Foto: Fraunhofer IME

Soil is livelihood and biosphere for humans, animals, plants and soil organisms. All the substances brought in are transported, transformed and/or accumulated in the soil.

Soil is sink and , depending on substance and specific soil properties, medium for accumulation as well as intermittent reservoir for all substances entering via atmosphere or direct application. Through litter also substances which settle on the vegetation by dry deposition or filtrating effects enter the soil.

Soil usually consists of horizons parallel to the ground surface. Samples are taken from the organic layer respectively from the root network on urban green areas, from the topsoil (A horizon) and the subsoil (B horizon). The bedrock (C horizon), whichs consists of more or less unchanged parental rock, is not examined. As soil processes run relatively slow and therefore changes are expected only at longer time intervals, the sampling takes place only every four years in September/October.

For more information about the specimen, the sampling and the processing of samples see the Guideline for Sampling and Sample Treatment Soil.

Recommended analysis examples

Target organs/Matrices

  • Organic layer/root network
    The organic layer respectively the root network at urban green spaces is an important specimen because both are in direct contact with the atmosphere and thus with air pollutants and substances which are directly applied to the soil. Furthermore, substances which have been deposited on the vegetation enter the organic layer through litter.
  • Topsoil
    The topsoil (A horizon) is the upper layer of the mineral soil body with high biological activity. It is mostly darker in colour and contains more organic matter than the deeper layer. The topsoil is of special importance in the circulation of contaminants because it is the main root space of plants and the habitat of the majority of soil organism.
  • Subsoil
    The subsoil (B horizon) is often enriched with clay, minerals or organic matter and is therefore also referred to as illuvial horizon. It is the main area of mineralisation. In many soil types the B horizon functions as water reservoir where water soluble pollutants accumulate. Furthermore, the channels of many burrowing soil organisms penetrate the B horizon thus facilitating the contaminant dissemination. The B horizon plays a major role in the cycle of matter because the roots of many plants penetrate through the B horizon and are exposed to the accumulated contaminants. In the subsoil, the samples are taken in the first subsoil horizon of up to 40 cm depth.

Sampling area


Sampling period

2002 - 2019

Extended information

Links to external information and legislation