Centre for Isotope Bio-geochemistry

Scientific results:

1. The estimation of carbon sequestered over the last 20 years in the soils of Russia has been conducted. The rates of carbon sequestration during post-agricultural soil restoration in the territory of the Asian and European parts of Russia were analyzed, with consideration of the climate factors.
2. Organic carbon stocks in Russian soils, particularly in soils of agricultural areas, were regionalized to create predictive models of carbon sequestration on the scale of Russia and to analyse the distribution of carbon stocks within large ecological zones. Databases and GIS materials on regional land use were created to refine the available soil carbon stock models, their mapping and forecasting of carbon stock dynamics on arable and abandoned lands.
3. Approaches of granulometric, densimetric, biokinetic, and thermal fractionation techniques and their results to estimate SOM pools under contrasting land use types were analyzed.
4. Based on the use of δ13C and δ15N to estimate the relative turnover of organic C and total N in natural soils, it is found that N turnover is twice as fast as C turnover, and the main factors controlling SOM turnover are mean annual temperature and litter quality (C/N ratio in soil). The fastest C turnover is characteristic of evergreen forests, and the lowest for mixed and coniferous forests. The applicability of this approach to a wide range of studies of natural biocenoses in which SOC and total nitrogen contents are measured and δ13C and δ15N values was determined.
5. The effect of natural fires on the stability of soil organic matter was evaluated. It is revealed that wildfires lead to a decrease in the share of labile pool due to the primary oxidation and losses in the form of CO2 of the least stable organic compounds and dehydration reactions of aliphatic structures. At the same time, pyrogenic increase of labile pool is possible because of depolymerisation of complex organic molecules. Cyclisation and condensation reactions lead to an increase in the share of thermally stable organic matter in post-pyrogenic soils.

Organizational and infrastructural changes:

Centre for Isotope Biogeochemistry:

Isotope mass spectrometer isoprime precisION with vario ISOTOPE cube elemental analyser and headspace gas analyser isoFLOW module;

G2201-I intracavity isotope attenuation spectrometer;

Elemental analyser vario PYRO cube.

Education and personnel occupational retraining:

The Master's programme in the direction 06.04.01 Biology ‘Global Change and Carbon Regulation’ was developed and implemented from 2022.

The educational programme includes a wide range of disciplines on theoretical and practical issues of measuring climatically active gases, methods of carbon balance monitoring, approaches to carbon footprint assessment using life cycle assessment techniques, ecology of forest production, analysis of the current state of the climate and long-term scientific-based forecasting of its state.

Cooperation:

Institute of Physico-Chemical and Biological Problems of Soil Science RAS

Siberian Institute of Plant Physiology and Biochemistry SB RAS

RASTAM-Ecology Limited Liability Company