The function of soil biodiversity as indicators of soil quality: Insights from the UK Defra SQID project

This presentation outlines the final results from the UK Defra SQID project which identified and piloted a suite of biological indicators of soil quality for deployment in national-scale soil monitoring programmes to meet a range of UK policy objectives. The indicators were selected to provide information on the soil biological processes which underpin soil function and therefore support ecosystem services. A semiquantitative framework was used to systematically capture the wealth of information in the literature and from expert knowledge on potential indicators of soil quality with a total of 183 indicators assessed. Six soil biological methods have now been piloted in the UK using two complementary field approaches. These six reflect the genotypic, phenotypic and functional characteristics of soil biodiversity. Here we review the results from the two field approaches, the first to assess the temporal sensitivity of biological indicators to key environmental pressures across a 12 month window and the second to asses the ability of biological indicators to discriminate between different habitats. We discuss the relative performance of the indicators and how these were prioritised for national-scale soil monitoring and finally, how this process has revealed new insights into the distribution and characteristics of soil biological properties within UK soils and habitats.