ISO 14240-1-1997 PDF
Name in English:
St ISO 14240-1-1997
Name in Russian:
Ст ISO 14240-1-1997
Original standard ISO 14240-1-1997 in PDF full version. Additional info + preview on request
Full title and description
Soil quality — Determination of soil microbial biomass — Part 1: Substrate-induced respiration method. This International Standard specifies a laboratory procedure to estimate the active aerobic, heterotrophic microbial biomass in aerated agricultural and mineral soils by measuring respiration induced after addition of a readily available substrate.
Abstract
Part 1 of ISO 14240 provides the substrate-induced respiration (SIR) technique: a short-term measurement of CO2 evolution following substrate addition used to estimate microbial biomass C in aerated soils. The method is intended for routine analyses and research where an active, aerobic biomass estimate is required.
General information
- Status: Published (International Standard; confirmed as current by ISO review process).
- Publication date: 1997-01 (January 1997).
- Publisher: International Organization for Standardization (ISO).
- ICS / categories: 13.080.30 — Biological properties of soils.
- Edition / version: Edition 1 (1997).
- Number of pages: 4 pages.
Scope
Specifies a substrate-induced respiration procedure to estimate the active aerobic, heterotrophic microbial biomass in aerated agricultural and mineral soils. The part is focused on estimating microbial biomass by measuring the short-term increase in CO2 production after substrate addition and does not cover determination of effects of chemicals on biomass.
Key topics and requirements
- Principle: addition of a readily metabolizable substrate and measurement of induced CO2 evolution (respiration) to infer microbial biomass.
- Sample handling: requirements for representative, aerated soil samples and control of moisture/water‑holding capacity for reproducible respiration measurements.
- Measurement: short-term CO2 measurement after substrate addition (instrumentation and timing guidance to obtain initial respiration response).
- Calculations: conversion of induced respiration rate to microbial biomass carbon using specified factors and reporting units.
- Applicability and limits: intended for aerobic agricultural and mineral soils; not intended for direct assessment of chemical toxicity effects or for strongly anaerobic/waterlogged soils without adaptation.
Typical use and users
Used by soil testing and environmental laboratories, soil ecologists, agronomists, environmental consultants and research institutions for monitoring soil biological status, assessing soil fertility and comparing management effects. Specialized laboratory capability (gas/CO2 measurement and controlled incubation) is normally required.
Related standards
ISO 14240 is a multi-part series; Part 2 (ISO 14240-2:1997) describes the fumigation‑extraction method for microbial biomass and is commonly referenced alongside Part 1 when comprehensive biomass assessment is needed. In several regions the ISO text has been adopted as EN ISO / national equivalents (for example EN ISO 14240-1:2011 / DIN EN ISO 14240-1), and some national bodies replaced or republished the text under regional standards.
Keywords
soil quality; microbial biomass; substrate-induced respiration; SIR; soil microbiology; soil testing; biomass carbon; aerated soils; ISO 14240-1.
FAQ
Q: What is this standard?
A: ISO 14240-1:1997 is an International Standard that specifies the substrate-induced respiration method to estimate active aerobic, heterotrophic microbial biomass in aerated agricultural and mineral soils.
Q: What does it cover?
A: It covers the laboratory procedure (sample handling, substrate addition, incubation/measurement and calculation) for measuring induced CO2 respiration and converting that response into an estimate of microbial biomass C. It does not cover assessing chemical effects on biomass.
Q: Who typically uses it?
A: Soil and environmental testing laboratories, researchers in soil biology and ecology, agronomists and environmental consultants who need standardized, comparable estimates of active microbial biomass in aerated soils.
Q: Is it current or superseded?
A: The ISO bibliographic record shows ISO 14240-1:1997 as the published Part 1 and that the document has been subject to ISO periodic review/confirmation (ISO records indicate confirmation activity in the 2025 review cycle). However, some national bodies republished or replaced their national adoption with regional versions (for example EN ISO 14240-1:2011) and national catalogues may show the original national adoption as withdrawn in favor of the regional adoption. Check the appropriate national/regional standards body for current local status.
Q: Is it part of a series?
A: Yes — ISO 14240 is a series on soil microbial biomass; Part 1 is the substrate-induced respiration method and Part 2 covers the fumigation‑extraction method (ISO 14240-2:1997). Users often consult both parts when selecting or comparing methods for microbial biomass determination.
Q: What are the key keywords?
A: Soil quality, microbial biomass, substrate-induced respiration, SIR, biomass carbon, soil microbiology, ISO 14240.