field elements in meta.xml in the DarwinCore archive can contain default elements that define a static value for a term which isn't itself included in occurrence.txt.

See 2.4 in http://rs.tdwg.org/dwc/terms/guides/text/index.htm

"If no index is supplied, the default can be used to define a constant for all rows for a field that is not in the data file."

We should use a darwin core archive reader library (from HIT?).