- Man--Influence on nature (6)
- Ecology (2)
- Air--Pollution (1)
- Climatology (1)
- Ecology--Philosophy (1)
- Ecology--Political aspects (1)
- Environmental protection--Philosophy (1)
- Environmental psychology (1)
- Mental health (1)
- Mental illness--Etiology (1)
- Philosophy of nature (1)
- Population biology (1)