Association of bacteria with soil particles. Several studies
reported a higher microbial biomass in smaller size fractions
(27, 30, 32, 58). Our results clearly demonstrated that not only
biomass, but also bacterial community structure, was signifi-
cantly affected by particle size and that smaller size fractions
host higher diversities of microbes than larger size particles.
The higher biomass in silt and clay fractions could be attributed
to a higher diversity rather than to better colonization by
particular species. This was demonstrated by comparable fluorescence
intensities of several T-RF peaks in all fractions.