You can contribute to improving data interoperability in agriculture through semantics in at least two ways:
Give your feedback to the recommendations. You can do that by contributing to the public discussion on the recommendations.
Become an adopter. You qualify as an adopter if you are actively implementing one or more of the recommendations in your initiative/projects/institutions, or if you plan on doing so in the future. You also qualify as an adopter if you endorse the general view embodied in the recommendations, even though you are not quite in an implementation phase yet. Here is a list of current adopters.