During the past millennia, many erosion and accumulation processes have been modified by anthropogenic impact. This holds especially true for the environs of ancient settlements and their harbours along the Mediterranean coasts. Our multi-proxy investigations in the Roman harbour and the harbour canal of Ephesus (western Turkey) reveals that humans have significantly triggered soil erosion during the last three millennia. Since the eighth century BC, and especially since the Hellenistic period, a high sedimentation rate indicates fast alluviation and delta progradation of the Küçük Menderes. Deforestation, agriculture (especially ploughing) and grazing (especially goats) were the main reasons for erosion of the river catchment area. One consequence was significant siltation of the Hellenistic/Roman harbour basin. This sediment trap archives the human impact, which was strongly enhanced from Hellenistic/Roman to Byzantine times (second/first centuries BC to the sixth/seventh centuries AD), evidenced by high sedimentation rates, raised values of heavy metal contaminations [lead (Pb), copper (Cu)], the occurrence of fruit tree pollen and of intestinal parasites. From the middle to the end of the first millennium AD, the influence of Ephesus declined, which resulted in a decrease of human impact. Studies of several ancient settlements around the Mediterranean Sea tell a comparable story. They also confirm that during their most flourishing periods the human impact totally overprinted the climatic one. To detect the latter, geo-bioarchives of relatively pristine areas have to be investigated in detail.

The Kolkheti lowlands (Colchis, Colchian plain) form the central part of the extensive coastal lowlands along the Black Sea coast of Georgia. Situated between the Greater and the Lesser Caucasus, favourable climatic conditions resulted in a constant human occupation of the region during the Holocene. However, due to continued deltaic sedimentation and alluviation of the river Rioni, the configuration and the environmental conditions of the coast and its hinterland have changed considerably; this was related to sea-level fluctuations of the Black Sea and variation of the sediment supply. This study presents new data on the Holocene coastal evolution of Western Georgia. Based on the geochemical and sedimentological analysis of sediment cores and trenches from the northern part of the Kolkheti lowlands, between the Black Sea and the rivers Rioni and Khobistsqali, and a robust chronology (14 C and IRSL dating), our goals are (i) to document the chronostratigraphy along two coring transects; (ii) to decipher geographical and environmental changes along Georgia's Black Sea coast; and (iii) to trace the sea-level evolution of the study area. Based on the succession of eight facies, representing different depositional environments, our results suggest that significant environmental changes took place throughout the last eight millennia. At least since 5000 cal BC, the sedimentary record indicates the widespread existence of shallow lagoons. Floodplain-related finegrained alluvium accumulated on top of the lagoonal stratum. The progradation of the delta plain between 3500 and 1500 cal BC was accompanied by the evolution of extensive swamps with peat formation. The data indicate a gradual and moderate sea-level rise since ~6000 BC. Ultimately, this and follow-up studies may provide a valuable background for the understanding of the palaeogeographical context of ancient settlements in the area.

Occurrence and distribution of microplastics in different ecosystems have recently become subjects of numerous studies. However, to date the research has focused mainly on marine and freshwater ecosystems and widely neglected terrestrial environments. Only recently, first studies investigated the microplastics contamination of soils. Therefore, we know little about the transport mechanisms of microplastics in soils and sediments and virtually nothing about their surface transport. In this study we investigate surface transport mechanisms by tracking fluorescent, irregularly shaped polymethyl methacrylate (PMMA) particles in real time in a laboratory setup. In 108 experimental runs, we vary the irrigation rates, inclinations and surface roughnesses. Additionally, we simulate the small-scale flow patterns to resolve the role of the roughness-induced microrelief. Our results suggest that microplastics are transported along preferential pathways resulting from the micro- and macrorelief, which can be correlated to the flow pattern observed in the computer simulation. Our model study facilitates a deeper insight into microplastic transport on different soil surfaces and serves as a pilot for investigating mechanisms of horizontal microplastic transport. However, microplastics are a diverse group of contaminants with varying shapes, densities and sizes. Therefore, for a full understanding of transport of microplastics in terrestrial environments, it is important to address these properties as well as more variable surfaces for horizontal migration and to include vertical transport mechanisms in future research.

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Situated between the Enguri and Khobistskali rivers, more than 30 settlement mounds (locally named Dikhagudzuba) provide evidence for a relatively densely populated landscape in the coastal lowlands of western Georgia during the Bronze Age. Compared to older mounds in eastern Georgia and other regions, these mounds differ not only in age but also in their average size and spatial distribution. Based on the interpretation of nine sediment cores, drone survey and structure‐from‐motion photogrammetry techniques, our study aims at (i) establishing a chronostratigraphic framework for the mounds based on 14C dating; (ii) reconstructing possible phases and gaps in human occupation; (iii) determining potential source areas of the mounds’ construction material; and (iv) identifying the environmental conditions at the time of their use. The three investigated mounds are similar in dimension and stratigraphy. Anthropogenic layers could clearly be identified and separated from the natural alluvial deposits below. According to the 14C age estimates, the mounds date to the first half of the 2nd millennium B.C.; this confirms the archaeological interpretation of their Bronze Age origin. While only one construction phase is assumed for two of the mounds, stratigraphic analysis suggests a successive enlargement of a third mound over at least 470 years. Paleoenvironmental conditions in the vicinity of the mounds were dominated by swampy, fluvial (channel) to alluvial (overbank) processes, as attested by river‐bank deposits and floodplain alluvium.