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In the transformation from tidal systems to freshwater coastal landscapes, plants act as eco-engineering species that reduce hydrodynamics and trap sediment, but nature and timing of the mechanisms of land creation along estuaries remains unclear. This article focuses on the Old Rhine estuary (The Netherlands) to show the importance of vegetation in coastal landscape evolution, predominantly regarding tidal basin filling and overbank morphology. This estuary hosted the main outflow channel of the river Rhine between ca 6500 to 2000 cal bp, and was constrained by peat during most of its existence. This study reconstructs its geological evolution, by correlating newly integrated geological data and new field records to varying conditions. Numerical modelling was performed to test the inferred mechanisms. It was found that floodbasin vegetation and resulting organic accumulation strongly accelerated back-barrier infill, by minimizing tidal influence. After tidal and wave transport had already sufficiently filled the back-barrier basin, reed rapidly expanded from its edges under brackish conditions, as shown by diatom analysis and datings. Reed growth provided a positive infilling feedback by reducing tidal flow and tidal prism, accelerating basin infilling. New radiocarbon dates show that large-scale crevassing along the Old Rhine River – driven by tidal backwater effect – only started as nutrient-rich river water transformed the floodbasin into an Alder carr in a next phase of estuary evolution. Such less dense vegetation promotes crevassing as sediments are more easily transported into the floodbasin. As river discharge increased and estuary mouth infilling progressed, crevasse activity diminished around 3800 to 3000 cal bp, likely due to a reduced tidal backwater effect. The insights from this data-rich Holocene study showcase the dominant role that vegetation may have in the long-term evolution of coastal wetlands. It provides clues for effective use of vegetati

Environmental changes have had an enormous impact on prehistoric hunter-gatherers as they affect the biotic landscape and availability of resources such as freshwater, edible plants, game and fish. To assess whether various innovations that took place in hunter-gatherer communities during the Boreal may be attributed to changes in the vegetation, a high-resolution pollen and macrofossil analysis of a well-AMS-dated Early Holocene peat record from the Grote Nete valley in the Belgian Campine was carried out. Shifts in the pollen assemblages indicate a change from a birch-pine woodland in the late Preboreal to pine-dominated forests in the Boreal. After the initial expansion of hazel, followed by oak and elm from the early Boreal onward, a prominent and abrupt reduction of the pollen concentration, by up to 95% over several spectra, is observed during the second half of the Boreal. This sharp decline affects all taxa and coincides with a decrease in pollen percentages of thermophilous trees and an increase of the cold-tolerant pine. This shift in pollen concentration and vegetation composition likely reflects a climatic cooling at 9.3 ka which is evident in the stable oxygen isotopic record of the Greenland ice cores. On the one hand, the vegetation dynamics are discussed in the light of the Boreal vegetation history in general and this temporary cooling more specifically. On the other hand, we discuss how these changes may have affected past hunter-gatherer communities.

Holocene drift-sand activity in the northwest European sand belt is commonly directly linked to population pressure (agricultural activity) or to climate change (e.g. storminess). In the Pleistocene sand areas of the Netherlands, small-scale Holocene drift-sand activity began in the Mesolithic, whereas large-scale sand drifting started during the Middle Ages. This last phase not only coincides with the intensification of farming and demographic pressure but also is commonly associated with a colder climate and enhanced storminess. This raises the question to what extent drift-sand activity can be attributed to either human activities or natural forcing factors. In this study, we compare the spatial and temporal patterns of drift-sand occurrence for the four characteristic Pleistocene sand regions in the Netherlands for the period between 1000 BC and AD 1700. To this end, we compiled a new supra-regional overview of drift-sand activity based on age estimates (14C, optically stimulated luminescence (OSL), archaeological and historical ages). The occurrence of sand drifting was then compared in time and space with historical-route networks, relative vegetation openness and climate. Results indicate a constant but low drift-sand activity between 1000 BC and AD 1000, interrupted by a remarkable decrease in activity around the BC/AD transition. It is evident that human pressure on the landscape was most influential on initiating sand drifting: this is supported by more frequent occurrences close to routes and the uninterrupted increase of drift-sand activity from AD 900 onwards, a period of high population density and large-scale deforestation. Once triggered by human activities, this drift-sand development was probably further intensified several centuries later during the cold and stormier ‘Little Ice Age’ (LIA; AD 1570–1850).

This dataset contains a new national overview of the occurrence of drift sand activity in the Netherlands from ca. 5000 BC to AD 1700. The dataset has been compiled from overview studies, field studies and new data., Deze dataset bevat een nieuw landelijk overzicht van stuifzandvoorkomen en activiteit voor de periode ca. 5000 voor Chr tot ca. 1700 na Chr in Nederland. De dataset is gebaseerd op diverse overzichtsstudies, losse veldstudies en nieuwe gegevens. Omdat de mens een belangrijke rol speelde bij het ontstaan van stuifzanden in deze periode in Nederland, is dit nieuwe overzicht nuttig om het samenspel tussen mens en landschap in het verleden beter te begrijpen. De dataset bevat up-to-date informatie waaruit afgeleid kan worden wanneer en waar de mens het stuifzand zou hebben kunnen veroorzaakt en wanneer het stuifzand mogelijk een bedreiging vormde voor de landbouw of nederzettingen. Daarnaast kan deze dataset fungeren als historische context bij huidige stuifzanden die als waardevolle natuurgebieden worden beschouwd.

A remarkably long period of Northern Hemispheric cooling in the 6th century CE, which disrupted human societies across large parts of the globe, has been attributed to volcanic forcing of climate. A major tropical eruption in 540 CE is thought to have played a key role, but there is no consensus about the source volcano to date. Here, we present evidence for El Chichon in southern Mexico as the most likely candidate, based on a refined reconstruction of the volcano's eruption history. A new chronological framework, derived from distal tephra deposits and the world's largest Holocene beach ridge plain along the Gulf of Mexico, enabled us to positively link a major explosive event to a prominent volcanic sulfur spike in bipolar ice core records, dated at 540 CE. We speculate that voluminous tephra fall from the eruption had a severe environmental impact on Maya societies, leading to temporary cultural decline, site abandonment, and migration within the core area of Maya civilization.