Publication
Title
Experimental drought reduces the transfer of recently fixed plant carbon to soil microbes and alters the bacterial community composition in a mountain meadow
Author
Abstract
Drought affects plants and soil microorganisms, but it is still not clear how it alters the carbon (C) transfer at the plant-microbial interface. Here, we tested direct and indirect effects of drought on soil microbes and microbial turnover of recent plant-derived C in a mountain meadow. Microbial community composition was assessed using phospholipid fatty acids (PLFAs); the allocation of recent plant-derived C to microbial groups was analysed by pulse-labelling of canopy sections with (CO2)-C-13 and the subsequent tracing of the label into microbial PLFAs. Microbial biomass was significantly higher in plots exposed to a severe experimental drought. In addition, drought induced a shift of the microbial community composition, mainly driven by an increase of Gram-positive bacteria. Drought reduced belowground C allocation, but not the transfer of recently plant-assimilated C to fungi, and in particular reduced tracer uptake by bacteria. This was accompanied by an increase of C-13 in the extractable organic C pool during drought, which was even more pronounced after plots were mown. We conclude that drought weakened the link between plant and bacterial, but not fungal, C turnover, and facilitated the growth of potentially slow-growing, drought-adapted soil microbes, such as Gram-positive bacteria.
Language
English
Source (journal)
New phytologist. - Oxford
Publication
Oxford : 2014
ISSN
0028-646X
Volume/pages
201:3(2014), p. 916-927
ISI
000337082000019
Full text (Publisher's DOI)
UAntwerpen
Publication type
Subject
External links
Web of Science
Record
Identification
Creation 18.10.2018
Last edited 27.06.2021