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Long-term experiments are essential in understanding the ecological consequences of global land use and climate change. Further, it is well established that longterm data sets are prerequisites for effective management of forest resources and biodiversity conservation. In view of this, the present study attempts to contribute to major global long-term ecological monitoring (LTEM) networks and the status of LTEM studies in India with a special focus on Indian Himalayan Region. Over the last 40 years, around 103 countries from the America, Europe, Africa, Asia and Australia have been engaged in LTEM studies on various aspects of biodiversity, monitoring and predicting climate change impacts in a range of ecosystems, including the mountains. The temporal distribution of past studies on the subject shows a gradual increasing pattern (3 papers in 1992) with a peak during 2021 (105 papers). The established LTEM networks across the globe provide a significant empirical basis for understanding ecosystem structure and dynamics. Literature indicates plenty of permanent monitoring plots from India, mostly from southern India, and their significant contribution to ecosystem understanding. Himalayan regions are important sites for monitoring biological and socio-ecological responses to environmental perturbations, including climate change. LTEM studies are lacking in the IHR; only a few sites have been established, mostly in alpine ecosystems. This review identifies research gaps, opportunities with respect to LTEM studies, and the possibilities for strengthening long-term research and observation in India in general and the Himalaya in particular. [ABSTRACT FROM AUTHOR]

A palynological assay of the studies carried out from the Western and the Eastern Himalaya (India) during the Late Pleistocene and Holocene is presented here. The Western Himalaya is affected by both the Indian Summer Monsoon (ISM) and Western Disturbances, whereas the Eastern Himalaya receives precipitation only from the ISM. During the Late Pleistocene (~77 ka), a cold and arid climate supported steppe vegetation in the Western Himalaya. In the Eastern Himalaya, around 66 ka, a cool and dry climate supported the savannah vegetation with few scattered trees of Pinus and Tsuga. A number of warm-moist fluctuations are also perceptible during the Late Pleistocene. The impacts of Last Glacial Maximum, Holocene Climatic Optimum, Medieval Warm Period and Little Ice Age are well discernible in the vegetation in both the regions. Within a broad similarity, the climate change and associated vegetation succession varied from region to region; as the palynological records are characterized by the evidences of prolonged humid phases in the eastern sector, whereas the arid events are better marked in the western part. The similarities and incompatibilities in the climate and vegetation between the Western and Eastern Himalaya during the Late Pleistocene and Holocene are discussed in the present paper. [ABSTRACT FROM AUTHOR]

The Siwalik foreland deposit was earlier considered as freshwater continental megafan deposit, formed by southward flowing transverse drainages, analogous to modern Kosi-like megafans. However, this analogy remained incomplete due to lack of evidence of a regionally persistent axial stream system or marginal marine depositional system, like the Ganga-Brahmaputra River and Ganga Delta, as in the present-day foreland basin. In this paper, we report the abundant wave-generated structures and marine trace fossils from the Siwalik succession of the Tista valley and infer that they represent the deltaic part of the Neogene foreland basin. This interpretation provides the link between upland fluvial deposits of the western Himalaya and deep marine sediments of the Bengal Fan and is more consistent with available data from the Siwaliks of the eastern Himalaya. It also implies that a marine embayment existed in the eastern part of the Siwalik foreland basin. [ABSTRACT FROM AUTHOR]