The geography of Feniglia is what makes it botanically exceptional. The dune system stretches roughly six kilometres long and one kilometre wide, covering about 4.92 square kilometres and rising no more than 14 metres above sea level. Together with another sandy strip, it encloses the Orbetello lagoon, cutting it off from the open Mediterranean Sea. According to the researchers, coastal dunes that lie in direct contact with coastal lagoons are genuinely rare in the Mediterranean Basin, where only about 54 main coastal lagoons exist and lagoon shores are typically dominated by shrubs or herbs rather than forest. Feniglia, by contrast, packs pine forest, dune and lagoon macrohabitats into a single narrow isthmus, a configuration that has earned it recognition as a protected biotope and as a distinctive biotope of the Mediterranean macchia.

The isthmus itself is a young landform, built during the late Quaternary period as carbonate-rich sands eroded from Monte Argentario were transported by sea waves and strong southwesterly winds. Its creation converted what was once an island of the Tuscan Archipelago into a promontory, and it now functions as an ecological corridor linking the peninsula to this former island, a connection of considerable biogeographical significance given the endemic animals and plants of Argentario. The sands that built the dune, however, nearly destroyed the lagoon when human mismanagement set them in motion again.

In the early 1800s, the municipality of Orbetello sold the dune to private owners who exploited it intensively for grazing and logging. Deforestation allowed sand to pour into the Orbetello lagoon, creating shallow marshes, harming fishing and increasing the risk of malaria. Authorities responded by building canals to improve water circulation, and reforestation plans were drafted around 1900, though landowners’ opposition delayed them until a 1910 law designated all of Feniglia as public land. In 1911, a consolidation and reforestation project began, mainly planting maritime pine and stone pine to stop the lagoon from silting up, alongside Mediterranean dune species such as Calamagrostis arenaria subsp. arundinacea, Cakile maritima, Juniperus macrocarpa, Euphorbia paralias and Medicago marina. The works covered about 360 hectares until 1925, and the forest eventually expanded to roughly 460 hectares. The researchers note this is likely the oldest ecological rehabilitation operation in Europe, and the new inventory was undertaken more than a century after it began.

Compiling the checklist demanded substantial detective work. The team retrieved all past botanical research conducted entirely or partly in the study area, from nineteenth-century surveys to studies carried out shortly after reforestation began and others conducted 70 to 80 years later, and complemented this data mining with fresh field surveys in 2023. Species recorded before the reforestation were excluded from the analyses, as were erroneous reports identified in theses, and planted species were counted only if they had naturalised. Collected specimens are preserved in the herbaria of Siena and Viterbo, and identifications followed standard Italian and European floras, with nomenclature aligned to the most recent checklists of the Italian flora. Each taxon was assigned a life form, a chorological type and ecological indicator values, and classified into preferential macrohabitats of forest, dune or lagoon to allow separate analyses.

The resulting inventory shows a flora dominated by three families: Poaceae with 72 taxa, Asteraceae with 54 and Fabaceae with 52, a pattern broadly consistent with the Italian flora as a whole, though with the first two families reversed. The high number of grasses reflects the presence of xerophilous, discontinuous small grasslands, including a priority habitat under the EU Habitats Directive that occurs as a mosaic in the pine forest understorey. The abundance of Amaranthaceae, with genera tied to coastal salt marshes, and Cyperaceae, linked to wet habitats, mirrors the isthmus’s brackish lagoon and freshwater wetlands. The genus Trifolium stands out with 16 taxa, likely favoured by sandy, silica-rich soils and numerous dry grasslands, while the natural presence of numerous Quercus species in such a limited area is noteworthy enough that the authors suggest it merits a dedicated study. Vascular cryptogams, by contrast, are represented by only two species, a scarcity the researchers attribute to limited summer water availability and the absence of rocky substrates.

A species-area analysis revealed that the observed flora is far richer than expected for an area of this size. The 502 recorded taxa exceed the predicted value of 377 by more than 33 percent, with native species exceeding expectations by 27.35 percent and alien species by 42.11 percent. The life-form spectrum is dominated by therophytes, short-lived plants that complete their cycle quickly and thrive on well-drained, nutrient-poor soils, followed by hemicryptophytes and phanerophytes. The ratio of hemicryptophytes to therophytes, at 0.54, reflects a Mediterranean-type bioclimate consistent with values reported for nearby protected areas. The chorological spectrum tells the same climatic story: Mediterranean species lead with 157 taxa, followed by Euromediterranean and Eurasiatic elements, confirming the picture painted by the biological forms and matching findings from other Tuscan coastal areas such as Monte Argentario, Diaccia Botrona and Lake Burano.

The conservation headline figures are striking. The inventory includes 15 species of the Tuscan Attention List and 3 species of the Italian Red List, alongside 3 Italian endemics: Ornithogalum exscapum, found in the pine forest; Limonium multiforme, endemic to the Tuscan coast from Livorno to the Ansedonia promontory; and Linaria purpurea, widespread in central and southern Italy. Sixteen species are considered rare in Tuscany, including Atriplex littoralis, whose Feniglia lagoon populations are the only recent and certain ones in the region and represent the southern limit of the species in Italy. Juncus sorrentinoi, known nationally only from Sardinia and Tuscany, is recorded here as only the second site for the region. Maresia nana, a psammophilous dune specialist, appears to survive in Tuscany at Feniglia alone. Staphisagria macrosperma, collected in the region over a century ago, persists in locally abundant populations near the reserve entrance on the Ansedonia side. Four species reach their northern distribution limit at Feniglia, and three species were found to be new for the province of Grosseto.

Alien species, often the bellwether of ecological degradation, are surprisingly scarce. The team found 26 alien species at the Italian level, of which 15 are invasive, 9 naturalised and 2 casual, a relatively low presence the researchers interpret as an excellent indicator of naturalness, especially since most occur with very limited populations. Of the numerous non-native species trialled during the historic reforestation experiments, including radiata pine, Monterey cypress and black locust, very few have naturalised and the majority are no longer present. Two discoveries stand out: Monterey cypress is reported as new to Tuscany, while white elm is new to the province of Grosseto. The lagoon environment, with its harsh salinity, anaerobic muddy substrate and fluctuating water levels, hosts no alien species at all and acts as a protective barrier for the isthmus. The authors also weigh in on the stone pine itself, noting that although some consider it alien in Italy, its Mediterranean origins and the persistence of dune species in its understorey mean not all authors agree on its alien status.

The study’s conclusions carry a message that extends well beyond one Tuscan dune. Feniglia has transitioned from shrubland to pasture to dune to forest over the past two centuries, yet it still supports species of particular conservation interest, many of them rare or at their geographical limits, and its low alien load signals genuine naturalness. The researchers argue that the multiple layers of protection now covering the area, as a State Nature Reserve, a Special Protection Area and part of Special Areas of Conservation, have been decisive in preserving its plant diversity despite the environmental upheavals of the last century and the tourist pressure of each summer. As a benchmark for future research in botany and related fields, the inventory demonstrates that floristic surveys, though time-demanding and increasingly neglected, remain the foundation for understanding and conserving natural heritage, and that well-designed protection can allow even a heavily modified landscape to recover its botanical soul.

Subject of Research: Floristic inventory of the vascular flora of the isthmus of Feniglia Nature Reserve in southern Tuscany, Italy

Article Title: Vascular flora of the isthmus of Feniglia (southern Tuscany, Italy)

Article References: Fiaschi, T., Bonari, G., Frignani, F., Gizzi, G., Landi, M., Magrini, S., Quilghini, G., Pafumi, E., Scoppola, A., & Angiolini, C. (2024). Vascular flora of the isthmus of Feniglia (southern Tuscany, Italy). Italian Botanist, 17, 77-101. https://doi.org/10.3897/italianbotanist.17.122982

Image Credits: AI Generated

DOI: 10.3897/italianbotanist.17.122982

Keywords: Feniglia, Tuscany, Italy, vascular flora, Mediterranean, coastal dunes, biodiversity, conservation, alien species, pine forest, Orbetello lagoon, endemic plants

The classes concerned are Ammophiletea arundinaceae, the vegetation of shifting dunes dominated by Ammophila arenaria subsp. arundinacea; Honckenyo peploidis-Elymetea arenarii, the communities of stable dune grasslands of northern Europe; and Koelerio glaucae-Corynephoretea canescentis, the grey dune vegetation of the Mediterranean and Atlantic coasts. The revision, carried out by a team led by Corrado Marcenò and colleagues, reviews the original diagnoses and descriptions of every syntaxon name in these classes, checks the name-giving taxa against the most authoritative recent floras and checklists, and proposes corrections, mutations and, in two cases, formal conservation of names.

Phytosociology, the science of classifying plant communities, uses a hierarchical system of syntaxa: classes, orders, alliances and associations. Each syntaxon name is formed from the scientific names of its characteristic species, the name-giving taxa, and is governed by the ICPN, which operates on the principle of priority: the earliest validly published name is the correct one, unless it is conserved or corrected. The revision follows the fourth edition of the ICPN published by Theurillat and colleagues in 2021, which refined the rules for validating, correcting and typifying syntaxon names.

One of the most consequential outcomes of the revision concerns the class Ammophiletea arundinaceae. The authors demonstrate that the order Ammophiletalia was already validly described by Braun-Blanquet in 1933, dealing with Mediterranean vegetation, and that the name Ammophiletalia Braun-Blanquet et Tüxen ex Westhoff et al. 1946, adopted by Mucina and colleagues in the EuroVegChecklist of 2016, is therefore a later synonym. Because only Ammophila arenaria subsp. arundinacea is listed in the original tables of Braun-Blanquet’s 1933 study, this subspecies is the unambiguous name-giving taxon of both the order and its holotype alliance, Ammophilion arundinaceae.

However, the alliance name Ammophilion arundinaceae Braun-Blanquet 1933 and the association Medicagini marinae-Ammophiletum arundinaceae Braun-Blanquet 1933 face a nomenclatural problem: under the ICPN, the correct names would be Ammophilion arenariae and Medicagini marinae-Ammophiletum arenariae, based on the 1921 publication by Braun-Blanquet. Because these widely used names would otherwise be displaced by older, less familiar forms, the authors submit two formal proposals (numbers 37 and 38) to conserve the names under Article 52 of the ICPN. Conservation proposals are reviewed by the European Vegetation Classification Committee (EVCC), the body established by the Working Group European Vegetation Survey of the International Association for Vegetation Science, which evaluates such requests according to established procedures before names are adopted on the European vegetation classification website floraveg.eu.

The revision also resolves a long-standing dispute over the alliance Ononidion ramosissimae Pignatti 1953. Various authors, including Rivas-Martínez and colleagues and Mucina and colleagues in the EuroVegChecklist, had considered this name invalid, either as a nomen dubium or because the bibliographical reference to Braun-Blanquet’s 1933 study was not in the same part of Pignatti’s work as the description of the alliance. The authors show, however, that Pignatti validly published the alliance by including the association Crucianelletum maritimae Braun-Blanquet 1933 with a sufficient bibliographical reference in the last part of his study. Consequently, Ononidion ramosissimae has priority over the later homotypic synonym Crucianellion maritimae Rivas Goday et Rivas-Martínez 1958, which had been considered the valid name.

Another significant correction involves the alliance Diantho attenuati-Scrophularion caninae, originally published as Diantho-Scrofularion humifusae by Baudière and Simonneau in 1974. The name-giving taxon Dianthus pyrenaicus subsp. catalaunicus must be corrected to Dianthus pyrenaicus subsp. attenuatus, because Nyman formally established the autonym Dianthus attenuatus Sm. subsp. attenuatus in 1878–1882, giving the epithet attenuatus nomenclatural priority over catalaunicus at the subspecies rank. Similarly, Scrophularia humifusa is treated as a synonym of Scrophularia canina in current taxonomic literature, prompting a mutation of the alliance name. The associated association Diantho attenuati-Corynephoretum canescentis is likewise corrected, and the authors demonstrate that the name is validly published because the original tables contain relevés with both Corynephorus canescens and Dianthus catalaunicus.

The revision also addresses the nomenclature of the northern European dune grasslands of the class Honckenyo peploidis-Elymetea arenarii. The order originally published as Elymetalia gigantei Vicherek 1971 must be corrected to Leymetalia racemosi, because Elymus giganteus Vahl is a later taxonomic synonym of Leymus racemosus, and the prevailing taxonomic approach assigns this species to the genus Leymus. The same reasoning applies to the alliance Leymion racemosi and the association Leymetum racemosi, both originally published by Morariu in 1957 as Elymion gigantei and Elymetum gigantei. In the class Honckenyo peploidis-Elymetea arenarii, the authors mutate the class name itself to reflect the current taxonomic treatment of Leymus arenarius, formerly Elymus arenarius, and correct the order name to Leymetalia arenarii, which takes priority over the later Honckenyo-Elymetalia arenarii Tüxen 1966.

The class Koelerio glaucae-Corynephoretea canescentis, the grey dune vegetation of the Mediterranean and Atlantic coasts, also receives substantial nomenclatural attention. The order Artemisio-Koelerietalia albescentis Sissingh 1974 is corrected to Artemisio crithmifoliae-Koelerietalia albescentis, because the correct name for Artemisia lloydii Rouy at the species level is Artemisia crithmifolia L. The authors note that while Flora Iberica accepts Artemisia crithmifolia as a species, other taxonomic works include it in Artemisia campestris subsp. maritima, but a mutation to Artemisio maritimae would be a source of confusion because there is also the accepted species name Artemisia maritima L. The alliance Euphorbio portlandicae-Helichrysion stoechadis and the association Artemisio crithmifoliae-Ephedretum distachyae are likewise corrected. The alliance Koelerion arenariae Tüxen 1937, originally published as Koelerion albescentis, is mutated because Koeleria albescens occurs exclusively on the Atlantic coastal dunes of France and Spain, whereas Koeleria arenaria has a wide range including the coastal areas of the Netherlands and Germany where the original relevés were sampled.

The revision also touches on the nomenclature of bryophytes and other taxa in the grey dune communities. The association Syntrichio ruraliformis-Phleetum arenarii, originally published by Braun-Blanquet and De Leeuw in 1936 as Tortula ruraliformis-Phleum arenarium-Assoziation, is mutated to reflect the current taxonomic treatment of the moss Syntrichia ruraliformis, formerly Tortula ruraliformis. Similarly, the alliance Syntrichio ruraliformis-Lomelosion argenteae and the association Syntrichio ruraliformis-Lomelosietum argenteae, originally published by Pignatti in 1952 as Tortuleto-Scabiosetum, are mutated to reflect the current treatment of Lomelosia argentea, formerly Scabiosa argentea. The authors note that while various floras include Scabiosa ucranica in the synonymy of Scabiosa argentea, they follow the taxonomic treatment used in Eastern European floras where these taxa are not considered conspecific, based on morphological characters and ecology.

The nomenclatural revision is more than an exercise in botanical bookkeeping. The syntaxa of European coastal dune vegetation are the reference units for conservation assessment, habitat mapping and monitoring across the continent, and unstable or ambiguous names undermine these applications. By aligning the classification with the fourth edition of the ICPN, checking every name-giving taxon against authoritative floras, and submitting two formal conservation proposals for the most widely used dune community names, the authors provide a stable nomenclatural foundation for the European vegetation classification. The revised syntaxonomic framework, including syntaxa with no nomenclatural issues that are officially accepted in the EuroVegChecklist, is presented in the appendices of the study, offering readers a comprehensive context and reaffirming the validity of the accepted names.

Subject of Research: Nomenclatural revision of European coastal dune vegetation syntaxa following the fourth edition of the International Code of Phytosociological Nomenclature

Article Title: Nomenclatural revision of the syntaxa of European coastal dune vegetation

Article References: Marcenò, C., Danihelka, J., Dziuba, T., Willner, W., & Chytrý, M. (2024). Nomenclatural revision of the syntaxa of European coastal dune vegetation. Vegetation Classification and Survey, 5, 27-37. https://doi.org/10.3897/vcs.108560

Image Credits: AI Generated

DOI: 10.3897/VCS.108560

Keywords: phytosociology, coastal dunes, vegetation classification, nomenclature, ICPN, Europe, Ammophiletea, Koelerio-Corynephoretea, Nomenclatural, revision, syntaxa, European

The index was developed specifically for the Black Sea’s unusual coastal regime. Unlike the macro- and mesotidal environments where most existing dune assessment frameworks were conceived, the Black Sea is a microtidal, fetch-limited basin in which wind-generated waves, episodic storm surges and aeolian transport dominate, while tidal forcing is negligible. Under these conditions dune systems persist over longer timescales, sediment–vegetation feedbacks are more stable and successional stages reach greater maturity than on high-energy tidal coasts. Directly transferring indices built for tidal environments is therefore problematic, a limitation the study’s authors set out to address.

Technically, the EGDVI groups its 31 indicators into eight thematic categories: Geomorphology (five indicators, weighted 30%), Aeolian Dynamics (four indicators, 6%), Ecology (five indicators, 26%), Pressure/Risk/Stress (four indicators, 7.5%), Human Footprint (four indicators, 9.5%), Legal Protection and Management (five indicators, 10%), Scientific Importance (two indicators, 4%) and Nature Conservation (two indicators, 7%). Every indicator is scored on a standardised 0–4 scale, where higher values indicate greater natural value or better condition; for pressure-type indicators the logic is inverted so that higher scores always mean lower risk. Weighted scores are calculated as the product of each indicator score and its percentage weight, and the total EGDVI score is the sum of all 31 weighted scores, with a theoretical maximum of 400 corresponding to an ideal state in which every indicator reaches its highest value.

Indicator weights were not chosen arbitrarily. An interdisciplinary panel of coastal geomorphologists, dune ecologists and conservation practitioners first submitted independent weight proposals with justifications for each indicator and category; a second consensus round then reconciled differences and normalised the final weights to sum to 100%. Indicator scores themselves were derived from field surveys conducted between May and September 2025, high-resolution UAV photogrammetry and LiDAR transects, GIS analysis of shoreline position, dune width and infrastructure footprints, legislative and cadastral databases, and scientific literature and habitat inventories. Where data for a given indicator were unavailable, its weight was redistributed proportionally within the same category to preserve the overall balance.

Classification followed a hybrid two-step strategy. Jenks Natural Breaks optimisation was first applied to the pilot dataset to identify natural groupings and knife-edge cases, after which fixed reference thresholds were defined as percentages of the maximum score: Class A (Very High) at 320 or above, Class B (High) at 280–319, Class C (Moderate) at 220–279, Class D (Low) at 160–219 and Class E (Degraded) at 159 or below. This preserves Jenks’s statistical robustness for initial diagnostics while providing stable, transferable benchmarks for national monitoring frameworks. Sensitivity analyses confirmed the framework’s reliability: across one-at-a-time weight perturbations of ±10–20% and category-level scenarios shifting weight shares by up to ±15% between paired thematic categories, the rank order of dune systems remained highly stable, with changes limited to at most one class step and Spearman’s rank correlation between baseline and perturbed ranks exceeding 0.90.

Applied to the 16 Strandzha dune systems — which together cover 101.89 hectares, roughly 10.3% of Bulgaria’s total dune area — the index produced total scores ranging from 154.0 to 364.5 out of 400, a striking spread for a relatively compact coastal sector. Four systems (25.0%) achieved Class A Very High Value: Primorsko (Stomopolu–Perla), Primorsko (International Youth Centre), Koral, and Camping Yug and Lipite, with a class mean of 347.4 and a narrow interquartile range indicating that all four approach near-reference conditions. These sites combine wide, continuous dune belts often exceeding 100–150 metres, well-developed morphological sequences from embryonic dunes to foredunes and secondary ridges, high vegetation integrity with clear zonation, comparatively low anthropogenic pressure and favourable legal protection. Atliman stood alone in Class B with a score of 283.5, occupying a knife-edge transitional position where relatively minor shifts in management effectiveness could trigger upward or downward reclassification.

The regional picture is dominated by the middle of the scale. Eight systems (50.0%) — including the Veleka River Mouth, Kiten, Butamyata, Ahtopol, Listi, Silistar, Nestinarka and Oazis — fall within Class C Moderate Value, with a class mean of 258.9 and limited internal dispersion. Most retain functional dune units and key geomorphological elements yet show varying degrees of fragmentation, reduced sediment connectivity and visible anthropogenic influence in the foredune zone. Lozenets scored as Class D Low Value, marked by a narrow, discontinuous dune belt, disrupted vegetation cover and diminished morphodynamic function, while Tsarevo (Popski plazh) and Arapya landed in Class E Degraded, exhibiting extensive loss of frontal dune ridges, sparse psammophytic vegetation and a near absence of coastal-protection function. The regional mean score of 266.1 and median of 261.2 both fall within the moderate-value class, confirming that transitional dune systems dominate the Strandzha coast rather than a landscape uniformly pristine or uniformly ruined.

A detailed case study of the top-scoring site, Primorsko (Stomopolu–Perla), with its total of 364.5, illustrates how the index dissects a dune system dimension by dimension. All five geomorphological indicators received the maximum score of 4, reflecting dunes both higher than 5 metres and wider than 100 metres with fully functional hydrogeomorphic connectivity and no fragmentation. Aeolian dynamics indicators scored 3, indicating a system that is active but stable, with blowouts limited to under 10% of extent and sand supply sufficient to sustain development. Ecological indicators also reached 4, confirming vegetation cover above 60% with strong representation of pioneer species such as Ammophila and Elytrigia alongside typical psammophytes and several conservation-priority habitat types. Pressure indicators told a more nuanced story: marine exposure scored just 1, reflecting strong wave energy and frequent storm overwash at the dune front, while degradation risk scored 3, macro-litter pollution 3 and invasive alien species 2, signalling limited but detectable ecological disturbance.

The governance dimension of the case study proved equally revealing. Land ownership and access regulation, cadastral recognition and scenic value all scored 4, and protected area status scored 3, yet the absence of designation under EU or national restoration frameworks scored 0 — a clear policy gap showing that even Bulgaria’s most valuable dune system is not yet integrated into strategic restoration planning. Recreational use intensity scored 2, indicating moderate visitor pressure with localised trampling during peak seasons, and periodic mechanical beach cleaning scored 3. This capacity to capture both outstanding conservation value and subtle institutional shortcomings is precisely what distinguishes the EGDVI from simple ranking approaches, the authors argue, and what strengthens the science–policy interface by ensuring that legal recognition and research relevance are explicitly quantified rather than treated qualitatively.

The study’s authors position the EGDVI as complementary to, rather than a replacement for, the conservation status assessments Bulgaria reports under Article 17 of the EU Habitats Directive, which suffer from considerable uncertainty due to limited standardised field-based monitoring and methodological inconsistencies in Natura 2000 implementation. By combining fixed classification thresholds with sensitivity analysis and explicitly linking classes to management pathways — strict protection and monitoring for Class A, preventative measures such as boardwalks and fencing for Class B, targeted restoration for the numerically dominant Class C, and progressively more demanding rehabilitation for Classes D and E — the index moves beyond descriptive assessment towards actionable conservation planning. Its conceptual structure is considered transferable to other microtidal and enclosed-sea coastal environments, from the Baltic to parts of the Mediterranean, provided that indicators are locally calibrated, and future refinements incorporating time-series observations, UAS- and LiDAR-based mapping and machine-learning approaches are expected to further enhance its analytical resolution.

Subject of Research: Development and pilot application of a multi-criteria dune conservation assessment index on the Bulgarian Black Sea coast

Article Title: Development and application of the Eco-Geomorphological Dune Value Index (EGDVI) for assessment of conservation status: a pilot case at the Strandzha Black Sea Coast, Bulgaria

Article References: Prodanov, B., Bekova, R., Valcheva, M., Tzonev, R., & Baltakova, A. (2026). Development and application of the Eco-Geomorphological Dune Value Index (EGDVI) for assessment of conservation status: a pilot case at the Strandzha Black Sea Coast, Bulgaria. One Ecosystem, 11, Article e189660. https://doi.org/10.3897/oneeco.11.e189660

Image Credits: AI Generated

DOI: 10.3897/oneeco.11.e189660

Keywords: coastal dunes, EGDVI, conservation index, Black Sea, Bulgaria, Strandzha, coastal geomorphology, dune ecology, microtidal coast, science-policy interface, Development, application

Coastal dunes are among the most underappreciated ecosystems on Earth. They buffer inland areas from storm surges, trap sand that would otherwise erode beaches, store carbon, and harbor specialized plants and animals found almost nowhere else. Yet along the North African Atlantic coast, they face a double squeeze: rising human pressure from tourism, construction, grazing and trampling, and increasing aridity driven by climate change. Previous work on Moroccan coasts has documented alarming coastal vulnerability, including erosion and flooding risks amplified by sea-level rise. What has been missing, the authors argue, is fine-grained ecological data on the dune vegetation itself, the kind of baseline needed to justify and direct conservation action before the habitat is gone.

The research team, led by Jihane Tellal and Said Moukrim of Mohammed V University in Rabat together with colleagues from the National School of Forest Engineers and Chouaib Doukkali University, carried out 123 phytoecological surveys distributed across three dune facies: embryonic dunes closest to the beach, the primary foredune, and the backdune. Each 16-square-meter plot was recorded using the classic Braun-Blanquet approach, the century-old method of plant sociology that scores species presence and cover, combined with modern statistical tools. In total they recorded 53 vascular plant taxa belonging to 50 genera and 26 families. That tally included one endemic taxon, one near-endemic, and one threatened species, a reminder that even a species-poor dune system can hold irreplaceable biological heritage.

The numbers themselves tell a stark story about the condition of the ecosystem. Average species richness across all stations was just 5.13 species per plot, an exceptionally low figure for coastal dunes, which in better-preserved Mediterranean sites can support far richer communities. Richness differed sharply between zones: embryonic dunes averaged only 3.78 species per plot, while the primary foredune held 6.54, a statistically significant difference confirmed by a Kruskal-Wallis test with p below 0.001. The pattern follows a well-known ecological rule of thumb, that the harshest conditions closest to the sea, with salt spray, sand burial and nutrient poverty, filter out all but the toughest specialists, while conditions relax slightly inland.

The life-form spectrum reinforced the semi-arid, sandy character of the flora. Therophytes, plants that complete their entire life cycle within a single favorable season and survive the rest as seed, dominated at 34 percent, followed by geophytes, which retreat to underground bulbs and rhizomes during drought, at 18.9 percent. This signature, first formalized by the Danish botanist Christen Raunkiaer in the 1930s, is exactly what ecologists expect from a stressed, semi-arid psammophilous, meaning sand-loving, flora. It is a botanical fingerprint of a landscape where water is scarce, disturbance is frequent, and only opportunists and buried survivors can make a living.

Diversity indices painted a subtler picture. Shannon diversity values ranged from 0.650 to 0.957 across the dune zones, and Pielou evenness, a measure of how evenly individuals are distributed among species, ranged from 0.447 to 0.571. Intriguingly, pairwise comparisons between zones showed no significant differences for either index. The researchers attribute this homogenization to one culprit: Carpobrotus edulis. Because the invasive succulent dominates so many plots across all zones, it flattens the natural ecological differences between them. The marginal overall effect of dune zone on Shannon diversity, the authors conclude, reflects the invader’s differential dominance across facies rather than a uniform disturbance signal. In other words, the invasion is not just removing species; it is erasing the ecological structure of the dune landscape itself.

Multivariate analysis confirmed that genuine floristic differentiation among the three dune zones still exists, structured along the sea-to-inland environmental gradient. A PERMANOVA test, a non-parametric method for analyzing multivariate variance, returned an R-squared of 0.179 with p below 0.001, meaning that dune zone explains a meaningful share of the variation in community composition. This zonation, from the salt-tolerant pioneers of the embryonic dune through the dune-building grasses of the foredune to the more sheltered backdune communities, is the fundamental architecture of a healthy dune system. Each band plays a role in sand capture and stabilization, and losing any one of them weakens the whole protective structure.

The invasion dynamics, however, are the study’s most urgent finding. Carpobrotus edulis, known variously as hottentot fig or ice plant, was present in 51.2 to 70.7 percent of stations depending on the dune zone, and its mean cover in the backdune hit 93.8 percent. The plant’s strategy is brutally effective: it forms dense, impenetrable mats, its thick succulent tissues shade out seedlings, its fallen leaves alter soil chemistry, and it spreads both vegetatively and by seed dispersed by fruit-eating animals. A major meta-analysis led by Montserrat Vilà found that invasive alien plants like Carpobrotus consistently reduce native species richness and alter ecosystem processes. Recent Mediterranean studies have shown that even after Carpobrotus removal, recovery of native communities can be slow and incomplete, which makes early intervention far cheaper and more effective than later restoration.

The authors frame their findings as a call for integrated management rather than a single-fix solution. Their recommendations include mechanical control of invasive species, assisted restoration of native dune-building vegetation, and strict regulation of anthropogenic pressure such as trampling, vehicle traffic and uncontrolled development. The logic is interlocking: removing Carpobrotus without replanting native dune builders simply opens bare sand for reinvasion, while replanting without controlling human pressure condemns seedlings to being trampled. The work was supported by the BiodivRestore Program through the RESPOND Project, funded by Morocco’s Ministry of Higher Education, Scientific Research and Innovation, and builds on the team’s earlier research on environmental controls of psammophilous plant distribution in the same dune system.

What happens at Haouzia Bay matters far beyond one Moroccan bay. North African coastal dunes sit at the front line of climate change, with studies warning of alarming coastal vulnerability across the region’s deltaic and sandy beaches. Dune systems like this one are also biodiversity assets within the Mediterranean Basin, one of the planet’s recognized biodiversity hotspots. The Haouzia survey provides something rare for the region: a rigorous, plot-level baseline against which future change can be measured. If the 93.8 percent backdune cover of a South African succulent is not a wake-up call, it is hard to imagine what would be. The dunes of North Africa have survived millennia of wind and salt; whether they survive the next few decades of human pressure and biological invasion will depend on whether studies like this one translate into action on the ground.

Subject of Research: Floristic diversity and invasive species dynamics in North African Atlantic coastal dune vegetation

Article Title: Floristic diversity, biological spectrum and invasion dynamics of psammophilous vegetation in North African Atlantic coastal dunes (Haouzia Bay, Morocco): implications for conservation

Article References: Tellal, J., Rhazi, L., Lahssini, S., Boudjaj, A., El Madihi, M., Menzou, K., Ben Bammou, M., Malki, F., Tellal, R., & Moukrim, S. (2026). Floristic diversity, biological spectrum and invasion dynamics of psammophilous vegetation in North African Atlantic coastal dunes (Haouzia Bay, Morocco): implications for conservation. Plant Biosystems, 160(5), Article 290. https://doi.org/10.1007/s44473-026-00296-1

Image Credits: AI Generated

DOI: 10.1007/s44473-026-00296-1

Keywords: coastal dunes, Morocco, Carpobrotus edulis, invasive species, psammophilous flora, plant ecology, biodiversity, conservation, Atlantic coast, dune zonation, therophytes, habitat restoration

The challenge the researchers set out to solve is a familiar one in aeolian geomorphology. Traditional approaches, such as drift potential calculations and mobility indices, do a good job of describing wind-driven sediment transport at a given moment, but they offer limited ability to forecast whether dunes will migrate or become fixed over time. That gap matters increasingly in a changing climate, where shifts in wind regimes, precipitation patterns, and storm frequency may alter dune behavior with real consequences for ecosystems, roads, and homes. Complex numerical simulations could in principle fill the gap, but they demand data and expertise that many coastal regions simply do not have.

Toffani and Casadío turned instead to binomial logistic regression, a statistical technique that predicts the probability of a binary outcome, coded as zero or one, from a set of continuous predictor variables. First developed in the early 1980s, the method has been applied successfully to landslide susceptibility, soil mapping, and vegetation dynamics, yet its use for coastal dune mobility remained notably limited. The elegance of the approach lies in its ability to fold multiple climatic variables, including wind speed, precipitation, and large-scale atmospheric indices, into a single probabilistic framework that outputs a forecast probability of dune activation rather than a static description.

The natural laboratory for the study was the northern coast of the San Matías Gulf, stretching roughly 180 kilometers from the mouth of the Negro River to San Antonio Oeste. The region is a cold semi-arid environment where strong westerly winds blow hardest during the austral summer, exacerbating the aridity created by the Andean rain shadow. Its dunefields are remarkably varied: the Bahía Creek–Caleta de los Loros system extends over 36 kilometers with active dunes up to 16 meters high migrating east-northeast at 6 to 10 meters per year, while dunes near El Cóndor advance at around 7 meters per year. The area is also home to thousands of residents and a booming tourist trade, with Las Grutas alone averaging 118,000 visitors annually between 2006 and 2023, making dune encroachment a genuine practical concern.

To build their model, the researchers drew on hourly meteorological records from two stations, Viedma Aero and San Antonio Oeste Aero, covering the standard 1991 to 2020 reference period. Wind speeds and directions were normalized to a standard height of 10 meters, and winds exceeding 6.17 meters per second were flagged as capable of transporting sand, a threshold calculated from local grain sizes using Bagnold’s classic equations for the onset of saltation. From these data the team computed drift potential values and combined two established mobility measures, the Tsoar and Lancaster indices, into a new integrated index they dubbed TsoLa. Dunes were coded as active only when both indices simultaneously indicated mobility and the resultant drift direction aligned with the coast’s general eastward migration pattern.

The statistical screening was rigorous. Temperature, potential evapotranspiration, and soil moisture were excluded because of multicollinearity, while wave height, cattle populations, and the Southern Oscillation Index were dropped because they added little predictive power. What survived was a lean trio of predictors: monthly average wind speed, total monthly precipitation, and the Southern Annular Mode, or SAM, the dominant mode of extratropical climate variability in the Southern Hemisphere. When SAM is positive, the westerly wind belt contracts poleward and mid-latitude conditions turn warmer and drier; when it is negative, storm tracks shift north and the study region around 40 degrees south experiences stronger, stormier weather.

The results were strikingly consistent across both study sites. Wind speed emerged as a positive predictor of dune migration, with coefficients of 0.64 at San Antonio Oeste and 0.32 at Viedma, while both precipitation and SAM carried negative coefficients, meaning higher rainfall or a positive SAM phase reduces the probability of migration. In practical terms, the model suggests dune movement becomes unlikely when monthly precipitation exceeds 150 millimeters, when wind speeds fall below 20 kilometers per hour, or when SAM values are high. The models achieved area under the ROC curve values of 0.77 and 0.78, comfortably above the 0.5 threshold of random guessing, and correctly classified between 73 and 77 percent of observations in training and test datasets. A bootstrap analysis of 1,000 resamples confirmed that all three predictors had stable, statistically significant effects.

Validation against the real world came from nearly four decades of satellite and aerial imagery. The team digitized dune fronts in images spanning 1985 to 2023, placing reference points every 50 meters along each dune crest and measuring perpendicular distances between successive front positions. In the Viedma area, average migration rates ranged from 2.92 to 10.12 meters per year and correlated strongly with wind intensity values, with a correlation coefficient of 0.84. In San Antonio, migration was slower, between 2.51 and 6.01 meters per year, and showed little correlation with wind, likely because limited sand supply and encroaching vegetation, rather than wind energy alone, control movement there. Vegetation cover in the San Antonio area has in fact surged from 16 percent in 1961 to 60 percent in 2021, a greening trend the authors link to weakening winds and a trend toward more positive SAM values.

That contrast between the two dunefields carries an important lesson: geology matters. Viedma’s proximity to the Negro River mouth provides abundant sand that feeds large transverse dunes whose migration tracks wind capability closely, while San Antonio’s narrower beaches deliver a more limited sediment budget. The authors argue that integrating such geomorphological context into predictive models is essential, and they suggest that future refinements could incorporate higher-resolution vegetation indices, buoy-based wave data, better livestock records, and estimates of monthly sediment supply. They also note that lagged effects of El Niño events, which influence regional precipitation by up to 50 millimeters, deserve further study with properly calibrated time lags.

What makes the study resonate beyond Patagonia is its accessibility. Every input, from weather station records to the SAM index published by the British Antarctic Survey, is freely available, and the R scripts and datasets are posted in a public Zenodo repository. Because the framework relies on standard meteorological observations, it can be adapted to other coastal and inland aeolian systems with minimal modification, offering a scalable pathway for integrating climate forecasting with geomorphic hazard assessment. For coastal communities watching dunes advance toward their roads and homes, the message is empowering: the data needed to anticipate the next phase of dune activity may already be sitting in the nearest weather station’s archive.

Subject of Research: Statistical forecasting of coastal dune mobility using meteorological data and climate indices in northeastern Patagonia

Article Title: Forecasting coastal dune mobility: a logistic regression model driven by meteorological data and climate indices

Article References: Toffani, M., & Casadío, S. (2026). Forecasting coastal dune mobility: a logistic regression model driven by meteorological data and climate indices. Earth Surface Dynamics, 14(5), 801-820. https://doi.org/10.5194/esurf-14-801-2026

Image Credits: AI Generated

DOI: 10.5194/esurf-14-801-2026

Keywords: coastal dunes, dune mobility, logistic regression, aeolian geomorphology, Patagonia, Southern Annular Mode, wind erosion, climate indices, remote sensing, coastal management, sediment transport, Earth Surface Dynamics

Sand hoppers are familiar to anyone who has flipped over a mound of washed-up kelp on a California shore. The tiny, flea-like creatures shelter beneath seaweed wrack or burrow 10 to 30 centimeters into the sand during the day, emerging after dark to feed on decaying kelp. What makes them remarkable from a geological standpoint is their burrowing behavior. Unlike many burrowing animals that dig a single home and reuse it, sand hoppers construct an entirely new burrow each day in search of sand with precisely the right moisture content. Too wet, and the saturated sand behaves like a liquid, collapsing the burrow immediately. Too dry, and the powdery grains above the high tide line cannot hold a tunnel at all. The crustaceans seek what the researchers describe as a Goldilocks sweet spot in between, where the moisture is just right for a burrow to remain intact.

That daily search for the perfect building conditions means that sand hoppers are constantly excavating sand that has only recently been reworked by waves and wind, effectively resetting the surface of the beach on a nightly basis. David Hubbard, a marine scientist at UC Santa Barbara and a co-author of the study, has spent years studying these creatures up close, yet even he was unprepared for the scale of their activity. In a field experiment at Isla Vista Beach, the team returned one morning to find that some of their metal sampling frames, sectioned off the previous evening, had been completely buried under mounds of freshly excavated sand. The frames were invisible, and only the flags the researchers had prudently placed beside them allowed the plots to be relocated at all.

The experiment itself was elegantly simple. Tim Baxter, a physical geographer who led the work as a postdoctoral researcher with geography professor Ian Walker at UC Santa Barbara and is now a research fellow at the University of Oxford, designed the study around a straightforward question: how much sand are these animals actually digging? On a summer night at Isla Vista Beach, a bluff-backed stretch of shore adjacent to the UCSB campus, the team waited for high tide to pass and the water to recede, leaving the sand smoothed by waves. They then installed an array of metal frames in the zone where sand hoppers prefer to burrow, the damp band of sand between the saturated intertidal area and the dry powder above the high tide line. Overnight, the crustaceans within each frame dug their daily burrows, and in the morning the researchers collected and weighed every grain of sand that had been pushed to the surface.

The numbers were striking. Extrapolated across the shoreline, the excavated sand amounted to as much as 50 kilograms per meter of beach per day, a figure that stunned the team. Baxter described the result as the biggest shock of the study, noting that the researchers had not really expected such an impressive volume. When the team scaled their measurements across 25 kilometers of Southern California coastline, the total sediment displaced by sand hoppers proved comparable to the daily sediment loads of some major Southern California rivers and to the longshore drift processes that transport sand along the intertidal beach. In other words, an animal barely a centimeter long is moving sediment at a rate that competes with the physical forces conventionally credited with shaping the coast.

To appreciate why this matters, it helps to understand how sandy beaches function. Though they appear static, beaches behave like rivers of sediment, with sand constantly transported by waves, winds and currents. Each beach is one component of a larger system called a littoral cell, which cycles sediment from its sources, including eroding cliffs, dunes, and rivers and streams carrying material from coastal watersheds, through the beach itself, and onward along the coast. Beaches act as reservoirs within this conveyor belt of sand. While the physical processes of coastal sediment transport are well characterized, the contribution of the animals living in this highly dynamic environment has remained poorly understood, and the new study provides some of the clearest evidence yet that biology belongs in the sediment budget.

The implications extend beyond the beach surface itself. Sand hoppers are already recognized as a fundamental link in the coastal food web, consuming kelp wrack and in turn becoming prey for shorebirds and fish. Their burrowing adds another layer of ecological importance. The constant churning buries organic material such as kelp and carrion deposited on the beach, making it available to a different community of organisms living deeper in the sand, Hubbard explained. The burrows also aerate the sediment, delivering oxygen that supports aerobic microbial processes in layers of sand that would otherwise remain oxygen-poor. In effect, the crustaceans run a daily mixing and composting operation across the entire supralittoral zone.

The geomorphological consequences may be equally significant. By loosening the sand, the excavations make sediment more available to erosional forces of wind and water, Baxter noted, and the constant reworking potentially increases the roughness of the beach surface. That roughness, in turn, has implications for the formation of coastal sand dunes, landforms that depend on sand being picked up from the beach and deposited inland. This connection carries real-world weight, because coastal dunes have increasingly been embraced as a nature-based strategy for coping with coastal flooding and sea level rise. As self-building and self-healing landforms, dunes can absorb the force of increased wave and storm action, and understanding the biological processes that help feed sand into dune systems could improve how these natural defenses are managed.

The study also speaks to a broader shift in the earth sciences. The field of biogeomorphology, which examines the interactions between living organisms and the landscapes they inhabit, has gained considerable momentum over the past few decades, yet the influence of animals and plants on landforms remains understudied relative to purely physical processes. Baxter suggested that part of the reason is a lingering assumption that the effects of animals are temporary, localized and small. The sand hopper results challenge that assumption directly, demonstrating that biological activity can operate at scales that rival the great sediment engines of the coast. What the team set out to show, Baxter said, is that these activities and interactions operate on a far larger scale than commonly appreciated, and that their impacts deserve far more attention.

For now, the humble sand hopper has earned a new title: one of the highest rates of bioturbation of anything on the planet, in Hubbard’s words. The next time a walk along a California beach reveals a pockmarked surface of tiny burrow entrances and miniature sand mounds, it may be worth pausing. Each of those small craters marks a night’s work by an animal weighing a fraction of a gram, and together those nights of labor move sediment in quantities that reshape the coastline, feed the food web, cycle nutrients through the sand, and perhaps even help build the dunes that stand between coastal communities and the rising sea.

Subject of Research: Bioturbation and sediment transport by burrowing sand hopper crustaceans on California beaches

Article Title: Tiny beach-dwelling crustaceans are big-time sand movers, shaping the California coast

Article References: Tiny beach-dwelling crustaceans are big-time sand movers, shaping the California coast. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: sand hoppers, Megalorchestia, bioturbation, sediment transport, California beaches, coastal geomorphology, littoral cell, coastal dunes, UC Santa Barbara, Journal of Geophysical Research, biogeomorphology, amphipods

The study, published in the journal Environmental Monitoring and Assessment, was led by Juan Pablo Passetti of the University of Urbino together with colleagues from the University of Molise and partner institutions. The team set out to answer a deceptively simple question: do the beach-cleaning operations that keep tourist shores presentable change not just how much litter remains, but what kind? Their findings point to a systematic blind spot in the way Europe assesses coastal contamination, one that could make heavily managed beaches look cleaner than they really are.

Marine litter is one of the most pervasive threats to coastal ecosystems, and plastic is by far its dominant component. Coastal dune systems add another layer of complexity, because dune vegetation traps debris while wind and waves repeatedly bury and re-expose it. Most monitoring frameworks, including the European Marine Strategy Framework Directive’s Descriptor 10 and the OSPAR protocol, focus on macro-litter, defined as items larger than 25 millimeters, largely because such items are easy to count and obviously relevant to management. But a growing body of evidence indicates that meso-litter, fragments between 5 and 25 millimeters produced mainly by the breakup of larger plastic items, may be the numerically dominant fraction on beaches, even though it remains poorly integrated into official assessments.

Mechanical beach cleaning, the standard practice on tourist shores, typically uses tractor-drawn rakes and sand-sieving systems to lift visible debris from the sand. These machines are effective at removing large items, but particles smaller than the sieve mesh simply pass through or stay embedded in the sediment. That asymmetry led the researchers to a specific hypothesis: mechanically cleaned, non-vegetated sectors would contain less macro-litter than vegetated dune sectors, while meso-litter would be similar in both, leaving managed areas with a proportionally greater share of small fragments.

To test this, the team conducted seasonal surveys in February, April, July, and October of 2025 at three sites: Fiorenzuola di Focara, a cliff-associated area with coarse sediments and pioneer vegetation; Litorale della Baia del Re, a low-lying sandy-gravel system with developing dunes; and Spiaggia Libera Sottomonte, an unprotected coastal area with similar sediment characteristics. The first two sites fall within the European Union’s Natura 2000 network of protected habitats. At each site, the researchers established shore-perpendicular transects spanning both vegetated dune sectors and open, non-vegetated beach sectors, with transects separated by at least 100 meters in line with OSPAR recommendations.

Within each transect, four permanent plots of 2 by 2 meters were marked out, two in each area type, with positions randomly generated in GIS software and verified in the field. In total, 112 permanent plots were revisited across four seasons, yielding 448 plot-level sampling events. Every litter item was counted and classified as either macro-litter or meso-litter, then assigned to material categories including plastic, polystyrene, glass, paper, aluminum, and mixed materials. The open sectors at all three sites were subject to mechanical cleaning, while the vegetated dune sectors, which host protected psammophilous plant communities, were cleaned only by hand to avoid damaging vegetation and altering dune morphology.

The numbers were revealing. Across all sampling events, the team recorded 5,824 litter items over a total sampled area of 1,792 square meters, a raw density of about 3.25 items per square meter. Meso-litter accounted for a remarkable 84.4 percent of all items, confirming that small fragments numerically dominate beach litter in this region. Polymeric materials, comprising plastic and polystyrene, made up 95.7 percent of everything collected, with plastic and polystyrene contributing roughly 61 percent and 35 percent respectively within the meso-litter fraction, and about 55 percent and 38 percent within the macro-litter fraction.

The statistical analysis, based on negative binomial generalized linear mixed models that accounted for repeated visits to the same plots, site differences, and seasonal effects, uncovered a highly significant interaction between litter size class and area type. Macro-litter abundance was estimated at 1.87 items per plot in vegetated areas versus 0.87 items per plot in non-vegetated areas, an approximately 53 percent reduction in the managed sectors. Meso-litter, by contrast, showed no significant difference between area types, with predicted values of 6.61 and 7.51 items per plot respectively. A complementary binomial model confirmed the compositional consequence: the predicted proportion of meso-litter within the combined litter total was 0.90 in non-vegetated areas versus 0.77 in vegetated areas, with an odds ratio of 2.70 indicating that an individual item was far more likely to be a small fragment on managed beaches. A sensitivity analysis that included gravel-dominated plots as a third category did not alter these conclusions.

The authors are careful to note that the pattern reflects the combined influence of management and habitat conditions rather than a controlled experimental effect of cleaning alone. Vegetated and non-vegetated sectors differ not only in cleaning exposure but also in vegetation-mediated litter trapping, sediment characteristics, burial dynamics, and exposure to wind and waves. Detailed operational data such as cleaning frequency, sieve mesh size, and working depth were not available for the sites, so cleaning intensity could not be standardized. Nevertheless, the direction of the pattern matches what would be expected if mechanical cleaning preferentially removes large debris while small fragments slip through, and it is consistent with earlier work showing that fragmented plastics accumulate in coastal sediments despite routine cleaning.

The ecological implications are potentially serious. Small plastic particles are more readily ingested by marine organisms, from planktivorous fish to seabirds, and they behave differently from large items in sediment transport and burial. A beach that scores well on a macro-litter metric may therefore still host a dense reservoir of ingestible fragments. The authors argue that monitoring programs should incorporate meso-litter alongside macro-litter to avoid underestimating contamination, particularly on managed beaches where the size structure of litter has been shifted toward smaller fractions. Within the regional context, the litter densities recorded here fall within the moderate range reported for Adriatic coastal systems, and the overwhelming dominance of plastic and polystyrene mirrors patterns documented across the Mediterranean. As plastic production continues and existing debris fragments over time, the study suggests that the cleanest-looking beaches may, in a statistical sense, be among the most subtly contaminated, and that what we cannot easily see on the sand may matter most for what ends up in the food web.

Subject of Research: The effect of beach management and habitat type on the size structure of macro- and meso-litter accumulation on northwestern Adriatic beaches

Article Title: Contrasting macro- and meso-litter accumulation in managed and unmanaged beach sectors of the northwestern Adriatic Sea

Article References: Passetti, J. P., Varricchione, M., de Francesco, M. C., Carranza, M. L., Penna, A., & Casabianca, S. (2026). Contrasting macro- and meso-litter accumulation in managed and unmanaged beach sectors of the northwestern Adriatic Sea. Environmental Monitoring and Assessment, 198(11), Article 1150. https://doi.org/10.1007/s10661-026-16011-8

Image Credits: AI Generated

DOI: 10.1007/s10661-026-16011-8

Keywords: marine litter, beach management, meso-litter, macro-litter, plastic debris, Adriatic Sea, coastal dunes, monitoring protocols, MSFD, plastic fragmentation, coastal monitoring, Mediterranean

Coastal dunes are among the most threatened ecosystems on Earth, squeezed between rising seas, intensifying erosion, tourism, and urban expansion. What makes them ecologically remarkable is their strict spatial order. Moving inland from the waterline, plants sort themselves into zones: an unfixed zone of shifting sand nearest the shore, a semi-fixed zone behind it, and finally a fixed zone of stabilized dune where the most sensitive species live. Because each zone depends on precise gradients of salt spray, sand movement, wind, and soil conditions, the fixed zone is the first casualty of development and the hardest to restore. Its loss ripples through the entire system, taking rare plants with it.

The research team, led by Yuki Yamanaka, Keiko Nagashima, and Yasutaka Nakata, focused on Juniperus conferta, a low-growing shrubby juniper that serves as the classic indicator species of the fixed dune zone across Hokkaido, Honshu, Shikoku, Kyushu, and Sakhalin. The species is listed as rare in ten Japanese prefectures and grows alongside threatened plants such as Viola grayi and Veronica ornata. The logic of the study is elegant: if you can map precisely where J. conferta survives and characterize the microtopographic conditions it requires, you gain a practical yardstick for identifying the remaining strongholds of the fixed zone, and by extension, the habitats of the rare species that depend on it.

The historical half of the analysis is sobering. Using an 1898 topographic map, United States military aerial photographs from 1947, and a 2009 aerial survey, the researchers built land-cover maps for three time slices and tracked what happened to the original dune surface. In 1898, sand dunes covered roughly 192 hectares, the largest dune area in Kyoto Prefecture. By 1947 that figure had fallen to about 106 hectares, and by 2009 only about 33 hectares remained, a decline of more than 80 percent in little over a century. Afforestation, which began in the Edo period to control drifting sand and accelerated during Japan’s postwar economic boom, accounted for roughly half of the original dune area by 2009, while urbanization and paddy fields consumed much of the rest.

The losses were strikingly uneven across the dune’s four sectors. In the west, the dune shrank to about a fifth of its original extent as forests and town expanded inland. The west-central sector suffered the steepest transformation, with approximately 80 percent of its 1898 dunes replaced by conifer plantations. The east fared worst of all: around 90 percent of its original sand dunes had been converted to other land uses by 2009, with wastelands mapped in 1947 largely becoming urban areas. Only the east-central sector, a rocky coastline where steep cliffs limited development, retained nearly all of its original sandy habitat, a quirk of geology that would prove decisive for the study’s rarest plants.

To capture the present-day physical template of the dune, the team deployed a drone equipped with LiDAR, a laser instrument that fires pulses at the ground and records the returning light to build a dense three-dimensional point cloud. From this they derived a digital terrain model at one-meter resolution, matching the scale of their vegetation quadrats, along with slope angle, curvature, distance from the shoreline, and elevation. Crucially, they also computed the difference between the 2024 drone-derived terrain model and a 2009 airborne LiDAR dataset, producing a map of elevation change across fifteen years. After correcting a systematic vertical offset of about 3.46 meters in the drone data using fifty stable reference points, they established a conservative detection limit of roughly 0.12 meters, meaning only elevation changes beyond that threshold were treated as real.

On the ground, the researchers surveyed 165 one-square-meter quadrats distributed randomly across the four sectors and classified the vegetation into seven communities using the Two-Way Indicator Species Analysis, a standard clustering technique for presence-absence data. The J. conferta community split into two ecologically distinct groups: one on sandy beach coasts and one on rocky coasts. In total, the surveys recorded 30 coastal dune species and 40 non-coastal species, including eight listed in the Kyoto Prefecture Red Data Book. The east-central rocky sector stood out with the highest species richness at 47 species and five rare species, while the heavily modified west sector contained no rare species at all and a relatively high proportion of alien plants.

The statistical core of the study used generalized linear models to ask which topographic variables best predict where each J. conferta community occurs. For the sandy-beach community, two factors emerged consistently: the probability of occurrence rose with increasing distance from the shoreline and with greater elevation change since 2009. This makes intuitive sense. The community’s stronghold in the west-central sector is the one place where the beach is wide enough, over 100 meters, for the full sequence of dune zones to develop, allowing pioneer communities to trap drifting sand and build the stable backshore that dwarf juniper shrubland requires. The rocky-coast community told a different story: models pointed toward shorter distances from the shoreline and higher elevation, but a sensitivity analysis accounting for spatial autocorrelation in the data weakened these effects, suggesting the pattern may reflect broader geomorphic processes, such as a history of coastal erosion, rather than simple topographic rules.

Bringing the two lines of evidence together, the study delivers a sector-by-sector diagnosis. The west-central area, despite pine plantations, still supports functioning zonation and a resident J. conferta community, though afforestation has opened the door to invasive species. The east-central rocky coast harbors the greatest concentration of rare plants, including Viola grayi and Veronica ornata growing symbiotically with the juniper, but it is also the sector showing net elevation loss, a signature of active erosion. Because plant roots stabilize rocky slopes, the researchers warn that erosion there could accelerate, leaving the rare fixed-zone communities perched precariously at the cliff edge. The west and east sectors have effectively lost their fixed zones altogether, one to plantations and alien invasions, the other to direct human modification of the dune surface.

The authors are careful about the limits of their framework. Soil salinity, moisture, nutrients, and grain size, all known drivers of dune vegetation, were not directly measured, so the model coefficients describe associations with topography rather than isolated causes. The historical and LiDAR analyses address different time scales and should be read as complementary rather than causally linked, and the findings from a single Sea of Japan dune may not transfer to coasts with different tides, winds, and climates. Even so, the message is powerful and portable: a single well-chosen indicator species, read through the lens of drone-borne laser scanning and archival maps, can pinpoint which parts of a degraded landscape still hold conservation value and which restoration efforts are most urgent. As coastal dunes continue to retreat worldwide under the combined pressure of stabilization plantings, urban growth, and tourism, that kind of quantitative, repeatable diagnosis may be the difference between documenting an extinction and preventing one.

Subject of Research: Indicator-based assessment of coastal dune ecosystem degradation using historical land-cover change and UAV-LiDAR microtopography

Article Title: Indicator-based assessment of coastal dune ecosystem degradation using historical land-cover change and UAV-LiDAR microtopography

Article References: Yamanaka, Y., Nagashima, K., & Nakata, Y. (2026). Indicator-based assessment of coastal dune ecosystem degradation using historical land-cover change and UAV-LiDAR microtopography. Environmental and Sustainability Indicators, 32, Article 101548. https://doi.org/10.1016/j.indic.2026.101548

Image Credits: AI Generated

DOI: 10.1016/j.indic.2026.101548

Keywords: coastal dunes, Juniperus conferta, UAV-LiDAR, land-cover change, ecosystem degradation, vegetation zonation, Kumihama Dune, rare species, digital terrain model, coastal erosion, conservation indicators, Japan

The study, published in the Proceedings of the National Academy of Sciences, was led by ecologist Paul Berghuis, who is affiliated with Utrecht University and the Royal Netherlands Institute for Sea Research, known as NIOZ. Berghuis specializes in spatial ecology, a field concerned with the patterns that emerge from the interplay between organisms and their environment. His subject was the relationship between marram grass and sand, a pairing long known to be central to dune formation. Marram grass traps windblown sand around its stems, and over years the trapped sand accumulates into the embryonic dunes that eventually grow into the protective barriers shielding much of the Dutch coastline. What Berghuis set out to determine was not how a single plant builds a single dune, but how thousands of plants and dozens of dunes interlock into a coherent landscape.

To answer that question, Berghuis turned to a source of information that spans decades: aerial photographs. By analyzing these images through time, he searched for fixed patterns in the way young dune landscapes arrange themselves. The approach deliberately shifted the scale of inquiry. As Berghuis explains, quite a lot is already known about individual plants and the processes acting on them, but the deeper question concerns how the complex system of sand and vegetation fits together as a whole. That question dictated the scale at which the dunes were studied. Rather than treating the landscape as a collection of individually operating grasses and dunes, he examined it as a system that organizes itself at the landscape level. Seen that way, he found, the dune landscape displays characteristics of growth and resilience that cannot be predicted from the behavior of individual dunes or grasses alone.

The first surprise was what the patterns were not. In previously studied ecosystems that self-organize, such as mussel beds or the patchy vegetation of savannas, a regular arrangement typically emerges: spots of roughly the same size, spaced at roughly the same distances, repeating across the landscape like a biological wallpaper. Dune landscapes break that rule. Berghuis discovered that there is no fixed size to the dune bodies at all. The reason lies in the restless nature of sand. Wind moves grains again and again before they finally settle somewhere, and the places where they settle are not chosen at random. Where marram grass plants grow closely together, the sand is retained most effectively. At these high densities of vegetation, a dune continues to grow, and it often does so at the expense of its neighbors. Small dunes are left behind or disappear entirely, while larger dunes merge together into ever bigger bodies.

That behavior, in which large units grow while small ones shrink and vanish, is the signature of a well-known physical process called phase separation. Co-author Koen Siteur and other colleagues had previously argued that the spatial organization of certain ecosystems resembles this physics, and the dune findings confirm the analogy with striking precision. Phase separation is familiar from the kitchen: when oil and vinegar are shaken together to make salad dressing, the oil first disperses into countless small droplets suspended in the vinegar. Left to stand, however, the droplets coalesce. Large droplets grow at the expense of small ones, because the physics of the interface between oil and vinegar favors consolidation. The same logic, the researchers found, governs sand and marram grass. Densely vegetated dunes capture sand more efficiently, drawing it away from sparsely vegetated neighbors, so the landscape coarsens over time much as the oil in a dressing does.

Crucially, the resemblance is not merely visual. Siteur’s theory, developed in earlier work, describes how phase-separating systems can be recognized by a very specific fingerprint in their statistics, and Berghuis reports that the dunes carry exactly that fingerprint. The distribution of dune sizes, the way in which dunes merge with one another, and even the rate at which the merging slows down over time all match what the theory of phase separation predicts. This is a significant scientific advance, because it moves the field from description to explanation. As Berghuis puts it, the researchers now know not only how dunes behave but also why they do so. A landscape that once seemed to be the idiosyncratic product of local wind and plant conditions is revealed to obey a general physical law, placing coastal dunes in the same theoretical family as droplets, alloys, and other systems that separate into distinct phases.

The practical consequences of that insight are considerable, because the theory does more than describe patterns; it makes predictions about how such systems respond to disturbance. According to the theory, damage to the spatial pattern does not heal itself once it exceeds a critical threshold. In a dune landscape, this could happen when marram grass is disturbed by trampling, or when wind scours a small pit in the sand. Intuition might suggest that such wounds would gradually fill in and recover, as many ecosystems do. The theory says otherwise. The disturbances are not repaired; instead, the sand that would be needed to heal them migrates away to the more densely vegetated dunes elsewhere in the landscape, reinforcing the winners and abandoning the losers. Local damage, in other words, can become permanent even while the system as a whole appears healthy.

Berghuis’s measurements show exactly such a threshold value in the amount of marram grass present. Below a certain vegetation density, the self-repair mechanisms of the dune system fail, and degradation becomes self-perpetuating. At the same time, the theory predicts that the system as a whole remains resilient in a particular sense: the sand is not lost from the landscape but merely redistributed, flowing from damaged or sparse areas toward the densely vegetated dunes that continue to grow. This dual character, locally fragile but globally stable, is precisely the kind of behavior that phase-separation theory is built to capture, and it fundamentally changes how coastal managers should interpret the landscapes they oversee. A dune area can look robust in aggregate while individual dunes, once pushed past their local tipping point, never recover.

For the philosophy of building with nature, these findings arrive at an opportune moment. As sea levels rise, the Netherlands and other coastal nations are betting increasingly on natural dune growth as a flexible, self-reinforcing line of defense, one that can keep pace with changing conditions in ways that fixed structures cannot. But that bet depends on knowing where the system’s limits lie. The new research supplies a quantitative answer: local damage can be permanent once vegetation density falls below a critical threshold, even if the dune area as a whole remains healthy, so management must attend to the fine-grained pattern of grass cover and sand, not merely to the total volume of the dune field. For anyone who wants to build with nature rather than against it, Berghuis argues, insights of this kind are crucial. The dunes, it turns out, have been organizing themselves all along according to rules written in physics, and learning to read those rules may determine how well the coast weathers the century ahead.

Subject of Research: Spatial self-organization and phase-separation dynamics in coastal dune formation

Article Title: Local tipping points in dune landscapes: how does a dune system organize itself?

Article References: Local tipping points in dune landscapes: how does a dune system organize itself?. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: coastal dunes, marram grass, self-organization, phase separation, spatial ecology, tipping points, coastal management, building with nature, Utrecht University, NIOZ, PNAS, sea level rise