Changes of Microbial Community in the Irrigative Grey-Brown and Grey-Meadow Soils under Vegetable Cultures of Dry Subtropical Zone

Introduction: Soils contain a very high, but mostly unknown biodiversity, and soil biology remains an
under studied topic. Soil organisms are a key factor for soil development and in turn depend on soils
as a habitat. Microorganisms carrying out metabolic processes remove nutrients from the ecosystem
and use them to build new cells. Microorganisms are the backbone of all ecosystems. Microbes are
decomposers, with the ability to recycle nutrients from other organisms' waste products.
Aims: The objective of this study was to examine the distribution of microorganisms in different types
of agricultural soils.
Study Design: Comparative analysis of quantity of microorganisms in a crop rotation and constant
(permanent) in a dry subtropical zone in different types of soils.
Methodology: Microorganisms quantity has been defined by (microorganisms total quantity meatpeptone-
agaric (MPA) and starchy-ammoniac-agaric (SAA), actinomycetes starchy - agaric- agaric
(SAA) and microscopic fungus quantity have been defined on Chapek agaric environment on the
basis of the method received in the Institute of Microbiology of Moscow.
Results: The results showed that the quantity of microorganisms in a crop rotation was more, than
permanent cultivation of these cultures. A mineralization of organic substances in soils under constant
cultures occurred more intensively, than in a crop rotation.
Conclusion: Including in a crop rotation of legume cultures (Lucerne, haricot, bean) increases
quantity of microorganisms, also slows down intensity mineralization of organic substances. This
study showed that the soil microbial metabolic functional diversity had high variability. The number of
bacteria in the irrigated meadow-serozemic soils was smaller than in the gray-brown soils, and the
number of actinomycetes was on the contrary higher in the grey-brown and meadow-serozemic soils.
The meadow-serozemic soils were characterized by the maximal intensity of the mineralization of the
plant residues among the studied soils.