Climatic Change on the Iberian Peninsula Recorded in a 30,000-Yr Pollen Record from Lake Banyoles

Abstract

The Banyoles lacustrine sequence shows that the vegetational history of the northeastern Iberian Peninsula during the last 30,000 yr follows the North Atlantic pattern of climatic oscillations. The Banyoles pollen diagram, supported by two calibrated 14C dates and nine U/Th dates, shows a clear interstadial event between 30,000 and 27,000 yr B.P., a Pleniglacial period with minor oscillations that ended abruptly ca. 14,420 ± 410 yr B.P., and a late-glacial sequence that records the classical stages described in Northern Europe: the Bølling-Allerød Interstade, the Younger Dryas event at 12,000 yr B.P. (U-series age), and a short warming phase between the Younger Dryas and the last cold event (dated at 11,000 yr B.P., U-series age).

The sedimentary records in Mediterranean rockshelters and caves: Archives of environmental change

“…Long pollen records from lake basins in southern Europe have provided perhaps the most detailed records of Quaternary environmental change in the Mediterranean region (e.g., Wijmstra, 1969;Pons and Reille, 1988;Perez-Obiol and Julia, 1994;Tzedakis, 1993;Allen et al, 1999). Many of these records are well dated, and, because of more or less continuous sedimentation and favorable conditions for pollen preservation, these records can be correlated over extensive areas (Tzedakis et al, 1997).…”

Western Mediterranean climate and environment since Marine Isotope Stage 3: a 50,000-year record from Lake Banyoles, Spain

“…Oxygen and carbon isotope analysis of carbonate (δ 18 O calcite and δ 13 C calcite ) was performed at the same subsample intervals as those used in Höbig et al (2012), comprising 10 cm resolution from the base of the core to the base of the upper peat layer at 2.70 m. For the cross-core correlation, we compared the new isotope data with isotope and palynological data from the La Draga sequence (Pérez-Obiol and Julià 1994;Valero-Garcés et al 1998). …”

“…Thus, δ 13 C TDIC derived solely from C3 soil-CO 2 is predicted to have δ 13 C between -22 to -10‰, and C4 soil-CO 2 between -7 to +1‰. Catchment vegetation is known to have comprised varying percentages of both arboreal and non-arboreal taxa through time (Pérez-Obiol and Julià 1994). Therefore, the estimated values for δ 13 C TDIC are isotopically lower than both the Banyoles modern surface waters (δ 13 C DIC = -3.3‰, measured in 2011; B. Valero-Garcés, unpublished data) and BAN II core data (δ 13 C calcite range = -3.4‰ to +2.9‰), suggesting that organic-derived soil-CO 2 is potentially a component of δ 13 C TDIC , although in addition there must be an isotopically heavier δ 13 C source.…”

“…Previous work on Lake Banyoles employed palynological, sedimentological and geochemical techniques for palaeoclimate reconstruction and to improve understanding of the modern physical limnology. In an early palynological study of the lake sediment core, "La Draga" (named after an adjacent Early Neolithic site excavation), Pérez-Obiol and Julià (1994) showed climatic instability during the Glacial, followed by a rapid transition to the Bølling-Allerød interstadial and the Younger Dryas event, suggesting that the lake responds to North Atlantic climate forcing. Valero-Garcés et al (1998) Minimum precipitation occurs during summer and winter months (July, 37 mm; January, 43 mm), and maximum rainfall is during autumn and spring (October, 116 mm; March, 90 mm).…”

“…The lake is therefore characterised as a marl lake, which are typical of Mediterranean karst catchments (Leng and Marshall 2004;Roberts et al 2008). Average sediment accumulation rate was estimated to be about 1 mm yr -1 throughout the La Draga sequence (Pérez-Obiol and Julià 1994), although this value is subject to errors inherent in the previous age model.…”