- Ecology 4
- Environmental Health 4
- Plant Sciences 4
- Animal Ecology 3
- Ecotoxicology 3
- Entomology 3
- Life Sciences, general 3
- Atmospheric Protection/Air Quality Control/Air Pollution 2
- Biodiversity 2
- Conservation Biology/Ecology 2
- Environment, general 2
- Environmental Chemistry 2
- Environmental Science and Engineering 2
- Pharmacology/Toxicology 2
- Pollution, general 2
- Behavioral Sciences 1
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- Effects of Radiation/Radiation Protection 1
- Evolutionary Biology 1
- Forestry 1