Useful digital soil mapping products for farmers

In large parts of Switzerland, there are up to the present day no soil maps in a more precise scale than 1:25’000. In 2020 the Swiss government adopted a soil strategy to promote soil mapping and the required tools and guidelines. Furthermore, authorities are legally obligated to delineate areas for the high-quality arable land inventory. In the future, soil maps will be available at high resolution for increasingly large areas. However, farmers are not used to work with this type of soil information as it was so far not available and data products are unknown.

In a pilot study of 1’000 ha in the canton of Bern a large number of soil properties have been mapped at high resolution using digital soil mapping techniques based on 1’500 newly surveyed observations. The content of the maps ranges from continuous or classified basic soil properties such as texture or soil organic matter content to aggregated soil properties such as water storage capacity. From these baseline maps certain applications and examples were assessed for specific agricultural use and the corresponding maps were discussed with local farmers. The examples include options for precision farming, proposals for new sampling sites for the legally required soil survey, the generation of more meaningful routine measurements and planning bases for irrigation systems at regional scale. Feedback was diverse and interest in soil maps differs largely according to farm management, specialization and digital affinity. Our study shows the importance of stakeholder involvement and training as well as familiarization of the farmers with digital soil maps.