- Soil Science & Conservation 13
- Atmospheric Protection/Air Quality Control/Air Pollution 12
- Climate Change/Climate Change Impacts 9
- Environment, general 9
- Hydrogeology 9
- Water Quality/Water Pollution 9
- Geochemistry 4
- Biochemistry, general 3
- Climate Change 3
- Environmental Science and Engineering 3
- Environmental Chemistry 2
- Agriculture 1
- Biogeosciences 1
- Ecology 1
- Ecosystems 1
- Environmental Health 1
- Forestry 1
- Freshwater & Marine Ecology 1
- Geoecology/Natural Processes 1
- Life Sciences, general 1