Homogeneous Selection and Dispersal Limitation Dominate the Effect of Soil Strata Under Warming Condition

Abstract

Global warming is likely to affect the underground microbial communities in various ecosystems, but the response of soil microbial communities along a vertical depth profile to global warming has been elusive. Herein, we leveraged a warming field experiment in Qinghai-Tibet Plateau grassland and investigated the community structure of prokaryotes and fungi from the upper (0–15 cm) and lower (15–30 cm) strata under ambient and elevated temperature treatments. Three-years continual warming only significantly shifted the prokaryotic community within the upper strata and there was no significant effect observed for the fungal community. Additionally, under ambient temperature, there were significant differences between the two strata in both the prokaryotic and fungal communities, but under warming, this effect was alleviated. Next, the prokaryotic and fungal community assembly processes were measured by a phylogenetic-bin-based null approach (iCAMP). Though deterministic and stochastic processes dominated the assembly of prokaryotic and fungal communities, respectively, the deterministic processes were strengthened under warming for both communities. Specifically, the increased portion of homogeneous selection, contributing to a homogenous state, led to a smaller difference between prokaryotic communities of the two soil strata under warming. The smaller difference in the stochastic process component, i.e., dispersal limitation, contributed to the similar fungal community structures between the two strata under warming. This study deepens our understanding of warming effects on grassland microbial communities and gives greater insights on the underlying mechanisms for microbial assembly between upper and lower soil strata under warming scenarios.

Soil microbial subcommunity assembly mechanisms are highly variable and intimately linked to their ecological and functional traits

“…We also found that homogeneous selection played an important role in soil microbial community assembly (Figures 2a,b). This finding is supported by several recent studies and may be elucidated as follows (Wang, Feng, et al., 2022; Wang, Liu, et al., 2022; Zhao et al., 2022). First, farmlands typically experience frequent fertilization and disturbances (e.g.…”

Soil bacterial communities are influenced by soil chemical characteristics and dispersal limitation in commercial strawberry production systems

“…In the context of standard strawberry production practices, such uniform selective pressures could be from tillage, soil fumigation, or application of plastic tarps throughout the growing season (Bolda et al, 2015). Similar predominance of homogenous selection has also been observed in aquatic and terrestrial ecosystems, including agricultural soils (Allen et al, 2020;Barnett et al, 2019;Fodelianakis et al, 2021;Jiao & Lu, 2020;Wang, Feng, et al, 2022). Interestingly, less than 1% of comparisons among samples within plots were classified as stochastic processes for ASV data, while about 25% were classified as stochastic processes for OTU data.…”

Assembly processes of rhizosphere and phyllosphere bacterial communities in constructed wetlands created via transformation of rice paddies

“…In general, homogeneous selection dominates the assembly of prokaryotic communities ( Wang et al, 2022 ). Soil physicochemical properties are the primary determinants of the root-associated construction of the bacterial community, followed by environmental factors, host genotype, and nutrient availability ( Ren et al, 2020 ; Stopnisek and Shade, 2021 ).…”