Modern pollen dispersal studies in India: a detailed synthesis and review

Abstract

Modern pollen dispersal studies from the phytogeographically and climatically different regions [the Peninsular and extra-Peninsular regions (the Himalaya), the Ganga-Brahmaputra Plain and the coastal regions] of India are summarised and reviewed in the present communication. We have incorporated all the works undertaken on modern pollen dispersal aspects in India. It must be noted that initial studies, though incipient in nature and content, helped in establishing the science of palynology, in the early days, across the varied regions of the vast country. Shorea robusta and Tectona grandis, despite being high pollen producers and dominant components of the deciduous forests, are under-represented in the pollen assemblages; however, Madhuca indica has comparatively good representation. Rhizophora, Aegiceras, Barringtonia, Excoecaria, Sonneratia and Avicennia are the important mangrove taxa recorded from the coastal areas, although their representation is less as compared to the extant vegetation. Mesua, Schima, Elaeocarpus, Ilex and Garcinia are represented well in the pollen spectra from the evergreen forests. Pinus pollen is highly over-represented in the Himalaya. Suggestions for overcoming limitations are also provided, which will improve the accuracy and understanding of modern pollen dispersal studies in the Indian scenario. Recommendations for future research mainly comprise adoption of the established protocols for vegetation surveys. Extended R-value (ERV) models may be applied for estimating the pollen productivity (PPEs) for further use in landscape reconstruction algorithm (LRA) approaches.