Carbon stock in hydromorphic soils of the North-Eastern Part of Germany

Abstract

Changing climatic conditions in Germany mainly affect hydromorphic soils formed by groundwater. They offer comparatively high carbon contents and, as the only soil group, also accumulate C in the subsoil. The assessment of the storage capacity of these soils is essential to assign 'risk areas' according to national (German Federal Soil Protection Act, 1998) and international (EU Soil Protection Strategy, 2006) soil protection requirements. An appropriate water management enables preservation and protection of the soil organic matter in hydromorphic soils. Both aims, as a part of resource protection, require knowledge of the carbon stock of the soils and the transformation of area restricted results to a regional scale. Assessments comprise of two steps: in the first step, the carbon content of so-called horizon-substrate-combinations (HSC) for profiles of the dominant soil of a soil mapping unit is determined. This method is based on the hypothesis, that comparable soil properties are formed by equal soil substrates and pedogenetic processes. In the second step, the results are assigned to the profiles of the dominant soil of the soil mapping unit and extended to spatial polygons of functional maps. Carbon stock of hydromorphic soils is determined for the federal state Brandenburg, located in the northeast of Germany. Brandenburg is characterised by a percentage of 40 % hydromorphic soils of the country's territory and features a high vulnerability according to studies concerning climate change. The authors offer a proposal for the assignment of 'risk areas' and management principles for hydromorphic soils.