INBA   12521
INSTITUTO DE INVESTIGACIONES EN BIOCIENCIAS AGRICOLAS Y AMBIENTALES
Unidad Ejecutora - UE
artículos
Título:
Multivariate approach to characterizing soil microbial communities in pristine and agricultural sites in Northwest Argentina
Autor/es:
MONTECCHIA MS; CORREA OS; SORIA MA; FREY SD; GARCIA AF; GARLAND JL
Revista:
APPLIED SOIL ECOLOGY
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2011 vol. 47 p. 176 - 183
ISSN:
0929-1393
Resumen:
Land use effects on microbial communities may have
profound impacts on agricultural productivity and ecosystem
sustainability as they are critical in soil quality and health. The main
aim of this study was to characterize the microbial communities of
pristine and agricultural soils in the central Yungas region in
Northwest Argentina. As a first step in the development of biological
indicators of soil quality in this region, a comprehensive approach
involving a structural and functional evaluation of microbial
communities was used to detect changes in soil as consequence of land
use. The sites selected included two pristine montane forest sites (MF1
and MF2), two plots under sugarcane monoculture for 40 and 100 years
(SC40 and SC100), one plot under 20 years of soybean monoculture (SB20),
a recently deforested and soybean cropped site (RC), and two reference
sites of native forest adjacent to the sugarcane and soybean plots (PF1
and PF2). We used three microbial community profiling methods:
denaturing gradient gel electrophoresis (DGGE) analysis of PCR amplified
16S rRNA genes, community-level physiological profiling (CLPP) using a
BD oxygen biosensor system (BDOBS-CLPP) and phospholipid fatty acid
(PLFA) analysis. Deforestation and agriculture caused expected increases
in pH and decreases in organic carbon and microbial biomass.
Additionally, shifts in the microbial community structure and physiology
were detected with disturbance, including reduced diversity based on
PLFA data. The higher respiratory response to several carbon substrates
observed in agricultural soils suggested the presence of microbial
communities with lower growth yield efficiency that could further reduce
carbon storage in these soils.Using an integrated
multivariate analysis of all data measured in this study we propose a
minimum data set of variables (organic carbon, pH, sucrose and valeric
acid utilizations, a17:0 and a15:0 PLFA biomarkers and
the value of impact on microbial diversity) to be used for future
studies of soil quality in Northwest Argentina