Effects of prescribed fires on bacterial communities of savanna soils from Cerrado region
Silva, Universidade de Brasília, firstname.lastname@example.org
Bresolin, EMBRAPA-CPAC, email@example.com
Bustamante, Universidade de Brasília, firstname.lastname@example.org
Kruger, Universidade Católica de Brasília, email@example.com
Reis Jr., EMBRAPA-CPAC, firstname.lastname@example.org
The functioning of Cerrado ecosystems may be altered by the replacement of vegetation cover and fire to convert native areas to pasture. Soil microbial communities could be used as indicator of soil changes and consequences on nutrient turnover and gas emissions from soil to atmosphere. The objective of this work was to determine the effects of prescribed fires in native Cerrado areas on soil bacterial communities. Native areas are located at Reserva Ecológica do Instituto Brasileiro de Geografia e Estatística (RECOR/IBGE), in Brasília, DF. The native areas have been subjected to prescribed fires since 1992 every two years at the end of dry season (September) and the last fire was in 2002. Soils samples (0 - 5 cm) were taken from June/2002 to June/2003. Microbial biomass (fumigation-incubation method), soil moisture and pH were higher in unburned native areas than in burned native areas. Denaturing Gradient Gel Electrophoresis (DGGE) was used to analyze the diversity of the soil bacterial communities from native cerrado soils. Samples for DDGE analysis were collected from wet and dry season, transitions between seasons and after prescribed fires. There were no differences in DGGE profiles from unburned and burned soils from native areas after the prescribed fire. The seasonality was the main factor to differentiate bacterial communities.
Science Theme: LC (Land Use and Land Cover Change)