- Ecology 19
- Environmental Management 18
- Freshwater & Marine Ecology 13
- Atmospheric Protection/Air Quality Control/Air Pollution 10
- Coastal Sciences 10
- Hydrogeology 10
- Landscape Ecology 7
- Environment, general 6
- Ecotoxicology 5
- Monitoring/Environmental Analysis 5
- Water Quality/Water Pollution 4
- Forestry Management 3
- Hydrology/Water Resources 3
- Nature Conservation 3
- Waste Water Technology / Water Pollution Control / Water Management / Aquatic Pollution 3
- Water and Health 3
- Climate Change/Climate Change Impacts 2
- Conservation Biology/Ecology 2
- Environmental Law/Policy/Ecojustice 2
- Marine & Freshwater Sciences 2