60f Palacín Cabañas, Cruz [WorldCat Identities]
WorldCat Identities

Palacín Cabañas, Cruz

Overview
Works: 25 works in 32 publications in 3 languages and 33 library holdings
Roles: Other, Author
Publication Timeline
.
Most widely held works by Cruz Palacín Cabañas
Spatio-temporal patterns of genetic variation in Arbacia lixula, a thermophilous sea urchin in expansion in the Mediterranean by Rocío Pérez-Portela( )

1 edition published in 2018 in English and held by 2 WorldCat member libraries worldwide

Chemical and microbial ecology of the demosponge Aplysina aerophoba by Oriol Sacristán Soriano( Book )

2 editions published between 2013 and 2014 in English and held by 2 WorldCat member libraries worldwide

Phylum Porifera (Grant, 1836) are sessile metazoans with a differentiated inhalant and exhalant aquiferous system with external pores. Lacking a tissue grade of construction, sponges can reach two well-differentiated regions, the ectosome (external layer free of choanocytes) and the choanosome (internal region with choanocytes). As the most likely primitive metazoans, their challenging structural organization, physiology for biocalcification and trophic requirements allowed sponges to rapidly colonize distinct environments and built important sponge reefs during the Paleozoic and Mesozoic eras, making them an ecologically relevant group principally in marine benthic communities. To date, sponges are still ecologically important among benthic fauna although the role as reef builders in modern coral reefs has changed in favor of scleractinian corals. Nonetheless, sponges have demonstrated a huge capacity to adapt and spread in many habitats contributing to organization and functioning at both community and ecosystem levels. One of the keys of the evolutionary success of this group lies in the close association between sponges and microbes that dates back to the Precambrian era. The need to be defended may have arisen from the lack of motility of sponges and several mechanisms emerged to fulfill their demand including a chemical protection. Many sponges would have taken advantage of associated microbes to use their metabolites as a defense barrier against predators, competitors or foulers. This particular symbiosis has consequently become a key factor in biotic interactions within the sponge research. To date, chemical ecology and microbial ecology are two independent areas of the sponge research with ecological implications that occasionally converge at the same point. We want to analyze the evolution of the sponge chemical and microbial ecology from the very beginning, to quantify their impact on the scientific community, and to compare both research areas. This PhD dissertation has been conceived to study the chemical and microbial ecology of sponges using the demosponge Aplysina aerophoba (Nardo, 1833) as a model species because its secondary chemistry and its associated microbial community are well studied and it is quite abundant in our study area (Northwestern Mediterranean and Canary Islands). Beyond the knowledge achieved about the major chemistry and bacterial assemblages in A. aerophoba, we have been able to explore the variation sources of the natural products and the sponge microbial consortium. Additionally, we have assessed the putative relationships between the host bacterial community and the production of secondary metabolites in this species. We explored changes in the abundance of secondary metabolites and the relative composition of bacterial assemblages in A. aerophoba at multiple spatial (from few centimeters to thousand kilometers) and temporal (months and years) scales. The approach used allowed us to investigate which is the magnitude of the variance attributable to the distinct spatial and temporal scales and the most relevant scale at which the abundance of secondary metabolites and bacterial symbionts varied. We also investigated the relationship between natural products and microbial community structure by assessing whether both parameters covary at multiple scales. Finally, we experimentally addressed whether different light exposures can modify chemical and microbial profiles in the external and internal regions of A. aerophoba. In summary, the production of natural products in sponges and the abundance and phylogenetic composition of the host-associated microbial community mainly depend to a large extent on the sponge-species and the ecological factors with spatial and temporal variations (e.g., light, predation, competition, fouling). The host state (i.e., stress) is also a key factor that may be the main driver of symbiotic shifts causing a breakdown in the sponge health and making the symbiont communities unstable and likely the sponge chemical defense. The combination between abiotic and biotic factors may finally determine the concentration of bioactive compounds and associated microbial diversity as the abiotic environmental context can control the outcomes of biotic interactions, and biotic interactions often moderate the effect of abiotic factors. For that reason, it is not an easy task to actually figure out the factors that limit or enhance chemical and microbial variability. Further experiments and time-series observations are needed to reveal the underlying processes hidden
Estudio ecológico de la meiofauna bentónica de la Bahía de Els Alfacs (Delta del Ebro) : ecología y sistemática de las poblaciones de nematodos by Cruz Palacín Cabañas( Book )

2 editions published in 1990 in Spanish and held by 2 WorldCat member libraries worldwide

Biology and phylogeography of the black sea urchin Arbacia lixula (Echinoidea: Arbacioida) = Biología y filogeografía del erizo de mar negro Arbacia lixula (Echinoidea: Arbacioida) by Owen S Wangensteen Fuentes( Book )

2 editions published in 2013 in English and held by 2 WorldCat member libraries worldwide

Hope springs eternal in the starfish gonad: preserved potential for sexual reproduction in a single-clone population of a fissiparous starfish by Alex Garcia-Cisneros( )

1 edition published in 2016 in English and held by 2 WorldCat member libraries worldwide

Patterns of genetic and morphologic diversity in Antarctic sponges = Modelos de diversidad genética y morfológicas en las esponjas antárcticas by Mirco Carella( )

2 editions published in 2018 in English and held by 2 WorldCat member libraries worldwide

The Antarctic bottoms harbour rich communities of sponges, which play an important role in structuring benthic habitats. Many Antarctic sponge species have been discovered in the past but most of them were poorly described or incorrectly ascribed to species or genera. Thus, the biodiversity this area is still incompletely explored. However, in the last 20 years the taxonomic and ecological studies of marine benthic invertebrates have benefited from the use of molecular tools, such a mitochondrial and nuclear markers or species-specific markers obtained from sequencing a part of the sponge genome. The present thesis contributed to improve the systematic of an Antarctic sponge group and its phylogenetic relationships with other members of the family (Tetillidae) spread all over the world, and to assess the asexual reproduction rate of an Antarctic sponge species (Stylocordyla chupachups). The phylogeny of Tetillidae has been previously approached using several nuclear and mitochondrial markers but including an incomplete number of Antarctic species. This study, did not resolve completely the family phylogeny and lacked a deep morphological revision of the species sequenced. Hence, in this thesis we performed a new phylogenetic analysis of the family by adding more Antarctic specimens and additional mitochondrial and nuclear markers. Moreover, the morphological characters plus the secondary structure of the (V4) region of the 18S rDNA were analyzed under the principle of maximum parsimony. The resulting trees retrieved seven monophyletic well-supported clades in both the molecular and morphological phylogenies, which correspond to the genera: Cinachyra, Acanthotetilla, Tetilla, Cinachyrella, Craniella, Antarctotetilla and Levantiniella. However, the mitochondrial and nuclear markers used were very conserved and could not discriminate Antarctic species of their corresponding genera (Antarctotetilla and Cinachyra). The revision of the species type of Tethya coactifera and Tethya crassispicula with the COI minibarcode sequence (useful for sequences with degraded DNA) confirmed that these two species were within the Antarctic clade, but the minibarcode was not informative at genus or species levels. Antarctotetilla and Levantiniella are described for the first time in this thesis. The main diagnostic traits of these genera are: pores grouped in small surface depressions and a slight cortical region (pseudocortex) in Antarctotetilla, and small surface cavities that resemble porocalices in Levantiniella. A detailed morphological revision of the types T. coactifera and T. crassispicula, confirmed that they belong to Antarctotetilla and Cinachyra, respectively. A new Antarctotetilla species (Antarctotetilla pilosa) was also described. On the other hand, we performed a genetic study of three populations of S. chupachups, using microsatellites, to test the hypothesis of a relatively higher asexual reproduction rate in Antarctic sponges due to the Antarctic stable environment and the selection of adapted genotypes. Our analysis proved that the 25% of the populations reproduce asexually, which represents a higher rate with respect to that reported for non-Antarctic sponge species. The three populations were slightly but significantly structured, which indicates a low genetic connectivity. Heterozygote excess was found in the three study populations. Relatively elevated rates of clonal reproduction and heterozygote excess are traits rarely found in sponge species from other latitudes and can be related to the particular environmental characteristics and the evolutionary history of the Antarctic. A founder effect was found in two of the study populations, which agrees with the pioneer nature reported for the species. At first sight, low genetic diversity resulting from a high rate of clonal reproduction would suggest vulnerability of sponge populations in the Antarctic ecosystems. However, compensatory genetic mechanisms, such an ancestral selection for heterozygotes, may be acting, and together with sexual reproduction, may preserve the minimal genetic diversity in S. chupachups populations to success in the Antarctic
Mediterranean deep-sea ecosystems biodiversity, functioning and vulnerability = Ecosistemes profunds de la Mediterrània : biodiversitat, funcionament i vulnerabilitat by Samuele Tecchio( Book )

2 editions published between 2012 and 2013 in English and held by 2 WorldCat member libraries worldwide

The Mediterranean Sea can be considered an excellent natural laboratory for benthic ecologists, due to its peculiar environmental conditions, its broad-scale gradients, and its deep-sea fauna. Primary production levels in the Mediterranean follow a longitudinal gradient, decreasing from west to east. The present thesis focused on the fine-mud benthos habitat of the Mediterranean Sea, on its bathyal and abyssal zones, and the compartment considered was demersal megafauna. The main objective of the present thesis was to describe and characterize the deep habitats of the Mediterranean Sea, relating their biodiversity and ecosystem functioning with the varying environmental conditions along the geographic, bathymetric, and temporal axes. The work was divided into four parts. In the first part, the patterns of distribution, biomass and abundance of bathyal and abyssal megafauna were studied, in relation with environmental variables, along longitudinal and bathymetric gradients. This was a large geographic scale study, across the three basins of the Mediterranean at depths of 1200-3000 m. Benthic biomass strongly decreased with depth and longitude (west-to-east). Results showed a significant correlation between the dynamics of surface layers, the amount of food available on the bottom, and the composition of benthos. In the second part, the seasonal fluctuations of benthic communities in the Catalan continental margin were observed. A highly replicated, multi-period study was conducted at depths of 900-1500 m. Total biomass followed an inverted U-shaped pattern, peaking at depths of 1050-1350 m. Range-related ecological forcings between shallower and deeper species may have caused this biomass accumulation at intermediate slope depths. The arrival of a new water mass from the deep basin to the slope in spring may have also driven an accumulation of biomass at 900-1050 m depth over the same period. An adjacent submarine canyon was also studied, comparing communities between the canyon and the open slope area. Analyses revealed higher diversity, but not biomass, inside the canyon than in the adjacent open slope, and a significantly different assemblage between the habitats. These results strengthen the concept of submarine canyons as hotspots of biodiversity and underline the importance of their conservation as diversity repositories. The third part is a study on trophic relations of deep-sea fauna, over the same large spatial transects considered in the first part, by means of natural-abundances stable isotopes analyses and the use of novel statistical methods to analyse heavy datasets all in once. Bulk-tissue d13C and d15N isotope ratios were analysed for benthic megafauna and associated surface and mesopelagic components from the 3 basins of the Mediterranean Sea. The trophic niche width and the amplitude of primary carbon sources were positively correlated with both primary and secondary surface production indicators. Moreover, mesopelagic organic matter utilization processes showed an intermediate position between surface and deep benthic components. Thus, both primary and secondary production processes taking place at surface layers are key drivers of deep-sea food web structuring. Finally, the fourth part integrates the whole collected dataset into the first ecotrophic model of a deep-water ecosystem in the Mediterranean Sea, evaluating the general ecosystem functioning as well as the degree of vulnerability of these ecosystems. The Ecopath with Ecosim approach was used to model the flows and biomasses of the Catalan Sea continental slope ecosystem at depths of 1000-1400 m. Network analysis identified low levels of consumer biomass cycling and low system omnivory index when compared with expected values of marine ecosystems, and higher cycling and omnivory when compared with available models of shallower areas of the Mediterranean. A simulation of the possible expansion of the red-shrimp benthic trawl fishery that currently operates at shallower depths, showed reductions in fish biomass and that the state of the deep continental slope ecosystem seems to be result of a long-term succession process, which has reached ecological stability, and is particularly vulnerable to human impact and, specifically, to fisheries exploitation
Morphological structure and biodiversity in fish assemblages by Marc Farré Foix( )

2 editions published in 2016 in English and held by 2 WorldCat member libraries worldwide

The study of morphology of organisms has become a widely extended scientific discipline since the beginning of the 20th century, when the scientific community began to establish direct relationships between the anatomical characteristics of organisms and their adaptations and biological strategies. The study of morphological variability allowed determining and understanding the ecological and functional roles of species within the ecosystems where they inhabit. According to this ecomorphological current, ecologists promptly perceived that morphology of species were essential to address many aspects traditionally of their interest that were essential to understand the functioning and organization of communities, such as the resource partitioning or the habitat differentiation. Following these premises, the overall objective of this thesis was to determine and describe the morphological diversity of several fish assemblages, in order to highlight the importance of the study of the morphology of species as an alternative and complementary useful tool in biodiversity and community structure studies. To test the hypotheses and reach the purposes, several fish assemblages with different geographical, environmental, ecological and hydrological conditions were analysed: from mesopelagic fish assemblages from the Canary Islands (NE Atlantic ocean) to coastal fish assemblages along the Catalan coast or demersal fish assemblages along a wide bathymetric range along the continental shelf and slope of the Balearic Islands (NW Mediterranean Sea). The morphological analysis included the overall body shape and the shape and position of fins and sensory organs, and was performed using landmark-based geometric morphometric methods (GM). These analyses are widely used for quantifying and analysing the shape variation between structures, since they allow to describe the geometric characteristics of the structures easily, quickly and with higher level of detail; they conserve the geometric traits of objects along all the procedure and they possess a powerful associated statistical support. Besides, the application of GM also allows the computation of measures of morphological diversity. Thus, another objective of this thesis was to develop new morphological diversity indices from GM methods and describe their correlations with other biodiversity components traditionally more considered (ecological, taxonomical and functional diversity) in order to demonstrate the validity and provide and additional approach that helps to complement studies of biodiversity of fish assemblages. The morphological structures (morphospaces) and the biodiversity indices were obtained for all the analysed fish assemblages and were compared to assess the ability of the morphological methods in order to describe the structure and organization of fish communities. The results demonstrated that the computed morphological diversity indices correlated significantly with the other biodiversity components, were useful for biodiversity studies since they provide information about the functioning and structure of communities (especially when ecological or functional traits of species and ecosystems are absent or scarce, which can be very common), and in addition they yielded equivalent results when they were computed using quantitative (abundance) and qualitative (presence/absence) data. Besides, the analysis of the morphospaces of the different communities allowed to infer and understand key aspects about the functioning and organization of communities, such as the resource partitioning, the habitat differentiation or interspecific relationships such as coexistence, competence or dominance. Therefore, the general results of the present thesis reinforces and support the hypothesis that the morphology of species is a good tool addressing the ecological and functional roles of species within ecosystems, and that the assessment of the morphological variability among species contributes to better understanding the structure, organization and functioning of communities
Estructura, distribución e historia evolutiva de las poblaciones de estrellas de mar Echinaster sepositus y Coscinasterias tenuispina by Álex García Cisneros( )

2 editions published in 2016 in Spanish and English and held by 2 WorldCat member libraries worldwide

El conocimiento de la filogeografía, la estructura y la diversidad genética de las poblaciones es importante para entender y evaluar la situación de las diferentes especies, detectar su posible vulnerabilidad y desarrollar estrategias para su gestión. En el Mediterráneo hay un total de 154 especies de equinodermos y, de las cuales 33 son asteroideos. A pesar de tratarse de un grupo muy conocido, hay pocos estudios de filogeografía o genética de poblaciones de estrellas de mar realizados en el Mediterráneo. En esta tesis doctoral se estudian dos especies de asteroideos atlanto-mediterráneos, Echinaster sepositus y Coscinasterias tenuispina, dos estrellas muy comunes en el litoral rocoso mediterráneo Ambas especies tienen estrategias vitales diferentes, pero distribuciones geográficas parecidas, y hasta ahora se desconocía su historia evolutiva y algunas de sus características biológicas. Echinaster sepositus es una estrella roja, vistosa y que puede llegar a ser muy común en algunas áreas. Se encuentra en el Mediterráneo y áreas templadas del Atlántico. E. sepositus se reproduce únicamente de forma sexual; el resultado de la fecundación es una larva lecitotrófica, que no se alimenta durante su vida planctónica, que en la mayoría de los casos, no supera una semana. Coscinasterias tenuispina es una estrella espinosa de talla mediana y coloración variable. Puede reproducirse sexual (larvas planctotróficas) y asexualmente (fisiparidad). Se caracteriza por presentar un número de brazos normalmente superior a cinco y está ampliamente distribuida en el Mediterráneo y a ambos lados del Atlántico. Para estudiar ambas estrellas de mar se han utilizado marcadores moleculares, como el gen de la citocromo oxidasa subunidad I (COI), diferentes loci microsatélite del genoma nuclear (diseñados a partir de bibliotecas de pirosecuenciación 454), y la longitud de los telómeros en individuos clonales. Además, se ha realizado el seguimiento de poblaciones de Coscinasterias tenuispina para conocer su dinámica poblacional y su ciclo biológico a lo largo del año. Los resultados de este estudio muestran que ambas especies presentan una baja diversidad genética comparada con otros equinodermos de igual distribución, aunque los motivos de esta baja diversidad son diferentes para cada una. Por un lado, la baja diversidad de Echinaster sepositus se explica por un proceso de expansión demográfica muy reciente, a partir de un número reducido de individuos con pocos alelos. En el caso de Coscinasterias tenuispina, la baja diversidad está más relacionada con su elevada clonalidad, ya que existen poblaciones exclusivamente monoclonales y también se encuentran clones en el resto de poblaciones. Estos valores de diversidad podrían dar lugar, en ambas especies, a un bajo potencial de adaptación y, por tanto, hacerlas más sensibles a cambios ambientales. De hecho, dos poblaciones de Echinaster sepositus cercanas a zonas contaminadas han mostrado una estructura genética diferente al resto de poblaciones. Se ha observado que las barreras marinas originadas por el frente Almería-Orán y por el estrecho Sículo-Tunecino actúan restringiendo el flujo genético entre las poblaciones de ambas especies, aunque permiten un cierto grado de permeabilidad e intercambio genético entre las mismas. Los procesos de asexualidad en Coscinasterias tenuispina le permiten mantener poblaciones monoclonales densas a lo largo del tiempo, así como aumentar su área de distribución. La fisiparidad parece modularse en función de la inestabilidad ambiental, tanto térmica como física. En cualquier caso, el potencial sexual de los individuos (desarrollo de gónadas, masculinas en todos los casos) se mantiene siempre y cuando la condición alimentaria sea favorable. Se ha observado también que esta estrella de mar dispone de recursos para evitar algunos de los efectos deletéreos que podrían aparecer tras sucesivas o ilimitadas generaciones generadas por fisión, como es el caso del mecanismo de alargamiento de telómeros
Silicon consumtion by marine sponges : an empirical approach and its ecological implications by María López Acosta( )

1 edition published in 2018 in English and held by 1 WorldCat member library worldwide

Mediterranean deep-sea ecosystems: biodiversity, funtioning and vulnerability = Ecosistèmes profunds de la Mediterrània: biodiversitat, funcionament i vulnerabilitat by Samuele Tecchio( Book )

1 edition published in 2012 in Catalan and held by 1 WorldCat member library worldwide

Silicon consumption by marine sponges: an empirical approach and its ecological implications by María López Acosta( )

1 edition published in 2018 in English and held by 1 WorldCat member library worldwide

Silicon (Si), in its dissolved form of silicic acid (DSi), is a key nutrient in the ocean. The availability of such nutrient in marine ecosystems is regulated through its use by silica-secreting organisms, a variety of groups including protists, algae, and animals that consume DSi to build their silica (BSi) skeletons. The interest in determining how Si cycles in the ocean is high, since it interacts with the cycling of other major nutrients and ocean primary productivity. Because diatoms are the most abundant Si users, the scientific attempts to quantify the Si utilization in the ocean have been only focused on these organisms, considering negligible the role of other Si users. Over the last decades, some studies have suggested that at least another group, the siliceous sponges, are also playing a non-negligible role in the consumption of Si in marine ecosystems. Marine sponges are conspicuous animals in benthic ecosystems. They are common across the world ocean, irrespective of the latitude and depth, being able to form enormous aggregations that may extend over large areas. Both their ubiquity and their abundance make sponges good candidates to develop relevant functional roles in marine ecosystems. Regarding the use of Si, it is surprising that, despite about 80% of the sponge species require from DSi to elaborate their skeleton, almost no information is available about how sponges consume such nutrient. In fact, before the beginning of this PhD, only few studies had investigated DSi consumption in marine sponges, with kinetic models available for only four species in two genera of demosponges. This lack of knowledge sparked this PhD, which has been developed in the frame of three research grants: 1) "A research action to quantify fluxes and sinks of silicon through sponges: a neglected circuit within the marine cycle" (MEC–CTM2012-37787); 2) "Exploring the biological production of silica and its applications in science and technology" (MINECO-CTM2015-67221- R); and 3) WP4 —Ecosystem functions, services, and goods— in the EU's project SponGES (H2020-No. 679849). The main objective of the work was to improve the general understanding on how sponges utilize DSi, to facilitate further assessment of the quantitative role of the sponges as Si users. Here we investigated the kinetics of DSi consumption in five sponge species: four temperate, shallow-water demosponges and, for the first time, a cold, deep-water hexactinellid sponge. We also examined the sources of between-species and between-individual variability in DSi consumption responses. Interestingly, we detected that DSi consumption kinetics can change seasonally in some species, what may have important implications when quantifying the role of sponges as Si users. Additionally, we determined for the first time the rate of DSi utilization by a sponge species in situ. The results significantly matched those estimated from the kinetic models obtained in the laboratory, supporting the use of long (>24h) incubations in laboratory to investigate DSi consumption kinetics in sponges, in contrast to the very short periods traditionally recommended for diatoms (< 3h). Finally, we used the empirically information gained on DSi consumption over the development of this PhD to estimate the utilization of DSi by a sponge assemblage at the ecosystem level, using as case study the bay of Brest (France). In summary, this research showed that sponges have a noticeable role as Si users, even in a shallow-water ecosystem (the bay of Brest) where diatoms largely contribute to the phytoplankton biomass. Our results also indicated that sponges increase their role in marine ecosystems with increasing availability of DSi in seawater. Thus, sponges are predicted to play a relevant role as Si users in high-latitude and deep-water habitats, characterized by high DSi availability. All together, the siliceous sponges should be considered as Si users if we aim to accurately quantify the cycling of Si in marine ecosystems
Macro- and micro -symbioses involving sponges : ecological roles in the marine benthos by Marta Turon Rodrigo( )

1 edition published in 2020 in English and held by 1 WorldCat member library worldwide

"The symbiotic lifestyle represents a fundamental contribution to the diversity of marine ecosystems. Sponges are ideal models to study symbiotic relationships from evolutionary and ecological points of view since they are the most ancient metazoans on Earth, are ubiquitous in the marine benthos, and establish complex symbiosis with both prokaryotes and animals, which in turn harbour their own bacterial communities. In this thesis, we aim to go deeper into the mechanisms by which sponges establish symbiotic associations with members of the three domains of life, combining taxonomical, ecological, and molecular approaches. We study how sponges acquire their symbiotic microbes and whether these microbes contribute to shape the ecological distribution of their hosts. Moreover, we use the sponge-polychaete relationship as an example of multi-partner symbiosis and study the eukaryotic association from the microbial perspective. Finally, we focus on the less studied domain of life, the archaea, to gain insights into the composition and stability of these symbionts in sponges.To assess these goals, we characterized the sponge assemblages in two contrasting environments (well-preserved and impacted) of Nha Trang Bay (Vietnam) and selected the most abundant species for the study of their microbiomes. Additionally, four sponge species harbouring thousands of polychaetes were sampled to analyse the relationships sponge-microbes-polychaetes. Sponges and polychaetes were identified and their respective microbiones and the seawater bacterial communities were analysed by high-throughput sequencing of the 16S rRNA gene (V4 region). We first describe and illustrate the sponges collected to facilitate further taxonomic and faunistic studies in the area. Our samples belonged to 60 species (9 orders, 22 families, and 36 genera) of demosponges. A total of 24 species were added to the already known sponge fauna of Vietnam, from which, 11 species likely represent new species to science. The described species represent an increase of 8 % in the already known sponge list of Vietnam. Our results show that sponge assemblages were more diverse and rich in the well-preserved environments, being dominated by Neofibularia sp. and Aaptos suberitoides in the reefs, and by Monanchora unguiculata, Antho (Antho) sp., and Amphimedon sulcata in rocky habitats. On the other hand, impacted coral reefs were mainly dominated by two abundant species: Clathria reinwardti and Amphimedon paraviridis.Similar ecological metrics were shown by the sponge microbiomes according to the type of habitat, being more diverse in the well-preserved environments. Morever, the sponge microbiomes of the sponge assemblages from the impacted habitats showed higher intra-species dispersion and lower core size (shared ZOTUs across species replicates) than microbiomes of sponges from the well-preserved environments. In this sense, we propose that the Anna Karenina concept, which states that intraspecific variability is higher in dysbiotic than in healthy individuals, can also be applied at the community level for the study sponge assemblages.In our study sponges, bacterial communities were highly stable regardless of the environment, whereas some of their associated polychaetes varied depending on the sampling location. Environmental resilience to different habitat conditions was certainly true for bacterial communities of A. sulcata, the solely species that was found abundant in the two contrasting habitats explored.Moreover, the high overlap in bacteria composition between sponges and seawater suggest microsymbiont acquisition from the environment. In a similar manner, polychaetes were also able to specifically select and enrich some bacteria from their food sponge. Overall, most sequences were shared between biotypes, but at differential abundances, leading to highly specific and stable invertebrate microbiomes, acquired from the environment. Our results support the tenet "Everything is everywhere, but the environment selects." -- TDX
Filogenia, genética de poblaciones y biología del género Pycnoclavella (Ascidiacea) by Rocío Pérez Portela( )

1 edition published in 2006 in Catalan and held by 1 WorldCat member library worldwide

Ecology and biodiversity of the deep-sea meiobenthos from the Blanes Canyon and its adjacent slope (NW Mediterranean) = Ecología y biodiversidad del meiobentos profundo del Cañón de Blanes y su talud adyacente (NO Mediterráneo) by Sara Román Moreno( )

1 edition published in 2017 in English and held by 1 WorldCat member library worldwide

"Submarine canyons are major topographic structures forming deep incisions in shelfs and continental margins around the globe. Due to their topographic characteristics, canyons influence both local hydrodynamic conditions and the transfers of organic material and sediment from shelfs to deep seafloor. This leads to changes in sediment characteristics and organic enrichment that play a key role in deep-sea the functioning, and particularly affect benthic communities. Metazoan meiobenthos are the most abundant deep-sea infauna, with nematodes being dominant. Due to their small size, meiofauna is intimately related with the sediment so that the physical properties are highly influencing the assemblages harbored by a given ecosystem. Therefore, habitat heterogeneity, a particularly relevant canyons feature plays a key role in shaping meiofaunal distribution and biodiversity. Blanes canyon (NW Mediterranean) has been intensively explored during the last years, mostly in relation with the fishery activities in the area. However, as in many other canyons, the meiobenthic component had been almost neglected. Within this context and in the frame of the Spanish research project Dos Mares, the present thesis, focus on the metazoan meiofauna in the Blanes Canyon system. Samples were obtained by the multicore deployments from 500 to 2,000 m depth during four oceanographic campaigns (spring and autumn in 2012-2013). The main objective was to increase the knowledge and further understanding of the patterns and trends of meiofaunal density, diversity and community composition, as well as on its main environmental drivers, with a particular emphasis on the dominant nematode assemblages. Our results indicate that Blanes Canyon exhibits: marked sediment variability, high food availability (i.e., Organic Carbon, Chlorophyll a, Chloroplastic Pigments Equivalents) compared to the adjacent slope, together with higher density, and diversity, and more marked differences in community composition and distribution, both at higher (i.e., meiofauna) and lower (i.e., nematodes and kinorhynchs) taxon level. The observed temporal variability is only partly explained by the seasonal patterns of food input, derived from phytoplanctonic production, where major oceanographic processes such as recurrent dense shelf water cascading events; seem to play a key role. Moreover, the topographically heterogeneous environment associated to the canyon bathymetric gradient, combined with the existence of recurrent, non-seasonal food pulses, are better explaining the observed meiofaunal trends, particularly those concerning nematodes. However, among all gradients analysed, the greatest effect on nematode communities occurred at small-scale (cm), both in the canyon and on the slope, with the highest abundance at the surface sediment layer leading to a marked diversity decrease along the vertical sediment profile. This Thesis includes the first known study on Mediterranean deep-sea kinorhynchs, which contributes to increase the current knowledge on its diversity and distribution, as seven over the nine species found in the canyon system turned to be undescribed. Our results allowed us to avoid suggesting generalizations in the description of meiofauna patterns in the canyon, highlighting those different taxa may show different bathymetric-related responses, this being particularly relevant in the case of the rare taxa (e.g., the kinorhynchs). They also support the consideration of submarine canyons as hotspots of faunal density, biomass and diversity, confirming its key role in shaping the patterns and trends shown by benthic fauna. Finally, the overall results of this Thesis strongly suggest that the Blanes Canyon system is not functioning as a purely natural environment. The high sedimentation rates in the canyon axis suggest that the indirect but regular effects of bottom trawling are driving the structure, and possibly the functioning, of the associated meiobenthos, all along the axis down to at least, 1,750 m depth." -- TDX
Historia de vida temprana e inversión reproductiva de invertebrados bentónicos: integración al manejo y conservación a través de modelos de dispersión = Early life and reproductive investment of benthic invertebrates: integration to management and conservation throught dispersal models by Marta Blanco Sánchez( )

1 edition published in 2019 in Spanish and held by 1 WorldCat member library worldwide

"Las zonas costeras son uno de los ecosistemas que sufre mayor impacto antrópico a nivel mundial. La sobreexplotación de los recursos marinos es una de las actividades humanas que genera mayor impacto, reduciendo la abundancia y tamaño de las especies objetivo. Una de las medidas para proteger estos ecosistemas consiste en el establecimiento de áreas marinas protegidas. En Chile, el sistema actual de manejo de las pesquerías artesanales de especies bentónicas está basado en áreas parcialmente protegidas, las Áreas de Manejo y Explotación de Recursos Bentónicos (AMERBs), lo que ha supuesto una mejora en la sostenibilidad de una actividad de larga tradición en el país. Estas áreas entregan derechos de usos territoriales, conocidos mundialmente como TURF (sigla en inglés de Territorial Use Right for Fisheries). Sin embargo, actualmente estas áreas se gestionan de forma individualizada, de tal manera que la escala espacial de manejo no está acoplada a la escala de la dinámica de las poblaciones de invertebrados bentónicos. El objetivo de esta tesis es identificar áreas de alto valor para la producción, exportación y llegada de larvas en base a los patrones de historia de vida temprana, considerando variables y/o condicionantes relevantes de la fase adulta bentónica, como (a) la inversión reproductiva, (b) la densidad y talla de los adultos reproductores, variables determinantes de la distribución espacial de la producción de huevos y larvas, así como también variables que intervienen en la fase larval planctónica, como (c) los rasgos biológicos larvales, para acoplarlo con los patrones de circulación costera con el fin de contribuir a un mejor entendimiento de la dispersión y conectividad larval. Para este fin se seleccionaron dos especies relevantes social, comercial y ecológicamente: el erizo rojo (Loxechinus albus) y la lapa (Fissurella latimarginata). En primer lugar, se evaluó mediante muestreos de campo el efecto de la protección (relacionada con el régimen de explotación) y afloramiento costero sobre la inversión reproductiva y la condición individual de los adultos reproductores. Esta información sumada a los datos empíricos de distribución de tallas, densidad de individuos y fecundidad de las hembras reproductoras se utilizó para desarrollar un modelo de producción potencial de huevos en la costa central de Chile. Para el estudio del reclutamiento y dispersión se desarrolló un modelo biofísico de dispersión larvaria que permite evaluar el efecto de la variabilidad oceanográfica y los rasgos biológicos (migración vertical de las larvas y desarrollo dependiente de la temperatura) en la distancia de dispersión, el éxito del reclutamiento, y los patrones de conectividad larval. Los resultados sugieren que, para ambas especies, la protección y el afloramiento costero no tienen un efecto sobre la inversión reproductiva y la condición de los individuos. Sin embargo, la protección sí tuvo un efecto sobre la talla y densidad de individuos generando claros patrones espaciales de producción de gametos. Se observó que la variación geográfica y temporal de los procesos de circulación dominaneltransportey la dispersióndelas larvas enlaregión, independientemente de los rasgos biológicos evaluados. La mayoría del reclutamiento fue alóctono, con niveles bajos de auto-reclutamiento y retención local, incluso para la especie con un tiempo de vida planctónica corto (F. latimarginata). Los patrones geográficos de salida y llegada fueron similares para ambas especies, observándose una mayor importancia relativa de la región norte del dominio de estudio. Estos resultados permiten identificar los principales determinantes de la producción de huevos, el éxito del reclutamiento y la distancia de dispersión para dos especies de gran interés comercial en Chile, información que podría guiar recomendaciones para el manejo y la conservación en una de las regiones costeras más productivas pero también más explotadas del mundo." -- TDX
 
moreShow More Titles
fewerShow Fewer Titles
Audience Level
0
Audience Level
1
  Kids General Special  
Audience level: 0.96 (from 0.96 for Biology an ... to 0.97 for Mediterran ...)

Alternative Names
Creu Palacín researcher

Creu Palacín wetenschapper

Palacín Cabañas, Creu

Palacín, Creu

Palacín, Cruz

Palacín i Cabañas, Cruz

Languages