The first plant communities as can be seen from the pollen graphs in this book were impoverished in species. The Permian era started with a very cold climate and as the climate warmed more and more diverse vegetation took hold. The emergence of different forms of pollen at certaintimes in the Permian is used as an indicator of climatic change. Furthermore, the predominance of algal spores in some samples and lack of representation by pollen of Glossopteris point to significant changes in the climate which led to the disappearance of their pollen and the accumulation of spores representing algal communities. These climate induced changes are noticed in their completed transformation after a long time span; small changes are evident during a lifetime of Earth's inhabitants.
Today, in our lifetime, we can see and witness the drying of many lakes across the Earth and their total disappearance from maps of only 50 years ago is a testimony to a climatic change taking place. The time of a 'complete' change in the Permian is possible to calculate. However, to determine the duration and maximum change in the climate of the earth today is impossible due to the apparent acceleration of the process by industrial activities of our species.
Chapter 4in the book deals with the special characteristics of the Permian coals of Gondwana and the special plant community which made them. The composition of these coals on a microscopic level shows them to be rich in hydrocarbons, more than other coals. The Permian coals of India and Australia generate 'heavy' oil which is retained within the coal matrix as bitumen and is a potential source of methane. This chapter demonstrates through a pilot study the potential for explosion in the Permian Gondwana coals through their propensity to spontaneous combustion and methane generation.
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