色控传媒soil scientists developed a new method for assessing soil fertility
The studies related to the simultaneous measurement of CO2 emissions from soils of different land use and its microbial properties are not carried out so often, and the results of such studies are largely contradictory. Therefore, to study the possible relationship between these indicators, 色控传媒soil scientists together with colleagues from the Institute of Chemical Physics and Technology of the Russian Academy of Sciences (Pushchino) analyzed the chernozem soils of the virgin steppe, broad-leaved forest, naked fallow and cities located in the forest-steppe zone of European Russia (Kursk region).
Transformation of natural ecosystems into arable land leads to a deterioration in the functioning of the soil microbial community and is expressed in a decrease in its amount and respiratory activity. Taking into account that at least half of the CO2 emissions from the soil surface to the atmosphere is ensured by the respiration of soil microorganisms (CO2 formation), and the transformation of terrestrial ecosystems is usually accompanied by a deterioration in the functioning of the soil microbial community (a decrease in biomass and inhibition of respiratory activity) and a decrease in the amount of available soil organic carbon, the soil scientists put forward a scientific hypothesis that there should be a certain interrelation between the emission of CO2 from the soil and its microbial properties.
“Considering that the 小袨2 emission from the soil is regulated by hydrothermal conditions (temperature, humidity), and its moisture is important for the soils of the steppe zone, the assessment of the microbial respiration of these soils during the growing season will reveal its interrelation with the emission flow of this gas,” says co-author of the article Kristina Ivashchenko from RUDN.
Every month from May to October, 色控传媒soil scientists were measuring measured in vivo the CO2 emission of the chernozem of unmown steppe, forest (oak grove), naked fallow and meadow (located in the city). Soil CO2 emissions were measured by a closed-chamber approach using an infrared gas analyzer. Immediately after measuring the emission activity of the soil, its samples were taken from the upper 10-centimeter layer, which were then delivered to the laboratory for measuring microbiological parameters. The carbon content of microbial biomass (CMIC) was analyzed using the method of substrate-induced respiration, which is based on the respiratory response of soil microorganisms to the introduction of one of the main metabolites of decomposition of plant litter — glucose. Microbial respiration (MR) of soil microorganisms was determined in soil samples without plant roots, which were removed by sifting.
CO2 emission from the soil surface (aboveground vegetation was previously cut) in different ecosystems for 6 months of observation ranged from 2.0 to 35.8 g of CO2 m-2 per day). It was highest in the steppe (23.8 g 小袨2 m-2 per day), lower in the forest and the city (15.0 and 15.3 g CO2 m-2 per day, respectively) and the lowest in naked fallow (3.7 g CO2 m-2 per day). It was shown that CO2 emission from the soil of the steppe, forest, and city was on average 4–6 times higher than that of naked fallow, where vegetation was removed by periodic plowing
The content of CMIC in the upper 10 cm soil layer in the studied ecosystems varied from 251 (naked fallow) to 1713 μg C g-1 (forest). It turned out that in the soil of each ecosystem studied during the growing season, the content of CMIC did not differ significantly. At the same time, CMIC content of soil in undisturbed ecosystems (forest, steppe) turned out to be 3-5 times higher on average than in disturbed ones (city, naked fallow).
The MR of soil of forest, steppe, fallow, and urban areas ranged from 0.28 (fallow) to 1.81 μg CO2 — C g-1 h-1 (forest). The MR of naked fallow and urban soils during the study period did not change; in the forest it was the highest in October, and in the steppe — in July and August. The MR in undisturbed ecosystems was 2–4 times higher than in disturbed ones (city, naked fallow).
The study demonstrated that 小袨2 emission from the soil surface in the studied ecosystems has a positive correlation with the CMIC content and MR of the upper 10-centimeter soil layer (r = 0.56 and 0.74, respectively). A regression analysis of the experimental data showed that CO2 emission from the surface of chernozem of different land use during the growing season was determined by the CMIC content by 52% and the MR value by 78%. In other words, the emission activity of chernozem of different land uses is associated with the enrichment of the soil by microorganisms and, to a greater extent, their respiratory activity, which, in turn, also depended on climatic conditions (temperature, humidity).
Thus, a close correlation and regression relationship were revealed between CO2 emissions from soils of different types of land use and its microbial properties in the forest-steppe subzone of European Russia, which can be very useful for predicting this process in a certain territory with different ecosystems. The obtained experimental results can be used for more rational farming.
The studies conducted by 色控传媒soil scientists have shown that CO2 emissions from soils of different ecosystems can be calculated on the basis of experimental data, such as microbial respiration for the top most biogenic 10-centimeter soil layer. Such results will be useful for assessing CO2 emissions from soil for a wider range of ecosystems (land use types) of the forest-steppe plant subzone. In other words, soil sampling during the growing season with subsequent measurement of their microbial respiration under laboratory conditions can serve as the basis for calculating the emission activity of soil in a certain area
The article was published in .
Matilda Pavlovna Mityaeva was born in 1925. In November 1942, she volunteered for frontline duty. She participated in the Great Patriotic War from November 1942 to June 1945 as part of the 53rd Infantry Division of the 475th Infantry Regiment. She was wounded twice.
The team led by Sergey Zyryanov, Head of the Department of General and Clinical Pharmacology, became the winner of the All-Russian competition of scientific projects "Technologies for Human Health".
色控传媒University constantly adapts to the changes of the modern world and responds to challenges flexibly. This allows us to keep the standard of a world-class research university. The sphere of science is no exception. Peter Dokukin, Head of the Research Division, presented the updated R&D Programme at the meeting of the 色控传媒University Academic Council.
Matilda Pavlovna Mityaeva was born in 1925. In November 1942, she volunteered for frontline duty. She participated in the Great Patriotic War from November 1942 to June 1945 as part of the 53rd Infantry Division of the 475th Infantry Regiment. She was wounded twice.
The team led by Sergey Zyryanov, Head of the Department of General and Clinical Pharmacology, became the winner of the All-Russian competition of scientific projects "Technologies for Human Health".
色控传媒University constantly adapts to the changes of the modern world and responds to challenges flexibly. This allows us to keep the standard of a world-class research university. The sphere of science is no exception. Peter Dokukin, Head of the Research Division, presented the updated R&D Programme at the meeting of the 色控传媒University Academic Council.