Project description B6

Scientific advisor


Project
Compound specific isotope ratios to trace carbon and nitrogen flow in diversity clusters

The sub-project B6 investigates the effect of various tree species composition on the diversity of microorganisms in the soil with analyses of phospholipid fatty acids (PLFA’s). For this purpose soil samples were collected from 100 diversity clusters, consisting of three tree individuals representing various combinations of five tree species abundant in the Hainich forest. Furthermore, in cooperation with the sub-projects A1 (Jasmin Weiße), A4 (Verena Eißfeller) and B5 (Christina Langenbruch) leaf litter, labelled with 13C and 15N, will be exposed in an external label-experiment. During this experiment the carbon and nitrogen flow will be traced and involved microbial communities in the soil investigated. To get more information about the community structure of the microorganisms stable isotope probing (SIP) will be combined with the presence of functional enzymes. This permits to link changes in microbial diversity to changes in ecosystem functions.

Methods


  • extraction of phospholipid fatty acids (PLFA’s) from soil samples as biomarkers for microbial communities
  • gas chromatography and mass spectrometry for quantification and classification
  • stable isotope studies on PLFA-profiles (13C, 15N)
  • stable isotope probing (SIP)