| adapters | optional |
| amount or size of sample collected | optional |
| annotation source | optional |
| broad-scale environmental context | mandatory |
| chimera check | optional |
| composite design/sieving (if any) | optional |
| current land use | optional |
| current vegetation | optional |
| current vegetation method | optional |
| drainage classification | optional |
| encoded traits | optional |
| environmental medium | mandatory |
| estimated size | optional |
| experimental factor | optional |
| extrachromosomal elements | optional |
| extreme_unusual_properties/Al saturation | optional |
| extreme_unusual_properties/Al saturation method | optional |
| extreme_unusual_properties/heavy metals | optional |
| extreme_unusual_properties/heavy metals method | optional |
| extreme_unusual_properties/salinity | optional |
| extreme_unusual_properties/salinity method | optional |
| finishing strategy | optional |
| geographic location (altitude) | optional |
| geographic location (depth) | mandatory |
| geographic location (elevation) | mandatory |
| geographic location (latitude) | mandatory |
| geographic location (longitude) | mandatory |
| geographic location (region and locality) | optional |
| health or disease status of specific host | optional |
| history/agrochemical additions | optional |
| history/crop rotation | optional |
| history/extreme events | optional |
| history/fire | optional |
| history/flooding | optional |
| history/previous land use | optional |
| history/previous land use method | optional |
| history/tillage | optional |
| horizon | optional |
| horizon method | optional |
| investigation type | ignore |
| isolation and growth condition | optional |
| known pathogenicity | optional |
| library construction method | optional |
| library reads sequenced | optional |
| library screening strategy | optional |
| library size | optional |
| library vector | optional |
| link to classification information | optional |
| link to climate information | optional |
| links to additional analysis | optional |
| local environmental context | mandatory |
| mean annual and seasonal precipitation | optional |
| mean annual and seasonal temperature | optional |
| microbial biomass | optional |
| microbial biomass method | optional |
| miscellaneous parameter | optional |
| multiplex identifiers | optional |
| nucleic acid amplification | optional |
| nucleic acid extraction | optional |
| number of replicons | optional |
| observed biotic relationship | optional |
| pcr conditions | optional |
| pcr primers | optional |
| perturbation | optional |
| pH | optional |
| pH method | optional |
| ploidy | optional |
| pooling of DNA extracts (if done) | optional |
| profile position | optional |
| project name | ignore |
| propagation | optional |
| reference for biomaterial | optional |
| relationship to oxygen | optional |
| relevant electronic resources | optional |
| relevant standard operating procedures | optional |
| sample collection device or method | optional |
| sample material processing | optional |
| sample volume or weight for DNA extraction | optional |
| sample weight for DNA extraction | optional |
| sequence quality check | optional |
| sequencing method | ignore |
| slope aspect | optional |
| slope gradient | optional |
| soil type | optional |
| soil type method | optional |
| soil_taxonomic/FAO classification | optional |
| soil_taxonomic/local classification | optional |
| soil_taxonomic/local classification method | optional |
| source material identifiers | optional |
| specific host | optional |
| storage conditions | optional |
| subspecific genetic lineage | optional |
| target gene | optional |
| texture | optional |
| texture method | optional |
| total nitrogen | optional |
| total nitrogen method | optional |
| total organic C method | optional |
| total organic carbon | optional |
| trophic level | optional |
| water content | optional |
| water content method | optional |
