- Sustainable Development 16
- Environmental Management 12
- Climate Change Management and Policy 10
- Atmospheric Sciences 8
- Environment, general 8
- Environmental Engineering/Biotechnology 8
- Monitoring/Environmental Analysis 8
- Climate Change 7
- Earth System Sciences 7
- Environmental Science and Engineering 7
- Geochemistry 6
- Atmospheric Protection/Air Quality Control/Air Pollution 5
- Pollution, general 5
- Waste Water Technology / Water Pollution Control / Water Management / Aquatic Pollution 5
- Environmental Economics 4
- Environmental Health 4
- Industrial Chemistry/Chemical Engineering 4
- Natural Resource and Energy Economics 4
- Asian Politics 3
- Atoms and Molecules in Strong Fields, Laser Matter Interaction 3