Estimation of microbial diversity in the desert steppe surface soil and buried palaeosol (IV mil. BC) using the TRFLP method. (December 2019)

• Record Type: Journal Article
• Authors: Khomutova, T.E.; Borisov, A.V.
• Is Part Of: Journal of arid environments. Volume 171(2019)
• Publication Date: 2019-12
• Subjects: Microbial diversity -- Subkurgan palaeosol -- Desert steppe zone; Arid regions ecology -- Periodicals; Arid regions -- Periodicals; Écologie des régions arides -- Périodiques; Régions arides -- Périodiques; 577.54
• DOI: 10.1016/j.jaridenv.2019.104004
• Languages: English
• ISSNs: 0140-1963

Abstract

Abstract: A comparative analysis of bacterial diversity was performed on the surface soil (Kastanozem) and palaeosol buried beneath the burial mound (IV mil. BC) in the desert steppe zone of Russia using terminal restriction fragment length polymorphism (TRFLP). In both surface soil and buried palaeosol the morphological and chemical properties were similar. The bacterial communities were highly diverse and in the exposed surface soil 55–106 and in the palaeosol 47–67 TR-fragments were detected. About 40% of communities were specific for the respective soil. A part of the detected phylotypes was identified upon comparison to the ribosomal RNA database. In both soils the communities included halophilic/halotolerant, but not necessarily spore-forming, bacteria. High proportions of gram-negative bacterial groups and an abundance of groups without evident dominance may point to a balanced soil microbiota. Abundant bacterial groups in the surface soil were sparse in the palaeosol; in contrast, the palaeosol microbial community contained bacterial groups not detected in the surface soil. The majority of bacterial groups detected were connected to plant and animal functions in soil. Despite long-term burial, the bacterial community from the palaeosol has maintained its initial structure to a certain degree and contains microorganisms not observed in the surface soil. This confirms high temporal sustainability of bacteria and their tight connection to peculiarities of past environmental conditions contributing to understanding climate dynamics and soil evolution. Highlights: Bacterial diversity in surface soil and palaeosol is studied by the TRFLP method. Halophilic/halotolerant and not necessarily spore-forming bacteria are detected. Abundance of bacterial groups points to a balanced existence of soil microbiota. Bacterial groups detected are related to plant and animal functions in soil. Bacterial community of palaeosol reflects past environmental conditions.