This paper reports the vegetation changes of the last millennium, as deduced from palynological analysis of a sediment core from lake Montcortès, situated around 1000 m elevation in the southern pre-Pyrenean flank. The record begins in the Middle Ages (~AD 800) and ends around AD1920, with an average resolution of about 30 years. The reconstructed vegetation sequence is complex and shows the influence of both climate and human activities in the shaping of landscape. Prefeudal times were characterized by the presence of well-developed conifer forests, which were intensely burnt at the beginning of the feudalism (AD 1000) and were replaced by cereal (rye) and hemp cultivation, as well as meadows and pastures. In the 13th century, a relatively short warming likely corresponding to the Medieval Warm Period (MWP) was inferred by the presence of a low Mediterranean scrub community today restricted below 800 m elevation. This community disappeared during the Little Ice Age (LIA) cooling in the 15th century, coinciding with a decline in human activities around the lake. Forest recovery began around AD 1500, at the beginning of the Modern period, coinciding with wetter climates. However, forests retreated again during the 17th century coinciding with a maximum in olive and hemp cultivation. This situation was reverted in post-Modern times (19th century), charactrized by an intense agricultural crisis and a significant decline of population that favored forest re-expansion. Correlations with the nearby Estanya lake, situated about 350 m below, provided a more regional picture. Besides some climatic forcing evident in both sequences, human activities seem to have the main drivers of landscape and vegetation change in the southern Pyrenean flank, in agreement with similar conclusions from other studies developed on high-mountain environments.

Easter Island (SE Pacific, 27ºS) provides a unique opportunity to reconstruct past climate changes in the South Pacific region based on terrestrial archives. Climates in the mid-to lowlatitude region of the eastern South Pacific Ocean are controlled by fluctuations in the Westerlies winds, the South Pacific Convergence Zone and the South Pacific Anticyclone. Here we present a high-resolution reconstruction of lake dynamics, watershed processes and paleohydrology for the last 34000 years based on a sedimentological and geochemical multiproxy study of 8 cores from the Raraku Lake sediments constrained by 22 AMS radiocarbon dates. This multicore strategy has reconstructed the sedimentary architecture of the lake infilling and provided a stratigraphic framework to integrate and correlate previous core and vegetation studies conducted in the lake.High lake levels and clastic input dominated sedimentation in Raraku Lake between 34 to 28 cal kyr BP. Sedimentological and geochemical evidences support previously reported pollen datashowing a relatively open forest in the watershed during the Glacial period and a cold and relatively humid climate. Between 28 and 17.3 cal kyr BP, including the LGM period, colder conditions contributed to a reduction of the tree coverage in the island. The end of Glacial Period occurred at 17.3 cal kyr BP and was characterized by a sharp decrease in lake level conducive to the The main aim of the manuscript that we are submitting to Quaternary Science Reviews is to provide new insights about the environmental and climate evolution of Easter Island during the last 34000 cal years BP. We have achieved this aim through the high resolution study of new eight cores recovered in March 2006 at Lake Raraku and constrained by 22 AMS radiocarbon dates. This is the first time that a multicore strategy coupled with sedimentological, mineralogical and geochemical techniques are applied to Raraku Lake. As a result, we have been able to reconstruct the architecture of the lake sedimentary infilling and the limnological evolution of the lake. The reconstructed changes in terrigenous input, lake productivity, and lake level changes from Last Glacial to the present have been integrated with previous studies and the available pollen records to provide a paleoclimate reconstruction of the mid-to low-latitude southeastern Pacific region. The timing and characteristics of the main temperature and moisture changes in Easter Island show similarities with other terrestrial and marine records located in the south circum Pacific region. Moreover, our research provides new data on the impact in the lake ecosystem of human activities (deforestation and intensive cattle farming) during the last centuries.We suggest following reviewers because they are the main specialists in the topic of the manuscript: Mark

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Sedimentological, mineralogical and compositional analyses performed on short gravity and long Kullenberg cores from meromictic Montcortès Lake (Pre-Pyrenean Range, NE Spain) reveal large depositional and paleohydrological changes during the last 6000 cal. years BP. The limnological characteristics of this karstic lake, including its meromictic nature, relatively high surface/depth ratio (Surface about 0.1 km 2 ; Zmax=30 m), and steep margins, have facilitated the deposition and preservation of finely laminated facies, punctuated by clastic layers corresponding to turbidite events. Relatively shallower lake conditions prevailed during the Mid Holocene (6000-3500 cal. years BP), and deeper environments with deposition of varves with calcite laminae preservation occurred afterwards. Increased carbonate productivity and lower clastic input occurred during the Iberian-Roman Humid Period, the Little Ice Age and the 20 th century. Two episodes of higher clastic input to the lake developed: i) during the period 690-1460 AD, coinciding with an increase in the farming activity in the area and the Medieval Climate Anomaly; and ii) between 1770 and 1950 AD, coinciding with the last phases of the Little Ice Age and the maximum human occupation of the mountain areas in the Pyrenees. Slope instability has caused large gravitational deposits during the Mid Holocene (prior to 6 ka) and Late Holocene (prior to 1600 and 1010 cal. yr BP).