Impact of modified temperature and precipitation regime on soil microorganisms and carbon cycling in arable soils

点击翻译按钮获取中文摘要

Carbon cycling in terrestrial ecosystems provides a feedback mechanism to climate change by releasing or sequestering additional atmospheric CO2. However, the response of terrestrial carbon cycling to the interactive effects of a changing temperature and precipitation regime is still unclear. This project aims to relate soil organic carbon turnover under a modified climate to microbial abundance, activity and diversity. A field experiment will be established to modify temperature and precipitation on a arable field. First, we will quantify the seasonal variation of carbon mineralisation under changed climatic conditions by applying respiration, enzyme activity and microbial and fungal biomass measurements. Second, we will clarify the interactive effects of a changed litter quality and decomposition activity on litter decomposition. This will be linked to the fungal community structure by extracting, cloning and sequencing fungal DNA. Third, we will trace the litter carbon flux through the fungal and bacterial community by coupling stable isotope techniques with the extraction of bacterial and fungal biomarkers (PLFAs and ergosterol). Overall, this project will provide valuable information on the response of biogeochemical cycles to climate change and therefore will help to improve scenarios of future climate.