ISO 18400-206:2018

Overview

ISO 18400-206:2018 - Soil quality - Sampling - Part 206 provides standardized procedures for the collection, handling and storage of soil under aerobic conditions for laboratory assessment of microbiological processes, biomass and diversity. Published by ISO, this standard applies when soil is used to evaluate effects on microorganisms, invertebrates and plants in laboratory tests. It is intended mainly for temperate soils and is not applicable where anaerobic conditions must be maintained.

Key topics and technical requirements

• Objective: Minimize alterations in soil biological activity caused by differences in temperature, water content and oxygen availability, and by particle fractionation, to ensure reproducible laboratory determinations.
• Sampling design: Selection of representative sampling locations based on study purpose, preliminary information and site conditions; geo-referencing and statistical sampling patterns recommended.
• Preliminary survey: Desk study and site visit (limited sampling if safe) to inform sampling strategy and health & safety measures.
• Site description: Record soil type, horizons, vegetation, topography, contamination history and other field context for traceability.
• Sampling conditions and methods: Sample at appropriate moisture for sieving; avoid sampling immediately after prolonged drought, freezing or flooding unless field-monitoring objectives require it. Remove surface litter and visible fauna to reduce fresh organic input.
• Sample handling: Marking, transport and laboratory processing aimed at preserving aerobic microbial communities and test-relevant soil properties.
• Storage and pre-incubation: Procedures for storage periods, conditions and any pre-incubation prior to testing to reduce variability (applicable details are specified in the standard).
• Reporting: Comprehensive sampling report to document methods, conditions and any deviations.

Practical applications and users

ISO 18400-206 is used by:

• Soil scientists and ecotoxicologists conducting lab bioassays of soil organisms
• Environmental consultants and regulatory laboratories performing soil quality and contamination impact assessments
• Agricultural researchers and testing labs measuring soil microbial biomass, activity and diversity
• Remediation professionals evaluating effects of contaminants or treatments on soil biota

Common applications:

• Laboratory assessment of microbial respiration, enzyme activity and biomass
• Ecotoxicological tests on soil invertebrates and plants (survival, growth, reproduction)
• Standardized sample handling for research, monitoring and regulatory compliance

Related standards

• ISO 18400 series: ISO 18400-101 (sampling plan framework), 18400-102, 18400-104, 18400-107, 18400-202, 18400-205
• For field collection of soil organisms: ISO 23611-1 to ISO 23611-6

Keywords: ISO 18400-206, soil quality, soil sampling, aerobic conditions, microbiological processes, soil storage, soil handling, soil biomass, soil diversity, laboratory assessment.