We use cookies on our website. Some are necessary for the operation of the website. You can also allow cookies for statistical purposes. You can adjust the data protection settings or agree to all cookies directly.
Data Protection Declaration
Imprint
SPP 1090 AG 1: Quantity, composition and turnover of organic matter in subsoils
Project
Project code: DFG SPP 1090
Contract period: 01.01.2000
- 01.01.2008
Purpose of research: Basic research
Knowledge about the quantity, composition and turnover of the organic matter in soils of temperate regions is mainly limited to the topsoil (A horizons and litter layers), where the highest soil organic matter (SOM) concentrations are found. However, recent carbon inventories have shown that significant amounts of SOM at low concentrations are stored in the subsoil. The aims of this study are (1) to determine the amount of SOM present in subsoils, (2) to examine its composition and origin and (3) to analyse its turnover. With these findings, the stabilisation mechanisms of SOM in subsoils will be elucidated. The conceptual approach includes a carbon inventory with determination of the radiocarbon age of soil profiles at the study sites of the priority program. The composition of SOM will be studied by CPMAS 13C NMR spectroscopy. The origin of stabilised SOM compounds such as above- and belowground plant and microbial residues will be investigated, using the lipid, polysaccharide and lignin fraction as tracers. Decomposition studies under controlled laboratory conditions and the determination of the radiocarbon age of the CO2 released will give information about the turnover of 'young' and 'old' C in subsoils. Interpretation of the results will include the entire depth of the soil profile, and will be related to information on the surface soils as well as to findings of other research groups in the priority program. The properties of SOM in subsoils and the regulation of its turnover will be studied in the following phases of the priority program.
Section overview
Subjects
- Soil science
