The development and use of soil quality indicators for assessing the role of soil in environmental interactions Science Report SC030265
Read the full reportThe project builds on previous research to establish a tiered, risk-based soil monitoring network, identifying nine key functional soil quality indicators: soil organic carbon, total nitrogen, Olsen P, available and total copper (Cu), nickel (Ni) and zinc (Zn), bulk density, and pH. This methodology ensures the effective assessment of soil health and environmental interaction, providing a robust framework for policy decisions and long-term soil management across the UK.
This project builds on the findings of the previous Environment Agency-led project, Identification and development of a set of national indicators for soil quality (Loveland et al., 2002). Which concluded that soil quality indicators (SQIs) should be based on soil function, with the most important functions being those of environmental interaction, food and fibre production, building platform, support for ecological habitat and biodiversity, the provision of raw materials and protection of cultural heritage. From a choice of 67, the report identified nine key functional soil quality indicators.
This report assessed indicators identified in the first project, and others not yet identified, in terms of their relevance to, sensitivity to and discrimination of soil quality. The report’s objectives were to:
- Develop a methodology for challenging the indicators, which is transparent, auditable and through which uncertainties and expert judgement can be incorporated.
- Establish procedures for using the indicators depending on different requirements for information, for example for policy questions at a national scale or more localised, contextualised issues of concern.
- Test the selected indicators using medium to long-term scenarios, such as climate or land use change, using extrapolated datasets to establish a minimum dataset (MDS) – the minimum number of indicators needed for policy decisions and national-scale assessments.
- Select trigger values or workable ranges for those indicators chosen for the MDS, above or below which change would be critical in terms of the soil’s fitness for a specific use. Using these triggers, soils sampled at different time intervals could be compared and the changes interpreted.
- Gain a broad consensus across the UK soil science community of the suitability of potential indicators for soil monitoring in the UK
This project established a tiered, risk-based procedure for users to select indicators for soil sampling and monitoring based on identified levels of risk, in line with the UK government’s guidance for environmental risk assessment.
This project established:
- a process for assessing the suitability of soil quality indicators (SQIs) to measure the soil function of environmental interaction for a national soil monitoring network
- a tiered, risk-based approach to using these indicators which caters for the broad soil interests of agencies and stakeholders;
- agreement on a minimum dataset (MDS) of soil quality indicators for the soil function of environmental interaction that is soil organic carbon, total nitrogen, Olsen P, available and total copper (Cu), nickel (Ni) and zinc (Zn), bulk density and pH;
- approaches to determine critical changes in these indicators to trigger further action
- agreement from technical representatives and the UK Soil Indicators Consortium on approaches and findings
Recommendations for policy implementation
- Implement a national soil monitoring network
- Adopt a Tiered, Risk-Based Approach
- Establish Trigger Values for Soil Indicators