Biofunctool®: a new framework to assess the impact of land management on soil quality. Part A: concept and validation of the set of indicators

The assessment of soil quality is a scientific issue that has been widely debated in the literature for the last twenty years. We developed the Biofunctool® framework to assess soil quality based on an integrative approach that accounts for the link between the physico-chemical properties and the biological activity of soils. Biofunctool® consists in a set of twelve in-field, time- and cost-effective indicators to assess three main soil functions: carbon transformation, nutrient cycling and structure maintenance. The indicators were applied in a network of mostly rubber plantations compared with three other land uses in Thailand. We collected 1952 indicators values in 180 sampling points over a wide range of pedo-climatic and agronomic contexts in order to assess the validity of the indicators. A reliability, redundancy and sensitivity analysis was performed to validate the capacity of the set of indicators to assess the impact of land management on soil quality. The results showed the relevance and consistence of each of the twelve indicators to assess the soil functioning. Improvements are finally discussed to guide further implementation of the indicators in various contexts and build a soil quality index.