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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.

Understanding the spatiotemporal monsoonal variability during the Holocene helps in understanding the rise and fall of many civilizations. In this study, a 2.65 m high palaeo lake sedimentary profile from the Kumaun Lesser Himalaya, Uttarakhand State, India was pollen analysed to reconstruct the variability in the monsoonal precipitation during the Middle Holocene. The study revealed that between ~7522 and 7216 cal yr BP, conifers dominated mixed broad-leaved forests occurred around the landscape of the study area, indicating a less cold and dry climate with decreased monsoon precipitation. Broad-leaved taxa during this phase show increased values considerably, indicating amelioration in climatic condition, which could be, in global perspective, broadly falling within the time-interval of the Holocene Climate Optimum (HCO; 7000–4000 BP). Between ~7216 and 6526 cal yr BP, dense conifers-dominated mixed broad-leaved forests transformed the conifers-dominated broad-leaved forests around the study area under a cold and drier climate with further reduction in monsoon precipitation. Subsequently, between ~6526 and 5987 cal yr BP, conifers-dominated broad-leaved forests continued to grow, but with lesser frequencies, around the study area under a comparatively less cold and dry climate with reduced monsoon precipitation. Finally, between ~5987 and 5817 cal yr BP, the frequencies of conifers-dominated broad-leaved forests further decreased around the landscape of the study area under a comparatively lesser cold and dry climate, probably indicating decreased monsoonal precipitation. Hence, the present study mainly showed the dominance of conifers forests around the study area between ~7522 and 7216 cal yr BP, ~7216 and 6526 cal yr BP, ~6526 and 5987 cal yr BP and between ~5987 and 5817 cal yr BP; however, broad-leaved forests also demonstrated increasing tendency between ~7522 and 7216 cal yr BP in the milieu of cold and dry climates. Moreover, the study also revealed that a lake was formed around 7522 cal yr BP along the Kulur River, a tributary of Saryu River around the study area and existed until 5817 cal yr BP.

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Pollen assemblages provide valuable insights into the beginning of cereal-based agricultural practices and the transition from a hunting and gathering to a sedentary and food-producing way of life. Anthropogenic pollen indicators (APIs) and their precise identification, with respect to taxonomic resolution, can help to document the history of agricultural development, pastoral activities and human-induced land-use changes, particularly for the Holocene Epoch. Moreover, careful selection of pollen types, and/or indices, established for a particular region, are useful for obtaining meaningful reconstructions of anthropogenic activities through time. Specific pollen-markers have been used to deduce the inception of agriculture and the impact of anthropogenic activities on the landscape, from the different regions of the world. For India, Cerealia, and other cultural plant pollen taxa, such as Amaranthaceae, Caryophyllaceae, Brassicaceae, Polygonaceae, Artemisia, Cannabis sativa, Alternanthera, Urtica, Rumex and Borreria have been used as marker pollen types for indicating agricultural practices and other anthropogenic activities. In this communication, we have made an attempt to trace the advent and intensification of agricultural practices in the varied physiographic regions of the Indian sub-continent, on the basis of the available palynological records. We have further critically analysed the plausibility of agricultural practices and other human activities during the Late Pleistocene/Pre and Early Holocene with respect to the Indian scenario.

Angiosperms demonstrate a surprisingly frequent phenomenon of variability in the gross pollen morphological characteristics. In thepresent study, we recorded and described a new aperture in the pollen grains of Schleichera oleosa (Lour.) Oken, a monotypic genusof the soapberry family Sapindaceae, from Madhya Pradesh, central India, based on the LM and CLSM observations. This condition istermed the tetra-zono-parasyncolporoidate condition. A new pollen aperture has been recorded in this monotypic genus with theusual one (tri-zono-parasyncolporoidate condition), and this phenomenon of the occurrence of a new with increased number of pollenaperture is known as pollen aperture heteromorphism. The study will further help identify this taxon from the sedimentary archives asone of the indicators of the warm and humid (moist) climate and increased monsoonal rainfall.