0000000001205313
AUTHOR
Romain Barnard
Effects of precipitation regime on soil bacterial and fungal activity upon rewetting of a plant-soil system using 18O-SIP: depth matters
EASPEBIOmEDOCT INRA; Climate change is predicted to affect not only the amount but also the temporal distribution of rain. Changes in frequency and amplitude of rain events, likely shape the activity of plants and soil microbes. Fluctuating water conditions will differ with soil depth between precipitation patterns, affecting plant growth and may result in differential microbial response upon rewetting. Our objective was to investigate, in plant-soil systems, the response of the metabolically active microbial communities to a rewetting event and to which extent this was modulated by 1) soil depth and 2) precipitation legacy. Wheat planted in soil mesocosms were subjected to frequent or infr…
Legacy effects of contrasting water and N-availability patterns on plant-microbial response to rewetting
Shifts in frequency and magnitude of rain events may affect plant physiology and soil microbial activity. We aimed to determine how precipitation history shapes the response dynamics of soil microbial communities to rewetting, as well as plant-microbial competition for N, and how the N status of the system may modulate the effects of precipitation regime. The legacy effects of 12 weeks of contrasting precipitation and N inputs was assessed in wheat mesocosms. The legacy effects on the response to rewetting of potentially active (rRNA-based) bacterial and fungal communities was then documented over 29h, by sequencing phylogenetic marker genes, and following the dynamics of plant-microbial co…
Diurnal pattern of primary metabolites exudation in legume sheds light on the major influence of root NSC and AA status
Legacy effects of contrasting water and N-availability patterns on plantmicrobial response to rewetting
National audience; Introduction. Shifts in the frequency and magnitude of rain events (precipitation regime) associated with climate change may affect plant morphological and physiological strategies as well as soil microbial activity.Objectives. The objective of this study was to determine i) how precipitation history shapes the response dynamics of soil bacterial and fungal communities to rewetting, as well as plant-microbial competition for N, and ii) how the N status of the system may modulate the effect of precipitation regime.Materials & methods. The legacy effects of 12 weeks of contrasting precipitation (frequent or infrequent watering, equal total water input) and N inputs was asse…
Changing summer precipitation pattern alters soil microbial community response to wet-up under a Mediterranean-type climate
Effects of precipitation regime on soil bacterial and fungal activity upon rewetting of a plant-soil system using 18O-SIP : depth matters
Climate change is predicted to a ect not only the amount but also the temporal distribu- tion of rain. Changes in frequency and amplitude of rain events, i.e. precipitation patterns, likely shape the activity of plants and soil microbes. Fluctuating water conditions will dier with soil depth between precipitation patterns, a ecting plant growth and may result in dierential microbial response upon rewetting. Our objective was to investigate, in plant-soil systems, the response of the metabolically active microbial communities to a rewetting event and to which extent this was modulated 1) by soil depth and 2) by precipitation legacy. Wheat planted in soil mesocosms was grown under controlled …
Responses of soil bacterial and fungal communities to extreme soil drought and rewetting
Question: The patterns of resource allocation and activity of the soil microbial community over the dry summer in Mediterranean grasslands are still largely unknown. The microbial response to summer desiccation reflects adaptation strategies, setting the stage for a large rainfall-induced soil CO2 pulse upon rewetting, an important component of the ecosystem carbon budget. Methods: In three California annual grasslands, the present (DNA-based) and potentially active (RNA-based) soil bacterial and fungal communities were tracked over a summer season and in response to controlled rewetting of intact soil cores. Phylogenetic marker genes for bacterial (16S) and fungal (28S) RNA and DNA were se…
Integrated response of plant, microbial and N cycling Interactions to precipitation patterns
Microbial community dynamics induced by rewetting dry soil: summer precipitation matters
The massive soil CO2 efflux associated with rewetting dry soils after the dry summer period significantly contributes to the annual carbon budget of Mediterranean grasslands. Rapid reactivation of soil heterotrophic activity and available carbon are both required to fuel the CO2 pulse. Better understanding of the effects of altered summer precipitation on the metabolic state of indigenous microorganisms may be important in predicting future changes in carbon cycling. We investigated the effects of a controlled rewetting event on the soil CO2 efflux pulse and on the present (DNA-based) and potentially active (rRNA-based) soil bacterial and fungal communities in intact soil cores previously s…
Effects of precipitation regime and N-availability on the dynamics of plant-microbial and soil biogeochemical cycling responses to rewetting
International audience; Introduction. Shifts in the frequency and magnitude of rain events (precipitation regime) associated with climate change may affect plant morphological and physiological strategies as well as soil microbial activity. Objectives. The objective of this study was to determine i) how precipitation history shapes the response dynamics of soil bacterial and fungal communities to rewetting, as well as plant-microbial competition for N, and ii) how the N status of the system may modulate the effect of precipitation regime. Materials & methods. The legacy effects of 12 weeks of contrasting precipitation (frequent or infrequent watering, equal total water input) and N inputs w…
Effects of precipitation regime on soil microbial activity upon rewetting of a plant-soil system
Climate change is predicted to a ect not only the amount but also the temporal distribu- tion of rain. Changes in frequency and amplitude of rain events, i.e. precipitation patterns, likely shape the activity of plants and soil microbes. Fluctuating water conditions will dier with soil depth between precipitation patterns, a ecting plant growth and may result in dierential microbial response upon rewetting. Our objective was to investigate, in plant-soil systems, the response of the metabolically active microbial communities to a rewetting event and to which extent this was modulated 1) by soil depth and 2) by precipitation legacy. Wheat planted in soil mesocosms was grown under controlled …
Changing summer precipitation pattern alters microbial community response to fall wet-up in a Mediterranean soil
The large soil CO2 efflux associated with rewetting dry soils after the dry summer period significantly contributes to the annual carbon budget of Mediterranean grasslands. Rapid reactivation of soil heterotrophic activity and a pulse of available carbon are both required to fuel the CO2 pulse. Better understanding of the effects of altered summer precipitation on the metabolic state of indigenous microorganisms may be important in predicting future changes in carbon cycling. Here, we investigated the effects of a controlled rewetting event on the soil CO2 efflux pulse and on the present (DNA-based) and potentially active (rRNA-based) soil bacterial and fungal communities in intact soil cor…
Rhizodeposition as a functional trait in legumes. Study of trade-off for plant productivity and resilience
Rhizodeposition is the release of organic carbon (C) to the soil that connects the biotic and abiotic components of the C cycle. It can promote C storage to soil but also mediates plant-microbe interactions (Jones et al., 2009). These interactions are complexes as rhizodeposition will influence the composition and functioning of microbial populations which in return are able to increase the availability of nutrients in soil and provide protection against pathogens (Sasse et al., 2018). Despite their importance for current agriculture challenges, plant-soil microbes interactions remain poorly understood due to the methodological challenge they represent and the complexity of actors and proce…
Wet-up response of the microbial community is shaped by soil dry-down patterns
Background/Question/Methods The massive soil CO2 efflux associated with rewetting dry soils after the dry summer period significantly contributes to the annual carbon budget of Mediterranean grasslands. Rapid reactivation of soil heterotrophic activity and available carbon are both required to fuel the CO2 pulse. Better understanding of the effects of altered summer precipitation on the metabolic state of indigenous microorganisms may be important in predicting future changes in carbon cycling. We investigated the effects of a controlled rewetting event on the soil CO2efflux pulse and on the present (DNA-based) and potentially active (rRNA-based) soil bacterial and fungal communities in int…