In the focus of this study are the sedimentary characteristics, chronology, magnitude, and causes of past soil erosion dynamics of an agriculturally intensively used glacial lowland landscape. From the mesoscale Quillow river catchment, sedimentary sections bearing colluvial sediments from different landforms were analysed to explore their geoarchive potential and to establish a local chronology of Late Holocene soil erosion. Sections from footslopes contain a rather simple stratigraphy with one topping colluvial horizon of up to 1 m thickness burying a palaeosol. In contrast glacial kettle holes preserve more complex sequences partly having several colluvial layers with intercalating palaeosols. The most complex stratigraphy is associated with a kettle hole being the ultimate sediment trap for a dendritic gully system, forming a 4 m thick sequence of alternating peat and colluvial layers. Thirty OSL ages and 13 radiocarbon ages are used to reconstruct phases of soil erosion. Potentially human-induced soil erosion, which is corroborated by local archaeological and palynological data, can be traced back to the last c. 4000 years. The oldest colluvial deposits date back to the Late Bronze Age. Most datings, however, cluster within the last 600 years with a peak in the last 200 years, ascribing the main phase of local soil erosion to the recent past. Thus, although numerous archaeological finds are detected in the catchment since the Neolithic, considerable agricultural soil erosion does not occur before the last millennium. A compilation of OSL chronologies based on colluvial sediments from other regions in Central Europe shows a more complex erosion history there with a pronounced two-or three-phased distribution of ages primarily dating into the last c. 4000-5000 years. This study underlines that in northeastern Central Europe human impact on landscapes was effective apparently at a later stage as compared to some adjacent regions.

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The Northeast German Lowland Observatory (TERENO-NE) was established to investigate the regional impact of climate and land use change. TERENO-NE focuses on the Northeast German lowlands, for which a high vulnerability has been determined due to increasing temperatures and decreasing amounts of precipitation projected for the coming decades. To facilitate in-depth evaluations of the effects of climate and land use changes and to separate the effects of natural and anthropogenic drivers in the region, six sites were chosen for comprehensive monitoring. In addition, at selected sites, geoarchives were used to substantially extend the instrumental records back in time. It is this combination of diverse disciplines working across different time scales that makes the observatory TERENO-NE a unique observation platform. We provide information about the general characteristics of the observatory and its six monitoring sites and present examples of interdisciplinary research activities at some of these sites. We also illustrate how monitoring improves process understanding, how remote sensing techniques are fine-tuned by the most comprehensive ground-truthing site DEMMIN, how soil erosion dynamics have evolved, how greenhouse gas monitoring of rewetted peatlands can reveal unexpected mechanisms, and how proxy data provides a long-term perspective of current ongoing changes.

An interdisciplinary study was carried out to trace the hydrological changes of the Havel River in northeastern central Europe over the last ca. 2000 years. This research was driven by the hypothesis that the present‐day riverscape is to a large degree a result of medieval and modern human transformation of the drainage system. The river system forms a series of dammed lakes and river sections that were greatly altered through hydraulic engineering in the past. Along the middle course of the Havel, 16 sedimentary sequences available for geoarchaeological and paleoecological research were analyzed in order to reconstruct regional water level dynamics. Chronological control was ensured through a multitude of palynological, dendrochronological, archaeological, and radiocarbon data. The sections upriver from the Brandenburg/H. and Spandau weirs, representing sites with historic watermills, reveal substantial water level changes during the late Holocene. Generally, lower water levels before and higher levels during the medieval German colonization of that area (ca. A.D. 1180/1250) can be inferred. This water level increase, which is primarily attributed to dams constructed for watermills and secondarily due to a multitude of fish weirs, took place rapidly and amounted to a relative height of ca. 1.5 m. It enlarged the river's cross‐sections and increased the size of existing lakes or initiated secondary lakes that previously aggraded, and thus caused flooding of large parts of land. The rising water level even influenced the settlement topography to a large degree. Several medieval rural settlements were abandoned due to flooding. In total, a ca. 150‐km long dammed lake cascade was formed.