- Atmospheric Protection/Air Quality Control/Air Pollution 29
- Environmental Chemistry 17
- Math. Appl. in Environmental Science 16
- Biogeosciences 15
- Science, Humanities and Social Sciences, multidisciplinary 14
- Soil Science & Conservation 13
- Science, multidisciplinary 11
- Climate Change/Climate Change Impacts 10
- Environment, general 10
- Pollution, general 9
- Climate Change 8
- Ecotoxicology 8
- Environmental Management 8
- Hydrogeology 8
- Ecology 7
- Water Quality/Water Pollution 7
- Agriculture 6
- Environmental Health 6
- Waste Water Technology / Water Pollution Control / Water Management / Aquatic Pollution 5
- Plant Physiology 4