Las plataformas de abrasión con vermétidos y algas calcáreas: un patrimonio ignorado del Mediterráneo ibérico

Las plataformas de abrasión con vermétidos y algas calcáreas forman paisajes que caracterizan el Mediterráneo cálido y meridional. En ellos, encontramos multitud de especies que se aprovechan de las condiciones singulares de estos enclaves. En nuestras costas, estos ecosistemas se encuentran en gran parte del Sureste Ibérico. Sin embargo, el grado de desconocimiento de este patrimonio es grande a pesar de ciertos esfuerzos de divulgación. En el presente artículo, se describe su estructura y su valor como indicador ecológico y paleoecológico. Se analizan los principales factores naturales que condicionan su composición y dinámica, y aquellos factores antrópicos que los alteran y que pueden suponer una amenaza. Finalmente, se informa de su régimen de protección actua

Abrasion platforms with vermetids and calcareous algae: a neglected natural heritage of the Iberian Mediterranean

Las plataformas de abrasión con vermétidos y algas calcáreas forman paisajes que caracterizan el Mediterráneo cálido y meridional. En ellos, encontramos multitud de especies que se aprovechan de las condiciones singulares de estos enclaves. En nuestras costas, estos ecosistemas se encuentran en gran parte del Sureste Ibérico. Sin embargo, el grado de desconocimiento de este patrimonio es grande a pesar de ciertos esfuerzos de divulgación. En el presente artículo, se describe su estructura y su valor como indicador ecológico y paleoecológico. Se analizan los principales factores naturales que condicionan su composición y dinámica, y aquellos factores antrópicos que los alteran y que pueden suponer una amenaza. Finalmente, se informa de su régimen de protección actual.The abrasion platforms with vermetids and red calcareous algae are characteristic of the warm southern Mediterranean and make up a noteworthy landscape. In these platforms we find a large amount of species, which take advantage of the specific conditions in these particular environments. These ecosystems are very much present on the coasts of the Iberian Southeast but they are still not well known. In this article, their structure and value as ecological and paleoecological indicators are described. The main natural drivers in determining their composition and dynamics, together with the anthropic ones, which can even threaten their existence, are analysed as well. Finally, information about their current protection status is given

Using catenas for GIS-based mapping of NW Mediterranean littoral habitats

Studies aimed at describing habitats and mapping their distributions are pivotal to implementing management plans and to effectively guide conservation measures. We developed a novel approach of data collection and entry (CAT-LIT) to establish a detailed cartography of the littoral habitats found along the Catalan coast (Spain). Field data were recorded using coded, two-digit hierarchical lists (e.g. Aa, Ab, etc.) of horizons found at each point along the coast, called catenas. The horizons were either dominated by species (on the rocky bottoms) or sediment types (on the beaches) and corresponded to LPRE, EUNIS and CORINE habitats. Catenas were transferred into a database and calculations about the extent of bottom types, habitats, and catenas themselves along the coast were carried out with GIS tools. In addition, habitat link richness was calculated and represented using network analysis programs. The application of CAT-LIT to the Catalan coast showed that the habitats dominated by the lichen Verrucaria amphibia and the flattened barnacle Euraphia depressa and those dominated by the barnacle Chthamalus spp. were almost ubiquitous. Those dominated by the red alga Corallina elongata, the mussel Mytilus galloprovincialis and the red alga Rissoella verruculosa were also common. Because of the frequency of their connections, those habitats formed a huge hub of links in the networks. By using catenas, the habitats can be viewed using GIS based programs keeping the catena as the main informational and ecological unit. The catenas allow maximum compactness when vertically distributed habitats are to be shown on a 2D map. The complete cartography and dataset on the spatial distribution of the littoral habitats from Catalonia is valuable for coastal management and conservation to study changes in the habitat distribution and relate such changes to anthropogenic pressures. Furthermore, the CAT-LIT can be easily adapted to shores of other seas and oceans to obtain accurate cartographies of the spatially-reduced and highly vulnerable littoral habitats.Financial support came from the projects “Cartografia dels Hàbitats Litorals a Catalunya” (Departament de Territori i Sosteniblitat and Institut Cartogràfic, Generalitat de Catalunya) and INTRAMURAL CSIC 201330E065. This study is also a contribution of GRACCIE (C5D2007-00067) and CoCoNET (FP7 Grant Agreement: 287844) projects

On the Presence and Ubiquity of the Exotic Batophora (J. Agardh) in the Mar Menor Lagoon (SE Spain)

We first report the presence of a species of the genus Batophora in the Iberian Peninsula, in the Mar Menor lagoon (Murcia, SE Spain). We detected this macroalga in November 2021. However, according to some observations, it could have been present in the lagoon at least since 2016, being described as a “rare” form of Dasycladus vermicularis. A further survey made during May 2022 confirmed the presence of this species in much of the perimeter of the Mar Menor. Morphologic analyses are not conclusive regarding the species description, but most traits point to Batophora occidentalis or Batophora occidentalis var. largoensis. A consensus sequence from the rbcL barcode gene was compared by the Blastn tool showing its closeness to other Batophora specimens, yet the specific level was unresolved. The recent confirmation of a Batophora species in a littoral lagoon from Formentera (Balearic Islands) with similar morphologic characteristics could indicate that both putative introductions are connected. Further morphologic and genetic analyses are required in order to know the origin and expansion of this genus along the Mediterranean coasts

El estado ecológico de las plataformas de vermétidos afecta la cobertura de la especie exótica Caulerpa cylindracea

The seaweed Caulerpa cylindracea Sonder is one of the most important invaders on Mediterranean rocky shores. However, many driving pressures affecting its spread are poorly understood and seem to involve the interactions between abiotic and biotic factors. We studied the invasiveness of C. cylindracea on two shallow vermetid platforms with a contrasting ecological status on which C. cylindracea was first detected simultaneously 15 years ago. The cover values of C. cylindracea and the other macroalgal species were assessed for one year, embracing the whole platform width. Caulerpa cylindracea cover was higher on the platform that had a low ecological status, especially during warmer months at the outer seaward margin. The ecological status of the overstory of native species seems to be a key point conditioning the success of C. cylindracea invasiveness on these platforms.El alga Caulerpa cylindracea Sonder es una de las principales especies invasoras de las costas rocosas mediterráneas. Sin embargo, muchos condicionantes que afectan su proliferación son poco conocidos y parecen ser el resultado de la interacción entre factores bióticos y abióticos. Estudiamos la invasividad de C. cylindracea en dos plataformas de vermétidos que presentan un estado ecológico contrastado y en las que se detectó simultáneamente C. cylindracea hace 15 años. Los valores de cobertura de C. cylindracea y del resto de macroalgas fueron evaluados durante un año abarcando toda la anchura de la plataforma. La cobertura de C. cylindracea fue mayor en la plataforma que presentaba un pobre estado ecológico, especialmente durante los meses cálidos y en el margen externo y más expuesto de la plataforma. El estado ecológico del dosel, formado por las especies nativas, parece un condicionante clave en el éxito de la invasividad de C. cylindracea en estas plataformas de vermétidos.This work was partially funded by the project GRE14-19 of the University of Alicante

Vertical zonation is the main distribution pattern of littoral assemblages on rocky shores at a regional scale

Vertical variation in the distribution of rocky shore assemblages is greater than horizontal variation, as shown by univariate and multivariate analysis performed with data obtained along 1000 km of shoreline and covering from the upper supralittoral to the upper infralittoral zone (−1 m). Consequently, vertical littoral zonation is a consistent pattern at a regional scale within the same biogeographical zone. While their distribution varies at the same shore height, marine species and assemblages from rocky shores show a specific vertical sequence known as zonation. A key question in ecology is how consistent is zonation along large spatial scales. The aim of this study is to show distribution patterns of littoral assemblages at a regional scale and to identify the most relevant abiotic factors associated to such patterns. The study is based on a detailed and extensive survey at a regional scale on a tideless rocky shore. Benthic macroflora and macrofauna of 750 relevés were described along the vertical axis of 143 transects distributed across the shoreline of Catalonia (NW Mediterranean). The Detrended Correspondence Analysis (DCA) first axis is highly related to the height on the shore: species, relevés, and assemblages grade from lower to upper height (infralittoral to supralittoral). As observed in nature, different assemblages co-occur at the same height at different sites, which is shown along DCA second axis. The abiotic variables that best explain the assemblage distribution patterns are: height (75% of the model inertia), longitude (14.6%), latitude (7.2%) and transect slope (2.9%). The Canonical Correspondence Analysis (CCA) first axis is related to height on the shore and explains four times more variance than CCA second axis, which is related to the horizontal gradient. Generalized Lineal Model (GLM) results show that height on the shore is the factor explaining most of the variance in species presence. Most studied species show distribution patterns related to latitude and longitude, but always in a much smaller proportion than to height.Financial support for this work was provided by projects “Cartography of the littoral habitats of Catalonia” (Departament de Medi Ambient & Institut Cartogràfic, Generalitat de Catalunya), GRACCIE (C5D2007-00067), CoCoNET (FP7 Grant Agreement: 287844) and INTRAMURAL CSIC 201330E065

Estructura de los hábitats y patrones de zonación en playas del Mediterráneo noroccidental

We studied the habitat structure (macrofaunal assemblages and bottom types) and zonation patterns of 29 unvegetated shoreline strands along the 900-km coast of Catalonia (NW Mediterranean Sea). Organisms were sampled with grabs, pitfall traps, sticky traps, clam nets and spades to ensure capture of the different proportions of macrofaunal assemblages from the supra-, medio- and infralittoral levels. We collected 211 taxa: 194 animals and 17 algae. The most abundant and dominant organisms collected with van Veen grabs were Nematoda, Oligochaeta and Collembola at the supralittoral level; the polychaetes Saccocirrus spp. and Pisione remota, the amphipod Corophium orientale, Nematoda, and Turbellaria at the mediolittoral level; and Nematoda at the upper infralittoral level. SIMPER analysis revealed great dissimilarity between the organisms inhabiting the supralittoral and the other littoral levels. Regarding the epifauna, the sticky traps used at the supralittoral level mainly collected Collembola, which were nearly absent in pitfall traps. The qualitative study performed with a clam net and a small spade revealed that Nematoda, Saccocirrus spp., Turbellaria, Nemertea and the polychaete P. remota were the most abundant animals at both the medio- and the infralittoral levels and no differences were found between these levels. Different qualitative sampling methodologies showed that in fine sediments the bivalves Donax trunculus and D. semistriatus determined more than 97% of dissimilarity from coarse-sand sites. Richness increased in protected sandy and cobble shores. Littoral level and bottom-type features were only to a certain extent valid indicators of specific biotic components for a specific habitat.Se ha estudiado la estructura de los hábitats (comunidades de macrofauna y tipos de sedimento) y los patrones de zonación de 29 playas desprovistas de vegetación a lo largo de los 900 km de la costa de Cataluña (Mediterráneo noroccidental). El muestreo de los organismos se realizó mediante dragas, trampas de caída, trampas adhesivas, redes de marisqueo y palas para asegurar una captura exhaustiva de los organismos presentes en las comunidades de macrofauna de los niveles supralitoral, mediolitoral e infralitoral. Se colectaron 211 taxones: 194 animales y 17 algas. Los organismos más abundantes y dominantes recolectados con dragas van Veen fueron: Nematodos, Oligoquetos y Colémbolos en el nivel supralitoral; los poliquetos Saccocirrus spp. y Pisione remota, el anfípodo Corophium orientale, Nematodos y Turbelarios en el nivel mediolitoral; y Nematodos en la parte menos profunda del nivel infralitoral. Los análisis SIMPER detectaron grandes diferencias entre los organismos del nivel supralitoral y los de los otros niveles. Respecto a la epifauna, las trampas adhesivas usadas en el nivel supralitoral capturaron principalmente Colémbolos, los cuales estaban ausentes en las trampas de caida. El estudio cualitativo realizado con una red de marisqueo y una pala pequeña reveló que Nematodos, los poliquetos Saccocirrus spp. y Pisione remota, Turbelarios y Nemertinos eran los animales más abundantes tanto en el nivel mediolitoral como en el nivel infralitoral y que no había diferencias entre ambos niveles. Diferentes métodos cualitativos de muestreo revelaron que en los sedimentos finos los bivalvos Donax trunculus y D. semistriatus determinaban más del 97% de la disimilitud con los sedimentos gruesos. La riqueza en especies aumentaba en playas mixtas de arenas y cantos. El nivel y el tipo de sedimento fueron solo hasta cierto punto indicadores válidos de la composición de especies para cada hábitat concreto.Financial support came from the projects “Cartografia dels Hàbitats Litorals a Catalunya” (Departament de Territori i Sosteniblitat and Institut Cartogràfic, Generalitat de Catalunya) and INTRAMURAL CSIC 201330E065

Multidisciplinary Analysis of Cystoseira sensu lato (SE Spain) Suggest a Complex Colonization of the Mediterranean

Cystoseira sensu lato (sl) are three genera widely recognized as bioindicators for their restricted habitat in a sub-coastal zone with low tolerance to pollution. Their ecological, morphological and taxonomic features are still little known due to their singular characteristics. We studied seven species of Cystoseira sl spp. in Cabo de las Huertas (Alicante, SE Spain) and analyzed their distribution using Permutational Analysis of Variance (PERMANOVA) and Principal Component Ordination plots (PCO). A morphological cladogram has been constructed using fifteen phenotypic taxonomic relevant characters. We have also developed an optimized Cystoseira sl DNA extraction protocol. We have tested it to obtain amplicons from mt23S, tRNA-Lys and psbA genes. With these sequence data, we have built a phylogenetic supertree avoiding threatened Cystoseira sl species. Cartography and distribution analysis show that the response to hydrodynamism predicts perennial or seasonal behaviors. Morphological cladogram detects inter-specifical variability between our species and reference studies. Our DNA phylogenetic tree supports actual classification, including for the first-time Treptacantha sauvageauana and Treptacantha algeriensis species. These data support a complex distribution and speciation of Cystoseira sl spp. in the Mediterranean, perhaps involving Atlantic clades. The high ecological value of our area of study merits a future protection status as a Special Conservation Area.This research received partial funding from the Botany section (36502G0001) of the Department of Marine Science and Applied Biology, the University of Alicante

Associated Benthic Fauna to the Vermetid Reefs along the Mediterranean Spanish Coast

The aim of this study was to investigate the benthic fauna associated to nearshore vermetid reefs. Sampling was conducted along the Mediterranean coast of Spain, in three different areas, using scraping techniques, to characterize the taxonomic assemblage living among and inside the Dendropoma empty shells. The results showed high abundance and very low taxa diversity

The dynamics of phytobenthos and its main drivers on abrasion platforms with vermetids (Alicante, Southeastern Iberian Peninsula)

Abrasion platforms with vermetids shape unique seascapes and biotic assemblages that characterize several of the warm Mediterranean coasts. The composition, structural and seasonal dynamics of the platforms’ phytobenthos were examined at two Southeast Iberian locations through non-destructive sampling. The patterns observed were linked with environmental variables and grazers’ coverage, and we assessed their possible influence. Structural descriptors α-diversity and β-diversity were applied, pointing that depth and season-related variables were the major influencing drivers. Higher α-diversity and β-diversity values during winter and spring coincided with the production optimum of the community. A greater average water depth influences the abundance of both midlittoral and infralittoral taxa. The strong resemblance between the phytobenthos of these vermetid platforms and that on similar platforms in the Eastern and Central Mediterranean Sea suggests that these are affected by the same structuring mechanisms.This research received financial assistance from the project “Seguimiento de macroalgas sobre el litoral rocoso y Posidonia de la Comunidad Valenciana, dentro de la Directiva Marco del Agua” of the Generalitat Valenciana