Laboratory Study of the Effect of Ammonium and Lanthanum Salts on Methane Oxidation and Composition of Microbial Communities in Soddy-Podzolic Soil

Assessment of the response of soil microbial communities, performing important ecological and biospheric functions, to natural or anthropogenic impacts is one of the promising approaches to solve the problems of stress resilience of ecosystems. A model experiment with soddy-podzolic soil (Eutric Albic Retisol (Abruptic, Loamic)) has shown the inhibitory effect of ammonium and the stimulating effect of lanthanum on methane oxidation by soil microorganisms. The application of ammonium and lanthanum reduced the taxonomic diversity of the soil bacterial community and changed its structure: the relative content of gram-positive bacteria of Actinobacteriota and Bacillota phyla decreased, while the portion of gram-negative bacteria of the phylum Pseudomonadota increased. Applied lanthanum causes a significant (by several orders of magnitude) rise in the relative content of methanotrophs of Methylobacter genus and of obligate methylotrophs of Methylotenera genus in the community. The results of this work may be used to develop approaches for the control of the activity of the soil methane filter and of the accompanying microbiota.