Data from: Amazonian pollen assemblages reflect biogeographic gradients and forest cover

Aim: We aim to assess i) how pollen assemblages vary across biogeographic and environmental gradients, ii) the source area of pollen assemblages from lake sediment samples, and iii) which pollen taxa can best be used to quantify deforested landscapes.

Location: Amazonia

Taxon: Plantae

Methods: Pollen assemblages (N = 65) from mud-water interface samples (representing modern conditions) of lake sediment cores were analysed and compared with modern gradients of temperature, precipitation, and elevation. Pollen assemblages were also compared with local scale estimates of forest cover at 1, 2, 5, 10, 20, and 40 km buffers around each lake.

Results: Over 250 pollen types were identified in the samples, and pollen assemblages were able to accurately differentiate biographic regions across the basin, corresponding with gradients in temperature and precipitation. Poaceae percentages had a significant negative relationship with forest cover estimates, which were stronger at the 1 km buffer and weaker as buffer sizes increased.

Main conclusions: The diverse Amazonian pollen assemblages strongly reflect environmental gradients, and percentages of Poaceae best reflect local scale variability in forest cover. Our results of modern pollen-landscape relationships can be used to provide a foundation for quantitative reconstructions of climate and deforestation in Amazonian landscapes.