Abstract
Summary 1. Depending on grazing intensity, grasslands tend towards two contrasting systems that differ in terms of species diversity and soil carbon (C) storage. To date, effects of grazing on C cycling have mainly been studied in grasslands subject to constant grazing regimes, whereas little is known for grasslands experiencing a change in grazing intensity. Analysing the transition between C‐storing and C‐releasing grasslands under low‐ and high‐grazing regimes, respectively, will help to identify key plant–soil interactions for C cycling. 2. The transition was studied in a mesocosm experiment with grassland monoliths submitted to a change in grazing after 14 years of constant high and low grazing. Plant–soil interactions were analysed by following the dynamics of plant and microbial communities, roots and soil organic matter fractions over 2 years. After disturbance change, mesocosms were continuously exposed to 13 C‐labelled CO 2 , which allowed us to trace both the incorporation of new litter C produced by a modified plant community in soil and the fate of old unlabelled litter C. 3. Changing disturbance intensity led to a cascade of events. After shift to high disturbance, photosynthesis decreased followed by a decline in root biomass and a change in plant community structure 1.5 months later. Those changes led to a decrease of soil fungi, a proliferation of Gram(+) bacteria and accelerated decomposition of old particulate organic C (<6 months). At last, accelerated decomposition released plant available nitrogen and decreased soil C storage. Our results indicate that intensified grazing triggers proliferation of Gram(+) bacteria and subsequent faster decomposition by reducing roots adapted to low disturbance. 4. Synthesis . Plant communities exert control on microbial communities and decomposition through the activity of their living roots: slow‐growing plants adapted to low disturbance reduce Gram(+) bacteria, decomposition of low and high quality litter, nitrogen availability and, thus, ingress of fast‐growing plants. Our results indicate that grazing impacts on soil carbon storage by altering plant roots and their control on the soil microbial community and decomposition, and that these processes will foster decomposition and soil C loss in more productive and disturbed grassland systems.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 11
Claim · model-written summary
After the shift to high disturbance, photosynthesis decreased.
Not reportedComparator
Verbatim
e0“mesocosm experiment with grassland monoliths”
e2“After shift to high disturbance, photosynthesis decreased followed by a decline in root biomass and a change in plant community structure 1.5 months later”
Claim · model-written summary
After the shift to high disturbance, root biomass declined.
Not reportedComparator
Verbatim
e0“mesocosm experiment with grassland monoliths”
e2“After shift to high disturbance, photosynthesis decreased followed by a decline in root biomass and a change in plant community structure 1.5 months later”
Claim · model-written summary
After the shift to high disturbance, plant community structure changed 1.5 months later.
- Taxon
- grasslande0
- Treatment
- shift to high disturbancee2
- Outcome
- plant community structuree2
- Qualifier
- 1.5 months latere2
Not reportedComparatorDirection
Verbatim
e0“mesocosm experiment with grassland monoliths”
e2“After shift to high disturbance, photosynthesis decreased followed by a decline in root biomass and a change in plant community structure 1.5 months later”
Claim · model-written summary
Changing disturbance intensity decreased soil fungi.
Not reportedComparator
Verbatim
e0“mesocosm experiment with grassland monoliths”
e1“Changing disturbance intensity led to a cascade of events”
e3“Those changes led to a decrease of soil fungi, a proliferation of Gram(+) bacteria and accelerated decomposition of old particulate organic C (<6 months)”
Claim · model-written summary
Changing disturbance intensity led to a proliferation of Gram(+) bacteria.
- Taxon
- grasslande0
- Treatment
- Changing disturbance intensitye1
- Outcome
- Gram(+) bacteriae3
- Direction
- proliferatione3
Not reportedComparator
Verbatim
e0“mesocosm experiment with grassland monoliths”
e1“Changing disturbance intensity led to a cascade of events”
e3“Those changes led to a decrease of soil fungi, a proliferation of Gram(+) bacteria and accelerated decomposition of old particulate organic C (<6 months)”
Claim · model-written summary
Changing disturbance intensity accelerated decomposition of old particulate organic C.
- Taxon
- grasslande0
- Treatment
- Changing disturbance intensitye1
- Outcome
- accelerated decomposition of old particulate organic Ce3
- Direction
- acceleratede3
- Qualifier
- <6 monthse3
Not reportedComparator
Verbatim
e0“mesocosm experiment with grassland monoliths”
e1“Changing disturbance intensity led to a cascade of events”
e3“Those changes led to a decrease of soil fungi, a proliferation of Gram(+) bacteria and accelerated decomposition of old particulate organic C (<6 months)”
Claim · model-written summary
Accelerated decomposition released plant available nitrogen.
- Taxon
- grasslande0
- Treatment
- Changing disturbance intensitye1
- Outcome
- plant available nitrogene4
- Direction
- increaseinferrede4
Not reportedComparator
Verbatim
e0“mesocosm experiment with grassland monoliths”
e1“Changing disturbance intensity led to a cascade of events”
e4“At last, accelerated decomposition released plant available nitrogen and decreased soil C storage”
Claim · model-written summary
Changing disturbance intensity decreased soil C storage.
- Taxon
- grasslande0
- Treatment
- Changing disturbance intensitye1
- Outcome
- soil C storagee4
- Direction
- decreasede4
Not reportedComparator
Verbatim
e0“mesocosm experiment with grassland monoliths”
e1“Changing disturbance intensity led to a cascade of events”
e4“At last, accelerated decomposition released plant available nitrogen and decreased soil C storage”
Claim · model-written summary
Intensified grazing triggers Gram(+) bacteria proliferation and faster decomposition by reducing roots adapted to low disturbance.
Verbatim
e0“mesocosm experiment with grassland monoliths”
e5“Our results indicate that intensified grazing triggers proliferation of Gram(+) bacteria and subsequent faster decomposition by reducing roots adapted to low disturbance”
Claim · model-written summary
Plant communities control decomposition through the activity of their living roots.
Verbatim
e0“mesocosm experiment with grassland monoliths”
e6“Plant communities exert control on microbial communities and decomposition through the activity of their living roots”
Claim · model-written summary
Grazing impacts soil carbon storage by altering plant roots and their control on the soil microbial community.
Verbatim
e0“mesocosm experiment with grassland monoliths”
e7“grazing impacts on soil carbon storage by altering plant roots and their control on the soil microbial community”