Nature priority areas

Words matter, not only because of their dictionary meaning, but also because of their association. The word 'protected' is a major communication issue because of its negative associations: restriction, limits on my personal freedom, prohibition of activities that we always traditionally undertook here etc. A global campaign to raise support for parks and protected areas may therefore not be taken serious by the intended audiences. The word conservation areas is already better, although associated maybe too much with 'conservative' and 'exclusiveness' and not vey useful in many developing countries. 

I would go for positioning protected areas and parks as “nature priority areas” or something like that. Or look for other ways to convey the message that commercial use, industrial zoning and urbanization needs to take place in  some places, but nature must have some degree of priority in other places. The extent of that priority can vary e.g. as described in the WCPA categories.