similarity between biomes or sample types

Which biomes or sample types are most similar to each other? If you take a new sample (or a site sampled regularly over time that is changing), which biome/sample type does it most closely resemble.

@ElDeveloper has some code for this.

@ackermag has noted we need to make sample_type part of the metadata template. It would be great if we could find an existing ontology to use for this. I think the ENVO environmental material covers most of them, but there are some exceptions. We might need to make our own ontology that is applicable to both the EMP and American Gut.

Start by locating and reviewing the code attributed to @ElDeveloper and the metadata-template discussion about sample_type. Compare the proposed use of ENVO with EMP and American Gut requirements; the issue does not name a file, test, or acceptance criteria, so completion would require those to be established.

Written by the indexing model from the issue text.