Ecological monitoring of in-situ stabilisation and fytoremediation methods: development and validation of the soil analysis package

Research Project, 2023 – 2025

Soil contamination can threaten soil organisms and thus adversely affect ecological soil functions critical for humans and ecosystems. The soil ecosystem is therefore a protected object in the Swedish risk assessment model for contaminated soils and often governs the measurable remediation targets and the extent of remediation in Sweden. In contrast to generic soil guideline values, the Soil Quality Triad approach assists in assessing site-specific risks for soil ecosystems and thus better supports remedial option appraisal. International scientific studies have demonstrated that different remediation methods can either positively or negatively impact soil microbes, nutrient retention in the soil and other important soil properties for soil functioning, however, the knowledge on impact of remediation on soil fauna is still very limited. Moreover, there is no standard minimum set of indicators for ecological monitoring of remediation methods. No field surveys have been carried out in Sweden to monitor the effects of remediation methods on soil fauna either. The aim of this feasibility study is to evaluate a package of soil fauna analyses for in-depth evaluation of innovative in-situ stabilisation and phytoremediation methods. The study is an important complement to an ongoing field trial within the scope of two research projects (funded by Formas dnr 2021-01428 and Tuffo dnr 1.1-2104-0303) and expected to fill a knowledge gap on the impact of the tested in-situ stabilisation and phytoremediation methods on soil fauna. Specific objectives of the study is to: 1) sample, extract and determine three groups of soil fauna, from the plots of the ongoing field trial; 2) compile abundance, richness and composition of soil fauna; 3) analyse effects of in-situ stabilisation and phytoremediation methods on soil fauna parameters; 4) analyse relationships between soil fauna parameters and other indicators for soil quality; 5) evaluate the selected species groups and their diversity parameters as soil quality indicators; and 6) disseminate the study results to the remediation sector.