Dataset Information

Depth matters: effects of precipitation regime on soil microbial activity upon rewetting of a plant-soil system.

ABSTRACT: Changes in frequency and amplitude of rain events, that is, precipitation patterns, result in different water conditions with soil depth, and likely affect plant growth and shape plant and soil microbial activity. Here, we used 18O stable isotope probing (SIP) to investigate bacterial and fungal communities that actively grew or not upon rewetting, at three different depths in soil mesocosms previously subjected to frequent or infrequent watering for 12 weeks (equal total water input). Phylogenetic marker genes for bacteria and fungi were sequenced after rewetting, and plant-soil microbial coupling documented by plant 13C-CO2 labeling. Soil depth, rather than precipitation pattern, was most influential in shaping microbial response to rewetting, and had differential effects on active and inactive bacterial and fungal communities. After rewetting, active bacterial communities were less rich, more even and phylogenetically related than the inactive, and reactivated throughout the soil profile. Active fungal communities after rewetting were less abundant and rich than the inactive. The coupling between plants and soil microbes decreased under infrequent watering in the top soil layer. We suggest that differences in fungal and bacterial abundance and relative activity could result in large effects on subsequent soil biogeochemical cycling.

SUBMITTER: Engelhardt IC

PROVIDER: S-EPMC5864200 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Depth matters: effects of precipitation regime on soil microbial activity upon rewetting of a plant-soil system.

Engelhardt Ilonka C IC Welty Amy A Blazewicz Steven J SJ Bru David D Rouard Nadine N Breuil Marie-Christine MC Gessler Arthur A Galiano Lucía L Miranda José Carlos JC Spor Aymé A Barnard Romain L RL

The ISME journal 20180223 4

Changes in frequency and amplitude of rain events, that is, precipitation patterns, result in different water conditions with soil depth, and likely affect plant growth and shape plant and soil microbial activity. Here, we used <sup>18</sup>O stable isotope probing (SIP) to investigate bacterial and fungal communities that actively grew or not upon rewetting, at three different depths in soil mesocosms previously subjected to frequent or infrequent watering for 12 weeks (equal total water input) ...[more]

PMID: 29476139

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Dataset Information

Depth matters: effects of precipitation regime on soil microbial activity upon rewetting of a plant-soil system.

Publications

Depth matters: effects of precipitation regime on soil microbial activity upon rewetting of a plant-soil system.

Similar Datasets

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