Pollen and charcoal from Tolhuaca National Park, south-central Chile

Aim: Few paleoenvironmental studies have been performed in Araucaria-Nothofagus forests, which are highly vulnerable to ongoing threats from climate change and anthropogenic activities. The primary goal of this work is to reconstruct past environmental changes related to fire disturbances over the last 1800 years in Tolhuaca National Park, Chile.
Location: Tolhuaca National Park, Araucanian region (38.2°S; 71.8°W), Northwestern Patagonia, Chile.
Taxa: Araucaria araucana (Araucariaceae), Nothofagus spp. (Nothofagaceae).
Methods: We completed charcoal and pollen analyses to create two new paleoecological records that span 1800 years. We compared the lake-based reconstruction with the available local tree-ring fire scar chronologies from the last 430 years. Using these data, we compute forest index changes, biomass burning trends, and compare with estimates of archaeological radiocarbon density. We place our inferences with context of published regional paleoclimatic proxies from the Patag..., Chronology: Two sediment cores were collected in Verde (112 cm) and Malleco (120 cm) lakes using an UWITEC gravity corer. Radionuclide measurements using a gamma spectrometer were performed to estimate the 210Pb, 226Ra (to support 210Pb activity), and 137Cs activities on the first 20 cm). In addition, AMS radiocarbon dating was performed in both lakes. Radiocarbon ages were calibrated using the SHCal20 curve (Hogg et al., 2020). The age-depth models were computed using an integrated chronology based on 210Pb, 137Cs, and 14C dates through Bayesian analyses in “rPlum” package (Aquino-López et al., 2018; Blaauw et al., 2020) in R platform.
Charcoal analyses: To infer fire regime, macroscopic (>125 µm) charcoal fractions were analyzed in Verde and Malleco cores. 2 cm3 of sediment were taken at 1 cm intervals for the length of the core, sieved through 125 μm and 250 μm screens, following the methodology outlined by Whitlock and Larsen (2001). 
Pollen analyses: Verde and Malleco cores were..., , # Pollen and charcoal from Tolhuaca National Park, south-central Chile
### Research article:

## Fire-climate-human dynamics over the last 1800 years in the mesic *Araucaria-Nothofagus* forests.

**Authors:** Martel-Cea, Alejandra (1,2,3), Abarzúa, Ana M. (2,4), González, Mauro E. (5,6,7), Jarpa, Leonora (2), Hernández, Marjorie (2).

**Journal:** Journal of Biogeography

**Year:** 2024

**DOI:** 10.1111/jbi.14839

**Corresponding author:** [[e-mail]](mailto:[e-mail])

**Affiliations:**

(1) Corporación Centro de Estudios Avanzados en Zonas Áridas, La Serena, Chile

(2) Instituto Ciencias de la Tierra, Ciencias, Universidad Austral de Chile. Valdivia, Chile

(3) Laboratorio Natural Andes del Sur, Universidad Austral de Chile. Valdivia, Chile

(4) Núcleo de Estudios Transdisciplinarios del Cuaternario del Sur de Chile (TAQUACh), Universidad Austral de Chile. Valdivia, Chile

(5) Instituto de Conservación Biodiversidad y Territorio, Facultad de Ciencias Forestales y Re...