Search

Along with the development of citizen sciences, an increasing number of initiatives concerning soils are emerging. Soils are key components of ecosystems and original objects for citizen sciences since they integrate the multiple impacts of human activities (agroecology, biodiversity, food, climate). This article presents an analysis of 20 on-going projects in France. It is based on a questionnaire circulated to the project leaders, regarding i) properties, use context and co-building processes between the actors of research and of society, ii) lessons learned from a conference associating the actors involved in these projects, on the needs, outputs for research and for society, difficulties and successes, and potential pooling between projects. This first conference on soil citizen sciences, which gathered some one hundred participants, may hopefully boost exchanges between projects and lead to developing a national network of actors concerned. [ABSTRACT FROM AUTHOR]

• Global, national and regional digital soil mapping products were evaluated in three contrasting regions of France. • Conventional soil maps and punctual information were used as references. • The regional DSM products outperformed the national product, which outperformed the global product. • At local scale, none of the tested DSM products provided satisfactory predictions. • Users should be informed of the potential and limitations of DSM products. As digital soil mapping (DSM) applications have been developed at multiple extents over the two last decades, large areas of the world are now covered by several DSM products with similar resolution and targeted soil properties. Thus, from these products, end-users must carefully select the one that will best meet their needs. The aim of this study was to evaluate three DSM products obtained at different scales (global, national and regional) over three local territories of increasing area selected in three contrasting regions of France (Alsace, Brittany and Languedoc-Roussillon). Three topsoil (5–15 cm) properties were evaluated: clay content, pH in water and soil organic carbon content. Evaluations were done at both point and soil mapping unit supports, the latter corresponding to quantitative assessment of visual accordance between DSM products and conventional local soil maps of acknowledged quality. The ability to predict soil properties well increased from global to national to regional DSM products. However, none of the DSM products tested was able to predict satisfactorily at the most local (1:25,000) scale. Evaluations of DSM products using local soil maps were generally in accordance with those using points. Evaluations using local soil maps also provided additional information about the utility of DSM products for small areas with too few soil measurements to perform punctual evaluation and for issues concerning areal-support uses of DSM products. These results suggest that when focusing on local areas, users of DSM products should evaluate their performance and, if unsatisfactory, invest in development of local DSM. [ABSTRACT FROM AUTHOR]