Humus content on arable land in Schleswig-Holstein and its potential as carbon reservoirs
Humus consists of dead organic soil substance. It serves as a nutrient reservoir and is therefore an important structural element for agricultural use and soil fertility. Furthermore, humus functions as a carbon reservoir for terrestrial ecosystems. A change in humus content subsequently results in CO2 emissions or CO2 fixations. It is a time-consuming process and requires substantial changes in management processes. After a while, the amount of humus is usually in balance, depending on the cultivation, the parent rocks and the climate. In the past, it was assumed that changes in organic fertilisation and soil cultivation especially offers great potential for carbon reservoirs. However, exact and current details about humus concentration in soils in Schleswig-Holstein and its development over time cannot be provided. For this purpose, it is not possible to provide profound forecasts for the evaluation of the current and possible potential for CO2-storage of arable land in Schleswig-Holstein.
According to §9 of the Energy Transition and Climate Protection law in Schleswig-Holstein from 7th March 2017, the state government is legally bound to promote the preservation and cultivation of humus for soils in terrestrial ecosystems through appropriate measures. The first step in 2021 to meet the goals of the law and to predict the potential for carbon reservoirs in arable lands in Schleswig-Holstein is the required estimation of the humus concentration in different soil types (topsoil and subsoil). Secondly (in 2022), missing locations without current data will be included and sampled additionally. Simultaneously, it will be possible to assess the chronological development of selected locations, according to the available data records. Only then can it be guaranteed to provide a precise forecast of the actual potential for carbon reservoirs on arable lands in Schleswig-Holstein.