The bacterial energy channel: Protozoa-bacteria interrelationships as affected by root vicinity, organic matter and soil depth

• Applicant: Professor Dr. Michael Bonkowski
• Subject Area: Microbial Ecology and Applied Microbiology ; Soil Sciences
• Term: from 2008 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 40526089

The project investigates the carbon (C) flux through the bacterial channel of the decomposer food web. The density and community structure of protozoa along two gradients of a maize field will be investigated: (1) from the rhizosphere to bulk soil and (2) from upper to deeper soil layers. Additionally a new field experiment will be set up to separate rhizosphere and detritusphere C inputs, and to identify herbivore links with the root energy channel. Laboratory experiments will be performed to identify trophic links and to quantify C fluxes in the microbial loop between bacteria and protozoan taxa in the rhizosphere and detritusphere and changes in link strength during detritus decomposition. Laboratory experiments will further identify herbivore links with the bacterial energy channel. It is hypothesized that protozoa are key-players in controlling the flux of C through bacteria in the rhizosphere, detritusphere, and particularly at deeper soil layers.

• DFG Programme: Research Units
• Subproject of: FOR 918: Carbon Flow on Belowground Food Webs Assessed by Isotope Tracers
• Participating Person: Dr. Robert Koller