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Non-pollen palynomorphs comprising algal remains, namely Botryococcus, Chara, Concentricystis, Pediastrum, Spirogyra and Zygnema as well as fungal spores such as ascospore types, Alternaria, Cookeina, Curvularia, Diplodia, Glomus, Helminthosporium, Nigrospora, Microthyriaceae and Tetraploa, well identified from the palynoslides prepared basically for the study of palaeovegetational succession and palaeoclimatic reconstructions, are discussed and illustrated from the late Quaternary sediments collected from southwestern Madhya Pradesh (India), which is regarded as one of the core monsoon zones of the Indian subcontinent. Botryococcus and zygospores of Zygnemataceae indicate warmer climate. PediastrumBotryococcus alternation may reflect colder -warmer climates. Botryococcus and Pediastrum may also suggest oscillations in atmospheric precipitation. They could be sensitive indicators of salinity, pH, temperature and depth changes in palaeolagoons influenced by sea-level oscillations and climate. Chara points to less oxygenated and hard water conditions. The record of fungal spores advocates the prevalence of a humid climate.

Pollen analysis and radiocarbon dating of a 1.4 m deep lacustrine sediment profile from Chhattisgarh State, central India, in the core monsoon zone (CMZ), has revealed the vegetation history, associated climate change and the Indian Summer Monsoon (ISM) rainfall variability during the Late-Holocene. The pollen evidence suggests that between ca. 3000 and 2600 cal year BP, tree-savannah vegetation occurred in the region having a comparatively lesser monsoon rainfall. The forest expanded and culminated into an open-mixed tropical deciduous forest between ca. 2600 and 2200 cal year BP under a warm and moderately humid climate with an increase in monsoon rainfall. Subsequently, between ca. 2200 and 2000 cal year BP, the existing open-mixed tropical deciduous forest transformed into a mixed tropical deciduous forest under a warm and humid climate with further increase in monsoon rainfall. Finally, between ca. 2000 and 1800 cal year BP, a dense mixed tropical deciduous forest occupied the landscape under a regime of a warm and relatively more humid climate with further strengthening of the ISM. The gradual warming, and the climatic amelioration with the intensification of the ISM, during the Late-Holocene (ca. 2600–1800 cal year BP; ~650 BC to AD150) corresponds to the Roman Warm Period (RWP), recorded globally between 2500 and1600 cal year BP (~550 BC to AD ~350). Human activities were present around the study area, which varied according to the ISM variations. The present study provides insights into the gradual intensification of the monsoon since the last ca. 2600 cal year BP (between ca. 2600 and1800 cal year BP), and an increase in the ISM strength in the CMZ of India, against the generally weakening trend during the Late-Holocene.

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