Climate Change and Human History in Ganga Plain during Late Pleistocene-Holocene

Abstract

The Ganga Plain exhibits a large variety of landforms produced essentially during last about 100 kyrs in response to base level, tectonic and climate change. Prominent changes in the monsoon rainfall in the Ganga Plain have been identified, namely, 45 kyrs BP, humid climate; 20-13 kyrs BP, low rainfall; 13-11.5 kyrs BP, high rainfall; 11.5-10.5 kyrs BP, low rainfall; 10.5-5.8 kyrs BP, high rainfall; 5.8-2.0 kyrs BP, low rainfall; and 2.0-0 kyrs BP, high rainfall. Palaeo-vegetation studies indicate that the Ganga Plain was a grassland, at least, since 45 kyrs BP, where C-4 type vegetation dominated. The lakes supported C-3 type vegetation and they show changes in the water budget in response to the changes in rainfall. There is evidence of occupation of Ganga Plain by humans, at least, since 45 kyrs. They occupied the high grounds close to the water bodies, mostly lakes and ponds. Initially human population was hunter-gatherer depending on rich fauna and wild vegetation. Frequent climate changes in latest Pleistocene-Early Holocene probably led to adaptation of agricultural practices by humans. Large-scale occupation of the Ganga Plain took place between 3.5-3.0 kyrs BP. Study of oxygen isotopes in teeth enamel show century-scale rainfall changes in the last 3.5 kyrs BP which show some correlation to the cultural changes in the Ganga Plain. Climate change and human history in the Ganga Plain is closely related and need to be studied by high-resolution investigations.