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.
respectively)that were highestin disturbed soil profiles, regardlessof depth (Table 4). However, dehydrogenase, phosphatase andarylsulphatase specific activities were the highest in the deepestlayer (100–120 cm) of disturbed soils or the deepest horizon (C) ofundisturbed ones (except for dehydrogenase) compared to theupper layers or horizons.Microbial community structure assessed by PLFAs showedsignificant differences between undisturbed and disturbed topsoilsif expressed on soil weight basis (Table 5, A horizon vs.0–20 cm layer, respectively). Total PLFAs, as well as those inbacteria and fungi, were at least thrice higher in undisturbedtopsoils 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 todisturbed ones. With PLFAs expressed on TOC mass basis, bothtotal and group-specific PLFAs unexpectedly seemed to becomehigher in disturbed than undisturbed topsoils, but truly there wasno significant difference between them since CVs were alwayshighest (>70%) in disturbed topsoils, once again confirming theincreased spatial variability due to the profile dismantlement.Moreover, the extremely low TOC content on whole soil mass basissurely contributed to the outward increase of PLFAs in disturbedtopsoils when expressed on TOC mass basis.As a general rule, dismantlement of soil profile in disturbedsoils was evident by much higher CVs for all measuredbioindicators compared to undisturbed ones, regardless of eitherwhole soil or TOC mass basis. Moreover, except for PLFAs,bioindicators expressed on TOC mass basis, as expected, hadlower CVs than on whole soil mass basis.
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