chapter  13
30 Pages

Greenhouse Gases, Nile Snails, and Human Choice

WithGilbert F. White

The study of environmental behavior is focused on human activities, as well as attitudes and knowledge, that either affect or are affected by other components of their environment. In the long history of human alterations of the face of the earth, the period after World War II was unprecedented in the magnitude, complexity, and speed of the transformations on all continents. Humans are usually exposed when drawing water, bathing, or working with irrigation water in which the cercariae conduct their torpedolike attacks. Geographers are accustomed to dealing systematically with the interaction of certain complex factors, such as atmospheric pollutants and public regulations, but even they have tended to handle human and physical factors separately. Schistosomiasis is transmitted by a cycle of eggs carried in feces or urine to a gently flowing water environment suitable for a host snail such as Bulinus or Biomphalaria.