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Areas of shifting sand are important places for testing the effects of abiotic and biotic factors on soil morphology and evolution, where aeolian processes cause dynamic changes in the natural environment. The main aim of the study was to determine the evolution of soils within deflation hollows in shifting sands. In the context of this purpose, representative study areas were selected: (1) a reference surface in a plantation forest with soils undisturbed by aeolian processes - one pedon, (2) an active deflation hollow - two pedons, (3) a deflation hollow stabilized by reforestation (forest planting ca. 30 and ca. 100 years ago - two pedons). Soil morphology and micromorphology as well as several physical and chemical properties were analyzed. In a deflation hollow, the studied soils are found at various stages of development, mostly characterized by a relatively rapid accumulation of soil organic matter. A well-developed buried illuvial B horizon as an 'ortstein' material can limit aeolian erosion to a certain depth, while above these horizons aeolian erosion and accumulation remain active. History of changes in the environment is to a substantial degree reflected in morphology and micromorphology of the studied soils.

In the Laarder Wasmeren area in the western Netherlands, Late Pleistocene cover sands and overlying early Holocene drift sands show various paleosols, which can be characterized as more or less incipient podzols. We dated those soils and sands by radiocarbon analysis and OSL, and we used biostratigraphical dating based on the known chronology of the vegetation history. Apart from Usselo soils of Allerød age, we found early Holocene soils - showing Usselo soil characteristics but with relatively advanced podzolisation - covered by Early Holocene-early Middle Holocene drift sands. We discuss their age and origin, and reflect on the role of fires and ecosystem degradation in the early development of heathland, podzols and drift sands in the Netherlands, prior to any Neolithic farming. We hypothesize about the possible role of Mesolithic man, stimulating habitats for Corylus avellana by burning pine forest, in the longer term inducing the observed ecosystem degradation (transformation of forest into open short vegetation, acidification and concurrent podzolisation, wind erosion). This hypothesis is in line with studies in adjacent NW-European countries, which are reviewed, and an alternative for the theory of Vera (2000), who assumed that open forests and short vegetation resulted from grazing pressure by large herbivores. [ABSTRACT FROM AUTHOR]

Areas of shifting sand are important places for testing the effects of abiotic and biotic factors on soil morphology and evolution, where aeolian processes cause dynamic changes in the natural environment. The main aim of the study was to determine the evolution of soils within deflation hollows in shifting sands. In the context of this purpose, representative study areas were selected: (1) a reference surface in a plantation forest with soils undisturbed by aeolian processes - one pedon, (2) an active deflation hollow - two pedons, (3) a deflation hollow stabilized by reforestation (forest planting ca. 30 and ca. 100 years ago - two pedons). Soil morphology and micromorphology as well as several physical and chemical properties were analyzed. In a deflation hollow, the studied soils are found at various stages of development, mostly characterized by a relatively rapid accumulation of soil organic matter. A well-developed buried illuvial B horizon as an 'ortstein' material can limit aeolian erosion to a certain depth, while above these horizons aeolian erosion and accumulation remain active. History of changes in the environment is to a substantial degree reflected in morphology and micromorphology of the studied soils. [ABSTRACT FROM AUTHOR]

In dendrogeomorphology, abrupt changes in wood anatomy are frequently used to date the exact year of burial and exposure events. However, few studies have addressed the precision and underlying mechanisms of these changes. In a field experiment, performed in a drift-sand area in the Netherlands, we buried the stems of mature pedunculate oak trees ( Quercus robur L.) up to a height of 50 cm and analysed the responses in ring width and earlywood-vessel characteristics, while monitoring the course of temperature above and below the soil surface. After 3 years of stem burial, we found no significant differences in ring width and earlywood-vessel characteristics between control and buried trees both above and below the burial level. Burial however strongly reduced temperature amplitude and the occurrence of sub-zero temperatures around the buried stems. All buried trees formed epitropic roots that grew upward into the new sediment layer, but no adventitious roots were formed on the buried stems. Irrespective of the burial treatments, we found that the mean ring width was largest at the original stem base and lowest at breast height. In contrast, vessel sizes were significantly larger at breast height compared with the stem base. Differences in vessel density barely differed between years and heights. In our field experiment on mature pedunculate oak trees, the burial of stems by 50 cm of drift sand did not induce any local growth suppression or detectable changes in wood anatomy. As wood-anatomical changes in response to burial have previously been reported for trees that had formed adventitious roots, we stress the role of adventitious-root formation as a possible trigger behind the local changes in wood anatomy, reflecting a functional change of a buried stem towards a root. Based on our field experiment, it seems unlikely that years of shallow or moderate burial events (≤50 cm) can be reconstructed using the wood structure of buried stems. As epitropic roots develop quickly after burial, dating such roots may potentially yield better estimates of burial events. Further research on the relation between adventitious root and changes in stem anatomy is needed to ascertain the precision of dating sand-burial events using tree rings. [ABSTRACT FROM AUTHOR]

ABSTRACT The geomorphological analysis of two sections cut into a sandy landscape in north-east Belgium enabled the establishment of a chronology for a sequence of events during the last 15 ka that illustrate the polycyclical nature of the evolution of such landscapes. Field descriptions, analytical sediment and soil characterization, and pollen analysis are combined with the optically stimulated luminescence dating method to unravel the recent geomorphological history of the investigated site. The principal results include apparently discontinuous sand deposition between ∼15 and 12 ka, landscape stabilization and Podzol formation between ∼12 and 1 ka, the development of a drift sand landscape between ∼650 and 200 a, and renewed stabilization over the last two centuries. The results are discussed in the light of climate, land-use and vegetation changes and compared with findings at similar sites in the European Sand Belt. [ABSTRACT FROM AUTHOR]

Question How does pioneer vegetation of acid inland dunes respond to addition of nitrogen (N) and phosphorus (P)? Location Two inland dune reserves in The Netherlands with low and high N deposition. Methods During 2.5 yr, N and P addition (control, N, P, NP) took place in three different vegetation types of inland dunes ( Polytrichum piliferum mats, Campylopus introflexus mats and lichen-dominated vegetation). In each site, changes in the vegetation were recorded in three replicate quadrats of 1 m × 1 m per treatment. Differences in element content of grasses and lichens were recorded, together with vegetation parameters, including cover and height of grasses, bryophytes and lichens. Results In the site with high N deposition, grasses were taller, had higher N:P ratios and a generally lower lichen cover than in the low-deposition area. Experimental N application resulted in higher N and lower base metal concentrations in grasses and an increase in grass cover and size. In contrast, lichens showed a general decline in the N treatment and the lichen:grass ratio decreased. The effect of N addition was larger in the low-deposition area. The P treatment had an opposite effect: lichens increased in size and cover and overgrew grasses, especially when reindeer lichens were present. This suggests that the cryptogam layer was P-limited even in the low N deposition site. Conclusions Pioneer vegetation in inland dunes is susceptible to N and P addition. The results provide evidence for a decrease in lichen cover due to increased N deposition. [ABSTRACT FROM AUTHOR]

Abstract: Close to the village of Pulle (N Belgium), six trenches were opened for archaeological research. This resulted in the discovery of a dense spread of traces of human settlement. Only a relatively small number of artefacts was found, but these allowed attributing the traces to habitation during the Iron Age and Early Middle Ages. In one of the trenches, the level with the archaeological finds was covered by a drift-sand dune. The accumulation of these aeolian sediments presumably put an end to the human occupation. Hence, dating these sediments might provide essential information as to the chronology of the occupational history of the site. Quartz-based optical dating was applied to constrain the timing of sand-drifting at Pulle. All samples showed satisfactory luminescence characteristics and yielded an internally consistent set of optical ages. Within analytical uncertainty, the age results show no increase with depth and do not allow differentiating between distinct phases of sand-drifting. An average age of 1.2±0.1ka was obtained, which is interpreted as an upper age limit for human occupation at the site. The results also illustrate (the limit on) the time resolution that can be achieved through conventional quartz single-aliquot optical dating techniques; considering these limitations, we conclude that the sand-drifting at Pulle occurred during a single, fairly short event in the Early Middle Ages. [Copyright &y& Elsevier]

The article presents a study on predicting the effect of tilling practices on wind erosion activity and the application of the Wind Erosion Prediction System in a sand drift area in The Netherlands. It states that the inland drift sand area in this location forms a unique ecosystem in northern Europe. It mentions that it is essential to investigate how the drift sand areas can be maintained, and how their immobilization by vegetation can be countered by establishing techniques that reactivate the aeolian processes. Four techniques, including rotary cultivator, disc harrow and excavator, and beach sand cleaner, were evaluated during an 8-month experiment at Kootwijkerzand, The Netherlands. The most effective method that was determined is the beach sand cleaner.