Humboldt-Universität zu Berlin - Ecology

Carbon flux through the soil animal food web

The project is part of the DFG Research Unit "Carbon flow in belowground food webs assessed by isotope tracers" (FOR 918)



The Research Unit FOR 918 investigates the carbon flux through biotic soil compartments. Field experiments are performed at an agricultural site with permanent C3 crop, where a 13C signal is introduced by cultivating the C4 plant Zea mays. Carbon assimilation and partitioning in the major energy pathways based on roots, bacteria or fungi are assessed, taking into consideration factors such as resource quality and availability as well as food web complexity.





 
FOR
       


     Depth gradient 
Nematode community assessment
Soil depth transect


The present project applies isotope tracer methods for identification of key biota and quantification of the carbon flux in the trophic cascade. This includes the incorporation of 13C label into soil animals as well as specific biomarker lipids, to ascribe species to trophic levels and to identify major food resources. In the rhizosphere and detrital based topsoils the availability of resources (recalcitrant/labile) to Nematodes, and their role in sequestration and transfer, is estimated. Additionally a gradient from this resource rich to deeper oligotrophe habitats with low diverse food webs is investigated.




PhD students harvesting maize

PhD students Anika Scharroba and Christopher Ngosong
at maize harvest.