Soil Microbial Biomass Assessment Techniques
Summary
Soil microbial biomass constitutes the living fraction of soil organic matter and underpins nutrient cycling, soil structure and ecosystem resilience. Quantification of this dynamic pool relies on direct and indirect approaches. Classical methods include chloroform fumigation‐extraction (CFE) and fumigation‐incubation (CFI), which employ chloroform to lyse cells and measure released carbon, nitrogen or CO₂ evolution. Substrate‐induced respiration (SIR) gauges active biomass through CO₂ release after substrate addition. Phospholipid fatty acid analysis (PLFA) provides both quantitative and qualitative insight into community structure via membrane lipid profiles. Enzyme‐based assays, such as fluorescein diacetate (FDA) hydrolysis and dehydrogenase activity, offer rapid proxies for total microbial activity. Recent advances explore physical cell‐lysis techniques using high‐pressure gases and integrate molecular tools to refine biomass estimates and link them with functional potential. These methods differ in sensitivity, labour intensity and susceptibility to soil properties, necessitating careful selection to suit research aims and soil matrices. Standardisation and cross‐method calibration remain critical for global comparability and for monitoring responses to land use, climate change and management interventions.
Research from Nature Portfolio
No recent Nature Portfolio content available.
Soil Microbial Biomass Assessment Techniques publication trend
The graph below shows the total number of articles in soil microbial biomass assessment techniques across all publications each year (not limited to Nature Index journals).
Technical terms
Chloroform fumigation‐extraction (CFE): A method using chloroform vapour to lyse microbial cells followed by extraction of released carbon or nitrogen to estimate biomass.
Chloroform fumigation‐incubation (CFI): A technique where fumigated soil is incubated to allow mineralisation of released biomass and measurement of CO₂ evolution as a biomass proxy.
Substrate‐induced respiration (SIR): Measurement of CO₂ production after addition of a readily degradable substrate, proportional to active microbial biomass.
Phospholipid fatty acid analysis (PLFA): Extraction and quantification of membrane lipids to profile total microbial biomass and community composition.
High‐pressure gas lysis: A physical approach using elevated CO₂ or N₂ pressure to disrupt microbial cells, releasing intracellular constituents for biomass estimation.
References
- Lysis of soil microbial cells by CO2 or N2 high pressurization compared with chloroform fumigation. Biology and Fertility of Soils (2023).
- Soil microbial functionality in response to the inclusion of cover crop mixtures in agricultural systems. Spanish Journal of Agricultural Research (2016).
- METHODS FOR MEASURING BIOMASS OF SOIL MICROORGANISMS. Russian Journal of Ecosystem Ecology (2018).
About these summaries
This Nature Research Intelligence Topic summary is created with the cited references and a large language model. We take care to ground generated text with facts, and have systems in place to gain human feedback on the overall quality of the process in line with our AI principles. We strive to create accurate and useful summaries for people unfamiliar with the research topic and that supports this goal. These pages are a beta release and will be updated as we learn how best to help people gain value from a research topic summary.
Turn complex research questions into confident strategic decisions
When you're under pressure to set direction, justify investment, or understand your competitive position, you need more than raw data — you need trusted insights you can act on.
Benchmark your performance against global peers using robust, methodologically sound analysis.
Combine quantitative metrics with qualitative expert insight to uncover strengths, gaps and emerging opportunities.
Gain tailored, decision-ready recommendations aligned to your strategic priorities.
Talk to us to learn more about our data dashboards and bespoke strategy reports.
Grow research skills, confidence and careers with training built for every stage of the research lifecycle.
Developed with Nature Portfolio journal Editors and internationally renowned experts. Discover three ways to learn:
Self-paced, online courses in convenient bite-sized units, covering key skills across scientific writing, publishing, grant writing, data analysis, and more.
Expert trainer-led workshops with hands-on exercises and real-time feedback across core research skills, delivered via interactive group sessions.
Editor-led workshops combining core principles in writing and publishing, personalised 1:1 feedback from Nature Portfolio Editors and hands-on exercises.
Explore course catalogues and workshop agendas, enquire about the options or request institutional pricing.