Qualitative and Quantitative Changes in Soil Organic Compounds in Central European Oak Forests with Different Annual Average Precipitation

The various climate scenarios consistently predict warming and drying of forests in Hungary. Soils play a significant role the long-term sequestration atmospheric CO2, while other cases they can also become net carbon emitters. Therefore, it is important to know what be expected regarding future changes storage capacity soils forests. We used precipitation gradient studies solve this problem, using type “space–time” substitution. In research, we primarily examined quality parameters soil organic matter (SOM) investigate how change transforms ratio main SOM compound groups soils. For our studies, applied elemental 13C 15N isotopic analysis, NMR FT-IR spectra thermogravimetric differential thermal analyses measure chemistry samples from different oak with contrasting mean annual Central Europe. Our results showed that (SOC) was lower humid due enhanced decomposition processes leaching Ca, which stabilizes SOM; however, particular, amount easily degradable compounds (e.g., thermolabile SOM, O-alkyl carbon, carboxylic carbonyl carbon) decreased. dry forest soils, recalcitrant thermostable alkyl aromatic phenolic organo–mineral complexes stabilized by Ca increased, but increased further. conclusion study SOC increase drier, compensating somewhat for decrease plant biomass.