terra preta  soils were likely formed between 500 and 2500  years ago by pre - columbian populations . these soils are found in the amazonian region distinguished by the presence of ceramic artifacts , animal bones and high amounts of charred organic materials , which are commonly referred as black carbon ( bc ) . ade soils are considered as model soils because their high chemical fertility ( high content levels of organic c , p , ca , mg , zn , and mn ) and stable organic matter . also , ade soils are characterized by their distinct microbial communities , with a higher diversity and richness when compared to the surrounding soils . the aim of this study was to investigate the taxonomic and functional diversity of two ade sites based on metagenomic approach . soils were collected in the hatahara site located in the municipality of iranduba ( 0316494s 6012340w ) , in the amazonas state , brazil . dna extraction from 250  mg of soil was carried out using powersoil dna isolation kit ( mobio laboratories , carlsbad , ca , usa ) , according to the manufacturer 's protocol . dna quality and concentration were measured by agarose gel electrophoresis and nanodrop 1000 spectrophotometer ( thermo scientific , waltham , ma , usa ) . soil dna samples were used to prepare paired - end libraries ( 2    300  bp ) using the miseq reagent kit v.2 ( 500  cycles ; illumina , san diego , ca , usa ) , for further shotgun metagenomic sequencing in a miseq personal sequencing system ( illumina , san diego , ca , usa ) . a total of 3,716,966 paired - end and non - paired forward sequences ( average length of 241  bp ) were joined using the pear software . metagenomic sequences were annotated using the mg - rast automatic annotation server ( . ) . exploratory data analysis was conducted in stamp software . the most abundant phyla detected were proteobacteria ( 40    2% ) , actinobacteria ( 18    1% ) , firmicutes ( 5    0.3% ) and acidobacteria ( 4    0.5% ) . others phyla detected were planctomycetes ( 3.5 0.4% ) , chloroflexi ( 2.5    0.3% ) , cyanobacteria ( 2.5    0.1% ) , bacteroidetes ( 2    0.2% ) and verrucomicrobia ( 2    0.2% ) . the archaea diversity was represented by the phyla crenarchaeota , euryarchaeota , korarchaeota , nanoarchaeota and thaumarchaeota , with approximately 1.5    0.5% of total abundance . protein annotations were grouped into functional categories and the most abundant functions were related to carbohydrates ( 15    0.5% ) , clustering - based subsystems ( 14    0.2% ) , aminoacids ( 11    0.16% ) , miscellaneous ( 7    0.03% ) and protein metabolism ( 6    0.16% ) . the most abundant category level 3 is associated with serine - glyoxylate cycle ( 1.8    0.5% ) . we hypothesize that these functions are related to methylotrophs and methane reducing on ade soils , but further studies are necessary to validate this inference . our dataset reveals a great taxonomic and functional microbial potential to be explored by bioprospecting of new enzymes or identifying unknown microorganisms . terra preta  soils were likely formed between 500 and 2500  years ago by pre - columbian populations . these soils are found in the amazonian region distinguished by the presence of ceramic artifacts , animal bones and high amounts of charred organic materials , which are commonly referred as black carbon ( bc ) . ade soils are considered as model soils because their high chemical fertility ( high content levels of organic c , p , ca , mg , zn , and mn ) and stable organic matter . also , ade soils are characterized by their distinct microbial communities , with a higher diversity and richness when compared to the surrounding soils . the aim of this study was to investigate the taxonomic and functional diversity of two ade sites based on metagenomic approach . soils were collected in the hatahara site located in the municipality of iranduba ( 0316494s 6012340w ) , in the amazonas state , brazil . dna extraction from 250  mg of soil was carried out using powersoil dna isolation kit ( mobio laboratories , carlsbad , ca , usa ) , according to the manufacturer 's protocol . dna quality and concentration were measured by agarose gel electrophoresis and nanodrop 1000 spectrophotometer ( thermo scientific , waltham , ma , usa ) . soil dna samples were used to prepare paired - end libraries ( 2    300  bp ) using the miseq reagent kit v.2 ( 500  cycles ; illumina , san diego , ca , usa ) , for further shotgun metagenomic sequencing in a miseq personal sequencing system ( illumina , san diego , ca , usa ) . a total of 3,716,966 paired - end and non - paired forward sequences ( average length of 241  bp ) were joined using the pear software . metagenomic sequences were annotated using the mg - rast automatic annotation server ( . ) . exploratory data analysis was conducted in stamp software . the most abundant phyla detected were proteobacteria ( 40    2% ) , actinobacteria ( 18    1% ) , firmicutes ( 5    0.3% ) and acidobacteria ( 4    0.5% ) . others phyla detected were planctomycetes ( 3.5 0.4% ) , chloroflexi ( 2.5    0.3% ) , cyanobacteria ( 2.5    0.1% ) , bacteroidetes ( 2    0.2% ) and verrucomicrobia ( 2    0.2% ) . the archaea diversity was represented by the phyla crenarchaeota , euryarchaeota , korarchaeota , nanoarchaeota and thaumarchaeota , with approximately 1.5    0.5% of total abundance . protein annotations were grouped into functional categories and the most abundant functions were related to carbohydrates ( 15    0.5% ) , clustering - based subsystems ( 14    0.2% ) , aminoacids ( 11    0.16% ) , miscellaneous ( 7    0.03% ) and protein metabolism ( 6    0.16% ) . the most abundant category level 3 is associated with serine - glyoxylate cycle ( 1.8    0.5% ) . we hypothesize that these functions are related to methylotrophs and methane reducing on ade soils , but further studies are necessary to validate this inference . our dataset reveals a great taxonomic and functional microbial potential to be explored by bioprospecting of new enzymes or identifying unknown microorganisms .