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The Pacific coast of eastern Japan contains specific aeolian landforms of geomorphological interest in terms of their formation processes in humid climates and Holocene paleoenvironments. Wind erosion landforms, characterised by blowouts, were observed at the heads of coastal cliffs which consisted of marine gravel sediments, weathered volcanic ash layers (WVALs) and black soil layers (BSLs). The blowouts were accompanied by downwind tephric loess dunes. We analysed the physicochemical properties of the WVAL, BSL and dune sediment samples. The results revealed that clay and silt contents in dune sediments were 5–48% and 20–35%, respectively. The fine particles were in the form of aggregates in the WVALs, BSLs and dune sediments, with contributions from andic properties. WVAL and BSL aggregates were prone to movement in saltation, depositing into the dunes in a formation process similar to that of clay dunes in semiarid zones. The tephric loess dunes were characterised as clay dunes based on their high clay and silt contents. In addition, the dunes were characterised by durable aggregates derived from short-range-order minerals, such as allophane. The prevailing northeasterly winds caused by intense low pressures were responsible for dune formation in the study areas. Radiocarbon dating revealed two active wind periods. The first was approximately 1005–895 cal. BC to 358–281 cal. BC, and the second was 771–886 cal. AD to 1021–1155 cal. AD. [ABSTRACT FROM AUTHOR]

ABSTRACT Fieldwork investigations and stratigraphic analyses in the Parnaíba Basin, northern Brazil, reveal the interaction of the uppermost part of the Triassic Sambaíba aeolian dune field (erg) system with the latest Triassic–earliest Jurassic Mosquito lava flows. The lava flows originated as part of the Central Atlantic Magmatic Province (CAMP, ~201 Ma) and covered the aeolian system, allowing almost complete preservation of large‐scale in situ aeolian bedforms, even preserving lee‐ and stoss‐side. During the emplacement, the lava flows interacted with unconsolidated aeolian sediment, generating sediment–lava deformation features that are preserved at the interface between these units. This occurrence attests to arid conditions in the low latitudes of Gondwana at the Triassic–Jurassic transition. [ABSTRACT FROM AUTHOR]

The use of construction waste in creating concrete and mortar is an important process that not only offers economic benefits but also helps protect the environment by reducing waste in rural and urban areas. This experimental study aims to investigate the effect of adding crushed ceramic waste (CCW) and crushed brick waste (CBW) on the bulk density, workability, compressive and flexural strengths, water absorption and microstructural properties of dune sand mortar. To determine changes in porosity, the study uses the mercury intrusion porosimetry technique to measure porosity and pore size distribution. Scanning electron microscopy and energy-dispersive X-ray spectroscopy analyses are conducted to examine the microstructure and size of the voids using an electron microscope, and photographs of voids in the mortar matrix are taken. By replacing 15% of the sand with CCW and CBW, the compactness and mechanical strength of the dune sand mortar are enhanced, increasing the dynamic modulus of elasticity by around 29 and 26%, respectively. This is due to the pozzolanic activity of these residues, which mainly occur in the form of medium and small capillaries in all the mortars studied, reducing the diameter of the pores. [ABSTRACT FROM AUTHOR]

Accurate assessment of bedload transport is a challenging task due to its variable nature in space and time. Bedload transport measurement techniques can be divided into two categories of direct and indirect methods. The focus of this study is on dune tracking as an indirect measurement method that has received much attention in recent years. However, a comprehensive workflow that allows the integration of this method into a routine measurement operation instead of or jointly with the direct sampling method has not been implemented yet. During a three-day measurement campaign conducted in the Rhine River, a detailed workflow for performing bedload transport measurements using the dune tracking method was introduced. Dune tracking validation was thoroughly evaluated, with significant efforts to simultaneously collect data using direct sampling. Direct measurements of bedload transport showed higher and more variable rates compared to dune tracking estimates. It was assumed that finer sediment fractions, moving as patches or small-scale superimposed bedforms were presumably not captured by the dune tracking. However, their significant contribution to bedload transport suggests that dune tracking estimates may have been underestimated. Further research is needed to explore how varying flow and sediment conditions affect bedload transport modes and measurement methods comparability. [ABSTRACT FROM AUTHOR]

The Xerces Blue (Glaucopsyche xerces) is considered to be the first butterfly to become extinct in historical times. It was notable for its chalky lavender wings with conspicuous white spots on the ventral wings. The last individuals were collected in their restricted habitat, in the dunes near the Presidio military base in San Francisco, in 1941. We sequenced the genomes of four 80- to 100-year-old Xerces Blue, and seven historical and one modern specimens of its closest relative, the Silvery Blue (Glaucopsyche lygdamus). We compared these to a novel annotated genome of the Green-Underside Blue (Glaucopsyche alexis). Phylogenetic relationships inferred from complete mitochondrial genomes indicate that Xerces Blue was a distinct species that diverged from the Silvery Blue lineage at least 850,000 years ago. Using nuclear genomes, both species experienced population growth during the Eemian interglacial period, but the Xerces Blue decreased to a very low effective population size subsequently, a trend opposite to that observed in the Silvery Blue. Runs of homozygosity and deleterious load in the former were significantly greater than in the later, suggesting a higher incidence of inbreeding. These signals of population decline observed in Xerces Blue could be used to identify and monitor other insects threatened by human activities, whose extinction patterns are still not well known. [ABSTRACT FROM AUTHOR]

Accurate mapping plays a crucial role in the management of natural hazards, particularly in the monitoring of sand dune movement. In this research, we focused on modeling sand dune encroachment in a specific study area situated between latitudes 25° 26' 30" N and 27° 49' N, and longitudes 27° 28' E and 31° 08' E, located in the central Western Desert of Egypt. To accomplish this, we employed advanced machine learning techniques, such as linear support vector machines (SVM), and integrated machine learning algorithms with spatial data types using GIS and R software. To identify dune accumulations from various multispectral sensors, we proposed a novel index called the Drifting Sand Index (DSI). The effectiveness of the DSI was demonstrated, highlighting its significant potential for mapping and monitoring dunes in the study area. Through the utilization of different data sources and field surveys, we identified approximately 150 sand dune locations in the study area. For the sand dune encroachment modeling, we generated nine variables, including slope, aspect, altitude, lithology, distance to roads, normalized difference vegetation index (NDVI), land use/land cover (LULC), wind speed, and direction and soil properties. The results obtained from the DSI indicated that the movement of dunes in the study area ranged approximately 4.9 m/yr towards the southeast. By employing the SVM model, we were able to produce a comprehensive map illustrating the risks associated with sand dune encroachment. The sand dunes hazard zones were classified into five categories: very low (47.1 km2), low (11285.7 km2), medium (356.8 km2), high (9519.1 km2), and very high-risk (16552.1 km2) zones. The area under curve (AUC) approach has been applied to evaluate, validate, and compare the SVM model performance. The results indicated that AUC values for nine MLTs range from 95.1%. The RMSE value for the applied MLT was determined to be 0.391, indicating a significant agreement between the model and reality..The information derived from this study will contribute to the achievement of sustainable development goals and the preservation of the environment. [ABSTRACT FROM AUTHOR]

Moroccan historian Abdallah Laroui's L'histoire du Maghreb: Un essai de synthèse (The History of North Africa: An Interpretative Essay) (1970) offers a prime example of a former colonized subject's effort to decolonize the discipline of history. Scholars of Arab and North African historiography have either dismissed it as an ideological text or lauded it as an ambitious attempt to call out French hegemony in its former colonies. This essay offers an alternative reading that underlines its social and political dimensions in the context of Moroccan nation-building in the 1970s. It puts Laroui in dialogue with other intellectual voices of this time to illustrate the originality of his call for the public role of historians of decolonization. The article also discusses Laroui's political withdrawal in the next decade and his shift from Marxism to liberal state reformism. [ABSTRACT FROM AUTHOR]

Coastal sediment stratigraphies, their physical properties and microfossil assemblages are commonly used to reconstruct sea-level change. However, coastal sediments are affected by tidal, wave, aeolian, and overwashing processes at a range of elevations both within and above the tidal frame which means that their sea-level signatures may not always be clearly identified. Saltmarsh is a common coastal sedimentary environment along the Atlantic-facing coastline of northwest Ireland where bedrock headlands and an archipelago of small offshore islands have provided accommodation space for aggradational Holocene sediment sequences. A 2.85 m-long sediment sequence was investigated at Cloughglass, northwest Ireland. This shows weathered granite bedrock overlain by glacigenic cobbles and then in situ Pinus stumps within humified peat that is exposed in the upper foreshore. Above this, organic-rich and laminated saltmarsh sediments are arranged in packages (20–80 cm thick) bounded by undulating erosional surfaces. The saltmarsh sediments are unconformably overlain by a palaeosol (30 cm thick) and 1.5 m of recent dune sand. Sediment samples were removed at 5 cm intervals through the entire logged section and analysed for grain size properties, combustible organic content, CaCO 3 content, and microfossil assemblages. Five samples were dated by the AMS 14C method. Results show organic sediment accumulated around the pine tree stumps at ∼4400 cal yr BP but that later sedimentation was episodic, as evidenced by erosional surfaces throughout the saltmarsh part of the succession that may correspond to episodic storms or flood events. Three microfossil biostratigraphic zones are identified which broadly correspond to the sediment stratigraphy. The lowermost zone has poor preservation. The middle zone contains several halophytic species in low abundance but is dominated by the ubiquitous diatom Achnanthidium minutissimum. The uppermost zone is less diverse, with low but consistent abundance of predominately freshwater species and those that can tolerate brackish conditions. Integrating these results suggests that late Holocene coastal erosion and sea-level rise brought the coastline closer to the site over time, with a concomitant increase in wave and tidal influence as recorded in both sedimentary structures and biofacies. Subsequently, the land surface became stabilized with development of a dune palaeosol and decreased abundance of A. minutissimum. This evolutionary history reflects changing patterns of wave exposure and sediment supply as a result of changes in sand accumulation around the surrounding bedrock islands. Thus, the coastal stratigraphy more strongly reflects local sediment dynamics and accommodation space rather than regional sea-level change in the late Holocene. [ABSTRACT FROM AUTHOR]

In subsurface energy extraction, permeability or conductivity is the vital parameter for quantifying fluid flow in porous media. Three-dimensional digital core technique is widely used to calculate flow parameters and to analyze the internal structure and properties of rocks. However, one major problem is its high computational cost associated with fine-scale simulation of porous media, especially for large and complex rock samples. In this study, we propose to use subvolume properties to increase computational efficiency. Specifically, we first construct digital cores of dune sand and sandstone by CT scanning technology, and divide the whole core into multiple subvolumes and calculate their permeabilities. Then, we reassemble the subvolumes and compute the permeability for the whole core. This approach may lead to underestimation as the connectivity between subvolumes could be lost. To address this issue, we divide the whole core into different-sized subvolumes, and then use curve fitting to deduce the permeability of whole rock sample via extrapolation. The results show that the proposed method has improved accuracy, and is significantly faster than simulating the whole digital core, since the computation on subvolumes can be easily parallelized. This approach provides new ideas for accurate and efficient permeability estimation for digital porous media. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to determine the distribution pattern of soil water in desert dunes, to clarify the relationship between soil water and various terrain and vegetation factors, so as to provide scientific and reasonable suggestions for the protection and reconstruction of vegetation in desert areas. [Methods] There were four different micro-landforms, including windward slope, leeward slope, hill top and bottom. The soil moisture was divided into surface (0-40 cm), middle (40-200 cm) and deep (200-300 cm) layers. The distribution characteristics of soil water on different micro-landforms and depths in Gurbantunggut Desert were studied on the small scale. Generalized linear model, generalized additive model and random forest were used to study the relationship between soil moisture and topographic- vegetation factors. [Results] (1) The soil moisture on the windward slope and the bottom of the hill was higher than that on the lee slope and the top of the hill at different depths. There were significant differences of surface soil moisture between the lee slope (including the top and bottom of the hill) and the windward slope. (2) The effect of topographic factors on soil moisture was greater than that of vegetation factors. The main factors affecting surface soil water were slope and slope direction. The main factors affecting middle and deep soil water was shrub cover. (3) The fitting effect of the random forest was significantly higher than that of the generalized linear model and generalized additive model. [Conclusion] As for soil moisture on different micro-landforms, topographic factors have a greater impact on mobile dunes in Gurbantunggut Desert than vegetation factors. Slope and slope direction have the important influence on surface soil moisture. Shrub cover has a major effect on middle and deep soil moisture. [ABSTRACT FROM AUTHOR]

In this study, the application of microbially induced carbonate precipitation for coastline protection was investigated. Untreated, moderately, and heavily cemented near-prototype dunes were fabricated in the largest wave flume in North America at the O.H. Hinsdale Wave Research Laboratory at Oregon State University. Dunes were stabilized with two treatment application systems known as surface spraying and prefabricated vertical drains. Untreated and stabilized dunes were subjected to waves similar to Hurricane Sandy conditions recorded in New Jersey in 2012. Laboratory tests and in situ assessments were performed to quantify the improvement of mechanical properties of soil and investigate the performance of dunes subjected to extreme wave actions. Post-treatment cone penetration test sounding results indicated a significant cone tip resistance that was controlled by carbonate content and cementation distribution pattern. Similarly, monitoring the changes in the morphology of dunes demonstrated that the shear strength, cementation level, and cementation distribution pattern control the equilibrium beach profile, erosion rate, and mass loss. [ABSTRACT FROM AUTHOR]

Toe fringes are a key innovation for sand dwelling lizards, and the relationship between toe fringe function and substrate properties is helpful in understanding the adaptation of lizards to sand dune environments. We tested the sand burial performance of Phrynocephalus mystaceus on different sand substrates with toe fringe manipulation, with the aim of assessing whether the function of the toe fringes shifts under different substrate properties, especially in highly mobile substrates. The sand burial performance of P. mystaceus was influenced by substrate properties in relation to the toe fringe states of the lizard. After removal of the bilateral toe fringes, the sand burial ability score of P. mystaceus was significantly higher on sand substrates below 100 mesh than on native sand substrates. As the angle of stability of the substrate properties decreased, the sand burial performance of the lizard was even better after the bilateral toe fringes were removed. The results of the LASSO model and the path analysis model showed that the stability angle provided the opposite effect on sand burial performance in different toe fringe states. These results further suggest that the sand burial function of toe fringes may not be suitable for highly mobile sand substrates. It remains to be tested further whether the function of toe fringes is more important for running on sand. [ABSTRACT FROM AUTHOR]

ABSTRACT Wind‐driven sediment transport drives significant landscape evolution in arid regions. Wind‐blown sand can form large dunes, or can erode exposed surfaces via abrasion. Previous works on aeolian abrasion have focused on the geomorphological features resulting from abrasion (for example, ventifacts and yardangs) through both field and wind‐tunnel experiments. However, relatively little attention has been given to how abrasion varies spatially as sand flux converges on a sand sink, such as a dune field. This work studied an arid landscape using field measurements and collected weather data to quantitatively measure how abrasion varies in space around the Ibex Dune Field. From March 2021 to October 2022, the wind conditions at two separate locations in the region were monitored, saltating sand flux was captured using fully rotating sediment traps, ventifacts were mapped along several transects, and abrasion‐related mass loss on mounted gypsum plaster samples was measured. These results suggest that the magnitude of abrasion is approximately inversely proportional to the distance away from the dune field, increasing in magnitude as sands converge and fluxes increase at the dune field sink. Comparison between modern winds and ventifact orientations suggests that additional complexity, not aeolian processes alone, may be shaping the morphology of surface cobbles. [ABSTRACT FROM AUTHOR]

The evaluation of genetic diversity is important for the conservation of species. However, changes in genetic diversity during conservation are complex processes that depend on the characteristics of the species and environment. To evaluate the changes in genetic diversity from decline to recovery, we surveyed the coastal herb Calystegia soldanella in areas with varying degrees of non‐coastal plant invasion. First, to evaluate genetic diversity before the conservation measures, the spatial clonal structure of adults was investigated in a population invaded by non‐coastal plants. Second, to evaluate genetic diversity after the conservation measures, the regenerated individuals were investigated in the restoration plot. Moreover, to predict future genetic diversity without conservation measures, the effects of non‐coastal plant invasion on the production and genetic diversity of seeds were investigated using individuals from areas with various levels of non‐coastal plant invasion. In the adult population, 16 genets were identified in an 80 m × 4 m area. The maximum genet size was 30.3 m, suggesting the importance of clonal reproduction for population maintenance. In the restoration plots comprising 10 m × 10 m × 3 replicates, many seedlings (1.14 ramets/m2) emerged, resulting in high clonal diversity compared to that of the adult population. Therefore, the biomass and genetic diversity were rapidly restored at the beginning of the conservation practice. Non‐coastal plant invasion did not affect the genetic diversity of the seeds. However, it significantly reduced seed production. This suggests that non‐coastal plant invasion reduces sexual reproduction, resulting in the long‐term loss of genetic diversity. [ABSTRACT FROM AUTHOR]

The characteristics of fan sediment in the distributive fluvial system are evaluated based on a thorough analysis of modern silt in the Guertu river distributive fluvial system, as well as data obtained from UAV aerial photography and satellite remote sensing. The Guertu River Distributive Fluvial System (DFS) is classified into three stages, namely "proximal," "middle," and "distal," based on the examination of river morphology, sediment variations, sedimentary attributes, and other relevant aspects throughout different sections of its tributaries, from the source to the mouth. At the upstream section of the downstream fining sequence, the slope is the steepest and the hydrodynamic conditions are intense, resulting in the formation of a predominantly big gravel braided river. The river bed section has a morphology resembling a combination of a "V" and a "U" shape. It is characterized by a narrow and deep configuration, with a relatively short breadth. The sediment primarily consists of medium to large-sized gravel with minimal sand content. The gravel exhibits good roundness and displays a considerable degree of orientation. The primary microfacies present are braided channel and flood plain. The slope of the central area is decreased in comparison to the nearby end, primarily due to the presence of extensive braided rivers. The river bed has a greater width, with minor eolian dunes visible in the river channel. The gravel particles are predominantly fine to medium in size, and there is an increased amount of sand present. The predominant microfacies are braided channels, floodplains, and eolian dunes. At the distal end, the slope is minimal, the landscape is level, the braided river transitions into a meandering river, the sediment consists primarily of sand, and the signs of bioturbation are clearly visible. The primary microfacies consist of braided channels, meandering channels, floodplains, eolian dunes, lakes, and swamps. [ABSTRACT FROM AUTHOR]

Coastal dunes are characterised by strong gradients of abiotic stress, typically increasing in severity from inland areas towards the shoreline. Thus, dune gradients represent unique opportunities to study intraspecific responses to environmental changes and to investigate which factors drive community change. This study aims to examine functional trait variation in two coexisting species in response to environmental changes along a dune gradient in NW Spain. Trait convergence was also investigated and compared between both ends of the gradient. We measured functional leaf traits related to plant efficiency in the use of light, water and nutrients, also possible stressors (salt content and pH) and availability of limiting resources (water and nutrients) in the soil. Most soil variables showed changes following a non‐directional gradient. Differences in soil variables were site specific and depended on growth of the study species. Structural and functional traits depended on species and/or plant position on the gradient, except for effective quantum yield of PSII and leaf δ15N. The pattern of variation was mostly directional for reflectance indices related to leaf physiology. Multivariate analyses showed significant interspecific differences in the set of traits they exhibited along positions in the gradient. Species also differed in the combination of traits selected under given environmental conditions. Coexisting species display a specific set of traits that reflects different strategies to environmental stress. Our study highlights the overly simplistic nature of some previous studies that assume dune gradients are monotonically directional, without considering that these gradients may be differentially modified by species activity. [ABSTRACT FROM AUTHOR]

Plant traits and connectivity influence habitat usage, but fine‐scale ecological characteristics that determine fossorial animal movement patterns remain unclear. To understand the influence of landscape connectivity on movement behaviour, we examined vegetation characteristics relative to tracks between vegetation hummocks left by the short blind dart skink, Typhlacontias brevipes, a fossorial lizard inhabiting dunes of the Namib Desert. We measured characteristics of >700 plant hummocks and 293 T. brevipes tracks. Tracks were relatively direct from hummock to hummock (median straightness = 0.94). Vegetation hummocks with tracks were significantly larger than hummocks without tracks, indicating that vegetation size was the most important factor we measured in predicting track occurrence and was more important to skinks than the distances between hummocks, with only 24% of tracks occurring between nearest neighbouring vegetation hummocks. Network clusters consisting of as many as 15 vegetation hummocks were connected by tracks. Skink tracks had a median length of 815 cm and were oriented primarily from 0° to 30°. Our study highlights the importance of vegetation size to fossorial skinks and raises questions regarding other vegetation features that might influence the movement and ecology of fossorial lizards. [ABSTRACT FROM AUTHOR]

Grain sizes of Martian sand dunes are critical sedimentological data on sand provenance and transport pathways. Thermal inertia values are used to characterize the grain sizes of dune sand. Most early characterizations involved single dune fields. Recent work based on global data sets has provided more wide‐spread dune sand locations, though these data sets include the non‐sandy interdune areas. To provide a more accurate grain size characterization, we leverage a global thermal inertia data set, a global dune database and a global imaging mosaic to develop a freeware‐based methodology for deriving grain sizes. This methodology involves delineation of sand‐only areas within dune fields and collection of thermal inertia values from those areas. We consider a unimodal histogram of values with a mode <∼350 thermal inertia units (J m−2 K−1 s−1/2) to imply an effective exclusion of non‐sand surfaces. Application of this methodology to dune fields for which thermal inertia values have been previous derived shows our results fall within the envelope of those values. We apply our methodology to tropical dune fields on Mars for which Dust Cover Index data imply dust‐free surfaces. Conversion of these thermal inertia values to sand grain sizes yields a range of sand classifications of fine sand to granules. Comparison of sand size classifications with geographic location shows grain size ranges that are distinctive by location, consistent with local sourcing. This work points toward geographically diverse sand formation mechanisms yielding diverse grain sizes, while providing a freeware‐based and thus widely accessible method for expanding the derivation of these critical data. Plain Language Summary: Knowing the sizes of sand grains on Mars provides information on the history of that sand, such as where it came from and how far it has traveled to where it is now. Sand grains of different sizes respond to heat differently, with larger sand grains heating up and cooling down more slowly than smaller grains or dust. This response to heating—termed "thermal inertia"—has been used for decades to estimate the grain sizes of dune sand on Mars. However, previous methods have been focused on only a few dune fields at a time. To increase the amount of grain size data we can collect from sand dunes on Mars, we have developed a freeware‐based approach using global data sets and software that are accessible to anyone. Applying our approach to all the dunes for which grains sizes based on thermal inertia were previously derived, we show that our values are similar to those from the previous work. Applying our approach to 75 dune fields on Mars, we see different dune fields have different grain sizes, which suggests different sand formation mechanisms in these different locations. Thus, our freeware‐based approach provides an accessible opportunity to learn about sand characteristics and sand histories across Mars. Key Points: We develop and test a fully freeware‐based method for estimating grain sizes of Martian dune sand and apply it to tropical dune fieldsOur grain size values fit within the envelope of grain size values from decades of previous work, indicating the validity of our methodOur results also reveal geographic variability in grain sizes, indicating geospatial variability in sand‐forming mechanisms on Mars [ABSTRACT FROM AUTHOR]

Glehnia littoralis is a perennial herb found in coastal sand dunes throughout East Asia. This herb has been reported to have hepatoprotective, immunomodulatory, antioxidant, antibacterial, antifungal, anti-inflammatory, and anticancer activities. It may be effective against hepatocellular carcinoma (HCC). However, whether this has been proven through gene-level RNA-seq analysis is still being determined. Therefore, we are attempting to identify target genes for the cell death process by analyzing the transcriptome of Hep3B cells among HCC treated with GLE (Glehnia littoralis extract) using RNA-seq. Hep3B was used for the GLE treatment, and the MTT test was performed. Hep3B was then treated with GLE at a set concentration of 300 μg/mL and stored for 24 h, followed by RNA isolation and sequencing. We then used the data to create a plot. As a result of the MTT analysis, cell death was observed when Hep3B cells were treated with GLE, and the IC50 was about 300 μg/mL. As a result of making plots using the RNA-seq data of Hep3B treated with 300 μg/mL GLE, a tendency for the apoptotic process was found. Flow cytometry and annexin V/propidium iodide (PI) staining verified the apoptosis of HEP3B cells treated with GLE. Therefore, an increase or decrease in the DEGs involved in the apoptosis process was confirmed. The top five genes increased were GADD45B, DDIT3, GADD45G, CHAC1, and PPP1R15A. The bottom five genes decreased were SGK1, CX3CL1, ZC3H12A, IER3, and HNF1A. In summary, we investigated the RNA-seq dataset of GLE to identify potential targets that may be involved in the apoptotic process in HCC. These goals may aid in the identification and management of HCC. [ABSTRACT FROM AUTHOR]

Coastal ecosystems provide critical storm and flood protection but are rapidly degrading worldwide, making their restoration urgent. We evaluated whether successional facilitation, where pioneers facilitate climax species, could be leveraged to accelerate coastal dune revegetation. A survey spanning 270 km of Southeast U.S. coastline revealed that Panicum amarum (bitter panicum) supported higher plant richness than Uniola paniculata (sea oats) and that sea oat cover was 230% greater on mature dunes than disturbed dunes, suggesting bitter panicum functions as a pioneer and sea oats as a climax species. A reciprocal transplant experiment confirmed this interpretation: bitter panicum stem production and height fell by 37% and >20 cm, respectively, when planted proximate to sea oats versus in isolation, whereas sea oats produced 38% more and >12 cm taller stems when planted proximate to bitter panicum versus in isolation. A second experiment evaluating the density‐dependence of this facilitative interaction revealed that sea oats transplanted into low densities of bitter panicum grew >15% taller than isolated and high‐density treatments. However, within 7 months, wave inundation eliminated over 60% of propagules in both experiments. To explore foredune inundation frequency and its implications for dune revegetation, we applied empirical wave runup models at 101 locations throughout Volusia County, Florida. While disturbance frequency varied seasonally and annually, sites with low dune crests and steep beach slopes experienced frequent inundation (>50 events/year). Given the interactions between geomorphology and vegetation success, we present a decision matrix to guide managers in determining optimal revegetation methods tailored to project goals and site conditions. [ABSTRACT FROM AUTHOR]

Stalter, R. and Lonard, R.I., 2024. Biological flora of sand dunes on the northwest Pacific coastline of North America: Ammophila arenaria (L.) Link and Ammophila breviligulata Fernald. Journal of Coastal Research, 40(5), 994–1000. Charlotte (North Carolina), ISSN 0749-0208. Ammophila arenaria, native to European coastal dunes, was initially introduced on the Pacific coast of North America in 1868, while A. breviligulata was introduced to temperate regions along the Pacific coast in 1935. Both rhizomatous taxa are often dominant on coastal foredunes. Ammophila arenaria has short, thick rhizomes, while A. breviligulata has a spreading rhizome system. Both species have been introduced for sand stabilization and shoreline protection. The primary method of reproduction for both taxa is fragmentation of rhizomes. Ammophila breviligulata aggressively competes with A. arenaria and is now dominant over A. arenaria at many sites. The introduction of A. arenaria and A. breviligulata has contributed to dense cover on foredunes and a concomitant decline of native plants and animals, especially those dependent on open sand habitats. Ammophila breviligulata successfully competes with A. arenaria, which has reduced dune heights, increasing the number of areas vulnerable to storm surges and dune erosion. [ABSTRACT FROM AUTHOR]

Wang, P.; Royer, E.L.; Jackson, K., and Gutierrez, S., 2024. Impacts of Hurricane Ian along the low-lying southwest Florida coast (USA) in 2022: Lessons learned. Journal of Coastal Research, 40(5), 827–851. Charlotte (North Carolina), ISSN 0749-0208. Hurricane Ian made landfall in the low-lying, densely populated, and developed southwestern Florida coast on 28 September 2022 as a large and slow-moving category 4 hurricane. Various U.S. federal and state agencies collected a large and comprehensive data set, including pre- and poststorm airborne LIDAR topography, in situ water level and wave measurements at numerous locations before, during, and after the storm, and poststorm high-water marks over a large area. This study reports results from a series of poststorm field investigations including ground observations of beach-dune erosion and deposition, catastrophic damage to various infrastructure, and widespread distribution of non-biodegradable materials washed into the estuary and numerous mangrove islands. Hurricane Ian induced large-scale inundation in low-lying southwest Florida, submerging all the barrier islands bordering Charlotte Harbor estuary, all the islands within the estuary, and up to 5 km into the mainland. Dense tree-type vegetation limited the landward penetration of beach-dune erosion and overwash deposition along the barrier islands. Net sand-volume loss from the beach-dune system ranged 10–25 m3/m and was controlled by the deep submergence of the system during the peak of the storm. The extremely high storm surge of up to 5.2 m above mean sea level generated by Hurricane Ian caused severe damage to the built environments over a large area. High storm waves superimposed on the elevated water level, reaching 1.2 m at the seaward edge of vegetated dunes, contributed to the destruction along the barrier islands. Hurricane Ian distributed a tremendous amount of non-biodegradable artificial debris over a large area and into sensitive natural environments, including numerous mangrove islands, barrier-island interior wetlands, and the estuary waterbody. Measures to prevent materials such as single-use plastics, insulation fibers, and household appliances from being washed into sensitive environments should be a significant part of prestorm preparation. [ABSTRACT FROM AUTHOR]

Greipsson, S.; Stover, K.; Whitney, S., and McElroy, T., 2024. Arbuscular mycorrhizal fungi and soil fungi associated with Uniola paniculata L. (sea oats) on restored and natural sand dunes on the Georgia Coast, U.S.A. Journal of Coastal Research, 40(5), 875–886. Charlotte (North Carolina), ISSN 0749-0208. Coastal sand dunes are fragile ecosystems that serve as natural defenses to protect barrier islands and the adjacent mainland during severe storms. A high frequency of disturbances may result in dune erosion. Several strategies have been used for coastal restoration; however, previous practices often lack the connection between plants and below-ground microbial communities. Symbiotic arbuscular mycorrhizal fungi (AMF) are beneficial in supplying a range of limiting nutrients to the host plant while improving dune stability. This study assessed the diversity of the indigenous AMF and soil fungal communities associated with Uniola paniculata L. (sea oats) on natural dunes and restored dunes at Jekyll and Tybee Islands on U.S. Georgia's coast. The phosphorus (P) concentrations of dune sand were also analyzed. At each site, samples were collected from 10 dune ridges that were randomly selected along a 100-m transect where sea oats were growing. The genomic DNA was extracted from 60 sand and sea oats root samples. A total of 13 amplicon sequence variants of AMF were identified; seven were classifiable to the species level. The most abundant genera of AMF were Glomus; the most abundant species were unclassified Glomus spp., followed by Glomus custos and G. deserticola. Using the Sorensen-Dice coefficient, the study showed that AMF assemblages of the natural dunes of both sites shared a high similarity (0.73). However, AMF assemblages of the Jekyll Island natural site had no (0) similarity to Jekyll Island restored site 1. The greatest number of classes of soil fungi were found at Jekyll Island's restored site 1 (18 classes); conversely, the lowest number was found at Jekyll Island's natural site (nine classes). Natural dunes contained significantly greater levels of P in the sand compared with restored dunes. These findings demonstrate the need to manage sand material and AMF assemblages during coastal dune restoration. [ABSTRACT FROM AUTHOR]

This article provides information about Wyoming jade, specifically the two types of rock it is composed of: jadeitite and nephrite. Nephrite is the more common type and is known for its toughness and ability to be carved into delicate shapes. Wyoming jade is found in various mountain ranges in central and eastern Wyoming, particularly in areas where crustal plates have collided. The formation of jade in this region is believed to be a result of hydrothermal fluids interacting with amphiboles and crystallizing rapidly in a tectonically active environment. Detrital jade, or jade float, is also found in alluvial deposits downstream from primary deposits. [Extracted from the article]

This research focuses on tackling the issue of fertile land turning into desert in arid regions. It proposes a solution involving financial incentives based on payment for ecosystem services (PES) to encourage the transformation of privately owned sand dunes into agroforestry systems. Under the proposed mechanism, farmers plant Acacia nilotica trees along with pearl millet on sand dunes, which provides resilient economic returns in regions with harsh climatic conditions. In addition, acacia trees help to prevent crop damage on neighboring farms through stabilizing sand dunes and serving as shelterbelts. A dynamic optimization model of land-use decisions between open millet farming and acacia-based agroforestry derives optimal afforestation of sand dunes under varying PES payments, crop incomes, and farm size endowments. Results suggest that such agroforestry systems can be effective towards preventing the spread of desertification in arid regions. Further, PES incentives can improve agroforestry uptake as well as augment farmers' livelihoods. [ABSTRACT FROM AUTHOR]

Spatial accurate mapping of land susceptibility to wind erosion is necessary to mitigate its destructive consequences. In this research, for the first time, we developed a novel methodology based on deep learning (DL) and active learning (AL) models, their combination (e.g., recurrent neural network (RNN), RNN-AL, gated recurrent units (GRU), and GRU-AL) and three interpretation techniques (e.g., synergy matrix, SHapley Additive exPlanations (SHAP) decision plot, and accumulated local effects (ALE) plot) to map global land susceptibility to wind erosion. In this respect, 13 variables were explored as controlling factors to wind erosion, and eight of them (e.g., wind speed, topsoil carbon content, topsoil clay content, elevation, topsoil gravel fragment, precipitation, topsoil sand content and soil moisture) were selected as important factors via the Harris Hawk Optimization (HHO) feature selection algorithm. The four models were applied to map land susceptibility to wind erosion, and their performance was assessed by three measures consisting of area under of receiver operating characteristic (AUROC) curve, cumulative gain and Kolmogorov Smirnov (KS) statistic plots. The results revealed that GRU-AL model was considered as the most accurate, revealing that 38.5%, 12.6%, 10.3%, 12.5% and 26.1% of the global lands are grouped at very low, low, moderate, high and very high susceptibility classes to wind erosion hazard, respectively. Interpretation techniques were applied to interpret the contribution and impact of the eight input variables on the model's output. Synergy plot revealed that the soil carbon content exhibited high synergy with DEM and soil moisture on the model's predictions. ALE plot showed that soil carbon content and precipitation had negative feedback on the prediction of land susceptibility to wind erosion. Based on SHAP decision plot, soil moisture and DEM presented the highest contribution on the model's output. Results highlighted new regions at high latitudes (southern Greenland coast, hotspots in Alaska and Siberia), which exhibited high and very high land susceptibility to wind erosion. [ABSTRACT FROM AUTHOR]

In rivers worldwide, multiple scales of dunes coexist. It is unknown how the larger, primary dunes interact with secondary bedforms that are superimposed. We test the hypothesis that streamwise variability in the sediment flux inferred from the downstream migration of secondary bedforms explains migration of the host dune, based on bathymetric data from a lowland, sand‐bedded river. Results indicate that transport estimated from secondary bedform migration increases along the host dune stoss, eroding the stoss slope. When the superimposed bedforms disintegrate at the primary lee slopes, results indicate that all sediment transport associated to secondary bedform migration is arrested in the lee of the host dune, explaining migration of the host dune. When secondary dunes persist however, only part of the sediments transport linked to secondary dunes contributes to the migration of the host dune. This study gives novel insight into the fundamental mechanisms controlling the kinematics of compound dunes. Plain Language Summary: Dunes are undulating features that can develop on a sandy river bed. They migrate downstream as a result of sediments moving from the stoss, the upstream facing slope of the dune, to the lee, the downstream slope of the dune. Sometimes, multiple scales of dunes coexist, where trains of small dunes travel over larger dunes. In this study we investigate how two dune scales interact and how they contribute to the downstream transport of bed sediments. This is done based on a series of field campaigns in the River Waal. The results indicate that migrating secondary dunes contribute to the displacement of the host dune, the dune over which they migrating. In some cases, secondary dunes travel over the host dune stoss and disintegrate at the host dune lee, depositing sediment there. In other cases, secondary dunes travel over the full length of the host dune toward the next, downstream dune. In this case, part of the sediments transport linked to the secondary dunes contributes to the downstream displacement of the host dune, and part of the sediments are transported to the next primary dune. Key Points: Secondary bedforms are omnipresent and are key to understanding primary dune behaviorSediment transport rates linked to migration of superimposed river bedforms increase over the host dune stoss and decrease over the lee sideSecondary bedforms control migration of the host dune, both when they persist over the host dune and when they disintegrate at the lee side [ABSTRACT FROM AUTHOR]

River bedforms and their deposits—fluvial cross strata— respond to floods. However, it is unclear if all floods are equally represented in cross strata. Here, using a series of physical experiments in which bedforms were subjected to equivalent flood magnitudes over varying durations, we demonstrate the existence of a lower bound on flood durations that are represented in cross strata. We show that the scour depths and preserved set thickness are indistinguishable from baseflow conditions when the rising‐limb duration of floods is shorter than the baseflow‐equilibrated bedform turnover timescale—time required to displace the volume of a single bedform at baseflow conditions. In contrast, scour depth and preserved set thickness distributions deviate from baseflow conditions when flood rising‐limb duration exceeds the baseflow‐equilibrated bedform turnover timescale, causing preferential preservation of falling‐limb bedform dynamics. Our work provides a previously unrecognized quantitative bound on flood durations that are represented in fluvial cross strata. Plain Language Summary: Bedforms are routinely found on sandy riverbeds and their deposits, called fluvial cross strata, are the fundamental building blocks of river deposits. It has long been hypothesized that bedforms respond to floods by changing their shape and speed. In addition, fluvial cross strata are hypothesized to record past floods, thus, providing a key window into past hydrologic variability. However, it is unclear if floods of all durations are equally likely to be represented in bedform morphology and fluvial cross strata. Here, we investigate how floods of different durations are recorded in fluvial cross strata using four physical experiments of bedform evolution. We examine changes in bedform morphology (height, length, speed) and preservation with floods of equal magnitude but varying durations and compare the results with a control experiment with steady water and sediment discharge. Our results reveal a previously unrecognized lower limit on preserved flood duration in cross strata, corresponding to the time required to move a single bedform one wavelength (turnover timescale) in baseflow conditions. Only floods with durations longer than the turnover timescale led to identifiable changes in bedform morphology and fluvial cross strata. These findings advance our ability to better interpret geological records of past floods. Key Points: Experiments show that baseflow‐equilibrated bedform turnover timescale sets the lower bound on preserved flood duration in cross strataFloods with a duration less than this lower bound do not cause a detectable change in preserved set thickness and scour‐depth distributionFloods with duration longer than the lower bound cause scour‐depth deepening and preferential preservation of falling‐limb deposits [ABSTRACT FROM AUTHOR]

Aeolian concentration of iron-titanium oxides (black sand) is a common phenomenon on coasts around the world but associated aeolian detrital gold is relatively rare. In contrast, Holocene and active dunes at Waipapa beach on the coast of the southern South Island of New Zealand host aeolian black sand layers with locally abundant finely particulate (<200 µm) gold and platinum, some of which have been mined historically. Aeolian concentration of black sand, gold and platinum is driven by strong prevailing westerly winds (gusts >100 km/h) on annual or decadal time scales. Holocene fluvial recycling of aeolian sands has been important in upgrading the black sand, gold, and platinum contents. Surf concentration of black sand on the beach is minor and merely feeds the aeolian system, and this differs from other beach gold deposits around the world, which are surf-dominated. Most of the Waipapa beach gold (>90%) has flaky morphology with abundant superficial transport-related deformation reflective of fluvial transport, probably down the nearby Mataura River (∼200 km transport) between Miocene and Holocene. Minor distinctive wind-sculpted toroidal gold, and the platinum, arrived from the west (∼300 km transport) via the Waiau River and Foveaux Strait. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive three-dimensional numerical investigation of horizontal square anchors embedded in geogrid-reinforced sand. Prior experimental studies have demonstrated notable enhancements in anchor uplift capacity when placed below geogrid reinforcement in soil. However, these results are limited to small anchor plates tested in laboratory conditions with over-reinforced sand. In contrast, this study focuses on large field-scale anchors and explores the influence of anchor width, embedment depth, reinforcement size, stiffness, and tensile strength on uplift capacity. The findings reveal that the optimal size for geogrid reinforcement is three times the anchor width. A diminishing improvement in uplift capacity with increasing anchor width was observed. Additionally, deeper anchor embedment reduces the uplift capacity improvement in geogrid-reinforced sand. The geogrid reinforcement is found to be more efficient in the case of shallow anchors placed in loose sand. The major contribution of this paper lies in the response analysis of large anchors and providing a better understanding of the uplift mechanism in geogrid-reinforced sand. • This paper presents a three-dimensional numerical investigation of large field-scale horizontal square anchors embedded in geogrid-reinforced sand. • The findings reveal that the optimal size for geogrid reinforcement is three times the anchor width (B) in contrary to the 5B value reported in the previous literature. • A diminishing improvement in uplift capacity with increasing anchor width was observed. • Deeper anchor embedment reduced the uplift capacity improvement in geogrid-reinforced sand. • The geogrid reinforcement is found to be more efficient in the case of shallow anchors. [ABSTRACT FROM AUTHOR]

To enhance the mechanical properties and stability of desert railway embankments, the utilization of geogrids has proven to be an effective measure. The article conducted field tests and discrete element simulations to thoroughly examine the static performance of embankments reinforced with geogrids. The study systematically explored the macroscopic and microscopic characteristics of the geogrid-reinforced embankment under static loading. Various factors were investigated, including the horizontal laying arrangements and depth to the top layer of the geogrid, as well as key design parameters such as the number of geogrid layers, geogrid width, and vertical spacing between geogrid layers. The findings indicate a progressive enhancement in the ultimate bearing capacity of the embankment with an increase in both the number of geogrid layers and the geogrid width. Conversely, there is a decrease in ultimate bearing capacity as the depth to the top layer increases. In comparison to unreinforced embankments, reinforced embankments exhibit a reduced contact anisotropy, signifying that the geogrid effectively disperses static loads, resulting in a more uniform contact distribution. The geogrid restrains both displacement and rotation of the aeolian sand, and this restraining effect progressively strengthens with an increase in the number of geogrid layers or the geogrid width. The research findings can serve as a reference for the design and application of aeolian sand railway embankments. • We conducted triaxial tests on aeolian sand, single rib strip tests on geogrids, and field tests of geogrids reinforced aeolian sand embankments. • Additionally, we developed a two-dimensional discrete element embankment model to investigate the impact of geogrid parameters on the macro and micro performance of reinforced embankments. [ABSTRACT FROM AUTHOR]

Sand rice (Agriophyllum squarrosum), widely distributed in Central Arid Asia and prevalent in the sand dunes of northern China, presents a promising potential as a climate‐resilient crop. The plasticity of hypocotyl growth is the key trait for sand rice to cope with wind erosion and sand burial, ensure seedling emergence, and determine plant architecture. In this study, we assessed the overall hypocotyl phenotype of six sand rice elite lines, which were collected from different regions of northern China, and selected by our group over past decade through common garden trials. Significant phenotypic variations were observed in thousand‐seed weight (TSW), seedling emergence percentage, hypocotyl length and diameter, and seedling fresh weight among the lines. The elite line Aerxiang (AEX) exhibited excellent agronomic performance with superior and synchronous emergence, and high survival percentage, distinguishing itself as a prime candidate for further large‐scale cultivation. Contrastingly, the lines from the arid regions showed markedly lower performance. Partial Least Squares Path Modeling (PLSPM) was used to assess the impact of seed provenance climate factors, including annual mean temperature (AMT) and annual mean precipitation (AMP), on trait variability among lines. The findings indicate a significant correlation between climate factors and hypocotyl length, highlighting the intricate adaptation of sand rice to local climate. The comprehensive understanding of the mechanisms behind phenotypic variations offers valuable insights for sand rice de novo domestication and innovative germplasm resources, and lays the foundation for ecological restoration in sandy areas. [ABSTRACT FROM AUTHOR]

Dunes are the primary geomorphological type in deserts, and the distribution of dune morphologies is of significant importance for studying regional characteristics, formation mechanisms, and evolutionary processes. Traditional dune morphology classification methods rely on visual interpretation by humans, which is not only time-consuming and inefficient but also subjective in classification judgment. These issues have impeded the intelligent development of dune morphology classification. However, convolutional neural network (CNN) models exhibit robust feature representation capabilities for images and have achieved excellent results in image classification, providing a new method for studying dune morphology classification. Therefore, this paper summarizes five typical dune morphologies in the deserts of western Inner Mongolia, which can be used to define and describe most of the dune types in Chinese deserts. Subsequently, field surveys and the experimental collection of unmanned aerial vehicle (UAV) orthoimages for different dune types were conducted. Five different types of dune morphology datasets were constructed through manual segmentation, automatic rule segmentation, random screening, and data augmentation. Finally, the classification of dune morphologies and the exploration of dataset construction methods were conducted using the VGG16 and VGG19 CNN models. The classification results of dune morphologies were comprehensively analyzed using different evaluation metrics. The experimental results indicate that when the regular segmentation scale of UAV orthoimages is 1024 × 1024 pixels with an overlap of 100 pixels, the classification accuracy, precision, recall, and F1-Score of the VGG16 model reached 97.05%, 96.91%, 96.76%, and 96.82%, respectively. The method for constructing a dune morphology dataset from automatically segmented UAV orthoimages provides a reference value for the study of large-scale dune morphology classification. [ABSTRACT FROM AUTHOR]

Background and aims: Windblown sand movements, i.e., wind denudation and sand burial, pose a strong selective pressure on dune vegetation. Dune plants commonly receive repeated wind denudation or sand burial. Therefore, simultaneously examining the role of sand movement intensity and frequency in shaping dune vegetation is critical for dune biodiversity conservation and ecological restoration. However, studies of this nature are rare. Methods: We studied the integrated effects of sand movement intensity and frequency on the seedling performance of a dominant semi-shrub, Artemisia ordosica, in the Mu Us sandland. We subjected A. ordosica seedlings to a total intensity of 10 cm wind denudation or sand burial treatments conducted once, twice or four times. Key results: We found, given that the total intensity of sand movement remains the same, increasing frequency and decreasing intensity per time largely improved seedling survival. Furthermore, increasing frequency and decreasing intensity per time significantly alleviated the negative effects of wind denudation, although such alleviation effect was not detected for sand burial. Seedlings of A. ordosica increased specific leaf area, root length, and biomass allocation to root to adapt to wind denudation, while they developed adventitious roots to adapt to sand burial. Conclusions: Our results demonstrate that a single heavy sand movement is more detrimental than multiple light ones to the performance of A. ordosica seedlings. Our findings suggest that windproof measures to prevent severe sand movements is necessary to allow the establishment of A. ordosica during the dune restoration process. [ABSTRACT FROM AUTHOR]

Gypsum is a common mineral at Gale crater on Mars, currently being explored by the Mars Science Laboratory (MSL) rover, Curiosity. In this paper, we summarize the associations of gypsum with other sulfate minerals (bassanite, anhydrite, jarosite, starkeyite, and kieserite) from the lowest levels of the crater's northern moat zone (Aeolis Palus) up through ~0.8 km of the stratigraphic section in the lower slopes of the sedimentary mound developed around the central peak, Aeolis Mons (informally, Mount Sharp). The analysis is based on results from the CheMin X-ray diffraction instrument on Curiosity, supplemented with information from the rover's versatile instrument suite. Gypsum does not occur with the same frequency as less hydrous Ca-sulfates, likely, in most cases, because of its dehydration to bassanite and possibly to anhydrite. All three of these Ca-sulfate phases often occur together and, along with other sulfates, in mixed assemblages that are evidence of limited equilibration on a cold, dry planet. In almost all samples, at least one of the Ca-sulfate minerals is present, except for a very limited interval where jarosite is the major sulfate mineral, with the implication of more acidic groundwater at a much later time in Gale crater's history. Although observations from orbit reveal a sulfate-rich surface, currently active dark basaltic dunes at Gale crater have only small amounts of a single sulfate mineral, anhydrite. Gale crater has provided the most complete mineralogical analysis of a site on Mars so far, but the data in hand show that Gale crater mineralogy is not a blueprint with planet-wide application. The concurrent study of Jezero crater by the Mars 2020 mission and comparisons to what is believed to be the most extensive deposit of gypsum on Mars, in the dune fields at the north polar ice cap, show significant diversity. Unraveling the stories of gypsum and other sulfates on Mars is just beginning. [ABSTRACT FROM AUTHOR]

Tamarix ramosissima has an important role in stabilizing sand dunes in desert ecosystems. Understanding the water use strategies of T. ramosissima is essential to understand its adaptations on coppice dunes. We utilized the stable isotopes δ2H and δ18O in soil water, groundwater, and xylem water to identify monthly differences in water sources. Additionally. we explored rooting depth using 2H2O as an artificial tracer. In May, T. ramosissima derived 75% of its water from shallow and middle soil layers. In July, it absorbed 90% water from middle and deep soil layers. In August and September, it acquired approximately 80% of its water from deep soil layers. The labelling using 2H as an artificial tracer indicated that the root system of T. ramosissima could reach depths >500 cm in the coppice dunes. 2H absorption was observed at depths of 100, 200, 300 and 400 cm. Soil water is the dominant water source for T. ramosissima in the coppice dunes because groundwater is at depths >30 m. The flexible water‐use strategies of T. ramosissima enable it to effectively utilize different available water sources to adapt to the arid environment. These findings improve our understanding of water uptake patterns and drought adaptation strategies of T. ramosissima in the coppice dunes of desert ecosystems. [ABSTRACT FROM AUTHOR]

Coastal areas are among the planet's most dynamic yet vulnerable environments, the shape of sand dunes being typically modeled by two sets of forces: the relatively constant action of wind and waves and the disturbances caused by infrequent but powerful storms. These meteorological events affect the plant communities, but can also play an important role in the long-distance dispersal of some psammophytes. Plants can be exposed, uprooted, broke apart and spread by wind and waves. Then, depending on the resilience of the plant to seawater temperature, the duration of immersion, the type of fragment transported and the suitability of the new habitat, new population can be established. This study aimed to assess the resilience to seawater immersion and the ability of long-distance dispersal of three psammophytes: Convolvulus persicus, Alyssum borzaeanum, and Silene thymifolia. The experiments tested the viability of vegetative fragments and the reproductive capacity of seeds under different exposure periods (5, 10, and 15 days) and temperature conditions: 4 °C (average surface seawater temperature during winter and early spring when storms on the Black Sea Coast occur), 13 °C (average surface seawater temperature), and 23 °C (average summer surface seawater temperature). The increase of both seawater temperature and the exposure time had a significant negative influence on the viability of the vegetative fragments and on germination capacity. After exposure to seawater, Convolvulus persicus, and Silene thymifolia are able to establish new populations through vegetative fragments or seeds, whilst in case of Alyssum borzaeanum, no vegetative regeneration was observed. [ABSTRACT FROM AUTHOR]

This work compares two dune fixation processes in Catalonia (Spain), the Montgrí and Begur massifs and the Llobregat delta, and disproves that both were undertaken to impede the advance of the sands. The fixation process in the Montgrí and Begur massifs is well documented and was planned in response to the need to stop sand advancement, whereas in the case of the Llobregat delta, the actions taken were spontaneous, took place over centuries and were aimed at mitigating health issues while at the same time gaining an economic benefit from the fruit and wood of the planted pine trees. [ABSTRACT FROM AUTHOR]

The article "Historical Studies of the Landscape" presents different approaches and methods for studying the relationship between landscape and history. It highlights the importance of understanding past and current landscapes, as well as the interaction between the environment and the societies that inhabit them. The article also mentions several specific studies that focus on different regions, such as Central America, Central Europe, and Spain. These studies analyze the evolution of plant landscapes, changes in land use, coastal dune fixation, and the impact of transhumance on the landscapes of Gran Canaria. Overall, the article emphasizes the importance of adopting an integrated and multidisciplinary approach to understanding historical landscapes. [Extracted from the article]

The maintenance of biological diversity is frequently enhanced in a heterogenous landscape by some level of disturbance. Thus, when a landscape becomes stabilized and homogenized through the spread of an invasive plant species, there may be consequences for native biodiversity, particularly for those biotas that depend on the pre‐existing, natural disturbance regime of that landscape. At Long Point, Ontario, Canada, a sandspit in Lake Erie, the community of anuran amphibians experienced the co‐incidence of 2 major disturbance events, 1 anthropogenic and 1 natural: an intervention to remove the invasive form of the common reed (Phragmites australis australis) and a spate of extensive dune washouts caused by high water levels and storms. As a result of the unequal distribution of disturbance in the landscape, different areas were affected by only the dune washouts, only the common reed treatment, both disturbances, or neither disturbance. From May to August 2021, we explored how the disturbances affected the resident frog and toad species habitat associations in the 4 different disturbance conditions in the landscape. By means of minnow traps, acoustic surveys, and visual surveys, we determined that the dune washouts had a greater influence on resident anurans than the common reed treatment. Ranid frogs (Ranidae) tended to inhabit non‐washout sites, whereas Fowler's toads (Anaxyrus fowleri) congregated in the newly formed, sand flats and shallow, de‐vegetated pools resulting from the washouts. Neither ranid frogs nor Fowler's toads demonstrated avoidance of the sites affected by the herbicide treatment and mechanical rollover of the common reed. This evidence of species sorting, which enables multiple species to persist in a dynamic and heterogeneous landscape, suggests that wildlife management in aid of threatened species recovery may find success by encouraging natural disturbance regimes in dynamic landscapes. Future management endeavors should consider refraining from complete dune stabilization in these landscapes to allow the natural washouts to occur at a higher frequency, while ensuring the continued effectiveness of the invasive common reed eradication. [ABSTRACT FROM AUTHOR]

Habitat destruction and fragmentation are one of the main drivers of pollinator decline and biodiversity loss in general. However, the exact effects of habitat fragmentation on pollinator communities are still poorly understood, and it remains unclear which patch characteristics are most important in driving pollinator diversity and community composition.In this study, we inventoried plant and insect diversity in a total of 19 fragmented dune slacks in Belgium. Specifically, we assessed the effects of dune slack area and connectivity on plant and pollinator diversity and community composition. Additionally, we investigated to what extent plant diversity had an impact on insect pollinator communities.The results indicated that species richness of both plants and insects was significantly related to patch area, whereas patch connectivity only had a significant effect on plant diversity. Nestedness analyses showed that plant communities of small dune slacks were a subset of the communities of large patches, but no such patterns were found for insect communities. Turnover in pollinator communities was high and significantly related to the distance separating dune slacks.Overall, our results highlight the importance of large patches for sustaining both plant and pollinator communities. Additionally, enhancing connectivity has the potential to promote plant diversity and consequently benefit pollinator species. [ABSTRACT FROM AUTHOR]

In this study, centrifuge model tests were carried out to investigate the lateral response of single pile in coral sand foundation. The load–displacement relationships, pile deflections, bending moments, the changes in horizontal soil pressure, the predicted particle crushing behaviors, and p-y curves were compared and discussed in detail to study the influence of pile diameter and vertical load. Test results show that increasing diameter is the most direct and effective method to improve the horizontal bearing capacity of pile; the presence of vertical load would lead to an increase of bending moment and lateral displacement of the pile due to P-Δ effect and an improvement in soil resistance due to the vertical compression effect; the influence of particle breakage behavior of coral sand was not significant. In addition, the applicability of the existing p-y models for the coral sand foundation was systematically evaluated. According to the comprehensive analysis of the stress state of sand around pile, the evolution of soil resistance with depth was determined, which can be simulated by a power function. Based on the centrifuge test results, a modified p-y model for coral sand was proposed, and its rationality and applicability in predicting pile–soil responses were validated systematically. [ABSTRACT FROM AUTHOR]

The article explores the Spring Warrior civic-ceremonial center on Florida's Gulf Coast, which is one of the earliest centers of its kind in eastern North America. The site has recently been investigated, revealing evidence of village occupation, changes in subsistence, and a unique architectural feature using oyster shells for structural support. The findings highlight the significance of the Spring Warrior Complex in the ancient social landscape and ongoing research aims to nominate it for the National Register of Historic Places. The article provides insights into the origins and persistence of residential villages among hunter-gatherer-fishers in eastern North America, with unique local distinctions influenced by sociocultural, environmental, and climatic factors. [Extracted from the article]

In this study, the impacts to soil thermal properties during and after biocementation via microbially induced calcite precipitation (MICP) method on silty silica sand specimens with varying fines content (0%, 5%, and 15%) were investigated. Firstly, calcium conversion was measured after each pulse; then, the MICP-treated specimens were tested for cementation uniformity. The evolution of thermal conductivity of silty soils with the MICP treatment was assessed using a thermocouple probe. The results show that thermal conductivity of silty saturated sands increased by 17% for specimens treated to 9.7% CaCO3. The improvement in thermal conductivity was attributed to the formation of calcium carbonate bridges binding the soil grains together. The results suggested that the thermal conductivity of silty soil depends on water content, the number of treatment pulses, and the treatment uniformity through the soil specimen. Presence of fines content in the soil was found to play an important role in the distribution and uniformity of biocementation through the soil specimen. However, no statistically significant difference in the thermal conductivity values of MICP-treated specimens with different fines content was observed (p>0.05). The average calcium carbonate content ranged between 10.7% and 7.2% for the soils with 0% and 15% fines content, respectively. The findings of this research could be used to improve the efficiency of geothermal boreholes and other energy geostructures using MICP by improving thermal conductivity of dry and partially saturated soil. [ABSTRACT FROM AUTHOR]