“…The distribution pattern of vegetation is strongly dependent on the climatic conditions (precipitation, temperature), soil characteristic and altitude, as well as on human impact (Chen et al, 2006;Faegri & Iversen, 1964;Gasse et al, 1991;Ivanov et al, 2007;Kar et al, 2022;Kar & Quamar, 2019;Mishra et al, 2022;Quamar & Kar, 2020b;Sun & Wu, 1987 and references cited therein). Moreover, characterising pollen, which is produced by the vegetation itself, and its spatial distribution in a geological past regarding the existing vegetation structure of an area is crucial for understanding past climatic changes (Birks & Birks, 1980Gaillard et al, 1992;Gosling et al, 2005;Jackson & Williams, 2004;Kar & Quamar, 2019;Mohanty et al, 2024;Quamar, 2020;Quamar & Kar, 2020a;Quamar et al, 2023Quamar et al, , 2024Traverse, 1988 and references cited therein). Rational knowledge and understanding of modern pollen-vegetation relationship is, moreover, imperative and prerequisite for the reconstruction of past vegetation and climate change through studying the fossil pollen records (Bradshaw & Webb, 1985;Birks & Berglund, 2018;Faegri & Iversen, 1989;Jackson, 1994).…”