Last millennium environmental changes and climate inferences in the Southeastern Atlantic forest, Brazil

Abstract

This study presents paleoenvironmental data based on pollen, elemental and isotopic compositions of organic matter (TOC,N,δ13C and δ15N) and 14C dating of 170 cm lake sediment record. Samplings have been made in Lagoa Grande at Parque Estadual Turítico do Alto Ribeira - PETAR, Southern São Paulo State, Southeastern Brazil. The variations in relative frequencies (in percentage) of arboreal pollen along the core range between 40 and 80%. The δ13C values ranged from -23‰ to -30‰ and C/N of ~10 to 15, indicating the contribution of terrestrial C3 plants and algae in the sediment organic matter. The δ15N results presented values from 3 to 4.5‰, also suggesting a mixture of algae and terrestrial C3 plants. The 14C dating indicates modern age for the shallow horizons to ~1030 BP at the base of the core. A probable wetter climate in the period of ~370 BP to ~340 BP was inferred from the data set, which corresponds to a part of the period covered by the Little Ice Age (LIA).