respectively)that were highestin disturbed soil profiles, regardless
of depth (Table 4). However, dehydrogenase, phosphatase and
arylsulphatase specific activities were the highest in the deepest
layer (100–120 cm) of disturbed soils or the deepest horizon (C) of
undisturbed ones (except for dehydrogenase) compared to the
upper layers or horizons.
Microbial community structure assessed by PLFAs showed
significant differences between undisturbed and disturbed topsoils
if expressed on soil weight basis (Table 5, A horizon vs.
0–20 cm layer, respectively). Total PLFAs, as well as those in
bacteria and fungi, were at least thrice higher in undisturbed
topsoils compared to disturbed ones. Moreover, the ratio fungi/
bacteria (F/B) was more than twice, whereas the ratio G/G+
bacteria was less than half in undisturbed topsoils compared to
disturbed ones. With PLFAs expressed on TOC mass basis, both
total and group-specific PLFAs unexpectedly seemed to become
higher in disturbed than undisturbed topsoils, but truly there was
no significant difference between them since CVs were always
highest (>70%) in disturbed topsoils, once again confirming the
increased spatial variability due to the profile dismantlement.
Moreover, the extremely low TOC content on whole soil mass basis
surely contributed to the outward increase of PLFAs in disturbed
topsoils when expressed on TOC mass basis.
As a general rule, dismantlement of soil profile in disturbed
soils was evident by much higher CVs for all measured
bioindicators compared to undisturbed ones, regardless of either
whole soil or TOC mass basis. Moreover, except for PLFAs,
bioindicators expressed on TOC mass basis, as expected, had
lower CVs than on whole soil mass basis.