The impact of summer drought on peat soil microbiome structure and function-A multi-proxy-comparison

Area of Science:

• Microbiology
• Ecology
• Environmental Science

Background:

• Understanding microbiome dynamics is crucial for ecological studies.
• Existing proxies for microbiome analysis have limitations and vary across studies.
• Assessing the impact of environmental changes like drought on soil microbiomes requires robust methods.

Purpose of the Study:

• To compare the effectiveness of four different proxies (16/18S rRNA genes, 16/18S rRNA transcripts, mRNA taxonomy, and mRNA function) in assessing microbiome structure and function.
• To reveal the impact of a severe summer drought on prokaryotic and eukaryotic microbiomes in rewetted fen peatlands.
• To determine the accuracy of different proxies in predicting drought-induced microbiome changes.

Main Methods:

• Utilized amplicon and metatranscriptomic sequencing.
• Compared four distinct proxies: rRNA genes, rRNA transcripts, mRNA taxonomy, and mRNA function.
• Analyzed microbiome composition and function in response to drought in two German rewetted fen peatlands.

Main Results:

• Prokaryotic and eukaryotic microbiome compositions significantly differed between dry and wet months.
• mRNA proxies demonstrated stronger drought impacts for prokaryotes, while 18S rRNA transcripts and mRNA taxonomy were more sensitive for eukaryotes.
• rRNA gene proxies exhibited the lowest accuracy in reflecting drought impacts, highlighting the limitations of DNA-based approaches.

Conclusions:

• Microbiome composition and function are sensitive to extreme weather events like drought in rewetted fens.
• mRNA-based proxies offer a more accurate assessment of drought-induced microbiome dynamics, especially for prokaryotes.
• The choice of proxy significantly influences the understanding of microbiome responses to environmental changes.