%0 Journal Article
%A Hünninghaus, Maike
%A Koller, Robert
%A Kramer, Susanne
%A Marhan, Sven
%A Kandeler, Ellen
%A Bonkowski, Michael
%T Changes in bacterial community composition and soil respiration indicate rapid successions of protist grazers during mineralization of maize crop residues
%J Pedobiologia
%V 62
%@ 0031-4056
%C München
%I Elsevier
%M FZJ-2017-03789
%P 1 - 8
%D 2017
%X Decomposition of organic matter is crucial for ecosystem functioning. Microorganisms, which areresponsible for the mineralization of organic matter, are usually treated as a homogeneous functionalguild, despite mineralization capacity can differ profoundly between taxa. In addition, a significant partof the microbial community is top-down controlled by microbial grazers, such as protist. Since protistgrazing is selective, and selectivity differs among species, we hypothesized that protist taxa complementeach other in grazing intensity and thereby affect bacterial community structure and mineralization rate.In a laboratory experiment the species richness of protist communities was manipulated in an arable fieldsoil and the mineralization rate of maize litter residues followed during the decomposition of the labile(4 days) and recalcitrant (3 weeks) carbon (C) fractions. Mineralization rate overall increased in thepresence of protists. Changes in microbial function could be related to changes in microbial communitycomposition (measured by phospholipid fatty acids pattern). During microbial decomposition, differentprotist grazers gained influence on mineralization rates over consecutive time intervals, indicating that asuccession of protists caused an enhanced bacterial C-mineralization of plant detritus. Protist identityand species richness affected the microbial community composition, but not the magnitude of itsmineralization function. In general, protist identity appeared to be more relevant for the composition ofthe microbial communities at the beginning of decomposition while the protist species richnessappeared to be more critical in the later, slow phase of decomposition. This study provides an examplethat the overall outcome of ecosystem processes, such as mineralization rate is regulated by the sum ofpositive and negative effects of complex species interactions operating at a very fine spatial and temporalscales.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000403634700001
%R 10.1016/j.pedobi.2017.03.002
%U https://juser.fz-juelich.de/record/830215