National foreword

This Published Document is the UK implementation of ISO/TS 18721:2026.

The UK participation in its preparation was entrusted to Technical Committee EH/4, Soil quality.

A list of organizations represented on this committee can be obtained on request to its committee manager.

Contractual and legal considerations

This publication has been prepared in good faith, however no representation, warranty, assurance or undertaking (express or implied) is or will be made, and no responsibility or liability is or will be accepted by BSI in relation to the adequacy, accuracy, completeness or reasonableness of this publication. All and any such responsibility and liability is expressly disclaimed to the full extent permitted by the law.

This publication is provided as is, and is to be used at the recipient’s own risk.

The recipient is advised to consider seeking professional guidance with respect to its use of this publication.

This publication is not intended to constitute a contract. Users are responsible for its correct application.

This publication is not to be regarded as a British Standard.

Compliance with a Published Document cannot confer immunity from legal obligations.

This Published Document was published under the authority of the Standards Policy and Strategy Committee on 31 March 2026.

Foreword

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The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

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This document was prepared by Technical Committee ISO/TC 190, Soil quality.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Introduction

In recent years, the concern for soil sustainability has considerably increased. Many countries are setting targets to reduce soil artificialisation and reinforce ecosystem rehabilitation and biodiversity conservation. In Europe, the recent proposal for a directive on soil monitoring and resilience will set foundations for member states to consider.

In this context, concepts of soil health and soil quality are being discussed^[86^][97^][98^] and ecological soil functions are being proposed^[87^][90^]. However, although several promising propositions have been made to define lists of indicators of soil health and soil quality in different contexts (e.g. Reference [94]), there is presently no consensus.

Based on the definitions of soil health and soil quality presented in ISO/TS 18718, this document aims to provide an overview of the existing indicators and characteristics that are linked to soil functions and the available methods to assess them whether they are internationally standardized, nationally standardized or exist as peer-reviewed work.

1 Scope

This document provides a generic description of the methods available for measuring soil characteristics and indicators of core ecological soil functions. No distinction of context is made, i.e. no differentiation of land use and management (e.g agricultural, forest, urban, natural or contaminated lands). For each ecological soil function, the document specifically lists biotic and abiotic characteristics that can be measured. It focuses on characteristics and indicators that are either available as ISO documents or published in peer-reviewed papers.

This document applies to ecological soil functions and is not applied to soil functions such as geotechnical functions (foundation support for buildings, tunnels, etc.) or geothermal functions. Indeed, ecosystem services do not address soils without a topsoil, or with a covered topsoil (buildings, infrastructure, greenhouse farming, solar panel parks).

Methods and indicators for ecological soil functions can help in the assessment of soil-related ecosystem services but the overall assessment of ecosystem services is not covered in this document.

Other methods based on proxy indicators (e.g. soil occupation, hydrography parameters) can also be used for land planning at large scale. These indicators are not included in this document.

2 Normative references

3 Terms and definitions

4 Indicators of ecological soil functions

4.1 General

4.2 Methods for measuring general soil characteristics and indicators, sampling and soil preparation

4.3 Methods for measuring specific soil characteristics and indicators

Bibliography

PD ISO/TS 18721:2026

Ecological soil functions — Characteristics, indicators and methods

Current

Published:

31 Mar 2026