RuFlux: The Network of the Eddy Covariance Sites in Russia

Abstract

For the first time, the information is summarized on the history of establishment, the state of observations and the main scientific results on sites included in RuFlux, the Russian eddy covariance network for the monitoring of greenhouse gases (GHG). Eddy covariance technique provides estimates of GHG fluxes at the level of ecosystems. The long-term series of GHG fluxes (more than 190 site-years of observations) have been obtained. Up to the end of 2022, 86% of the sites of the RuFlux network are located in forests and wetlands, 77% of all sites are in the middle and southern taiga. Almost all undisturbed ecosystems in Russia are the sinks of CO2 from the atmosphere with a range of average annual estimates of net absorption from 80 to 240 g C m–2 yr–1. The GHG balance is determined by a complex of abiotic and biotic factors. The average long-term net CO2 absorption is higher in permafrost Siberian larch forests than in European spruce forests. When moving from west to east, the intensity of CO2 sink in the middle of summer increases, and the emission of CO2 in the middle of winter decreases sharply. Natural and anthropogenic disturbances lead to the transformation of the carbon balance by increasing the release of CO2 into the atmosphere. RuFlux network covers a wide range of types of ecosystems, but it is needed to organize more GHG sites in tundra, northern taiga, forest-steppe, steppe, and semi-deserts; in the ecosystems disturbed by humans (including fields) and in the ecosystems with successions caused by natural disturbances.