Search bioRxiv⌕ Search

Biology subjects

Svensson, B. H.

Publications and source records attributed to Svensson, B. H..

2 recordsLinked to original sources

Rewiring of peatland plant-microbe networks outpaces species turnover

Enviro-climatological changes are thought to be causing alterations in ecosystem processes through shifts in plant and microbial communities; however, how links between plant and microbial communities change with enviro-climatological change is likely to be less straightforward but may be fundamental for many ecological processes. To address this, we assessed the composition of the plant community and the prokaryotic community -using amplicon-based sequencing- of three European peatlands that were distinct in enviro-climatological conditions. Bipartite networks were used to construct site-specific plant-prokaryote co-occurrence networks. Our data show that between sites, plant and prokaryotic communities differ and that turnover in interactions between the communities was complex. Essentially, turnover in plant-microbial interactions is much faster than turnover in the respective communities. Our findings suggest that network rewiring does largely result from novel associations between species that are common and shared across the networks. Turnover in network composition is largely driven by novel interactions between a core community of plants and microorganisms. Taken together our results indicate that plant-microbe associations are context dependent, and that changes in enviro-climatological conditions will likely lead to network rewiring. Integrating turnover in plant-microbe interactions into studies that assess the impact of enviro-climatological change on peatland ecosystems is essential to understand ecosystem dynamics and must be combined with studies on the impact of these changes on ecosystem processes.

ecology↗

Effects of long-term warming and enhanced nitrogen and sulfur deposition on microbial communities in a boreal peatland

With ongoing environmental change, it is important to understand ecosystem responses to multiple perturbations over long time scales at in situ conditions. Here, we investigated the individual and combined effects of 18 years of warming and enhanced nitrogen and sulfate deposition on peat microbial communities in a nutrient-poor boreal mire. The three perturbations individually affected prokaryotic community composition, where nitrogen addition had the most pronounced effect, and its combination with the other perturbations led to additive effects. The functional potential of the community, characterized by shotgun metagenomics, was strongly affected by the interactive effects in the combined treatments. The responses in composition were also partly reflected in the functional gene repertoire and in altered carbon turnover, i.e. an increase of methane production rates as a result of nitrogen addition and a decrease with warming. Long-term nitrogen addition and warming-induced changes caused a shift from Sphagnum-dominated plant communities to vascular plant dominance, which likely transact with many of the observed microbial responses. We conclude that simultaneous perturbations do not always lead to synergistic effects, but can also counteract and even neutralize one another, and thus must be studied in combination when attempting to predict future characteristics and services of peatland ecosystems.

microbiology↗