Unless I’m missing something, “Observations Fields” data for iNat observations is currently not included in the DarwinCore file that is exported to GBIF. This is unfortunate, considering the potential utility of this data for researchers who may primarily retrieve iNat data through GBIF.
I personally have utilized iNat data for trait analyses in fungi. To do this, I mined the “occurrenceRemarks” field of the DarwinCore file (this field currently only contains data from the “Notes” section of each iNat observation) for substrate-related keywords or phrases (e.g., “on wood”, “on soil”, etc.). Unfortunately, many iNat users do not add any information to the “Notes” field when they make an observation, which means the corresponding “occurrenceRemarks” value in the DarwinCore file will be blank and the observation will ultimately not be usable. In this scenario, “Observation Fields” data may revive the utility of these observations, since this data can be added by other users, such as myself. For example, if I was feeling ambitious and wanted to expand the number of useful observations in my data set, I could start adding substrate-relevant observation field data to records that had no “Notes” information or information that was not substrate-relevant. I don’t know if other research fields would similarly benefit from this data being added to the DarwinCore file, but it would immediately have significant utility in my work with fungi.
In terms of adding this data to the “occurrenceRemarks” field, perhaps it could be appended to the “Notes” data that may already be present in that field. There are likely much better ways to format this, but the string could look something like this:
Notes: found growing on wood. Fungus substrate (observation field): wood.
Where “Fungus substrate” is a type of observation field.
I don’t know as much about iNat “Annotations”, since they don’t currently have any utility for fungi (as far as I can tell), but perhaps they could ultimately be added to the “occurrenceRemarks” field of the DarwinCore file as well.