The adjustment of life history strategies drives the ecological adaptations of soil microbiota to aridity

Abstract

Semi-arid and arid regions occupy about 41% of the global terrestrial area and are characterized by long-term droughts and pulsed rainfall.Soil microorganisms can potentially adapt to these stressors because of their resistance and resilience (Bardgett & Caruso, 2020;De Vries et al., 2018;Evans & Wallenstein, 2014). Yet, such adaptations require adjustments in life history strategies, which are those shifts that can be categorized in terms of metabolic changes or tradeoffs in physiological or genetic traits, with distinct strategies dominating in

Tradeoffs of microbial life history strategies drive the turnover of microbial-derived organic carbon in coastal saline soils

“…Biofilm formation and extracellular polysaccharide biosynthesis facilitate the concentration of resources to maintain microbial metabolic activity, which is consistent with previous studies on drought ( Malik and Bouskill, 2022 ) and cold ( Feng et al, 2021 ) stress. The production of osmolytes could maintain the cellular osmotic equilibrium and help to tolerate scarce resources, which is a very expensive energy consumption metabolic trait, and comes at the expense of reducing growth yield ( Malik et al, 2020 ; Li C. N. et al, 2022 ). It takes a large amount of energy (30–110 ATP) to synthesize osmotic substances, which is much greater than those required to synthesize cell walls (30 ATP) ( Chowdhury et al, 2011 ).…”

“…The theoretical partitioning of microbial life history strategies was proposed by Malik et al (2020) , and they used microbial functions as traits and assigned Y-A-S strategies to dominant populations in the community ( Malik and Bouskill, 2022 ). The Y-strategists were defined as microbes that maximize their growth yield by enhancing central metabolism (e.g., C, N, and P metabolism) and biosynthesis ( Malik et al, 2020 ; Li C. N. et al, 2022 ). The A-strategists were defined as microbes that invested more in functional traits that are associated with the complex substrates degradation, extracellular enzymes production, cell motility, transporters and siderophores ( Malik et al, 2020 ; Shao et al, 2021 ).…”

“…Metagenomic sequencing showed advantages in analyzing the microbial taxonomic community, as well as its functions and genes ( Yang et al, 2021 ), and can provide a deeper understanding of the mechanisms of microbial-mediated SOC formation under stress habitats. Previous researchers have revealed the metabolic efficiency, microbial traits, and their underlying consequences on soil C dynamics under abiotic stress, such as cold ( Feng et al, 2021 ) and drought stress ( Li C. N. et al, 2022 ; Malik and Bouskill, 2022 ). However, the effect of salt stress on how microorganisms regulate their CUE and further affect SOC formation through the alternation of microbial life history strategies is rarely studied.…”

Ecological strategies of microbes: Thinking outside the triangle

“…Fewer studies had explored relationships between high YAS, likely because this framework was proposed only recently (Malik, Martiny, et al, 2020). Among them, there was little support for high yield trading off with competitive or stress tolerance traits (Figure 2); the only exception was a negative relationship between high yield and stress tolerance traits in soil microbial communities from arid grasslands (Li et al, 2022). Possibly, fast growth rates associated with the ruderal strategy more directly trade‐off with competitive and stress tolerance traits than does high yield.…”

“…Regarding the ruderal strategy, fast growth rates were often negatively related to high yield (Figure 2; Li et al, 2022; Lipson et al, 2009; Novak et al, 2006; Roller et al, 2016), so perhaps microbes can elicit fast maximum growth or high yield, but not both. Between the ruderal and high yield strategies, resource requirements for the ruderal strategy may overlap more with the competitive and stress tolerance strategies than do those for the high yield strategy.…”