Formation of the structure of microbiocenoses of soils of agroecosystems depending on trophic and hydrothermal factors

Abstract

Ground soil, as the product primarily of the activity of microbiota, is under the permanent influence of ecological and anthropogenous factors. Soils are especially subject to pressure in agroecosystems, which increases due to the considerable fluctuation of climate system parameters. Using graph analysis, we have estimated the results of multiyear monitoring research on the functioning of microbiocenoses of three soil types in agroecosystems depending on the fertilizing and hydrothermal mode. It enabled us to detect peculiarities of formation of the structure soil microbiocenoses and to better understand ecologically important relations between functional groups of microorganisms in the soil depending on action of different factors. It has been determined that neither application of organic and mineral fertilizers into chernozem nor action of hydrothermal factors (temperature air and humidity) is a crucial characteristic of changing in the structure of its microbiocenosis. Microorganisms-producers of exopolysaccharides, which have a strong relationship with all trophic groups of microorganisms as they are their structural components, turned out to be the main block constructing factor, which is due to their strong influence on total content of microbal mass in soil. For soil of agroecosystems with dark-grey type of soil characteristic of content of total biomass of microorganisms is a basis for block constructing gremium, which affirms the state of microbiocenosis and processes occurring there under the action of researched biotic and abiotic factors. Microbiocenosis of sod-podzolic soil, unlike the other researched types of soils, reacted distinctly on applying of fertilizer and depended on the action of hydrothermal factors. Contrast in the range of hydrothermal regime caused a chaotic character of interaction between the basic characteristics in microbiocenosis of sod-podzolic soil with appearance of a direct and mediated relationship among them. Regardless of changes in hydrothermal factors , interactions between characteristics of total microbial mass content, eutrophic microorganisms, which use mineral and organic forms of nitrogen, and producers of exopolysaccharides were stable. It has been proved that estimating of ecological state of soil and influence of applicable agromeasures on it should be conducted according to the indices of total microorganism biomass content in the soil and correlation between the number of microorganisms which form the graph gremium.

Quantitative Composition the Microorganisms of Rhizosphere Agricultural Plants

“…where: X -the cells number in 1 g of dry soil; a -the average number of counted colonies, units; b -humidity coefficient calculated in accordance with DSTU ISO 11465-2001; 10 n -dilution factor; V -the volume suspension taken for sowing, cm 3 ;…”

“…The theoretical bases of microbiocoenoses soil structure formation and functioning were stated in the research of Ukrainian scientists K. Andreyuk and O. Valagurova [2]. Soil microbiota is one the most important factors that determines the formation processes and biological properties of soil, and is a complex of microbiological system, according to V. Patika [3] the content of microorganisms in 1 g of soil is billions of cells. But according to J. Aislabi and J. Deslipp, the diversity of soil microflora is such that 1 g soil contains about 4000 species of microorganisms [4].…”

Activity of the Microbiocenose of the Root Zone of Corn Plants Under the Action of Plant Protection Agents

“…The effectiveness of biological preparations that include living microorganisms depends on the influence of abiotic factors (temperature, moisture, pH, etc.) [7][8][9][10].…”

Effects of different fertilizer systems and hydrothermal factors on microbial activity in the chernozem in Ukraine

“…Climatic factors, including climatic extreme values such as sudden changes in air temperature, droughts, floods and other natural anomalies cause a complex impact on microbiological processes in the soil and its properties, regimes and functions (Kruglov et al, 2012;Ma et al, 2015;Sherstoboeva & Demyanyuk, 2016;Wu et al, 2017;Demyanyuk et al, 2018;Zhao et al, 2018). Depending on the factor which limits the productivity of ecosystems, for example precipitations and accordingly changes in soil moisture, the proportion of number of bacteria and micromycetes can change, as well as the species composition of these groups and their bioecology (Six et al, 2006;Banerjee et al, 2016a).…”