Advanced

The responses of microbial temperature relationships to seasonal change and winter warming in a temperate grassland

Birgander, Johanna LU ; Olsson, Pål Axel LU and Rousk, Johannes LU (2018) In Global Change Biology 24(8). p.3357-3367
Abstract

Microorganisms dominate the decomposition of organic matter and their activities are strongly influenced by temperature. As the carbon (C) flux from soil to the atmosphere due to microbial activity is substantial, understanding temperature relationships of microbial processes is critical. It has been shown that microbial temperature relationships in soil correlate with the climate, and microorganisms in field experiments become more warm-tolerant in response to chronic warming. It is also known that microbial temperature relationships reflect the seasons in aquatic ecosystems, but to date this has not been investigated in soil. Although climate change predictions suggest that temperatures will be mostly affected during winter in... (More)

Microorganisms dominate the decomposition of organic matter and their activities are strongly influenced by temperature. As the carbon (C) flux from soil to the atmosphere due to microbial activity is substantial, understanding temperature relationships of microbial processes is critical. It has been shown that microbial temperature relationships in soil correlate with the climate, and microorganisms in field experiments become more warm-tolerant in response to chronic warming. It is also known that microbial temperature relationships reflect the seasons in aquatic ecosystems, but to date this has not been investigated in soil. Although climate change predictions suggest that temperatures will be mostly affected during winter in temperate ecosystems, no assessments exist of the responses of microbial temperature relationships to winter warming. We investigated the responses of the temperature relationships of bacterial growth, fungal growth, and respiration in a temperate grassland to seasonal change, and to 2 years’ winter warming. The warming treatments increased winter soil temperatures by 5–6°C, corresponding to 3°C warming of the mean annual temperature. Microbial temperature relationships and temperature sensitivities (Q10) could be accurately established, but did not respond to winter warming or to seasonal temperature change, despite significant shifts in the microbial community structure. The lack of response to winter warming that we demonstrate, and the strong response to chronic warming treatments previously shown, together suggest that it is the peak annual soil temperature that influences the microbial temperature relationships, and that temperatures during colder seasons will have little impact. Thus, mean annual temperatures are poor predictors for microbial temperature relationships. Instead, the intensity of summer heat-spells in temperate systems is likely to shape the microbial temperature relationships that govern the soil-atmosphere C exchange.

(Less)
Please use this url to cite or link to this publication:
author
; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Arrhenius and Ratkowsky temperature relationships, experimental warming, temperature dependence, temperature sensitivity (Q), winter warming
in
Global Change Biology
volume
24
issue
8
pages
11 pages
publisher
Wiley-Blackwell
external identifiers
  • pmid:29345091
  • scopus:85049516712
ISSN
1354-1013
DOI
10.1111/gcb.14060
language
English
LU publication?
yes
id
4696a934-5ab2-4fd6-b2ae-402b5247e7b6
date added to LUP
2018-07-20 09:41:33
date last changed
2021-04-11 06:17:18
@article{4696a934-5ab2-4fd6-b2ae-402b5247e7b6,
  abstract     = {<p>Microorganisms dominate the decomposition of organic matter and their activities are strongly influenced by temperature. As the carbon (C) flux from soil to the atmosphere due to microbial activity is substantial, understanding temperature relationships of microbial processes is critical. It has been shown that microbial temperature relationships in soil correlate with the climate, and microorganisms in field experiments become more warm-tolerant in response to chronic warming. It is also known that microbial temperature relationships reflect the seasons in aquatic ecosystems, but to date this has not been investigated in soil. Although climate change predictions suggest that temperatures will be mostly affected during winter in temperate ecosystems, no assessments exist of the responses of microbial temperature relationships to winter warming. We investigated the responses of the temperature relationships of bacterial growth, fungal growth, and respiration in a temperate grassland to seasonal change, and to 2 years’ winter warming. The warming treatments increased winter soil temperatures by 5–6°C, corresponding to 3°C warming of the mean annual temperature. Microbial temperature relationships and temperature sensitivities (Q<sub>10</sub>) could be accurately established, but did not respond to winter warming or to seasonal temperature change, despite significant shifts in the microbial community structure. The lack of response to winter warming that we demonstrate, and the strong response to chronic warming treatments previously shown, together suggest that it is the peak annual soil temperature that influences the microbial temperature relationships, and that temperatures during colder seasons will have little impact. Thus, mean annual temperatures are poor predictors for microbial temperature relationships. Instead, the intensity of summer heat-spells in temperate systems is likely to shape the microbial temperature relationships that govern the soil-atmosphere C exchange.</p>},
  author       = {Birgander, Johanna and Olsson, Pål Axel and Rousk, Johannes},
  issn         = {1354-1013},
  language     = {eng},
  month        = {08},
  number       = {8},
  pages        = {3357--3367},
  publisher    = {Wiley-Blackwell},
  series       = {Global Change Biology},
  title        = {The responses of microbial temperature relationships to seasonal change and winter warming in a temperate grassland},
  url          = {http://dx.doi.org/10.1111/gcb.14060},
  doi          = {10.1111/gcb.14060},
  volume       = {24},
  year         = {2018},
}