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Sand nourishments and groynes as coastal protection measures (CPM) address similar challenges on sandy coasts but take different approaches: while groynes are intended to reduce alongshore sediment transport and erosion, nourishments add new sediment to the system to compensate for erosion. The aim of this study is to compare the ecological effects of such measures on the vegetation. To this end, nutrient analysis and botanical mappings were carried out on a site with installed groynes, a site where sand nourishments are regularly carried out, and a control site without any CPM. In addition to an increase in nutrient availability after the sand nourishment, significant changes in plant species diversity and composition were also measured. The number of higher plants, mosses, and lichen species was lower at the nourishment site. The opposite impacts were observed at the groyne site: an increase in sediment cover by higher plants and mosses and a distinct increase in lichen species. The results suggest that groynes lead to a stabilization of the coastal system and enable dense vegetation growth. In contrast, sand nourishments lead to nutrient input and unstable habitat conditions, attracting certain plant communities but preventing the establishment of ground-covering vegetation.

Sand nourishments and groynes as coastal protection measures (CPM) address similar challenges on sandy coasts but take different approaches: while groynes are intended to reduce alongshore sediment transport and erosion, nourishments add new sediment to the system to compensate for erosion. The aim of this study is to compare the ecological effects of such measures on the vegetation. To this end, nutrient analysis and botanical mappings were carried out on a site with installed groynes, a site where sand nourishments are regularly carried out, and a control site without any CPM. In addition to an increase in nutrient availability after the sand nourishment, significant changes in plant species diversity and composition were also measured. The number of higher plants, mosses, and lichen species was lower at the nourishment site. The opposite impacts were observed at the groyne site: an increase in sediment cover by higher plants and mosses and a distinct increase in lichen species. The results suggest that groynes lead to a stabilization of the coastal system and enable dense vegetation growth. In contrast, sand nourishments lead to nutrient input and unstable habitat conditions, attracting certain plant communities but preventing the establishment of ground-covering vegetation. [ABSTRACT FROM AUTHOR]

Hurricanes Ian and Nicole caused devastating destruction across Florida in September and November 2022, leaving widespread damage in their wakes. This study focuses on the assessment of barrier islands' shorelines, encompassing natural sand dunes and dune vegetation as well as armored dunes with man-made infrastructure such as seawalls. High-resolution satellite imagery from Planet was used to assess the impacts of these hurricanes on the beach shorelines of Volusia, Flagler, and St. Johns Counties on the Florida Central East Coast. Shorefront vegetation was classified into two classes. Normalized Difference Vegetation Index (NDVI) values were calculated before the hurricanes, one month after Hurricane Ian, one month after Hurricane Nicole, and one-year post landfall. LiDAR (Light Detection and Ranging) was incorporated to calculate vertical changes in the shorelines before and after the hurricanes. The results suggest that natural sand dunes were more resilient as they experienced less impact to vegetation and elevation and more substantial recovery than armored dunes. Moreover, the close timeframe of the storm events suggests a compound effect on the weakened dune systems. This study highlights the importance of understanding natural dune resilience to facilitate future adaptive management efforts because armored dunes may have long-term detrimental effects on hurricane-prone barrier islands. [ABSTRACT FROM AUTHOR]

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Coastal dune distinction is an essential for monitoring, conservation and sustainable management of fragile coastal ecosystem. Most of the coastal scientists classified the coastal sand dunes by conventional methods as frontal dunes (foredune) and back dunes (stabilized dune). Due to the significance in the developing stage of the dunes and the coastal protection, foredunes are very significant in this context. Studies demarcating the boundary of coastal dune field based on its spectral signatures of vegetation species have not been attempted by any authors earlier. In this view, the goal of this study was to determine whether it is possible to demarcate the foredune from the dune field using vegetation species with the aid of Airborne Visible InfraRed Imaging Spectrometer—Next Generation (AVIRIS-NG) hyperspectral data. To achieve this, the study scrutinized the major vegetation species and the end members were identified using Pixel Purity Index algorithm (PPI), N-Dimensional visualizer, Insitu spectra and Linear Spectral Unmixing algorithm. Identified training pixels falling in the dune field were grouped into six training classes to perform classification techniques (Spectral Angle Mapper (SAM), Spectral Informative Divergence (SID) and Support Vector Machine (SVM)). This study also discussed about various methods of selecting training pixels for demarcation of foredunes. Accuracy assessment reveals that SVM shows an overall accuracy of 91.97% compared to SID of 68.25% and SAM of 58.52% with kappa coefficient of 0.89, 0.53 and 0.49 respectively. The study found the indicator species such as Ipomoea Pes-caprae, Spinifex Littoreus and Launaea Sarmentosa blankets the foredunes in this study area, which could be used to demarcate the boundary of the foredunes. The methodology employed in this study can be applied to distinguish the foredune from the dune field in any coastal dune ecosystem, provided that the researcher has access to a database of the flora present in the area. The proposed methodology and this research might bring new insight into the classification and demarcation of foredune using the vegetation species present over the dune field. The research allows more efficient and cost-effective identification of foredunes from vast coastal environments, providing valuable information for the conservation and sustainable management of ecologically sensitive ecosystems. [ABSTRACT FROM AUTHOR]

In recent years, there has been increasing societal awareness of the crucial role that coastal dunes play in protecting against rising sea levels, mitigating climate change impacts, promoting biodiversity, and providing recreational opportunities. In some regions, dune management has been particularly focused on biodiversity and ecosystem restoration and the presence of alien species on dunes raises concerns about how these species become 'native,' 'invasive,' or 'hybrids' and whether they belong in their new ecosystems. These concerns illustrate how certain animals and plants assume different statuses according to normative categories associated with varying objectives. This article explores how perceptions of coastal dunes in the UK have transformed over time, from marginal resource frontiers to highly valued environments shaped by multispecies relations. In addition, this work explores how dunes around the UK emerge as 'patchy anthropocoasts,' that is, uneven landscapes designed by human purposes linked to economic activities, conservation, rabbit populations, unwanted vegetation, and the control of unpredictable sand movements. Bringing together diverse historical materials and scientific literature, this article links human and nonhuman histories with present debates on dune restoration from a transdisciplinary perspective rooted in anthropology, environmental history, and the natural sciences. [ABSTRACT FROM AUTHOR]

Shiflett, S.A. and Backstrom, J.T., 2023. Impacts of Hurricane Isaias (2020) on geomorphology and vegetation communities of natural and planted dunes in North Carolina. Journal of Coastal Research, 39(4), 587–609. Charlotte (North Carolina), ISSN 0749-0208. Coastal dunes serve a crucial role in reducing inland flooding, slowing shoreline erosion, and acting as a physical barrier to protect developed coastal communities from storm-related impacts. Dunes also provide critical habitat for several shoreline species. High magnitude storms such as hurricanes and nor'easters can have profound and long-lasting impacts on low-lying coastal areas, ranging from minor and temporary beach erosion to complete devastation of entire barrier island systems. This study documents direct impacts of Category 1 Hurricane Isaias (2020), one of the strongest tropical storms to directly hit the region, on coastal dune geomorphology and vegetation of Holden Beach, a south-facing barrier island located in SE North Carolina. Impacts were investigated using a combination of pre- and poststorm real-time kinematic dune profiles, vegetation cover and type transects, prestorm high-resolution drone imagery, and poststorm National Oceanic and Atmospheric Administration aerial imagery. Dominant geomorphological impacts included a variety of depositional and erosional effects, which were more prominent along artificially renourished and planted coastal segments compared to adjacent natural dune systems. Geomorphological changes subsequently reduced poststorm dune vegetation density. Yet, reduced impact on vegetation species abundance (i.e. stem density) was evident at a wider, stabilized dune area, which lacked human management, compared with narrower, less mature, and actively managed (i.e. fenced and/or planted) dune areas. Dune grasses were more resilient to Hurricane Isaias than forbs; however, several volunteer forb species, noted for dune stabilization abilities, were present at unmanaged dunes. Results indicate planting a diverse palette of native coastal species, which when co-occurring fill a variety of functional roles, will increase dune resilience to tropical storms. This study provides important insights into optimizing dune management strategies for developed barrier islands and other low-lying temperate coastal regions, which may be susceptible to ongoing sea-level rise and high-energy storm events. [ABSTRACT FROM AUTHOR]

Understanding the dynamics of beach–dune systems is crucial for effective coastal management. The cellular automata model DuBeVeg provides a powerful tool for simulating and understanding the bio-geomorphological evolution of these systems, capturing key interactions of aeolian, hydro-, and vegetation dynamics in a simplified manner. In this study, we present an alternative representation of the aeolian transport component in DuBeVeg, aiming to better capture the saltation transport mode that prevails on beaches. This new representation is compared with the original aeolian transport representation in DuBeVeg, which is inspired by ripple migration. For three beach width scenarios, we considered the effects of the different aeolian transport representations on the predicted foredune morphology after 50 years, as well as the spatio-temporal evolution of the beach–dune system leading to that morphologic state. The saltation transport representation resulted in a more realistic simulation of the seaward expansion of the foredune compared with the original representation, particularly in scenarios with wide and prograding beaches. The new representation also more accurately captured the amplitude of aeolian bedforms emerging across the beach. These findings highlight the importance of selecting the representative transport mode when simulating the transient bio-geomorphological evolution of beach–dune systems. [ABSTRACT FROM AUTHOR]

The establishment of large populations of yellow-legged gull Larus michahellis in coastal and urban areas can lead to strong changes in vegetation cover and composition through creating physical disturbance in the vegetation and impacting the soil quality through defecation. In this study, we evaluated the effects of breeding yellow-legged gull populations on tall and short vegetation cover and plant species composition in old (occupied for 13 years) and new (occupied for 3 years) colony sites in grey dunes of the Algarve, southern Portugal. In each site, sampling plots were used to measure the percentage of vegetation cover in areas with and without breeding gulls. In the old colony site, the cover by tall vegetation was substantially reduced and the cover by short vegetation substantially increased in the areas where gulls are breeding in comparison with the adjacent areas. In the new colony sites, there were only minor differences. The increase in cover of short vegetation in the breeding area of the old colony site was mostly by nitrophilous species (Paronychia argentea and Malcolmia littorea) and should be explained by the decrease in vegetation cover of tall plant species and by feces deposition. Tall and slow-growing species Suaeda maritima and Helichrysum italicum covers were negatively affected. Our results showed that yellow-legged gulls affected vegetation cover and composition of grey dunes after 3 years of consecutive breeding, and this should be considered in the management of these habitats where breeding yellow-legged gulls are increasing. [ABSTRACT FROM AUTHOR]

Understanding the dynamics of beach–dune systems is crucial for effective coastal management. The cellular automata model DuBeVeg provides a powerful tool for simulating and understanding the bio-geomorphological evolution of these systems, capturing key interactions of aeolian, hydro-, and vegetation dynamics in a simplified manner. In this study, we present an alternative representation of the aeolian transport component in DuBeVeg, aiming to better capture the saltation transport mode that prevails on beaches. This new representation is compared with the original aeolian transport representation in DuBeVeg, which is inspired by ripple migration. For three beach width scenarios, we considered the effects of the different aeolian transport representations on the predicted foredune morphology after 50 years, as well as the spatio-temporal evolution of the beach–dune system leading to that morphologic state. The saltation transport representation resulted in a more realistic simulation of the seaward expansion of the foredune compared with the original representation, particularly in scenarios with wide and prograding beaches. The new representation also more accurately captured the amplitude of aeolian bedforms emerging across the beach. These findings highlight the importance of selecting the representative transport mode when simulating the transient bio-geomorphological evolution of beach–dune systems.

The formation and evolution of coastal dunes result from a complex interplay of eco-morphodynamic processes. State-of-the-art models can simulate aeolian transports and morphological dune evolution under certain conditions. However, a model combining these processes for coastal engineering applications was not yet available. This study aims to develop a predictive tool for dune development to inform coastal management decisions and interventions. The aeolian sediment transport model AeoLiS is extended with functionalities that allow for simulations of coastal landforms. The added functionalities include the effect of topographic steering on wind shear, avalanching of steep slopes and vegetation processes in the form of growth and wind shear reduction. The model is validated by simulating four distinct coastal landforms; barchan-, parabolic-, embryo dunes and blowouts. Simulations, based on real-world conditions, replicate the landform formation, migration rates and seasonal variability. • Dune shaping processes are implemented into AeoLiS enabling landform simulations. • Four distinct landform types are simulated utilizing AeoLiS. • AeoLiS replicates accurate landform shapes and dynamics under real-world conditions. • Capabilities added to AeoLiS enable its use for a range of engineering applications. [ABSTRACT FROM AUTHOR]

The establishment of large populations of yellow-legged gull Larus michahellis in coastal and urban areas can lead to strong changes in vegetation cover and composition through creating physical disturbance in the vegetation and impacting the soil quality through defecation. In this study, we evaluated the effects of breeding yellow-legged gull populations on tall and short vegetation cover and plant species composition in old (occupied for 13 years) and new (occupied for 3 years) colony sites in grey dunes of the Algarve, southern Portugal. In each site, sampling plots were used to measure the percentage of vegetation cover in areas with and without breeding gulls. In the old colony site, the cover by tall vegetation was substantially reduced and the cover by short vegetation substantially increased in the areas where gulls are breeding in comparison with the adjacent areas. In the new colony sites, there were only minor differences. The increase in cover of short vegetation in the breeding area of the old colony site was mostly by nitrophilous species (Paronychia argentea and Malcolmia littorea) and should be explained by the decrease in vegetation cover of tall plant species and by feces deposition. Tall and slow-growing species Suaeda maritima and Helichrysum italicum covers were negatively affected. Our results showed that yellow-legged gulls affected vegetation cover and composition of grey dunes after 3 years of consecutive breeding, and this should be considered in the management of these habitats where breeding yellow-legged gulls are increasing.

The alongshore response of dunes to storm events can be extremely variable and, consequently, their capacity to maintain their services, including the protection of hinterland communities. In this study, the role of biotic and abiotic factors determining the magnitude of dune retreat driven by a severe storm along a 60 km barrier island system was investigated. Data from high‐resolution satellite imagery, digital terrain models, and wave propagation models were used in this assessment. The assessed abiotic factors included the backshore volume, dune height, downdrift inlet distance, and incident wave power. The evaluated biotic factor was the vegetation cover, characterized by a vegetation index retrieved from the multispectral imagery. The results revealed large alongshore variability on dune retreat, ranging from negligible impact to ca. 40 m of retreat. All combined factors allowed us to explain up to 70% of the dune retreat variability through a multi‐regression analysis. Among all investigated factors, the major contributor controlling the magnitude of dune retreat was the backshore volume (more robust berms reduced the retreat) followed by the wave power (normal and longitudinal components). Moreover, the removal of local salient features in the dune line caused the straightening of the coastline, highly contributing to the development of dune retreat hotspots. The other evaluated factors had a smaller influence on reducing coastal retreat, including the vegetation, whose contribution to dune protection was around one order of magnitude lower than that provided by the backshore volume. The results highlight the importance of regional assessments to understand the causes behind the large alongshore variability of storm impacts at dunes. They also state the relatively low influence of the vegetation from this climatic region to enhance dune resistance to storms. [ABSTRACT FROM AUTHOR]

Several regulatory and management tools are commonly used to prevent negative effects of human trampling on sand dune habitats, but few studies have attempted to evaluate the effects of boardwalks on dune vegetation. We aimed to evaluate changes of species richness and cover, floristic composition and ecological functional guilds among different dune habitats 2 years after the boardwalks had been established, highlighting those habitats mainly affected by these changes. In a Special Protection Area of Molise region (Italy), we sampled 53 square plots before the installation of five wooden boardwalks (control plots) and 57 plots after the boardwalks had been set up (testing plot), across the whole dune system ranging from the upper beach to the pine forest. We compared species richness through rarefaction curves, considering two plant functional groups: focal species (characteristic and diagnostic) and ruderal/exotic species. We finally compared florist composition and cover changes between time intervals, dune habitats and functional groups. In all habitats the total plant richness of testing plots was higher than in the control plots. In beach and mobile dunes habitat focal species drive the increase in both species’ richness and cover. Dune grasslands proved to be the most affected by the presence of ruderal and exotic species, while the more stable fixed dunes habitat was less affected by species changes. Only 2 years after the boardwalks having been set up, we have found a rapid recovery since human trampling was limited. The use of boardwalks could be an effective tool for reducing negative impact of bathing tourism on coastal dunes and requires little and inexpensive maintenance. [ABSTRACT FROM AUTHOR]

Aim: The EUNIS Habitat Classification is a widely used reference framework for European habitat types (habitats), but it lacks formal definitions of individual habitats that would enable their unequivocal identification. Our goal was to develop a tool for assigning vegetation‐plot records to the habitats of the EUNIS system, use it to classify a European vegetation‐plot database, and compile statistically‐derived characteristic species combinations and distribution maps for these habitats. Location: Europe. Methods: We developed the classification expert system EUNIS‐ESy, which contains definitions of individual EUNIS habitats based on their species composition and geographic location. Each habitat was formally defined as a formula in a computer language combining algebraic and set‐theoretic concepts with formal logical operators. We applied this expert system to classify 1,261,373 vegetation plots from the European Vegetation Archive (EVA) and other databases. Then we determined diagnostic, constant and dominant species for each habitat by calculating species‐to‐habitat fidelity and constancy (occurrence frequency) in the classified data set. Finally, we mapped the plot locations for each habitat. Results: Formal definitions were developed for 199 habitats at Level 3 of the EUNIS hierarchy, including 25 coastal, 18 wetland, 55 grassland, 43 shrubland, 46 forest and 12 man‐made habitats. The expert system classified 1,125,121 vegetation plots to these habitat groups and 73,188 to other habitats, while 63,064 plots remained unclassified or were classified to more than one habitat. Data on each habitat were summarized in factsheets containing habitat description, distribution map, corresponding syntaxa and characteristic species combination. Conclusions: EUNIS habitats were characterized for the first time in terms of their species composition and distribution, based on a classification of a European database of vegetation plots using the newly developed electronic expert system EUNIS‐ESy. The data provided and the expert system have considerable potential for future use in European nature conservation planning, monitoring and assessment. [ABSTRACT FROM AUTHOR]

Villate D. A.; Portz L.; Manzolli, R.P., and Alcántara-Carrió J., 2020. Human disturbances of shoreline morphodynamics and dune ecosystem at the Puerto Velero spit (Colombian Caribbean), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No.95, pp. 711-716. Coconut Creek (Florida), ISSN 0749-0208. Evolution of present coastal environments is controlled by both natural processes and anthropogenic activities, last one causing global, regional and local disturbances. This study analyze the effects of shortage of sediments from Magdalena River and tourism development in the recent shoreline morphodynamics and dune vegetation structure of the Puerto Velero spit, in the northern Colombian Caribbean coast. Shoreline position, dune vegetation and human occupation were taken from the interpretation of satellite images, aerial photographs and field trips. Three methods were applied to analyze shoreline migration. It allowed to deduce trends of very high erosion for the outer neck and moderate to high erosion for the inner neck, while the northern border and the point of the spit present an erosional trend in the outer and inner. Therefore, the outer neck and iner neck show predominance of an erosional trend, more intense for the outer one, while the northern border and particularly the point of the spit present trends of high and very high accretion. It implicates a present progradation of the spit, but a narrowing of its neck. The shortage of coastal sand due to the construction of a jettie at Magdalena River favored the formation of the spit by the erosion of the extinct Isla Verde barrier island, but currently cause erosion of the neck. Erosion of the outer and inner neck is also due to the impact of local disturbances on the backshore and dune system, mainly a rapid increase of occupation and a large circulation of people and vehicles. Dune vegetation distribution is affected by these disturbance, including the presence of invasive aloctonous Calotropis procera over a large area of the dune field. The natural climatic oscillations, particularly the negative El Niño Southern Oscillation (ENSO) events, also favor the progradation of the spit. The analysis of these disturbances on the present geomorphological and ecological evolution on the spit constitutes an important instrument for coastal management. [ABSTRACT FROM AUTHOR]

This paper presents and validates a novel root model which accounts for the effect of belowground biomass on dune erosion volumes in XBeach, based on a small-scale wave flume experiment that was translated to a larger scale. A 1D-XBeach model was calibrated by using control runs considering a dune without vegetation. Despite calibration, a general model–data mismatch was observed in terms of overestimated erosion volumes around the waterline. Furthermore, the prediction of overwash had to be induced by increasing the maximum nearshore wave height within the XBeach simulation. Subsequently, applying the root model resulted in a good agreement with the belowground biomass cases, and the consideration of spatially varying rooting depths further improved the results. Predictions of the root model while using locally increased friction coefficients were in line with the aboveground and belowground biomass cases. However, the effect of the root model on the erosion predictions varied among the hydrodynamic conditions, so further improvements are required. Therefore, future research should focus on quantifying the effects of land-based biomass and individual plant characteristics, such as root density, on dune erodibility at large scales, along with their influences on the temporal evolution of dune scarping and avalanching.

The cashew, Anacardium occidentale, is a globally important tropical fruit tree, but little is known about its natural infraspecific systematics. Wild Brazilian populations occur in the cerrado biome and coastal restinga vegetation. We investigated whether wild coastal and domesticated populations could be distinguished genetically using inter-simple repeat molecular markers (ISSRs). In total, 94 polymorphic loci from five primers were used to characterise genetic diversity, structure and differentiation in four wild restinga populations and four domesticated ones from eight localities in Piauí state (30 individuals per population). Genetic diversity was greater overall in wild (%P: 57.2%, I: 0.24, He : 0.15) than domesticated populations (%P: 49.5%, I: 0.19, He : 0.12). Significant structure was observed among the eight populations (between-population variance 22%, ΦPT = 0.217, P ≥ 0.001), but only weak distinctions between wild and domesticated groups. Cluster and principal coordinate analyses showed marked genetic disparity in populations. No correlation of genetic and geographical inter-population distance was found (Mantel test, r = 0.02032, P = 0.4436). Bayesian analysis found an eight-group optimal model (ΔK = 50.2, K = 8), which mostly corresponded to sampled populations. Wild populations show strong genetic heterogeneity within a small geographical area despite probable gene flow between them. Within-population genetic diversity of wild plants varied considerably and was lower where extractive activities by local people are most intense (Labino population). The study underlines the importance of wild populations as in situ genetic reserves and the urgent need for further studies to support their conservation. [ABSTRACT FROM AUTHOR]

Questions: In many places worldwide, dune vegetation has rapidly declined owing to the expansion of various land uses, which pose a serious threat to many native dune plant species. A better understanding of species–area relationships in coastal sandy patches (i.e., beaches and dunes) is valuable for designing effective management strategies for the conservation of beach–dune flora in coastal regions. We investigated how the area and other attributes of sandy patches affect the number of species (dune, inland, and alien species) and whether the occurrence of all dune species is area‐dependent. Location: Sandy coast of San'in Kaigan National Park, western Japan. Methods: All vascular plants at 43 sites (sandy patches) were recorded. Using generalized linear models, we analyzed the relationships of the area and other attributes of sandy patches with the number of species and the relationship between the area of sandy patches and the occurrence (presence/absence) of each dune species. Results: Larger sandy patches maintained a greater number of dune species and harbored some nationally threatened ones. The number of inland and alien species also increased with an increasing area of sandy patches, although the effects of other size and site attributes varied; shoreline length, beach–dune height, and high openness of the beach were selected as important positive factors for the number of dune species. Furthermore, most dune species in herb and dwarf shrub zones were area‐dependent and tended to occur in larger sandy patches, whereas some species of the tidal drift zone, including locally threatened dune species, were area‐independent. Conclusions: Effective conservation of beach–dune flora demands not only the protection of larger sandy patches but also the selective preservation of sandy patches with better developed dunes. Moreover, the maintenance of unstable habitats for area‐independent dune species is important. [ABSTRACT FROM AUTHOR]

Highlights • This research analyzes aeolian processes in an aeolian shadow induced by resorts. • The aeolian shadow is studied locally through wind, vegetation and topography data. • The regional wind direction influences the degree of wind speed change. • The erosive processes are affected by the distance to the resort and the topography. • Where erosive processes are not detected is related to the vegetation role. Abstract Structures and infrastructures can modify aeolian sedimentary dynamics as has occurred in the arid transgressive dunefield of Maspalomas (Gran Canaria, Canary Islands), where an aeolian shadow zone has been formed leeward of a tourist resort (Playa del Inglés). The aim of this paper is to analyse spatial and statistically the influences of vegetation and topography on wind flow across this shadow zone. An experiment was carried out in March 2017, collecting wind speed and direction from 5 transects with anemometers at 0.40 m height. Simultaneously, a drone flight was carried out, from which an orthophoto and digital elevation and surface models (DEM and DSM) were obtained. Distance from the resort, and the presence of vegetation were found to influence transects dominated by erosional processes. Transects that do not display erosional processes were primarily affected by the presence of vegetation. The local wind field changes at a similar distance across the transects downwind from the resorts indicating an acceleration or reattachment of the wind at this distance downwind. The vegetation role in this aeolian shadow zone could be a key to the future evolution of the area resulting in either further stabilization, or alternatively, the continued deflation of the area. [ABSTRACT FROM AUTHOR]

Coastal ecosystems are among the world's most threatened environments, as they undergo diverse anthropogenic pressures, which trigger habitat alteration along with rarefaction and/or local extinction of native species. In this study, we performed a floristic investigation aimed at assessing the environmental status of two protected sandy areas located on the Tyrrhenian coast of southern Italy, the southern Garigliano estuary area and Castel Volturno Nature Reserve. These localities show similar geomorphological and climatic conditions, but different land uses and management practices. The sampling of the vascular plants was carried out through geo-location of species, to allow their availability to national and international floristic mapping projects. At whole territory and habitat types level, major trends for shared and exclusive species composition were identified through the analysis of life form, chorology percentage spectrum and similarity index. We detected that the total vascular flora is composed by 429 species, and found out that Garigliano is slightly richer in species (317) than Castel Volturno (311). It is important to note that Garigliano and Castel Volturno's richness in plants was considerably significant in comparison with other coastal areas of central and southern Italy. Furthermore, although we pointed out that the studied areas showed a low degree of floristic similarity, the shrubland habitat encompassed the highest number of total species and plants of floristic interest (i.e., Italian endemic, rare in Campania, plants included in CITES convention, Habitat Directive, Regional Law of Campania 40/94, National and Regional Red List) in both areas. Finally, despite a severe alteration due to direct anthropogenic disturbance and large-scale alterations that occurred in the last 60 years, we showed that several species of phytogeographical interest are still found in the studied coastal sandy areas, confirming the great importance of this territory for plant diversity and conservation. [ABSTRACT FROM AUTHOR]

Global atmospheric temperatures are predicted to rapidly increase within the next hundred years, consequently altering the microclimates of the sand dune environment where marine turtles lay their eggs. High nest temperatures can increase embryonic mortality, decrease hatchling vigour and size (i.e. quality), and also feminises the sex-ratio of clutches. Sand composition, vegetation cover, rainfall and sun exposure affect the temperature of sand surrounding a nest, however the effect of this variability in the beach environment on the incubation success of a sea turtle clutch is still relatively unknown. We conducted a manipulative study on loggerhead turtle nests at Mon Repos, Queensland, Australia, to investigate the effect of ground-cover vegetation vs bare sand and tree-shade vs no shade on incubation success, hatchling morphology and hatchling locomotor performance. Twenty-four nests were used in a two-factor experimental design, with tree-shade/sun and, ground-cover vegetated/cleared as fixed factors. Sun-exposed nests experienced higher nest temperatures (∼2 °C warmer), shorter incubation periods and poorer incubation success than those in tree-shade. Ground-cover-vegetated nests in tree-shade had lower hatching and emergence success (73%, 66% respectively) than sun-exposed nests placed in sites cleared of ground-cover vegetation (79%, 83% respectively). Hatchlings that emerged from cooler, tree-shaded nests were also larger and crawled faster than hatchlings from sun-exposed nests. We suggest for conservation projects on naturally 'hot' beaches, active management strategies such as selective groundcover vegetation removal and increased shading could be implemented to increase high quality hatchling production. Image 1 • Sun-exposed nests were 2 °C warmer than tree-shaded, but vegetation had no effect. • Vegetated + shaded nests had low hatching (73%) and emergence success (66%). • Cleared + sun nests had better hatching (79%) and emergence success (83%). • Shaded nests produced larger and faster hatchlings than sun-exposed nests. • Vegetation had no significant effect on performance or morphology of hatchlings. [ABSTRACT FROM AUTHOR]

Ultraviolet filters (UVFs) added to sunscreens (SS) are emerging contaminants in marine environments due to their adverse effects on organisms and ecosystems. UVFs have also been detected in beach-dune systems, but their influence on resident organisms has not been explored yet. Native plants are fundamental components of coastal dunes, and these ecologically/economically important systems are currently among the most threatened globally. Thus, understanding whether UVFs may act as threats to dune plants is crucial. This field study evaluated and compared the effects of titanium dioxide nanoparticles (nTiO 2), one of the inorganic UVFs most commonly added to sunscreens, and those of a commercial sunscreen product containing it (SS-nTiO 2) on the performance of adult dune plants of a native (Thinopyrum junceum) and a non-native invasive species (Carpobrotus sp. pl.) and their competitive interactions at environmentally realistic concentrations. The effects of nTiO 2 , SS-nTiO 2 and of a sunscreen product containing just organic UVFs (SS-OF) on early life stages of T. junceum were also examined. Ti bulk content in sand and plants at the study site ranged from 970 to 1069 mg kg−1 and from 2 to 7.9 mg kg−1, respectively. Thinopyrum junceum adult plants periodically exposed during the summer season to seawater contaminated by SS-nTiO 2 produced less biomass than un-exposed plants and nTiO 2 exposed plants. nTiO 2 and SS-nTiO 2 reduced the capacity of T. junceum to control the spread of Carpobrotus. Both SS-nTiO 2 and SS-OF reduced seedling emergence in T. junceum whereas nTiO 2 did not. These results demonstrated that the periodical exposures of native dune plants to sunscreens could reduce their establishment success and growth and favor invasive plant spread potentially resulting in community structure changes. They also emphasize the need to assess the phytotoxicity not only of single UVFs but especially that of complete sunscreen products to design more eco-friendly formulations in the future. [Display omitted] • UVF and sunscreen (SS) are pollutants of emerging concern for coastal environments. • UVF nTiO 2 alone did not affect the growth of dune plants. • SS containing nTiO 2 reduced the growth of a native plant. • nTiO 2 and SS-nTiO 2 reduced native plant ability to control invasive plant spread. • SS-nTiO 2 and SS containing organic filters reduced native plant seedling emergence. [ABSTRACT FROM AUTHOR]

The temporal variation in vegetation cover in aeolian sedimentary systems, especially those in arid regions, provides an indication of environmental change. Based on this, the objective of this paper is to design a simple method for classifying the vegetation density of arid aeolian sedimentary systems through the digital processing of aerial images. The green band of a high resolution orthophoto of La Graciosa island (Canary Islands, Spain) is used as an example. The pixels identified as vegetation were vectorized to point geometry, the vegetation density was then calculated, and a digital vegetation density model (DVDM) thereby obtained. Both spatial and statistical analyses were performed to find the optimal procedure to achieve the objective. Speed, objectivity, cost, and the possibility of working with historical records are discussed, and the proposed method is compared with others based on visual analysis or digital remote sensing. The importance of this method for countries with less research funding or low GDP per capita is also discussed. The proposed procedure opens up future lines of research for comparison of results across various environmental and anthropogenic variables. In addition, vegetation density can be used as a variable in computational fluid dynamic modeling of vegetation in arid dune systems. [ABSTRACT FROM AUTHOR]

LiDAR (Light Detection and Ranging) has been used to investigate coastal landform morphology, evolution, and change for almost a decade. Repeated airborne LiDAR surveys can provide the scientific community with significant observations of how shorelines have evolved, which may then enable forecasts of future patterns of change. However, there have been few studies that have considered the application of this new technology to the specific study of foredune morphology and vegetation. The accuracy and appropriateness of airborne LiDAR needs to be assessed, particularly where the density of vegetation may obscure the underlying topography, prior to interpreting derived geomorphic features. This study: i) tests the vertical accuracy of airborne LiDAR in 37 foredune systems along the coast of south-eastern Australia, and ii) demonstrates that it can be used to describe foredune morphology and vegetation in considerable detail. There was a strong correlation between the remotely-sensed LiDAR-derived elevation and field topographic and vegetation surveys (R 2 = 0.96). A protocol for obtaining foredune geomorphic and botanical parameters is described. It enables widespread biogeomorphic characterisation along coasts for which LiDAR data is available, which can benefit both coastal managers and researchers alike. [ABSTRACT FROM AUTHOR]

Dunes are important for coastal protection, but their presence can sometimes be seen as conflicting with the recreational use of the coastline. In June 2014, in response to community concern, Wollongong City Council, a local government authority in southeast Australia, took the unconventional step of removing vegetation and re-profiling the foredune in a section of Woonona Beach to improve beach width and sightlines. A series of cross-sections in the re-profiled and adjacent unmodified areas have been surveyed monthly since July 2013, to help determine the impact of the intervention on beach and foredune topography. These show that immediately after re-profiling, considerable additional lower beach width was gained, and there was little accretion on the foredune that had been re-profiled. However, after 8 months, the importance of the re-profiling in maintaining lower beach width is less clear, and an incipient foredune is emerging at the new vegetation line, with about half the volume of sand removed during re-profiling re-deposited in this area. After 21 months, lower beach width gain from re-profiling had disappeared, and the volume of sand deposited on the new incipient foredune is more than the volume removed by the re-profiling. The results are discussed in terms of whether the short-term outcomes achieved by the re-profiling are being compromised, and what on-going management will be required to maintain these over the longer term. This study highlights the challenges facing coastal managers trying to balance conflicting community objectives at beaches backed by vegetated dunes. [ABSTRACT FROM AUTHOR]

Gómez, J.F.; Byrne, M.-L.; Hamilton, J., and Isla, F., 2017. Historical coastal evolution and dune vegetation in Isla Salamanca National Park, Colombia. This paper analyzes the relationship between coastal dynamics and vegetation over dunes in Isla Salamanca Road Park (ISRP), a biosphere reserve and Ramsar site located on the Colombian Caribbean coast. Historical coastline changes together with the main geomorphological features were surveyed through fieldwork, satellite images, and historical aerial photographs, revealing that erosion is the predominant process in the eastern and central sectors of ISRP, and accreting trends throughout time occur in the westernmost sector of the study area. Dunes in the central and eastern sectors are scarped and regularly affected by storm wave action, whereas on the western end of the study area, embryo dunes are currently forming and evolving. Based on the mapped landforms and coastline trends for the last six decades, 1-square-m quadrats were used to identify dune vegetation over six cross-shore transects next to stretches of coast under moderate erosion (eastern sector), high erosion (central sector), and accretion (western sector). The vegetation diversity index indicates that the scarped dunes in the eastern and central sectors have more diverse and mature species cover than the embryo dunes located in the western sector. The former is populated by late successional species, whereas the latter is populated by pioneer vegetation species that can thrive under sand burial. These outcomes reveal the underpinning effect that coastal dynamics and past coastal changes have in the present landscape and vegetation associations along ISRP. [ABSTRACT FROM AUTHOR]

Arid transgressive coastal dune fields experience significant changes over short time periods. They are ideal systems to analyze environmental changes induced by human activities. This research analyzes the changes in vegetation produced by tourism in the dune field of Maspalomas (Gran Canaria, Canary Islands, Spain). Plant communities were mapped using GIS in digital ortophotos before tourism development in 1961 and then in 2003. The layers were overlaid in a GIS to analyze variations in the spatial distribution and extension of the vegetation. Detected changes were grouped into five types: no change, urban occupation, plant colonization, plant community changes and vegetation loss. Half of the dune system presented no change in vegetation. The most significant modifications were associated with urban occupation (tourist urbanizations, infrastructures and tourist facilities) and plant colonization. Urban occupation decreased the dune system surface area and resulted in disappearance or reduction of three plant communities. Plant colonization was indirectly induced by tourism infrastructure development, since it modified wind flow, there by stabilizing the dunes in some areas and forming deflation surfaces in others. The changes in spatial extent of plant communities are bioindicadors of environmental changes arising from tourism development. Vegetation changes in this study reflected stabilization processes (colonization and expansion of psammophilous herbaceous and xerophilous shrub plant communities), erosion (colonization as well as the expansion of hygrophilous and halophilous plant communities) and anthropogenic processes (occurrence of ruderal plant communities). [ABSTRACT FROM AUTHOR]