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.

The paper presents a new monitoring station DIAMIS for continuous precisious observations of atmospheric carbon dioxide (CO2) and methane (CH4) mole fractions over the Yenisei Gulf, on the southwestern coast of the Taimyr Peninsula at the edge of the Dikson settlement. Here, we summarize technical details of the instrumental setup, give an overview of calibration and data processing algorithms, describe local environments of the study area, and analyze the seasonal footprint of the measurement station. Based on the observations in September 2018–February 2020, a comparative analysis of the atmospheric CO2 and CH4 annual variations in the polar belt (DIAMIS) and middle-taiga subzone (ZOTTO observatory) of near-Yenisei Siberia is presented.

Soil CO2 emission is one of the most important components of the global carbon cycle. This study analyzes the seasonal dynamics of soil emission for various land cover types in the middle taiga subzone of central Siberia during five growing seasons. It is shown that, throughout a vast area covered by pine forests and their derivatives formed on sandy soils, seasonal CO2 emission values are determined primarily by the moisture conditions and only secondarily by the temperature regime and ecosystem type. The effect of the forest type is manifested only under the most favorable moisture conditions. A new approach is proposed: divide the growing season into dry and moist periods depending on the threshold soil moisture for areas with different vegetation types.

A crucial issue in atmospheric studies on greenhouse gas content involves assessing the representativeness (footprint) having influence on their concentrations measured by tall towers. In this study, the Stochastic Time-Inverted Lagrangian Transport (STILT) model was used to estimate seasonal cumulative footprint climatology for greenhouse gases measurements obtained on the 301-meter-high Zotino Tall Tower Observation Facility (ZOTTO) for the growing seasons (May-September) from 2008 to 2012 (with the exception of 2011). Results showed that the ZOTTO seasonal concentration cumulative footprint climatology for four years reached 6.9×106 km2 and the 75% cumulative footprints varied from 1.9 to 2.3×106 km2. For the same period, the Russian Land Cover map based on MODIS data for 2014 was used to estimate the impact of land cover surrounding the ZOTTO tower on concentration measurements. The analysis showed that in the 75% seasonal cumulative footprint the largest area is occupied by bogs, followed (in decreasing order) by larch, mixed, light-coniferous evergreen forests, grassland, and by other classes. Furthermore, analysis of the contributions from individual cells making up a footprint showed that the largest influence on formation of greenhouse gas concentrations as recorded by ZOTTO comes from the types of vegetation growing in the immediate vicinity of the tall tower, namely bogs, mixed forests, and light and dark coniferous forest stands.