Soil development and microbial functional diversity: Proposal for a methodological approach
Articolo
Data di Pubblicazione:
2013
Abstract:
The aimof thework was to propose a newmethodological approach that relates soilmicrobial functional diversity
to soil development under different moisture regimes. As soil evolution proceeds through an increasing niche
separation we expect a link between functional diversity and soil development. Shannon's (H') and Gini (D) diversity
indices were calculated using eight enzyme activities (β-cellobiohydrolase, N-acetyl-β-glucosaminidase,
β-glucosidase, α-glucosidase, acid phosphatase, arylsulfatase, xylosidase and butyrate esterase) in order to assess
functional diversity at different scales, from soil horizons (α-diversity) to soil profiles (β-diversity) under different
moisture regime (γ-diversity) and belonging to different taxonomic levels. In addition, the ratio of acid phosphatase
to chitinasewas calculated as a potential index of soil development. Eight soil profileswere selected: four in Northwestern
Italian Alps orNorthern Apennines with Udic soil moisture regimes (TypicHaplocryod, MollicHaplocryept,
Lithic Dystrudept, Lithic Cryorthent) and four in Northeastern Italy where in two cases the water table near the soil
surface strongly affects the Ustic soil moisture regime, and intrazonal Aquic regime or Aquic conditions develop
(Typic Haplustept, Typic Ustipsamment, Aquic Ustipsamment, Typic Psammaquent). D ranged from 50 to 95%,
while the H' ranged from 3 to 2.4 in Lithic Cryorthent and Typic Psammaquent, respectively. Under Udic moisture
regime an inverse relationship between soil profile development and the diversity index was observed. However
the lowest the diversity in the profile, the highest the variability of the values obtained within horizons in the
soil profile suggesting a link between differentiation of soil horizons and biochemical properties. The Aquic conditions
interfere in establishing the relationship between soil profile development and themicrobial functional diversity
since H' and D increased in Typic Psammaquentwith respect to Typic Haplustept (H' from 2.4 to 2.6 and D from
52.2 to 60.4). Finally, the phosphatase/chitinase ratiowas related to soil development since the lowest values were
obtained in the upper horizons of Typic Haplustept, Typic and Aquic Ustipsamment (from 2.0 to 4.0), while the
highest values were obtained in deep horizons of Typic Haplocryod and Lithic Dystrudept (e.g. 39.2 in Bs2 and
28.0 in Bw1). In conclusion, microbial functional diversity assessed using Shannon or Gini diversity indices and
phosphatase/chitinase ratio measured at different scales from soil horizons to soil profiles under differentmoisture
regime and belonging to different taxonomic levels, may represent a new approach to establish the interrelationship
between pedogenetic processes, soil development and soil microbial functions.
Tipologia CRIS:
03A-Articolo su Rivista
Elenco autori:
S. Marinari; E. Bonifacio; M.C. Moscatelli; G. Falsone; L. Vittori Antisari; G. Vianello
Link alla scheda completa:
Link al Full Text:
Pubblicato in: