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Sedimentary response of lake El Tobar, Spain, to climate: lake level changes after the Maunder Minimum

Abstract:

Lake level reconstructions from a littoral core in lake El Tobar, Spain, are presented for the last 350 years. These are based on plant macrofossils and stable isotopes from lacustrine carbonates. Our data suggest five episodes of advance and regression of the shoreline coupled with changes in water retention in the lake. A low lake level and high water renewal episode at ca. AD 1650–1715 is indicated by oxidized facies with abundant remains from terrestrial/marsh plant macrofossils and low δ18O and δ13C values. A fluctuating lake level episode at ca. AD 1715–1772 during changing climatic conditions in the Little Ice Age (LIA) caused periods of erosion and sediment deposition that intermittently blocked the lake outlet, resulting in more positive δ18O and δ13C values. The lake became progressively more closed with increased level in the wet years at the end of the LIA (ca. AD 1772–1850). During the Dalton Minimum, δ13C values reached a minimum, indicating low productivity, but increased after this with development of submerged Chara. From ca. AD 1850 to 1960 lake levels were high but are marked by changes in marsh communities, mainly the shift from Juncus to Typha (ca. AD 1850–1960) predominance, which indicates low and high levels, respectively.