Within the field day "Alfalfa Cultivation and Climate Adaptation," Holger Gerdes and Zoritza Kiresiewa (Ecologic Institute) presented a draft policy paper on sustainable subsoil management in Germany. The objective was to collaboratively develop core recommendations – together with farmers, soil experts, and policy stakeholders – on how to more effectively promote deep-rooting crops, particularly alfalfa. Discussions centered on strategies for securing yields during drought years and on adapting political frameworks to make alfalfa cultivation more attractive.

How does subsoil management affect the provision of ecosystem services – and what is its economic value to society? These questions are at the heart of a study by Sophie Ittner, Holger Gerdes and Zoritza Kiresiewa from Ecologic Institute. Using a Benefit Transfer approach, the authors assess the societal costs and benefits of two subsoil management practices in German agriculture. The results demonstrate that sustainable subsoil management can generate not only ecological, but also substantial economic value – offering important insights for targeted support through agri-environmental policy.

This paper analyses relevant enabling and hindering factors for the implementation of subsoil management in a regional context, focusing on (i) geophysical conditions and (ii) relevant socio-economic criteria in selected regions of Germany.

This policy brief outlines recommendations for sustainable and socially accepted subsoil management in Germany. Subsoil, located below the plowed topsoil layer, holds essential nutrients and water reserves crucial for plant growth and sustainable bioeconomy practices. The Soil³ project (2015–2025) investigated methods to enhance subsoil usage, focusing on increasing plant root access to this layer without compromising its ecological functions.

Fertile soils are an indispensable resource for agriculture and the Bioeconomy as a whole. Subsoils contain a major part of the nutrients essential for plants, a resource potential that has thus far not yet been fully understood nor used. In order to harness this untapped potential, the Soil³ project examines the subsoil processes and application of alternative subsoil management measures. The Ecologic Institute will conduct research on the costs, benefits and social acceptance of these measures.