ISO 23611-2:2024

Overview

ISO 23611-2:2024 - "Soil quality - Sampling of soil invertebrates - Part 2: Sampling and extraction of micro-arthropods (Collembola and Acarina)" specifies standardized methods for collecting, extracting and preserving soil micro-arthropods (springtails and mites) from field soils. The standard provides a reproducible protocol for using Collembola and Acarina as bio‑indicators to assess soil quality, habitat condition and effects of land use or pollution. Methods are applicable to most soils (exceptions: extreme frozen, hardened or flooded soils, and non‑soil matrices such as tree trunks or lichens).

Key topics and technical requirements

• Sampling principle: Use a stainless steel or aluminium split corer (example dimensions: ~40 cm long, ~5–6 cm diameter) to collect cores. Separate litter and upper mineral soil (upper 10 cm commonly sampled; 5 cm layers recommended for mineral horizons).
• Extraction principle: Behavioral extraction using a MacFadyen (high‑gradient) apparatus - a temperature and humidity gradient drives micro‑arthropods out of the sample into a collecting device.
• Alternative extraction: Flotation methods (e.g. heptane flotation) for clay/loamy soils and Kempson extractor for litter samples are acknowledged.
• Test materials & reagents: Descriptions of target taxa (Collembola and Acarina) and a list of recommended reagents for clearing, fixing and preserving specimens (e.g. ethanol 70–75 %, von Törne fixative, lactophenol, Hoyer’s medium).
• Apparatus & tools: Field and lab equipment including measuring tape, stereomicroscope, microscopes with phase/contrast, Petri dishes, vials, heating plates, drying oven, and sampling frames for litter (25×25×15 cm).
• Procedure elements: Field sampling, core handling and storage, extraction timing (rapid extraction within days), sorting, preservation, specimen preparation and identification hints. Annexes provide species determination guidance and an alternative sampling method.
• Data reporting: Abundance recalculation options (per area, volume or weight) and guidance for study reports and result assessment.

Practical applications and users

ISO 23611-2:2024 is intended for:

• Soil ecologists and researchers conducting biodiversity and functional studies of soil fauna.
• Environmental monitoring programs and long‑term biodiversity monitoring using bio‑indicators.
• Soil quality assessors, environmental consultants, agronomists and forest managers evaluating effects of land‑use practices or pollution.
• Accredited laboratories performing standardized sampling and extraction for comparative studies.

Practical uses include habitat quality assessment, baseline surveys, impact assessments (pollution, forestry, agriculture), and standardized data collection to enable reliable site-to-site and over-time comparisons.

Related standards

• ISO 23611 series (other parts cover earthworms, enchytraeids, nematodes, macroinvertebrates)
• ISO 18400-104 (guidance on sampling design and site investigation strategies)

Keywords: soil quality, sampling of soil invertebrates, micro-arthropods, Collembola, Acarina, MacFadyen extractor, split corer, bio-indicators, soil monitoring, ISO 23611-2:2024.