Albert Brangarí
Researcher
Linking soil depth to aridity effects on soil microbial community composition, diversity and resource limitation
Author
Summary, in English
With ongoing climate change, aridity is increasing worldwide, affecting biodiversity and ecosystem function in drylands. However, how the depth-profile microbial community structure and metabolic limitations change along aridity gradients are still poorly explored. Here, 16S rRNA and ITS amplicon sequencing and ecoenzymatic stoichiometry analysis were used to investigate both bacterial and fungal diversities and resource limitations in 1 m depth profiles across a wide aridity gradient (0.51–0.78) in a semiarid region. Results showed a sharp decrease in microbial diversity with soil depth, accompanied by an increase in microbial phosphorus (P) vs. N (nitrogen) limitation and a decrease in microbial carbon (C) vs. nutrient limitation. Aridity led to a strong shift in microbial community composition, but aridity has a threshold effect on microbial resource limitation through impacts on soil pH and C/P or N/P. When the aridity threshold (1-precipitation/evapotranspiration) exceeds 0.65, relationship between aridity and microbial resource demand was decoupled; but at aridity threshold = 0.65, microbial relative C limitation and C-acquiring enzyme activity dropped. These results suggest that aridity might have a stronger influence on microbial community composition, than on diversity, shaped by inherent soil biotic factors (i.e., MBC:MBP or MBN:MBP). These findings suggest that soil microbial diversity or enzymatic stoichiometry may be not necessary to mirror changes in water availability in the drylands, while aridity would be well explained by microbial community composition.
Department/s
- Microbial Biogeochemistry in Lund
- Microbial Ecology
- BECC: Biodiversity and Ecosystem services in a Changing Climate
Publishing year
2023-11
Language
English
Publication/Series
Catena
Volume
232
Document type
Journal article
Publisher
Elsevier
Topic
- Ecology
Keywords
- Aridity
- Climate change
- Community structure
- Depth profile
- Metabolism limitation
- Soil microorganism
Status
Published
Research group
- Microbial Biogeochemistry in Lund
- Microbial Ecology
ISBN/ISSN/Other
- ISSN: 0341-8162