ISO 23611-1:2006 Soil quality - Sampling of soil invertebrates. Part 1: Hand-sorting and formalin extraction of earthworms

International Organization for Standardization, Geneva; 2006
This part of ISO 23611 has been drawn up since there is a growing need for the standardisation of terrestrial zoological field methods. Such methods, mainly covering the sampling, extraction and handling of soil invertebrates, are necessary for the following purposes:
⎯ biological classification of soils including soil quality assessment;
⎯ terrestrial bioindication and long-term monitoring;
⎯ evaluation of the effects of chemicals on soil animals (ISO 11268-3).
Data for these purposes are gained by standardized methods since they can form the basis for far-reaching decisions (e.g. whether a given site should be remediated or not). In fact, the lack of such standardised methods is one of the most important reasons why bio-classification and bio-assessment in terrestrial (i.e. soil) habitats has so far relatively rarely been used in comparison to aquatic sites.
Originally, the methods described here were developed for taxonomical and ecological studies, investigating the role of earthworms in various soil ecosystems. These animals are without doubt the most important soil invertebrates in temperate regions and, to a lesser extent, in tropical soils. Since Darwin (1881), their influence on soil structure (e.g. aeration, water holding capacity) and soil functions like litter decomposition and nutrient cycling is well-known [8]. Due to their often very high biomass they are also important in many terrestrial food-webs.
Since it is neither possible nor useful to standardize methods for all soil organisms, the most important ones have been selected.