- natural radionuclide
- natural range
- natural reactor
- natural reference frame
- natural reference system
- natural refrigerant
- natural region
- natural regionalization map
- natural regulation of population
- natural regulatory T cell，nTreg
- natural release
- natural remnant land
- natural reserve management
- natural resin
- natural resin coating
- natural resonance
- natural resource
- natural resource accounting
- Natural resource assets
- Natural resource assets auditing
- natural resource economics
- natural resource model
- natural resource optimal use theory
- natural resource pricing
- natural resource rent