Cost of increasing soil organic matter in specialty crops

Background and Objective

To disseminate measures that build-up and preserve humus in agricultural and horticultural soils, the German Ministry of Agriculture is funding model and demonstration projects (MuD) as part of the Climate Protection Programme 2030 (Klimaschutzprogramm 2030). Since summer 2024, four MuDs – HumusFürGemüse, ClimateApples, CarboVino und HumusHopfen – involving approximately 100 farms across 14 major cultivation regions in Germany have been established. In addition, SK Hum accompanies the MuDs scientifically in the implementation of farm-specific measures.

In close cooperation with the four MuDs, the SK Hum project partners, Julius Kühn Institute and Thünen Institute, will evaluate the measures’ effectiveness, economic efficiency and their contribution to climate mitigation. Specifically, the project will

• develop and evaluate various measures to increase and maintain humus in cropping soils,
• quantify the humus build-up and evaluate the climate protection performance of these measures,
• assess the associated economic consequences and identify factors that promote or hinder implementation,
• estimate future developments and draw up generalisable statements on the effects of implementing these measures on production costs and profitability, and
• derive recommendations for stakeholders from practice, extension, research and politics to promote humus build-up in vegetable, apple, wine, and hop production.

Approach

A coordinated data collection and data analysis, focussing on a standardised procedure for determining soil humus content, is essential to make data comparable across all four MUDs and to have transferable results. In addition, close cooperation with the project HumusKlimaNetz, which analyses the humus build-up in arable farming, will ensure the surveys and analysis from arable crops are directly comparable to those from vegetable, apple, wine, and hop production.

A catalogue of possible measures for humus management will be developed as a basis for humus and climate balancing as well as for socio-economic analysis. This catalogue should already contain evaluations of the measures’ influence on crop production. Subsequently, the humus build-up and greenhouse gas emissions in the demonstration areas will be balanced and their economic efficiency will be analysed.

All results from SK Hum and the four MuDs will contribute to the final tasks of technology assessment and SWOT analysis, which will lead to the development of recommendations for agricultural and horticultural stakeholders.

The research findings from four MUDs will be disseminated through specific field days for farmers, presentations at conferences for advisors and articles in crop production journals to ensure the transfer of knowledge to agricultural and horticultural practice.

Data and Methods

Thünen Institute is working on the economic aspects within the SK Hum project. With farm-specific data surveys in participating farms, literature analysis, focus group discussions, and workshops with experts, the production of vegetables, apples, wine, and hops will be analysed through

• farm individual cost accounting and cost-benefit analysis: Evaluating measures to build-up and conserve humus,
• cost and risk analysis: Assessing typical production systems for apple, wine, and hop, as well as typical crop rotations in vegetable production with a focus on humus building, and
• sector analysis, technology assessments and SWOT analysis: Analysing these measures in vegetable, apple, wine, and hop production.

Our Research Questions

• What kind of costs and benefits are associated with vegetable, apple, wine, and hop production with the implementation of different measures to build up or preserve humus content in the soil?
• What general economic findings can be obtained from the costs and benefits of measures that promote humus increase in soils?
• What opportunities and risks do these measures present for vegetable, apple, wine, and hop production?