The role of soil organic matter for the functionality of the soil system is complex: Organic compounds are construction materials as they provide the glue that helps to bind mineral particles together to form the basic building blocks of soil structure. Such compounds will need to stay in place for extended times to achieve their purpose. But organic compounds are also the major energy source for the microorganisms that live in the soil reactor and serve to procure and recycle resources for the ecosystem. Additionally, organic compounds are the main source of carbon and a major source of nutrients for said microorganisms. Compounds utilized as energy, carbon and nutrient sources will have to be replaced frequently as they are being spent in the process. To effectively serve its role as the recycling facility of the ecosystem, a soil will thus have to possess a static carbon component as well as a dynamic, fast flowing carbon component.
Results/Conclusions
Soil organic matter stabilization has been defined as "a decrease in the potential for SOM loss by respiration, erosion or leaching" (Sollins et al. 1996, Geoderma) and has become a widely promoted goal of land management. However, carbon needs to flow through the soil in order to maintain soil functionality. In this contribution, we will attempt to reconcile efforts to keep carbon in the soil system with the insight that "organic matter is most useful, biologically, when it decays" (Janzen 2006, Soil Biology and Biochemistry).