Microcosms and microbiota activity of the methane and n (N2O) cycle under the influence of moisture in soils from Eastern Amazon

Abstract

The Amazon rainforest is considered an important biodiversity hotspot, which plays a key role in the terrestrial biosphere. Although the Amazon region maintains the largest water reservoirs in the world, contribute to climate control, precipitation and the balance of atmospheric gases flow, the Amazon rainforest is under threat of destruction due to commercial logging and farming. In this scenario, it is still unknown how anthropogenic interference will influence the microbiota and its processes in the soil. Based on the hypothesis that land use change and soil moisture alter the carbon (C) and nitrogen (N) content in the soil, and consequently affect the functional potential of the methanogenic and denitrifying microbial communities and the flux of methane and nitrous oxide in soils. Therefore, the effect of the land use change and soil moisture on the methanogenic and denitrifying microbial communities will be evaluated using soil samples collected from different study sites and obtained from a laboratory microcosm experiment with soil incubated under different moisture contents. Analytically, real-time quantitative PCR will be used to quantify the number of copies of the 16S rRNA genes from bacteria and archaea and microbial functional genes (mcrA for methanogenic and nirK, cnorB and nosZ for denitrifying bacteria) involved in the methane and nitrous oxide production, and gas chromatography will be used to determine the flux of these gases in undisturbed primary forest, secondary forest, pasture and agriculture in the Eastern Amazon region. Computational and statistical methods will be used for analysis and to integration of experimental data. The results of this research project will be disseminated at scientific events, and in the form of a scientific article to be submitted to publication in a scientific journal with editorial board. (AU)