- Soil Science & Conservation 24
- Agriculture 20
- Ecology 19
- Plant Physiology 18
- Plant Sciences 18
- Atmospheric Protection/Air Quality Control/Air Pollution 3
- Climate Change/Climate Change Impacts 2
- Environment, general 2
- Hydrogeology 2
- Water Quality/Water Pollution 2
- Computer Appl. in Life Sciences 1
- Processor Architectures 1
- Sedimentology 1
- Terrestial Ecology 1
- Waste Management/Waste Technology 1
- Waste Water Technology / Water Pollution Control / Water Management / Aquatic Pollution 1