## 1 Introduction  
Currently, the entire agri-food system, from farm to fork, is responsible for about 37% of the overall human global greenhouse gases emissions [1]. These estimates include farm production, food processing, indirect emissions from deforestation and food waste. However, the single farm production component still counts for about 16-27% of the total emissions. Recently, a growing interest was shown in carbon sequestration by land, particularly in relation to the forthcoming challenges imposed by the need to reach carbon neutrality by about the middle of the century [2, 3]. Soils are the most important component of the biosphere and provide food security for mankind. They also provide regulatory ecosystem services, including the sequestration of atmospheric carbon, thereby contributing to climate regulation at the global and regional levels. Over the past two centuries, global losses of organic carbon in soils were estimated at 8%, as a result of land conversion and inefficient land-use practices alone. Intensive tillage for crop production leads to an increase in the amount of carbon dioxide released into the atmosphere, which exacerbates the greenhouse effect and global warming. Carbon dioxide emissions in more than 123 million hectares of agricultural land in Russia emit 290 million tons per year due to plowing. Russian arable land lost about 2.6 GIC (20%) from its top 0.3 m layer and 3.6 Gtc (16%) from its 0-1 m layer [4]. In general, there is significant potential to improve agronomic practices to decrease greenhouse gas emissions from crops and to improve cropland management to sequester additional soil carbon [5]. This can be achieved by implementing practices of conservation agriculture. These are based on the following practices: no till to minimize the impact on soils, constant covering of soil with crop residues and cover crops, as well as extensive use of biological methods, namely humic substances, entomophages, bees, bacterial and fungal products, etc. Such practices can be implemented on all types of soils, in all climatic conditions, regardless of the size of farms and agricultural practices [4]. At the same time, climate variability can determine a source of carbon emissions to the atmosphere and undermine the carbon sequestration potential of agricultural soil [6]. Even though the soil cover of the Russian Federation plays an important role in the global carbon cycle, the main components of the carbon cycle are still poorly investigated and require modern assessment for individual zones and regions of the Russian Federation [4]. Central Russia is the most important region of Russia's grain production. According to the Ministry of Agriculture in the Russian Federation, the Central Federal District accounts for 16.7% of total sown areas under grains and leguminous plants of Russia and 26% of the gross yield. Barley is second in importance after the wheat crop, which accounts for 19.7% of gross agricultural production [7]. According to existing climate predictions [1] over the next 50 years, the temperature increase in Central Russia will be in the range of 1-1.5 degrees in the case of an optimistic forecast (RCP 2.0) and 2-3 degrees in the case of a pessimistic forecast (RCP 8.5). Rainfall will increase by 10-25 mm per year, according to the two RCP scenarios, respectively. Thus, Central Russia even in case of a pessimistic forecast, will remain in a favorable zone (medium and good) for cereal cultivation and new intensive cultivated land will become available [8]. Thus, it is important to obtain more information on cropping systems in relation to climatic conditions, particularly since the European part of Central Russia shows a pronounced climate gradient from North to South becoming progressively drier and hotter. The static chamber method is the most common method in Russia for CO\({}_{2}\) flux assessment, so only soil respiration is measured directly, while NEE is assessed by NPP direct estimation [9].