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One of the current activities of the INTIMATE Network is the organization of bi-annual research training schools for Early Career Scientists. During these INTIMATE Example summer schools, fieldwork, lectures and lab-based activities are executed focusing on a central theme or specific site. The fourth INTIMATE Example Research Training school centered around the coring of Lac Retournemer in July 2018, and aimed at collecting a Lateglacial-Holocene record of past environmental change. Retournemer is located in the High Vosges mountains, and is a nice example of a cirque lake that was formed during the Weichselian. Lac Retournemer is located at 776m above sea level in the head-waters of the Vologne Valley and is currently a 11m deep lake behind a glacial threshold consisting of igneous rock. This area is one of the wettest areas in France with high precipitation values and might therefore be a good site to record Icelandic tephras. Previous investigations show that at least 15m of partially laminated sediments are present in this basin with also a possible occurrence of Laacher See Tephra. During the summer school we obtained a 18m sediment record before we reached the basal glaciolacustrine sediments at 29 m below water level. In the top part of the sequence, clear sediment fluxes can be observed which might be linked to human impact or increased precipitation events in the catchment. The first results from the basal part of the sequence show a clear Lateglacial and Early Holocene record with Laacher See Tephra in a laminated sequence and a possible occurrence of Vedde Ash in the more siliciclastic Younger Dryas sediments. The Loss on Ignition profile shows multiple fluctuations in the Lateglacial Interstadial and Early Holocene which might be linked to the oscillations in the INTIMATE event stratigraphy for this time period. Preliminary palynological results support the Lateglacial and Early Holocene age of the sequence and will be further explored to investigate the differences in response with other proxies such as chironomids, geochemistry etc. The occurrence of Laacher See and Icelandic tephras in the core will add to the existing tephra lattice for the Lateglacial and Early Holocene in Central and NW Europe. [ABSTRACT FROM AUTHOR]

On the basis of seven palynological records, we reconstruct the forest-limit composition and dynamics during the second part of the Holocene, in the upper montane and subalpine zones of the Monts du Forez in the north-eastern Massif Central, using a 2 km long, elevational transect of sites at 1335–1590 m elevation. All sites are mires today, varying in size from 2 to <0.1 ha. The chronology of the pollen diagrams is based on calibrated radiocarbon dating combined with pollen-stratigraphic correlation among the diagrams using the regional pollen component. Corylus avellana forest with Ulmus developed in the study region soon after the start of the Holocene. Soon after Fagus sylvatica arrived in the study area and expanded after ca. 3500 BC (5450 cal yr BP) to full abundance within a few centuries at the cost of Corylus. Abies alba expanded slowly within the Fagus forest after ca. 3300 BC (5250 cal yr BP), taking two millennia to reach its final abundance. During ca. 800–650 BC (2750–2600 cal yr BP) Fagus and Abies had reached similar overall abundances and formed forests only minimally affected by prehistoric human impact, which could serve as a natural baseline condition for extant forest management. We hypothesise that during this period dense Abies – Fagus krummholz had an upper limit of 1570 m, with scattered Abies trees above this and open woodland of Sorbus , Betula and Acer up to the summit (1634 m a.s.l.). A varied cultural landscape was in place in medieval times, with cereal cultivation and grasslands in a predominantly forested landscape. A baseline condition of this kind of cultural landscape could be found in late medieval times. During the last several centuries major deforestations took place and planted Pinus sylvestris replaced much of the originally natural Abies – Fagus forest. Crop cultivation increased in the cultural landscape. All diagrams have hiatuses (missing peat layers), which in most cases could be attributed to domesticated animals damaging the mire surface. For mire protection we therefore recommend a limited grazing pressure by cattle. The major phases in settlement history from the Neolithic to medieval times can be recognized in the pollen diagrams. [ABSTRACT FROM AUTHOR]