I see two possible use case
one focus on document and information ressource exchange able to adapt
at different domain (agriculture, agronomie, cooker and so on) and
granularity
so it is a document management use case.
one focus on spatio temporal data integration based on observation (crop
observation, species observation)...
Thus for example some comparaison, integration, search aggregation issue
should be presented.
it is a data management use case.
This first one seems simpler to explain (because you did not need to go
in the document); There is only one common schema to express the
document metadata.
the second is a little bit more complicated because you need to take in
account the data schema that may be really different (scope, granularity
and so one).
the second need the output of the first but the two type of systems are
really differents...
Best
Catherine