This dataset presents the relative abundance of pollen and spores from 68 sediment samples collected at 0.10 m intervals along core NGR07, retrieved from Lake Pacú in the lower Negro River region, Central Amazonia. The analyses were conducted to reconstruct past vegetation dynamics in response to mid- to late Holocene hydrological variability. Palynomorphs were identified using regional pollen reference collections and published identification keys. Approximately 300 grains were counted per sample (except in pollen-poor intervals), and Lycopodium spores were added as exotic markers to calculate concentration values. The dataset provides insights into shifts in floodplain forest composition, herbaceous vegetation patterns, and the evolution of modern igapó systems over time. Pollen diagrams and cluster analyses were produced using Tilia and CONISS software.

Further method/device information:Instrument Type: Optical microscope, Zeiss, Axiolab 5 with Axiocam 208 color camera (430037-9110-000, Microscopy GmbH).Preparation Method: Modified acetolysis method according to Stockmarr (1971).The steps include: Pre-treatment with 10% HCl to remove carbonates; Treatment with 40% HF to remove silica and other minerals; Acetolysis using a 9:1 (v/v) mixture of acetic anhydride and sulfuric acid to dissolve organic matter; Washing with distilled water until neutral pH;* Mounting on slides with glycerin for microscopic analysis.Counting and Analysis: Approximately 300 grains of pollen and spores (combined) were counted per sample using a Zeiss Axiolab 5 optical microscope equipped with an Axiocam 208 color camera at a magnification of 1300×.Identification References: Roubik & Moreno (1991; doi:10.2307/4110734); Colinvaux et al. (1999, doi:10.1201/9781482283600), Leal et al. (2011; doi:10.1080/01916122.2011.603909) and Yao & Liu (2018; doi:10.3389/fevo.2017.00178).