The Deliblato (Banat) Sand Sea, which is one of the largest areas of аeolian sand in Europe, is located near the Iron Gate, which marks the crossing of the Danube River through the biggest gorge of this river. Here, Danubian alluvium has served as the sand source for the Banat Sand Sea, which was formed primarily through southeasterly (Košava) winds. Utilizing a multi-proxy approach, the objective of this study is to gain a better understanding of the environmental dynamics of the Banat Sand Sea. To achieve this goal, we conducted an analysis of an archive representing an approximately 20-m-thick dune formation on the northern edge of this dune field. Using optically stimulated luminescence (OSL) dating, we calculated aeolian sedimentation rates and dune ages. Sand was deposited here approximately between 17 ka and 13 ka. Magnetic susceptibility, grain size, and colorimetric analyses were interpreted in terms of local paleoenvironmental conditions. Calculated sedimentation rates (SR) indicate intensive aeolian deposition during the study period that range from 483 cm/ka to 502 cm/ka. We compared our data with regional and other European archives, as well as with climatic variations recorded in the Greenland ice core North Greenland Ice Core Project (NGRIP).

Weathering has etched and deeply-denticulated the constituent orthopyroxenes, and chlorite has been transformed to vermiculite in the upper 3 m of an aeolian, periglacial sand dune formed in northeastern Indiana about 13,000 b.p. Pyroxene weathering begins with the development of cleavage-parallel etch pits on {010} and {100} surfaces. These pits coalesce and eventually crop out on basal surfaces as denticulations. The mean denticulation size increases logarithmically toward the surface, and the denticulation size of the orthopyroxenes is a quantifiable feature of the weathering process. Ferruginous pendants, microboxworks of iron oxides, and other indications of iron redeposition within the ortho-pyroxene microenvironments were not observed.

Chlorite in the dune has been weathered to vermiculite. The parent chlorite is a high-Fe variety, and the transformation to vermiculate does not involve the development of a chlorite/vermiculite intermediary phase. Fe2+ is oxidized as part of the transformation process and this iron is retained in the sediment as discrete goethite and as crystalline and noncrystalline coatings on the dune grains. The vermiculite from depths shallower than 64 cm is only partly expandable and is completely collapsed by K-saturation or heat treatment. This is a hydroxy-Al vermiculite and its formation is typical of intense weathering under the acid conditions prevalent at the dune surface.

The timeframes of Holocene anthropogenic dune remobilization in Central Europe remain less studied compared to those of Late Glacial climatically controlled dune formation. The present contribution aims to reinforce existing knowledge on the chronology of Late Glacial–Holocene dune activity and stability, as well as to reveal the scale of human impact on dune remobilization. Accelerator mass spectrometry radiocarbon (AMS 14C) dating and calibration of the results are reported from paleosol horizons buried in inland dune deposits that occur in Central and Eastern Poland. Twenty-three new dates are based on charcoal samples collected at 13 sites. From each of the investigated sites, at least one AD date is obtained, indicating that buried paleosols of such young age are far more widespread in Polish dunes than reflected in previous studies. The widespread preservation of these paleosols under cover of aeolian sand reflects the extent of the anthropogenic dune formation phase that peaked during the Medieval and Early Modern periods.

Ubiquitous Holocene dune systems are associated with major west-to-east flowing rivers across the Southern Great Plains (SGP), USA. Critical questions remain as to whether aeolian activity reflects multiple environmental signatures, including increased sand supply from riverine sources. This research focused on the western Red River where geomorphic mapping revealed three terrace levels up to 16 m, buried partially by up to 10 m of aeolian sediments. Pedosedimentary facies analyses of sections and Geoprobe cores extracted from terraces and close-interval optically stimulated luminescence dating of quartz grains revealed two periods of fluvial aggradation at ca. 80 ka to ~5 to 8 m above the Red River forming the Vernon terrace, and at 30 to 13 ka to ~20–15 m, the highest identified Childress terrace. Net degradation of 20 m also occurred between 13 and 7 ka to 4 m below the current channel, reflecting regional fall in the groundwater level. The latest aggradation event, which built the lowest Luna terrace at ~2 m, ended 1.5 to 0.7 ka and was partially buried by fluvial-sourced dunes in the sixteenth and seventeenth centuries. This recent phase of aeolian deposition coincides with a comparatively wet period in the central United States during the Little Ice Age, rather than with regional drying.

Intense aeolian processes in arid and semi-arid environments play an essential role in the preservation and destruction of archeological sites. This is especially the case in the lower basin of the Colorado River at the eastern Pampa-Patagonia Transition of Argentina, as is illustrated by geoarchaeological and chronostratigraphic studies at a mid-Holocene hunter-gatherer site, La Modesta, where aeolian processes strongly influence the archeological record in dune sediments. At La Modesta, surface archaeological materials are numerous and well preserved, although the stratigraphic record is incomplete. Optically stimulated luminescence (OSL) dating of sediments that contain cultural material provides a chronology dating from ca. 8.2 ka but shows one or more hiatuses from ca. 6–2 ka in the sedimentary succession. Intense morphogenesis related to arid climates likely caused gaps in sedimentation, affecting the integrity and resolution of the archaeological record. This study helps explain mid-Holocene archaeological discontinuities throughout central Argentina and highlights the importance of considering taphonomic and geologic biases when dealing with the absence or reduction of the archaeological record in dryland regions.

Coastal dunes along Lake Michigan's eastern shoreline are a unique system comprising perhaps the largest complex of freshwater coastal dunes in the world. Here, we examine the blowouts in this region and determine how they have evolved since the 1930s. We conducted a spatiotemporal analysis of 435 blowouts by comparing repeat aerial images of the coast beginning in 1938. Using an unsupervised machine learning classification known as iso-clustering, we mapped blowout morphologies at three timestamps: 1938, 1986–1988, and 2018. We then compared the blowout geographies through a technique known as a spatial-temporal analysis of moving polygons (STAMP) model, which allowed us to analyze how each blowout changed in time and space. Results show blowouts have contracted ~37% in size since 1938, mostly at the expense of vegetation, with many fragmenting. These findings comport with other regional and global studies detailing a trend in coastal dune stabilization from vegetation and suggest that an increase in precipitation or other environment drivers could be responsible. Moreover, we detected no new blowouts since 1938 along the ~500 km shoreline or on any of the Lake Michigan islands. This suggests blowouts here are artifacts of premodern conditions, perhaps the result of prior stormier or drier eras.

Sequences of quartz-rich coarse (20−63 μm) silt occur in many low- and midlatitude unglaciated arid and semiarid areas and have been termed “desert loess.” The processes by which these deposits are generated have been debated for decades. All hypotheses to explain their origin seek to provide mechanisms for the generation of silt-sized material without glacial grinding, which is the main process involved in the production of coarse silt at high latitudes. Possible mechanisms for the formation of coarse silt in arid regions include derivation from preexisting siltstones, mechanical weathering of silicate rocks, and abrasion of sand grains in active dune environments during intense transport events. Examination of the characteristics of desert loess and field and laboratory experiments to assess the role of dune areas as a source of coarse silt by abrasion and/or resuspension of residual fines suggests that many loess sequences are dominated by locally derived coarse silt. Improvements in the characterization of desert loess particle size, mineralogy, and geochemistry are needed, however, to identify sources and sinks of coarse silt, especially when combined with climatic back-trajectory analysis. Properly scaled experiments and modeling of particle collisions will also help to better quantify the effectiveness of abrasion in the generation of coarse silt in support of field observations.

Russian-thistle (Salsola tragus L.), is a nonnative, C4 photosynthesizing, annual plant that infests disturbed and natural areas in the arid U.S. Southwest. Land managers of natural areas may need to decide whether a S. tragus infestation is potentially harmful and whether it should be actively managed. One factor informing that decision is an understanding of the conditions under which this weed emerges and establishes and how those processes affect where and when infestations occur. We studied S. tragus establishment on aeolian (windblown) sandy soils at Petrified Forest National Park, AZ. Our sites were a previously disturbed sand sheet and a semistabilized sand dune. Measurements in plots on these sites over two growing seasons revealed a similar number of S. tragus seedlings emerging on both sites early in the 2015 growing season. As the season progressed, S. tragus cover (seedling survival and growth) was lower on the sand dune, except for a plot placed entirely on a coppice mound. In 2016, S. tragus seedling emergence and development of cover, measured on plots at both sites, was exceptionally low, as was summer rainfall. A growth chamber assay of seedling emergence from soil and litter samples collected at each site showed emergence was greatest from samples collected where S. tragus litter remained on the soil surface, and otherwise was infrequent. Our study suggests that S. tragus emergence and early establishment are sensitive to low precipitation and that soil-surface microtopography and grass and shrub cover may be determinants of the spatial pattern of infestation on sandy soils. As aeolian sands occur throughout drylands of the U.S. Southwest, deeper understanding of the conditions under which S. tragus seedlings emerge and establish can inform management of this invasive annual in those habitats.

Dunes adjacent to the Snow Water Lake playa in Elko County of northeastern Nevada rise up to ~10 m above the playa surface in seven distinct clusters. The dunes are composed of tan silty loam containing calcite, quartz, plagioclase, and dioctahedral clay. Abundances of trace elements, along with relative proportions of quartz and calcite, are distinct between dunes along the north and south sides of the playa, reflecting proximity to streams draining different lithologies in the neighboring mountains. Luminescence (optically stimulated luminescence and infrared-stimulated luminescence) dating of dune crest samples demonstrates that the last episode of dune accumulation occurred in the mid-eighteenth century. Moisture-sensitive tree ring records from a nearby site indicate that dune accumulation coincided with an interval of below-average precipitation immediately following a very wet decade. This sequence is consistent with models requiring wetter climatic conditions to move coarse sediment onto a playa surface, followed by dune building under drier conditions. Younger luminescence ages from a sand-dominated unit exposed in an arroyo cut through the dunes may reflect a wetter, more erosive climatic regime ca. AD 1800. The Snow Water Lake dunes are currently eroding, signaling a reduction in the amount of sediment reaching the playa.

We present a comprehensive summary of the available palaeoclimate records from India and compare the results from different proxies. The results indicate (i) fluctuating lake levels during the early Holocene. The period of relatively higher lake levels from increased precipitation efficiency was reached only ∼7.2–6.0 cal kyr BP, possibly due to increased contribution from winter rainfall; (ii) the onset of aridity in NW India could have begun as early as ∼5.3 cal kyr BP. Subsequently, there were multiple wet events but of shorter duration and smaller magnitude than during the mid Holocene; (iii) there is evidence of several short term climate events in the proxy record. However, in the absence of a rigorous chronological framework a detailed regional correlation is not possible at this stage. Finally, a comparison between marine and terrestrial records indicates that episodes of strongest and weakest monsoon winds were not always associated with wettest and driest episodes respectively in the NW Indian lakes.

Most inland eolian dunes associated with rivers on the Georgia Coastal Plain probably date to glacial periods. Direct dating of the dune sand by optically stimulated luminescence dating, combined with limiting ages from radiocarbon dating, shows that dunes formed during isotope stage 2, stage 3, the transition between stages 4 and 5, and isotope stage 6 or earlier. Most of the dates indicate dune activity between 30,000 and 15,000 years ago. Holocene activity included limited and local reworking of the crests of some thick dunes along streams that flow from the Piedmont.

Outcrops of buried soils on lake-plains and glacial headlands along Lake Michigan's eastern shore suggest that periodic dune-building has occurred there after relatively long (≥100 yr) periods of low sand supply. We located, described, and radiocarbon dated 75 such buried soils that crop out in 32 coastal dune fields beside the lake. We assume that peaks in probability distributions of calibrated 14C ages obtained from wood, charcoal, and other organic matter from buried A horizons approximate the time of soil burial by dunes. Plotted against a late Holocene lake-level curve for Lake Michigan, these peaks are closely associated with many ∼150-yr lake highstands previously inferred from beach ridge studies. Intervening periods of lower lake levels and relative sand starvation apparently permitted forestation and soil development at the sites we studied. While late Holocene lake-level change led to development and preservation of prominent foredunes along the southern and southwestern shores of Lake Michigan, the modern dune landscape of the eastern shore is dominated by perched dunes formed during ∼150-yr lake highstands over the past 1500 yr.

Aeolian dunes are widely used to reconstruct paleoenvironmental conditions. However, terminal dune fields (ergs) in the coastal desert of southern Peru – where information regarding Quaternary paleoenvironmental conditions is very limited – have until now not been used for paleoenvironmental reconstructions and the time depth of their accumulation is unknown. Here, different estimates are derived to constrain the time depth recorded in the Dunas Pampa Blanca, a terminal dune field in coastal southern Peru. Dune field age is calculated using the volume of the Dunas Pampa Blanca and (i) recent aeolian transport rate in migrating transverse dunes feeding the Dunas Pampa Blanca (derived from digital processing of sequential Landsat and Quickbird images) and (ii) limitations posed by recent fluvial sediment supply to the source of aeolian transport. The resulting maximum age estimate of 70 ± 8 ka (from aeolian transport) compares with a minimum age estimate of 4–75 ka (from sediment supply). However, a minimum age estimate of 110–450 ka is deduced from the tectonic and topographic evolution of the region. This discrepancy contradicts the hypothesis of late Quaternary stability in the Peruvian coastal desert and indicates that recent conditions of aeolian sediment supply and transport are not representative for the late Quaternary.

The early Holocene final drainage of glacial Lake Minong is documented by 21 OSL ages on quartz sand from parabolic dunes and littoral terraces and one radiocarbon age from a lake sediment core adjacent to mapped paleoshorelines in interior eastern Upper Michigan. We employ a simple model wherein lake-level decline exposes unvegetated littoral sediment to deflation, resulting in dune building. Dunes formed subsequent to lake-level decline prior to stabilization by vegetation and provide minimum ages for lake-level decline. Optical ages range from 10.3 to 7.7 ka; 15 ages on dunes adjacent to the lowest Lake Minong shoreline suggest final water-level decline ∼ 9.1 ka. The clustering of optical ages from vertically separated dunes on both sides of the Nadoway–Gros Cap Barrier around 8.8 ka and a basal radiocarbon date behind the barrier (8120 ± 40 14C yr BP [9.1 cal ka BP]) support the hypothesis that the barrier was breached and the final lake-level drop to the Houghton Low occurred coincident with (1) high meltwater flux into the Superior basin and (2) an abrupt, negative shift in oxygen isotope values in Lake Huron.

Discrete dune fields are found throughout much of the Great Plains of North America, and the timing of past dune activity is often used as a proxy for paleoclimate because of the intuitive link between dune activity and a more arid climate. This research suggests that feedbacks in the soil-geomorphic system create a relationship between dune activity and climate that varies both spatially and temporally. Older eolian landforms are more resistant to activation because of the long-term accumulation of finer soil particles in a Bt horizon which retain moisture and anchor the deposit even during more arid times. Conversely, younger deposits lack these fines and are more easily reactivated. This spatially variable relationship is supported by soil stratigraphy, particle size analysis, and optical age control. Additionally, the water retention of the Bt horizons is quantifiably greater than that of the soils found in the younger dunes of the area. This complication in the relationship between eolian activity and climate is important because it suggests that caution is needed when using past dune activity as the lone proxy for paleoclimate.

An equilibrium dune-erosion model is used every six years to assess the capability of the most seaward dune row on the Dutch Wadden islands to withstand a storm with a 1 in 10,000 probability for a given year. The present-day model is the culmination of numerous laboratory experiments with an initial cross-shore profile based on the central Netherlands coast. Large parts of the dune coast of the Wadden islands have substantially different dune and cross-shore profile characteristics than found along this central coast, related to the presence of tidal channels, ebb-tidal deltas, beach-plains and strong coastal curvature. This complicated coastal setting implies that the predictions of the dune-erosion model are sometimes doubtful; accordingly, a shift towards a process-based dune-erosion model has been proposed. A number of research findings based on recent laboratory and field studies highlight only few of the many challenges that need to be faced in order to develop and test such a model. Observations of turbulence beneath breaking waves indicate the need to include breaking-wave effects in sand transport equations, while current knowledge of infragravity waves, one of the main sand transporting mechanisms during severe storm conditions, is strongly challenged by laboratory and field observations on gently sloping beaches that are so typical of the Wadden islands. We argue that in-situ and remote-sensing field observations, laboratory experiments and numerical models need to be the pillars of Earth Scientific research in the Wadden Sea area to construct a meaningful process-based dune-erosion tool.

This article identifies ways to overcome impediments to restoring natural features on developed shores where human-use functions are the dominant driving forces. Suggestions are made for (1) incorporating natural features and natural dynamism into beach nourishment projects; (2) addressing constraints in size and space; (3) reducing the impact of human actions and elements in the landscape; (4) integrating endangered species programmes; (5) overcoming impediments to implementing restoration projects; (6) conducting post-construction evaluations and actions; (7) obtaining public support; and (8) addressing regulatory issues. Beach nourishment projects can better mimic natural landforms, while protecting infrastructure and habitat, creating space for dunes, and providing sediment for dune building. Dunes can have more value as habitat if sub-environments representative of natural gradients are accommodated. Greater human effort will be required to maintain both dynamic and stable zones for habitat, and these zones may be restricted to smaller scales. Controls can be placed on human actions, such as raking the beach, driving on the beach, walking through the dune, emplacing more structures than necessary and introducing exotic vegetation for landscaping. Regulatory restrictions that now prevent environmentally friendly actions can be eased, and adaptive management and education programmes can be implemented.

Redesign of shore protection projects in Mecklenburg-Vorpommern (Germany) is allowing landforms to become more dynamic after centuries of employing structures to increase stability. Current policies are designed to maintain sediment transfers, re-establish wetlands, ensure zero net loss of coastal habitat and apply the user-pays principle for restoring damaged habitat. Projects that achieve new nature-oriented goals include (1) relocating dykes landward or allowing dykes or protective dunes to erode to expose more land to episodic inundation by the sea; (2) reinstating sediment transfers from bluffs to adjacent low-lying shores; (3) increasing sediment transport rates through groyne fields; and (4) removing exotic vegetation from dunes. These actions create new habitat, add portions of the coast to the public domain, and provide a wider buffer against accelerated sea-level rise for developed lands further inland. The management actions have been relatively small in scale, applied where there has been little threat to human facilities and done to achieve specific environmental goals, but they provide examples of workable options to increase the dynamism of stabilized landforms on other exposed coasts. The need to restore natural functions while providing some stability places emphasis on a strategy of controlling dynamism rather than preventing it.