocks located in basins of the Gravijka and Little Gravijka rivers (depth 8.6 and 2.7 m, respectively). Thawed and frozen peat samples were collected at 1.0-5.0 cm step depending on the amount of peat and ice material. Peat (solid) samples were analyzed for C and N content and stable isotopic composition (δ13C and δ15N) by TOC Macro cube (Elementar, Germany) paralleled with Isoprime 100 IRMS (UK). Water stable isotope composition (δ18O and δ2H) of segregated ice samples (melted) were obtained by Picarro L-2120-i (Picarro Inc. USA). The age of studied peatlands ranged between about 6200 cal yr BP (Gravijka site) and 4300 cal yr BP (Little Gravijka site). Meanwhile, there was the large loss of organic matter in the upper active layer of peat deposits as at 15 cm depth the age of OM was ca. 1800 cal yr BP. These findings suggest OM removal during wildfires and likely erosion processes following fires, and specific isotopic composition mirrors an enhanced OM decomposition in active layer. The large variations in composition of analyzed stable isotopes in frozen peat core captured the changes occurred during the past epochs in an input of OM (changes in vegetation and productivity), peat decomposition rates, nitrogen cycle perturbations as well as hydrothermal regimes and permafrost processes like aggradation (e.g. hummock uplift and cryoturbation) and degradation (e.g. hummock collapse, shifts from minerotrophic to ombrotrophic conditions and vice versa). This work was supported by the Russian Science Foundation, project № 20-17-00043.

Bryophytes and lichens usually dominate the ground floor layer of boreal forests and tundra, and contribute up to 50% of ecosystem gross CO2 exchange (Bisbee et al. 2001; Goulden & Crill 1997). While Sphagnum spp. are the most important contributors in wetland C uptake, feathermosses and lichens play a significant role in drained habitats (Nilsson & Wardle 2005; O’Connell et al. 2003; Bjerke et al. 2013). Given their important ecological roles in such widespread biomes, it is surprising that still a few studies have attempted to understand the intrinsic factors that control moss-lichen cover carbon exchange dynamics specifically under ongoing climate change in high latitudes. The aim of this work was to determine photoassimilation activity the widespread species of moss-lichen stratum during the growing season. The study has been conducted in Central Siberia near Zotino tall tower observatory (ZOTTO, 60 ° N, 89 ° E) in lichen- and feathermoss-dominated pine forests. The intensity of CO2 photoassimilation of ground vegetation dominants (Cladonia stellaris O., Cladonia rangiferina L., Cetraria islandica L., Pleurozium schreberi W. ex B., Hylocomium splendens H., Dicranum scoparium H.) was determined in situ by infrared gas analyzer Walz GFS-3000 (Heinz Walz GmbH, Effeltrich, Germany) during the most part of a growing season (from June to September). Bryophytes demonstrated more intense photosynthetic activity throughout the growing season. From June to September, among the studied moss species, the highest values of photoassimilation were observed for P. schreberi, and the lowest for H. splendens. The maximum values were recorded in August for all studied species and amounted to 4.36 ± 0.13 μmol / m2 / s, and the lowest values were recorded in June to 1.4± 0.08 μmol / m2 / s . Among lichens, C. stellaris was the most photosynthetically active, and C. rangiferina showed the least CO2 photoassimilation rates. Moss-lichen layer dominants maintained relatively high photoassimilation activity throughout the growing season. The research was funded by Krasnoyarsk Regional Fund of Science within the framework of the project № 2021 102007845 and RFBR, Krasnoyarsk Territory and Krasnoyarsk Regional Fund of Science, project number 44-243003.

There is the significant progress in recent decades in the quantification of terrigenous carbon release to the rivers of the Arctic Ocean basin and characterization of its chemical properties, origin and age (e.g. Amon et al., 2012, Holmes et al., 2012). As warming accelerates the thawing permafrost may potentially increase the release the ancient carbon (Wild et al., 2019, Estop-Aragonés et al., 2020). However, more detailed analysis is still needed particularly in regard of the age of carbon exported from the diverse landscapes of large Arctic rivers and its transformation during the transport to the Arctic ocean. In this study we analyzed D14C in dissolved organic carbon (DOC) and particulate organic carbon (POC) of the Yenisei River main channel and its major tributaries between 56oN and 68oN at freshet, summer and fall seasons. D14C was measured in Max Planck Institute for Biogeochemistry (Germany) by the accelerator mass spectrometry (AMS) system based on a 3MV Tandetron accelerator as described earlier (Steinhof et al., 2017). The oldest DOC in the Yenisei main stem was detected right after the Krasnoyarsk dam (56oN) and varied during a year without clear seasonal pattern in the range of the fraction of modern C (fMC) from 0.868 to 1.028. At freshet the fMC increased down stream up to 1.12 at 60oN and then remained relatively stable between 61o and 67.4oN (1.097±0.014). The major tributaries released DOC with fMC ranging from 1.0869 (Angara, 58oN) to 1.1046 (Kurejka (66.5oN), demonstrating more modern C with latitude. During the summer-fall season the Yenisei main channel and main Eastern tributaries contained older DOC (fMC = 0.968-1.054 and 0.949-1.045, respectively). The POC of the Yenisei River was sufficiently older (fMC = 0.83-0.92) than DOC at all seasons and showed similar latitudinal pattern, i.e. the youngest POC was detected near 60-61oN (fMC > 0.90). The D14C-POC values in analyzed tributaries were increasing with latitude at freshet (R2 = 0.53) and summer lowflow (R2 = 0.33), except the largest Eastern tributaries, demonstrating the slight opposite pattern. On the other hand, increasingly more ancient POC was releasing by permafrost-dominated Eastern tributaries with increasing basin size. In opposite, D14C-POC of Western tributaries showed increased input of more recently fixed carbon. Our findings provided new data on the formation of terrigenic carbon fluxes to the Arctic Ocean from one of the largest river basins in the Arctic. This study was supported by RFBR grants #18-05-60203-Arktika. The radiocarbon analyses were kindly supported by Max-Plank Institute for biogeochemistry (ZOTTO project).

The bog ecosystems of the northern regions, with low productivity, can accumulate large amounts of carbon due to the low rate of decomposition and respiration. However, it is expected that climate change will lead to an intensification of assimilation and respiratory activity. In this work we considered the emission activity of a raised bog during the growing season. We also analyzed the main environmental factors that could have a significant impact on the CO2 emission rates from the bog surface. In our study, we examined the seasonal dynamics of CO2 emission from the surface of a raised bog (ryam). The study of soil emission was carried out for three seasons (2018-2020) on sections of the bog area of different heights - ridges and hollows. Soil emission measurements were performed using an LI-8100A infrared gas analyzer (Li-cor Inc., Lincoln, USA). Temperature measurements measured at three depths - 5, 10, and 15 cm from the surface using a Soil Temperature Probe Type E (Omega, USA). A Theta Probe Model ML moisture meter (Delta T Devices Ltd., UK) was used to measure the volumetric moisture (5 cm from the surface). The bog water level was measured during the entire frost-free period using the HOBO Water level logger U20L-04 (Onset, USA). In terms of the temperature regime of soils, the studied areas also differ significantly from each other, demonstrating the big discrepancies in the more humid seasons of 2019 and 2020. The difference in temperature in these seasons was about 1.0 degrees C, while in the 2018 season with insufficient moisture, the difference was two times less 0.5 degrees C. The maximum emission fluxes of CO2 in the studied bog massif were recorded in the first half of August, and the lowest - from the middle of September. The highest emission rates were recorded in the 2019 season: CO2 fluxes from the bog surface averaged 4.17 +/- 4.55 mu mol CO2/m(2)/s per season. For all observation seasons, CO2 fluxes on ridges exceeded hollows by more than 60 % (p <= 0.05). The strongest dependence was observed between the CO2 emission rate and soil temperature, moreover, in the season with the amount of precipitation below the mean annual norm (http://www.meteo.ru) - 2018, the correlation is higher and the rcoefficient was 0.6 and 0.8 for the ridge and hollow sites, respectively (p <= 0.05). The dependence of CO2 emission on moisture conditions, on the contrary, is rather weak for two sites, and is often negative. Thus, based on the results obtained, it can be concluded that the emission flux from the surface of a raised bog during the snow-free period depends not only on the moisture conditions of a particular season, but also on the section of the bog area: the emission of CO2 from local elevations of the microrelief - ridges is much higher than from more watered areas - hollows. A significant response to moisture conditions was found only for the season with insufficient moisture and in an elevated section of the bog area - ridge site. The CO2 emission rate during the growing season is mainly determined by the temperature regime.

The lateral migration of dissolved carbon dioxide (CO2) with soil solutions to fresh water aquatic systems and in situ mineralization of soil-derived organic carbon (OC) often causes supersaturation of the inland waters with CO2. An evasion of excess CO2 from lake and stream surfaces to the atmosphere is important, but underestimated, pathway of carbon flux in the coupled terrestrial-aquatic carbon cycle. As a result, the loss of terrestrial OC as CO2 through the drainage networks remains poorly accounted in regional carbon budgets estimated on the basis of eddy covariance measurements. In this study we have made an attempt to quantify fluxes of dissolved CO2 (pCO2) and CO2 emissions (fCO2) in fluvial and lacustrine waterbodies located within the peat-bog dominated landscape of Western Siberia (ZOTTO area, 60oN, 89oE). For two consecutive years (2018-2019) we studied the seasonal and diurnal dynamics of pCO2 and fCO2 in several different order streams (1-4) and ponds within a peatbog. Dissolved pCO2 was measured by portable IRGA Vaisala GMP222 placed in PTFE membrane. Carbon dioxide emissions were analyzed using floating chamber equipped with same portable IRGA (Vaisala GMP222). Despite, the pCO2 values were highest in winter season (350-820 umol/l) we did not detect sizeable emissions from water surface in that period. The peaks of pCO2 in summer-fall season (up to 360 umol/l) occurred at stormflow regimes. The frost-free season emission of CO2 from stream surfaces ranged from 0.2 to 7.5 umol/m2/s and decreased with the order of stream. An averaged for the season CO2 evasion from the Razvilki stream (2nd order stream) was 4.9±1.3 umol/m2/s, which is comparable to the seasonal mean of soil CO2 emissions in the study area. However, in opposite to soil respiration, which maxima often corresponds to highest soil temperatures, peaks of CO2 outgassing occur at high flow regimes. The fCO2 values were correlated with discharge (r = 0.60, p<0.05) and DOC concentrations (r = 0.69, p<0.05). Aquatic C losses are still under analysis in terms of surface water area estimation.

The stocks of phyto(bio)mass of a ground vegetation cover consisting of dwarf shrubs, lichens, and feathermosses are estimated in pine forests of Central Siberia (ZOTTO). CO2 photoassimilation dynamics is analyzed for the dominant species of the moss-lichen layer throughout the growing season. In parallel, we assess the impact of abiotic environmental factors on the photoassimilation intensity.

In boreal forests, bryophytes and lichens usually dominate the ground floor layer and contribute up to 50% of ecosystem gross CO2 exchange (Bisbee et al. 2001; Goulden & Crill 1997). Sphagnum spp. are the most important contributors in wetland C uptake, and feathermosses and lichens play a significant role in well-drained sites (Nilsson & Wardle 2005; O’Connell et al. 2003; Jarle W. Bjerke et al. 2013). Given their important ecological roles in such a widespread biome, it is surprising that still a few studies have attempted to understand the intrinsic factors that control moss-lichen cover carbon dynamics specifically under ongoing climate change in high latitudes. The aim of this work was to determine the stocks of moss-lichen stratum and photoassimilation activity of its dominant species during the growing season. The study has been conducted in Central Siberia near Zotino tall tower observatory (ZOTTO, 60 ° N, 89 ° E) in lichen- and feathermoss-dominated pine forests. First, to assess the phyto (bio) mass stocks the grass-shrub and moss-lichen layers were sampled in 100 replicates in each type of forest from 20x25 cm subplots (S = 50 cm2). The intensity of CO2 photoassimilation was determined in situ by Walz GFS-3000 (Heinz Walz GmbH, Effeltrich, Germany) infrared gas analyzer. Photosynthetic activity of lichens and feathermosses was measured during the growing season of 2018 in June, July, August and September around the mid-day time. For every time point we also analyzed CO2 exchange dependence from temperature, photosynthetically active radiation (PAR) and CO2 concentration. The dominants of ground vegetation for the moss-lichen layer were Cladonia stellaris, Cladonia rangiferina, Cetraria islandica, Pleurozium schreberi, Hylocomium splendens, Aulacomnium palustre. The moss-lichen layer accounted for 78-96% of the total phytomass of ground floor in studied pine forests and comparable (486 g/m2) to the photosynthetic phytomass of the tree canopy (pine needles). During the growing season, carbon assimilation by the moss-lichen layer varied in a relatively narrow range: from 38 ± 4 to 42 ± 5 mgCO2 / m2 / hour for lichen C. stellaris and from 93 ± 11 to 99 ± 13 mgCO2 / m2 / hour for moss P. schreberi. Thus, moss-lichen layer dominants maintained high photoassimilation activity throughout the growing season. Temperature increased the intensity of CO2 assimilation and no inhibition was observed at maximum T used in our study (+40 ° C). There were no differences in the temperature dependence of CO2 photoassimilation between feathermosses and lichens. However, they differed in dependence from PAR. Mosses showed 2-fold larger response of CO2 assimilation intensity to increase of PAR comparatively to lichens. The rate of photosynthesis of both moss and lichen showed log growth with increasing CO2 levels up to 2000 ppm. Compensation poit was varying from 170 to 284 ppm. This study was supported by the Russian Foundation for Basic Research project № 18-05-60203 "Landscape and hydrobiological controls on the transport of terrigenic carbon to the Arctic Ocean".

The paper is devoted to the assessment of the prospects of implementing clean energy sources in Russia, where the current energy policy goal is to increase the role of renewable and clean energy sources. The research is based on data from the Krasnoyarsk Region as one of the largest territories but also as a representative model of Russia. The aim of the study is to identify where and which renewable energy source (solar, wind, hydro and nuclear) has the highest potential. The novelty of our research lies in its holistic nature: authors consider both geographical and technical potential for renewable energy sources development as well as prospective demand for such resources, while previous research is mostly focused on specific aspects of renewable energy development. We also consider the level of air pollution as an important factor for the development of renewable energy sources. The results of the study show that there is a strong potential for clean energy sources in the Krasnoyarsk Region. The resulting matrix identifies the potential of energy sources across all the municipal entities and also indicates whether the source of energy is primary or supplemental and where several sources may be implemented in cooperation.

Количество осадков или условия увлажнения территории являются основным лимитирующим фактором для всех биологических процессов в бореальных лесах [IPCC, 2001]. Почвенная эмиссия СО2 (Rs), как один из основных потоков углерода в экосистеме, существенно влияет на функциональную роль территории, меняя ее качественные характеристики из стока в дополнительный источник углерода [Davidson et al., 1998]. На сегодняшний день, большое число исследований указывают на то, что почвенная эмиссия СО2 в экосистемах, лимитированных поступлением воды, имеет импульсный ответ на поступление осадков [Yuste et al., 2003; Jarvis et al., 2007]. Влажность почвы может влиять на Rs нелинейно (параболически), ограничивая корневую и микробную активность в почве при низких уровнях влажности почвы и ограничивая коэффициент диффузии CO2 при высоких уровнях влажности почвы [Orchard and Cook, 1983; Maier et al., 2010]. Основное влияние условий увлажнения отмечается в течение вегетационного сезона, когда в наиболее активной фазе находятся все биогеохимические реакции [Yuste et al., 2003]. Сезонная динамика содержания воды в почве может варьироваться от года к году и влиять на значение Q10 [Davidson et al., 1998]. Было высказано предположение о том, что небольшое отклонение в Q10 может вызвать значительное смещение в оценке Rs [Xu и Qi, 2001]. Таким образом, применение Q10 в прогнозировании будущих потерь CO2 из почвы без учета годовых и сезонных колебаний определенных факторов (включая влажность почвы) может привести к значительным ошибкам. Кроме того, сезонная зависимость Rs от содержания воды в почве до сих пор плохо изучена, поскольку изменения температуры почвы и содержания воды часто коррелируют, а независимое влияние каждой переменной трудно обнаружить или интерпретировать [Davidson et al., 1998].