includes: Ozone, acid rain, photochemical smog, nitrogen dioxide, sulphuric acid, these are discussed in the essay. The essay made use of material in the Open Educational Resources (OERs). The OERs are defined as any educational material found in the public domain which allows any use to freely copy, share adapt and reshape. This includes: lecturer notes, assignments, videos, textbooks. Thus this essay was written after consultation of various sources. Different secondary pollutants were identified,
widely used by most historians and social scientists, wherein society can be divided into four broad bands – the economy, the polity, social structure and culture. Essentially, he adds a fifth category to this scheme – the ecological infrastructure – soil, water, flora and fauna, etc. Juxtaposing this to the earlier four categories, gives the “five-fold