Drought periods are projected to become more severe and more frequent in many European regions. While effects of single strong droughts on plant and microbial carbon (C) dynamics have been studied in some detail, impacts of recurrent drought events are still little understood.
We tested whether the legacy of extreme experimental drought affects responses of plant and microbial C and nitrogen (N) turnover to further drought and rewetting. In a mountain grassland, we conducted a 13C pulse\uffe2\uff80\uff90chase experiment during a naturally occurring drought and rewetting event in plots previously exposed to experimental droughts and in ambient controls (AC). After labelling, we traced 13C below\uffe2\uff80\uff90ground allocation and incorporation into soil microbes using phospholipid fatty acid biomarkers.
Drought history (DH) had no effects on the standing shoot and fine root plant biomass. However, plants with experimental DH displayed decreased shoot N concentrations and increased fine root N concentrations relative to those in AC. During the natural drought, plants with DH assimilated and allocated less 13C below\uffe2\uff80\uff90ground; moreover, fine root respiration was reduced and not fuelled by fresh C compared to plants in AC.
Regardless of DH, microbial biomass remained stable during natural drought and rewetting. Although microbial communities initially differed in their composition between soils with and without DH, they responded to the natural drought and rewetting in a similar way: gram\uffe2\uff80\uff90positive bacteria increased, while fungal and gram\uffe2\uff80\uff90negative bacteria remained stable. In soils with DH, a strongly reduced uptake of recent plant\uffe2\uff80\uff90derived 13C in microbial biomarkers was observed during the natural drought, pointing to a smaller fraction of active microbes or to a microbial community that is less dependent on plant C.
Synthesis. Drought history can induce changes in above\uffe2\uff80\uff90 vs. below\uffe2\uff80\uff90ground plant N concentrations and affect the response of plant C turnover to further droughts and rewetting by decreasing plant C uptake and below\uffe2\uff80\uff90ground allocation. DH does not affect the responses of the microbial community to further droughts and rewetting, but alters microbial functioning, particularly the turnover of recent plant\uffe2\uff80\uff90derived carbon, during and after further drought periods.
", "keywords": ["0301 basic medicine", "plant-soil (below-ground) interactions", "NITROGEN TURNOVER", "Biomass Allocation", "microbial community composition", "Negibacteria", "drought", "phospholipid fatty acid", "nitrogen", "Microbial community composition", "Plant\u2013Soil (Below\u2010ground) Interactions", "Recovery", "ROOT RESPIRATION", "Plant-soil (below-ground) interactions", "CLIMATE EXTREMES", "C pulse labelling", "Below-ground carbon allocation", "2. Zero hunger", "106022 Mikrobiologie", "0303 health sciences", "SOIL INTERACTIONS", "below-ground carbon allocation", "C-13 pulse labelling", "Grassland", "6. Clean water", "Europe", "Phospholipid", "ORGANIC-MATTER", "Mountain Region", "Posibacteria", "DIOXIDE PULSES", "Phospholipid fatty acid", "106022 Microbiology", "Root/shoot Ratio", "Belowground Biomass", "Ecosystem Resilience", "Nitrogen", "Microbial Community", "Carbon Isotope", "Soil-vegetation Interaction", "recovery", "SUMMER DROUGHT", "03 medical and health sciences", "Rewetting", "Community Composition", "plant\u2013soil (below-ground) interactions", "WATER-STRESS", "resilience", "Drought", "Resilience", "RESILIENCE", "15. Life on land", "Turnover", "Microbial Activity", "13. Climate action", "Fatty Acid", "RESPONSES"]}, "links": [{"href": "https://doi.org/10.1111/1365-2745.12593"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Journal%20of%20Ecology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/1365-2745.12593", "name": "item", "description": "10.1111/1365-2745.12593", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/1365-2745.12593"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2016-05-24T00:00:00Z"}}, {"id": "10.1111/1365-2745.14136", "type": "Feature", "geometry": null, "properties": {"updated": "2026-07-26T16:18:26Z", "type": "Journal Article", "created": "2023-06-08", "title": "Drought intensity alters productivity, carbon allocation and plant nitrogen uptake in fast versus slow grassland communities", "description": "Abstract
Grasslands face more frequent and extreme droughts; yet, their responses to increasing drought intensity are poorly understood. Increasing drought intensity likely triggers abrupt shifts (thresholds) in grassland ecosystem functioning which can implicate recovery trajectories.
Here, we determined how drought intensity affects plant productivity, and plant\uffe2\uff80\uff93soil carbon (C) and nitrogen (N) cycling. We exposed model grassland plant communities with contrasting resource acquisition strategies (a fast\uffe2\uff80\uff90 vs a slow\uffe2\uff80\uff90strategy plant community), to a gradient of drought intensity. The drought gradient ranged from well\uffe2\uff80\uff90watered to severely water\uffe2\uff80\uff90limited conditions. We identified thresholds of plant community productivity (above\uffe2\uff80\uff90ground biomass) at peak drought and 2\uffe2\uff80\uff89months after re\uffe2\uff80\uff90wetting, and measured net ecosystem exchange and ecosystem respiration of C\uffc2\uffa0throughout the drought and recovery phases. At peak drought and 1\uffe2\uff80\uff89week after re\uffe2\uff80\uff90wetting, we traced recently acquired C from plants to the soil and into microbial biomass and fatty acids using 13C pulse labelling, and measured plant and soil N.
At peak drought, slow\uffe2\uff80\uff90strategy plant communities were more drought resistant than fast\uffe2\uff80\uff90strategy communities, as the threshold in plant productivity occurred at a higher drought intensity for the slow\uffe2\uff80\uff90 than the fast\uffe2\uff80\uff90strategy community. Shortly after re\uffe2\uff80\uff90wetting, microbial uptake of recent plant\uffe2\uff80\uff90assimilated C increased with increasing past drought intensity, coinciding with an increase in soil N availability and leaf N. Threshold responses to drought intensity at peak drought translated into non\uffe2\uff80\uff90linear recovery responses, with greater compensatory growth in the fast\uffe2\uff80\uff90strategy community. At peak drought, increasing drought intensity reduced C uptake and increased relative C partitioning to leaves and microbial biomass. Upon re\uffe2\uff80\uff90wetting, plant community strategy mediated drought intensity effects on plant and soil C and N dynamics and plant recovery trajectories. The fast\uffe2\uff80\uff90strategy community recovered quickly, with higher leaf N than the slow community, while the slow community increased C allocation to microbial biomass.
Synthesis. Our findings highlight that C and N dynamics in the plant\uffe2\uff80\uff93soil system display non\uffe2\uff80\uff90linear responses to increasing drought intensity both during and after drought, which has implications for plant community recovery trajectories.
Grasslands face more frequent and extreme droughts; yet, their responses to increasing drought intensity are poorly understood. Increasing drought intensity likely triggers abrupt shifts (thresholds) in grassland ecosystem functioning which can implicate recovery trajectories.
Here, we determined how drought intensity affects plant productivity, and plant\uffe2\uff80\uff93soil carbon (C) and nitrogen (N) cycling. We exposed model grassland plant communities with contrasting resource acquisition strategies (a fast\uffe2\uff80\uff90 vs a slow\uffe2\uff80\uff90strategy plant community), to a gradient of drought intensity. The drought gradient ranged from well\uffe2\uff80\uff90watered to severely water\uffe2\uff80\uff90limited conditions. We identified thresholds of plant community productivity (above\uffe2\uff80\uff90ground biomass) at peak drought and 2\uffe2\uff80\uff89months after re\uffe2\uff80\uff90wetting, and measured net ecosystem exchange and ecosystem respiration of C\uffc2\uffa0throughout the drought and recovery phases. At peak drought and 1\uffe2\uff80\uff89week after re\uffe2\uff80\uff90wetting, we traced recently acquired C from plants to the soil and into microbial biomass and fatty acids using 13C pulse labelling, and measured plant and soil N.
At peak drought, slow\uffe2\uff80\uff90strategy plant communities were more drought resistant than fast\uffe2\uff80\uff90strategy communities, as the threshold in plant productivity occurred at a higher drought intensity for the slow\uffe2\uff80\uff90 than the fast\uffe2\uff80\uff90strategy community. Shortly after re\uffe2\uff80\uff90wetting, microbial uptake of recent plant\uffe2\uff80\uff90assimilated C increased with increasing past drought intensity, coinciding with an increase in soil N availability and leaf N. Threshold responses to drought intensity at peak drought translated into non\uffe2\uff80\uff90linear recovery responses, with greater compensatory growth in the fast\uffe2\uff80\uff90strategy community. At peak drought, increasing drought intensity reduced C uptake and increased relative C partitioning to leaves and microbial biomass. Upon re\uffe2\uff80\uff90wetting, plant community strategy mediated drought intensity effects on plant and soil C and N dynamics and plant recovery trajectories. The fast\uffe2\uff80\uff90strategy community recovered quickly, with higher leaf N than the slow community, while the slow community increased C allocation to microbial biomass.
Synthesis. Our findings highlight that C and N dynamics in the plant\uffe2\uff80\uff93soil system display non\uffe2\uff80\uff90linear responses to increasing drought intensity both during and after drought, which has implications for plant community recovery trajectories.