Microbiomes of different ages in Rendzic Leptosols in the Crimean Peninsula

Abstract

Rendzic Leptosols are intrazonal soils formed on limestone bedrock. The specialty of these soils is that parent rock material is more influential in shaping soil characteristics than zonal factors such as climate, especially during soil formation. Unlike fast evolving Podzols due to their leaching regime, Leptosols do not undergo rapid development due to the nature of the limestone. Little is known how microbiome reflects this process, so we assessed microbiome composition of Rendzic Leptosols of different ages, arising from disruption and subsequent reclamation. The mountains and foothills that cover much of the Crimean Peninsula are ideal for this type of study, as the soils were formed on limestone and have been subjected to anthropogenic impacts through much of human history. Microbiomes of four soil sites forming a chronosequence, including different soil horizons, were studied using sequencing of 16S rRNA gene libraries and quantitative PCR. Dominant phyla for all soil sites were Actinobacteria, Proteobacteria, Acidobacteria, Bacteroidetes, Thaumarchaeota, Planctomycetes, Verrucomicrobia and Firmicutes. Alpha diversity was similar across sites and tended to be higher in topsoil. Beta diversity showed that microbiomes diverged according to the soil site and the soil horizon. The oldest and the youngest soils had the most similar microbiomes, which could have been caused by their geographic proximity. Oligotrophic bacteria from Chitinophagaceae, Blastocatellaceae and Rubrobacteriaceae dominated the microbiome of these soils. The microbiome of 700-year old soil was the most diverse. This soil was from the only study location with topsoil formed by plant litter, which provided additional nutrients and could have been the driving force of this differentiation. Consistent with this assumption, this soil was abundant in copiotrophic bacteria from Proteobacteria and Actinobacteria phyla. The microbiome of 50-year old Leptosol was more similar to the microbiome of benchmark soil than the microbiome of 700-year old soil, especially by weighted metrics. CCA analysis, in combination with PERMANOVA, linked differences in microbiomes to the joint change of all soil chemical parameters between soil horizons. Local factors, such as parent material and plant litter, more strongly influenced the microbiome composition in Rendzic Leptosols than soil age.

The Kerch Peninsula in Transition: A Comprehensive Analysis of Land Use and Land Cover Changes Over Thirty Years

“…The southwestern portion of the peninsula is distinguished by the prevalence of dense, saline, heavy clay soils, whereas the northeastern region, with its more pronounced topography, has superior drainage and consequently, less saline soils. In lowland areas, a combination of hydromorphic solonetzes and chestnut-meadow soils is typically observed, which are characterised by high salinity levels due to the region's elevated soil salinity [30][31][32][33].…”

The Kerch Peninsula in Transition: A Comprehensive Analysis and Prediction of Land Use and Land Cover Changes over Thirty Years

“…The southwestern portion of the peninsula is distinguished by the prevalence of dense, saline, heavy clay soils, whereas the northeastern region, with its more pronounced topography, has superior drainage and consequently, less saline soils. In lowland areas, a combination of hydromorphic solonetzes and chestnutmeadow soils is typically observed, which are characterized by high salinity levels due to the region's elevated soil salinity [31][32][33][34].…”

Microbiome of abandoned soils of former agricultural cryogenic ecosystems of central part of Yamal region

“…Data were processed using the pack-ages in the R software environment ( [2] R Team 2021) and QIIME2 (Bolyen et al 2019) as described in Kimeklis et al (2021). Taxonomic assignment of the phylotypes was determined using the Silva 138 database (Quast et al 2013).…”