Laguna Seca sediments reveal environmental and climate change during the latest Pleistocene and Holocene in Sierra Nevada, southern Iberian Peninsula Jiménez Moreno, Gonzalo López Avilés, Alejandro Jesús García-Alix Daroca, Antonio Camuera, Jon Mesa Fernández, José Manuel López Blanco, Charo Vegetation Lake level Climate Late Pleistocene Holocene Western Mediterranean This study was supported by the I + D + i projects CGL2013-47038- R, CGL2017-85415-R, PID2019-1049449GB-I00, and PID2021- 125619OB-C21/C22 funded by Ministerio Ciencia e Innovación/Agencia Estatal de Investigación/ 10.13039/501100011033/ and Fondo Europeo de Desarrollo Regional “Una manera de hacer Europa”, I + D + i projects A-RNM-336-UGR20 and P20_00059 of the action “Proyectos I + D + i del Programa Operativo FEDER - Junta de Andalucía - UGR” and the research group RNM-190. This research is part of the project “Thematic Center on Mountain Ecosystem & Remote sensing, Deep learning- AI e-Services University of Granada-Sierra Nevada” (LifeWatch-2019- 10-UGR-01), which has been co-funded by the Ministry of Science and Innovation through the FEDER funds from the Spanish Pluriregional Operational Program 2014-2020 (POPE), LifeWatch-ERIC action line. José Carrión was supported by the I + D + I project PID2019-1049449 GB-I00 funded by MCIN/AEI/ 10.13039/501100011033/ and FEDER “Una manera de hacer Europa” and the fellowship 20788/PI/18 of Fundación Séneca. We thank Javier Jaimez for his help with the core drilling in Laguna Seca and Alejandro Navarro and Aurora Baquera for the sediment sampling. ALA acknowledges the predoctoral fellowship BES- 2018-084293 provide by the MCIN/ AEI/ 10.13039/5011000110 33/. CLB acknowledges the European Union for her Marie Sklodowska-Curie grant agreement number 892487 under Horizon 2020 funds. JC acknowledges the Ministerio de Ciencia e Innovación of the Spanish Government for the grant number FJC2020-044215-I of the Juan de la Cierva Formación postdoctoral program. Sedimentation in most glacial lakes and wetlands in the Sierra Nevada (southern Iberian Peninsula) began after the last deglaciation and since the Younger Dryas (YD)-Early Holocene (EH) transition. Therefore, until now, studies on older sedimentary records were lacking in this alpine area, which limits the paleoenvironmental and paleoclimatic information to the Holocene. In this study, we studied palynomorphs from the alpine record from Laguna Seca (LS), the longest and oldest (∼18,000 cal yr BP = 18 kyr) sedimentary record in the Sierra Nevada to investigate the response of forests and lake environments in the western Mediterranean area to climate changes and human impact during the latest Pleistocene and Holocene. The deepest lake conditions occurred during the last deglaciation, indicated by the occurrence of Pediastrum algae, which showed highest abundances during the Heinrich Stadial 1 (HS1) and Bølling-Allerød (B-A) transition. Xerophyte herbs such as Artemisia, Ephedra, and Amaranthaceae were highest during the late B-A and YD indicating regional aridity. Poaceae (grasses) were maxima in the B-A and EH, probably indicating expansion in the barren areas after deglaciation. Maximum in temperature and humidity during the EH and cooling and aridification in the Middle (MH) and Late Holocene (LH) are indicated by the changes in the abundance of deciduous Quercus and Pinus forest species. Botryococcus algae increased during the Early Holocene, while the rest of the algae almost vanished, which could indicate that the lake became very productive but shallower until 8.2 kyr. The lake level lowered and became seasonal in the Middle-Late Holocene transition, coinciding with the regional climate aridification. Microcharcoal analysis done on the palynological preparations agrees with the vegetation changes, showing maxima in the EH and MH, related with the maximum in regional forest occurrence, and a decrease in the LH when the Mediterranean vegetation, and thus fuel availability, diminished. This record shows evidence of anthropogenic impact in the last centuries by cultivation, reforestation, cattle grazing, enhanced erosion and eutrophication. 2023-12-07T10:45:32Z 2023-12-07T10:45:32Z 2023-10-05 info:eu-repo/semantics/article G. Jiménez-Moreno et al. Laguna Seca sediments reveal environmental and climate change during the latest Pleistocene and Holocene in Sierra Nevada, southern Iberian Peninsula. Palaeogeography, Palaeoclimatology, Palaeoecology 631 (2023) 111834 [https://doi.org/10.1016/j.palaeo.2023.111834] https://hdl.handle.net/10481/86063 10.1016/j.palaeo.2023.111834 eng info:eu-repo/grantAgreement/EC/H2020/MSC 892487 http://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess Atribución 4.0 Internacional Elsevier