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The Holocene evolution of vegetation and environment in the Kleine Nete valley in the coversand region of northeastern Belgium is studied through sedimentological, palynological and macrobotanical analysis of a radiocarbon dated peat sequence. Peat formation started at the beginning of the Holocene in mesotrophic fen conditions. After a period of fast peat growth, the accumulation slowed down and the peat surface became dry in the Middle Holocene. The palynological results are compared with other pollen data from the region, in order to establish a regional pollen biozonation for the Early and Middle Holocene in the Nete Basin. This shows that pine has long been a characteristic element in the Nete Basin. Pine forest expanded immediately after the 11.4 cold event, which is earlier than in the western Scheldt Basin. Pine and birch grew along the valley, possibly also within the peatland. Peaks of microcharcoal, herbs and/or coarse sediment in the peat reflect temporary local forest disturbances in the Early Holocene. Some may reflect small-scale controlled fires induced by hunter-gatherers, although a natural cause seems much more plausible given the dominance of fire-associated pines and increased drought. Pine remained important throughout the Early Holocene. This long-lasting predominance of pine in the Nete Basin, compared to elsewhere in the Scheldt Basin, is likely related to the poor sandy subsoil in the region, which hinders more nutrient-demanding broadleaf trees to overtake. • Peat formed in the valleys of the Nete Basin in the Early to Middle Holocene. • A regional pollen biozonation is established for the Nete Basin. • Pine dominated the forests during most of the Early Holocene. • Charcoal, herb and sand peaks reflect local forest disturbance. [ABSTRACT FROM AUTHOR] more...

At the transition between the Scheldt valley and the Campine microcuesta near Antwerp, two separate organic deposits are present in the subsoil. Sedimentological, macrobotanical and palynological analyses from two cores are used to reconstruct the evolutions of the local depositional and ecological environment, as well as the regional vegetation. An age-depth model based on radiocarbon dates allows to frame those evolutions chronologically. During the Weichselian lateglacial, a mesotrophic lake was filled with peat during GI-1. The sand input indicates continued aeolian activity, also during forested phases. This peat was covered by wind deposits during GS-1. From the start of the Holocene onwards, a river channel in the Opstal Valley started to fill with peat in a mesotrophic fen. Pollen records show a temporary opening of the regional forest, that can be linked to the 11.4 ka event. The peat dried out around 11,000 cal BP and wetter conditions returned by the beginning of the Middle Holocene, with the development of an alder/birch carr. Unlike the Scheldt valley, the Opstal valley was not under tidal influence in the Middle Holocene. After ca. 6000 cal BP, the valley was part of the coastal peatlands that evolved from mesotrophic fen into oligotrophic bog. • A small lateglacial lake was present at the foot of the Campine microcuesta. • The lake was filled with mesotrophic peat and aeolian sand. • A small river channel was filled with peat and dried out during the Early Holocene. • The Preboreal oscillation is visible in the pollen diagram. • Wet conditions returned in the Middle Holocene with alder carr to fen vegetation. [ABSTRACT FROM AUTHOR] more...