How to reduce the carbon footprint of the agricultural sector? Factors influencing farmers' decision to participate in carbon sequestration programs.

Mitigating climate change by sequestering carbon in agricultural soils through humus formation is a crucial component of sustainable agriculture. Humus programs that are designed to incentivize farmers to build more humus are still recent innovations, so current knowledge about farmers' motivation to participate is limited. This study examines the adoption of non-governmental humus programs to promote carbon sequestration by analyzing farmers' willingness to participate in humus programs and influential factors. We specifically investigate behavioral factors underlying farmers' adoption of humus programs using the Theory of Planned Behavior. To this end, we collected data using an online survey with 190 German farmers and applied partial least squares structural equation modeling. The results show that (i) perceived economic benefits, (ii) the actions of fellow farmers, and (iii) farmers' sense of responsibility with regard to climate change have a statistically significant influence on farmers' intention to participate in a humus program. In contrast, the perceived ecological benefits, political pressure, the possibility of establishing humus-building measures, and prior knowledge of humus programs have no statistically significant influence. Our findings suggest that farmers' decision to participate in humus programs is strongly influenced by the financial benefits, but the actions and thoughts of other farmers, as well as their own moral claims regarding climate change, also play a crucial role. We found that farmers lack knowledge about the registration and general functioning of humus programs, which can currently be one of the biggest barriers to participation in such initiatives.