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1.
Mar Drugs ; 21(5)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37233500

RESUMO

There is a growing interest in using brown algal extracts thanks to the bioactive substances they produce for adaptation to the marine benthic environment. We evaluated the anti-aging and photoprotective properties of two types of extracts (50%-ethanol and DMSO) obtained from different portions, i.e., apices and thalli, of the brown seaweed, Ericaria amentacea. The apices of this alga, which grow and develop reproductive structures during summer when solar radiation is at its peak, were postulated to be rich in antioxidant compounds. We determined the chemical composition and pharmacological effects of their extracts and compared them to the thallus-derived extracts. All the extracts contained polyphenols, flavonoids and antioxidants and showed significant biological activities. The hydroalcoholic apices extracts demonstrated the highest pharmacological potential, likely due to the higher content of meroditerpene molecular species. They blocked toxicity in UV-exposed HaCaT keratinocytes and L929 fibroblasts and abated the oxidative stress and the production of pro-inflammatory cytokines, typically released after sunburns. Furthermore, the extracts showed anti-tyrosinase and anti-hydrolytic skin enzyme activity, counteracting the collagenase and hyaluronidase degrading activities and possibly slowing down the formation of uneven pigmentation and wrinkles in aging skin. In conclusion, the E. amentacea apices derivatives constitute ideal components for counteracting sunburn symptoms and for cosmetic anti-aging lotions.


Assuntos
Phaeophyceae , Alga Marinha , Alga Marinha/química , Polifenóis , Phaeophyceae/química , Flavonoides/química , Antioxidantes/farmacologia , Antioxidantes/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química
2.
J Environ Manage ; 305: 114370, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34968935

RESUMO

Local, regional and global targets have been set to halt marine biodiversity loss. Europe has set its own policy targets to achieve Good Environmental Status (GES) of marine ecosystems by implementing the Marine Strategy Framework Directive (MSFD) across member states. We combined an extensive dataset across five Mediterranean ecoregions including 26 Marine Protected Areas (MPAs), their reference unprotected areas, and a no-trawl case study. Our aim was to assess if MPAs reach GES, if their effects are local or can be detected at ecoregion level or up to a Mediterranean scale, and which are the ecosystem components driving GES achievement. This was undertaken by using the analytical tool NEAT (Nested Environmental status Assessment Tool), which allows an integrated assessment of the status of marine systems. We adopted an ecosystem approach by integrating data from several ecosystem components: the seagrass Posidonia oceanica, macroalgae, sea urchins and fish. Thresholds to define the GES were set by dedicated workshops and literature review. In the Western Mediterranean, most MPAs are in good/high status, with P. oceanica and fish driving this result within MPAs. However, GES is achieved only at a local level, and the Mediterranean Sea, as a whole, results in a moderate environmental status. Macroalgal forests are overall in bad condition, confirming their status at risk. The results are significantly affected by the assumption that discrete observations over small spatial scales are representative of the total extension investigated. This calls for large-scale, dedicated assessments to realistically detect environmental status changes under different conditions. Understanding MPAs effectiveness in reaching GES is crucial to assess their role as sentinel observatories of marine systems. MPAs and trawling bans can locally contribute to the attainment of GES and to the fulfillment of the MSFD objectives. Building confidence in setting thresholds between GES and non-GES, investing in long-term monitoring, increasing the spatial extent of sampling areas, rethinking and broadening the scope of complementary tools of protection (e.g., Natura 2000 Sites), are indicated as solutions to ameliorate the status of the basin.


Assuntos
Biodiversidade , Ecossistema , Animais , Conservação dos Recursos Naturais , Europa (Continente) , Peixes , Mar Mediterrâneo
3.
Mar Drugs ; 19(1)2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374863

RESUMO

Inflammation and oxidative stress are part of the complex biological responses of body tissues to harmful stimuli. In recent years, due to the increased understanding that oxidative stress is implicated in several diseases, pharmaceutical industries have invested in the research and development of new antioxidant compounds, especially from marine environment sources. Marine seaweeds have shown the presence of many bioactive secondary metabolites, with great potentialities from both the nutraceutical and the biomedical point of view. In this study, 50%-ethanolic and DMSO extracts from the species C. amentacea var. stricta were obtained for the first time from seaweeds collected in the Ligurian Sea (north-western Mediterranean). The bioactive properties of these extracts were then investigated, in terms of quantification of specific antioxidant activities by relevant ROS scavenging spectrophotometric tests, and of anti-inflammatory properties in LPS-stimulated macrophages by evaluation of inhibition of inflammatory cytokines and mediators. The data obtained in this study demonstrate a strong anti-inflammatory effect of both C. amentacea extracts (DMSO and ethanolic). The extracts showed a very low grade of toxicity on RAW 264.7 macrophages and L929 fibroblasts and a plethora of antioxidant and anti-inflammatory effects that were for the first time thoroughly investigated. The two extracts were able to scavenge OH and NO radicals (OH EC50 between 392 and 454 µg/mL; NO EC50 between 546 and 1293 µg/mL), to partially rescue H2O2-induced RAW 264.7 macrophages cell death, to abate intracellular ROS production in H2O2-stimulated macrophages and fibroblasts and to strongly inhibit LPS-induced inflammatory mediators, such as NO production and IL-1α, IL-6, cyclooxygenase-2 and inducible NO synthase gene expression in RAW 264.7 macrophages. These results pave the way, for the future use of C. amentacea metabolites, as an example, as antioxidant food additives in antiaging formulations as well as in cosmetic lenitive lotions for inflamed and/or damaged skin.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Fibroblastos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Phaeophyceae/metabolismo , Animais , Anti-Inflamatórios/isolamento & purificação , Antioxidantes/isolamento & purificação , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citocinas/genética , Citocinas/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Peróxido de Hidrogênio/toxicidade , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo
4.
Anal Bioanal Chem ; 408(3): 915-32, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26608282

RESUMO

Blooms of benthic dinoflagellates of the genus Ostreopsis (mainly O. cf. ovata and occasionally O. cf. siamensis) represent a serious concern for humans in the Mediterranean area, due to production of palytoxin-like compounds listed among the most potent marine toxins known. In this work, six strains of Ostreopsis sp. from Cyprus Island were analyzed through an integrated approach based on molecular, chemical, and eco-toxicological methods. Cypriot Ostreopsis sp. was found to be a species distinct from O. cf. ovata and O. cf. siamensis, belonging to the Atlantic/Mediterranean Ostreopsis spp. clade. Some variability in toxin profiles emerged: three strains produced ovatoxin-a (OVTX-a), OVTX-d, OVTX-e, and isobaric palytoxin, so far found only in O. cf. ovata; the other three strains produced only new palytoxin-like compounds, which we named ovatoxin-i, ovatoxin-j1, ovatoxin-j2, and ovatoxin-k. The new ovatoxins present the same carbon skeleton as ovatoxin-a, differing primarily in an additional C2H2O2 moiety and an unsaturation in the region C49-C52. Other minor structural differences were found, including the presence of a hydroxyl group at C44 (in OVTX-j1 and OVTX-k) and the lack of a hydroxyl group in the region C53-C78 (in OVTX-i and OVTX-j1). The toxin content of the analyzed Ostreopsis sp. strains was in the range 0.06-2.8 pg cell(-1), definitely lower than that of a Ligurian O. cf. ovata strain cultured under the same conditions. Accordingly, an eco-toxicological test on Artemia salina nauplii demonstrated that Ostreopsis sp. presents a very low toxicity compared to O. cf. ovata. The whole of these data suggest that Ostreopsis sp. from Cyprus Island poses a relatively low risk to humans.


Assuntos
Dinoflagellida/química , Toxinas Marinhas/química , Toxinas Marinhas/toxicidade , Animais , Artemia/efeitos dos fármacos , Cromatografia Líquida , Dinoflagellida/classificação , Dinoflagellida/metabolismo , Ilhas , Toxinas Marinhas/metabolismo , Espectrometria de Massas , Estrutura Molecular
5.
J Phycol ; 52(6): 1064-1084, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27633521

RESUMO

The new benthic toxic dinoflagellate, Ostreopsis fattorussoi sp. nov., is described from the Eastern Mediterranean Sea, Lebanon and Cyprus coasts, and is supported by morphological and molecular data. The plate formula, Po, 3', 7″, 6c, 7s, 5‴, 2'''', is typical for the Ostreopsis genus. It differs from all other Ostreopsis species in that (i) the curved suture between plates 1' and 3' makes them approximately hexagonal, (ii) the 1' plate lies in the left half of the epitheca and is obliquely orientated leading to a characteristic shape of plate 6″. The round thecal pores are bigger than the other two Mediterranean species (O. cf. ovata and O. cf. siamensis). O. fattorussoi is among the smallest species of the genus (DV: 60.07 ± 5.63 µm, AP: 25.66 ± 2.97 µm, W: 39.81 ± 5.05 µm) along with O. ovata. Phylogenetic analyses based on the LSU and internal transcribed spacer rDNA shows that O. fattorussoi belongs to the Atlantic/Mediterranean Ostreopsis spp. clade separated from the other Ostreopsis species. Ostreopsis fattorussoi produces OVTX-a and structural isomers OVTX-d and -e, O. cf. ovata is the only other species of this genus known to produce these toxins. The Lebanese O. fattorussoi did not produce the new palytoxin-like compounds (ovatoxin-i, ovatoxin-j1 , ovatoxin-j2 , and ovatoxin-k) that were previously found in O. fattorussoi from Cyprus. The toxin content was in the range of 0.28-0.94 pg · cell-1 . On the Lebanon coast, O. fattorussoi was recorded throughout the year 2015 (temperature range 18°C-31.5°C), with peaks in June and August.


Assuntos
Dinoflagellida/classificação , Chipre , DNA de Algas/genética , Dinoflagellida/genética , Dinoflagellida/ultraestrutura , Líbano , Mar Mediterrâneo , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie
6.
Ecology ; 95(6): 1451-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25039209

RESUMO

Thresholds profoundly affect our understanding and management of ecosystem dynamics, but we have yet to develop practical techniques to assess the risk that thresholds will be crossed. Combining ecological knowledge of critical system interdependencies with a large-scale experiment, we tested for breaks in the ecosystem interaction network to identify threshold potential in real-world ecosystem dynamics. Our experiment with the bivalves Macomona liliana and Austrovenus stutchburyi on marine sandflats in New Zealand demonstrated that reductions in incident sunlight changed the interaction network between sediment biogeochemical fluxes, productivity, and macrofauna. By demonstrating loss of positive feedbacks and changes in the architecture of the network, we provide mechanistic evidence that stressors lead to break points in dynamics, which theory predicts predispose a system to a critical transition.


Assuntos
Bivalves/fisiologia , Ecossistema , Animais , Modelos Biológicos , Nova Zelândia , Oceanos e Mares
7.
Mar Environ Res ; 198: 106537, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38728798

RESUMO

Marine macroalgal forests are facing unprecedented challenges worldwide due to the accelerating impacts of climate change. These ecosystems play a crucial role in supporting biodiversity, coastal ecosystem functions and services, and are indeed object of several conservation and restoration measures. The Mediterranean Sea is warming faster than the oceans and thermal anomalies are occurring with increasing intensity, frequency and duration. Along the Mediterranean coasts, Cystoseira sensu lato species are the main representatives of macroalgal forests and their decline has been widely documented. Some relevant achievements in the implementation of ecological restoration have been obtained, but rising temperatures and the occurrence of thermal anomalies increasingly threaten the success of these restoration attempts. In the summer of 2022, ex-situ restoration actions of Ericaria amentacea were carried out by collecting fertile material from three donor sites of the Italian coasts along a latitudinal gradient, during the period of sexual maturity (June/July). Noteworthy during the summer of 2022, anomalous thermal conditions were recorded at the donor sites, with sea surface temperatures exceeding the climatological mean up to 4.3 °C and heatwaves lasting up to 78 days. Our results suggest that these thermal anomalies may have affected the culture of the embryos in both the pre- and post-zygotic phases, resulting in significantly low culture efficiency at the three donor sites. The reproductive structures showed some abnormalities, fertilization of eggs was lower and embryo growth was slower, resulting in lower percent cover of seedlings on the tiles and lower survival rate. The observations underscore the vulnerability of Mediterranean algal forests to global change and highlight additional challenges for their restoration due to the increasing frequency and severity of thermal anomalies, emphasizing the need for adaptive strategies and a comprehensive understanding of the species in a changing climate. Marine forest restoration requires long lasting projects, to allow for long-term monitoring and better understanding the biology of the species and for mitigating stochastic events that can cause the temporary failure of efforts.


Assuntos
Mudança Climática , Mar Mediterrâneo , Temperatura , Ecossistema , Florestas , Conservação dos Recursos Naturais , Alga Marinha/fisiologia , Ericaceae/fisiologia , Recuperação e Remediação Ambiental , Itália
8.
Harmful Algae ; 136: 102651, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38876529

RESUMO

Ostreopsis spp. blooms have been occurring in the last two decades in the Mediterranean Sea in association with a variety of biotic and abiotic substrata (macroalgae, seagrasses, benthic invertebrates, sand, pebbles and rocks). Cells proliferate attached to the surfaces through mucilaginous trichocysts, which lump together microalgal cells, and can also be found in the plankton and on floating aggregates: such tychoplanktonic behavior makes the quantitative assessment of blooms more difficult than planktonic or benthic ones. Different techniques have been so far applied for quantifying cell abundances of benthic microalgae for research, monitoring and risk assessment purposes. In this context, the Benthic Dinoflagellates Integrator (BEDI), a non-destructive quantification method for benthic dinoflagellate abundances, was developed and tested within the EU ENPI-CBCMED project M3-HABs. This device allows mechanical detachment of cells without collecting the benthic substrate, providing an integrated assessment of both epiphytic and planktonic cells, i.e. of the number of cells potentially made available in the water volume from "resuspension" which could have harmful effects on other organisms (including humans). The present study confirms the effectiveness of the BEDI sampling device across different environments across the Mediterranean Sea and constitutes the first large-scale study of Ostreopsis spp. blooms magnitude in function of different macro- and meso­habitat features across the basin.


Assuntos
Dinoflagellida , Proliferação Nociva de Algas , Dinoflagellida/fisiologia , Mar Mediterrâneo , Monitoramento Ambiental/métodos , Microalgas/fisiologia , Água do Mar
9.
Harmful Algae ; 113: 102199, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35287932

RESUMO

In recent decades, recurrent Ostreopsis spp. blooms have been recorded throughout the globe, causing public health issues and mass mortalities of invertebrates. Ostreopsis species are benthic and develop in shallow waters in close relation with a substrate, but possible substrate preferences are still ambiguous. Bloom develops on both living and dead substrates and several interacting biotic and abiotic factors acting at different spatial scales can potentially foster or regulate Ostreopsis spp. development. The objective of this review is to collect and summarize information on Ostreopsis spp. blooms related to the habitat at different spatial scales, in order to assess preferences and trends. References including Ostreopsis spp. samplings in the field were analysed in this review, as potentially including information about the micro- (substrate), meso­ (community) and macrohabitat (ecosystem) related to Ostreopsis spp. blooms. The sampled substrate and the ecosystem where Ostreopsis spp. were collected were generally reported and described in the studies, while the description of the mesohabitat was rarely reported. Ostreopsis spp. were generally described as attached to biotic substrates and in particular, macroalgae, even in studies conducted in coral reefs, where macroalgae are generally not dominant (but they can be in case of coral reef degradation). In both temperate and tropical areas, Ostreopsis spp. were mostly sampled on algal species usually forming medium or low complexity communities (erect or turf-forming algae), often characteristic from post-regime shift scenarios, and rarely on canopy-forming species (such as fucoids and kelps). This literature review highlights the need of collecting more information about the mesohabitat where important Ostreopsis spp. blooms develop, as much as of the underlying mechanisms driving eventual differences on Ostreopsis spp. abundances. This knowledge would allow a better risk assessment of Ostreopsis spp. blooms, identifying areas at high risk on the base of the benthic habitats.


Assuntos
Dinoflagellida , Alga Marinha , Recifes de Corais , Dinoflagellida/fisiologia , Ecossistema
10.
Open Biol ; 11(12): 210177, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34905702

RESUMO

There is a surprisingly high morphological similarity between multilamellar concentric thylakoids in cyanobacteria and the myelin sheath that wraps the nerve axons. Thylakoids are multilamellar structures, which express photosystems I and II, cytochromes and ATP synthase necessary for the light-dependent reaction of photosynthesis. Myelin is a multilamellar structure that surrounds many axons in the nervous system and has long been believed to act simply as an insulator. However, it has been shown that myelin has a trophic role, conveying nutrients to the axons and producing ATP through oxidative phosphorylation. Therefore, it is tempting to presume that both membranous structures, although distant in the evolution tree, share not only a morphological but also a functional similarity, acting in feeding ATP synthesized by the ATP synthase to the centre of the multilamellar structure. Therefore, both molecular structures may represent a convergent evolution of life on Earth to fulfill fundamentally similar functions.


Assuntos
Trifosfato de Adenosina/metabolismo , Cianobactérias/ultraestrutura , Bainha de Mielina/ultraestrutura , Tilacoides/ultraestrutura , Complexos de ATP Sintetase/metabolismo , Animais , Evolução Biológica , Cianobactérias/metabolismo , Metabolismo Energético , Humanos , Bainha de Mielina/metabolismo , Fosforilação Oxidativa , Tilacoides/metabolismo
11.
Ecotoxicology ; 19(3): 520-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19898934

RESUMO

The effect of exposures to the insecticide chlorpyrifos on the larval stages of Paracentrotus lividus (Echinodermata, Euechinoidea) up to metamorphosis was investigated with the aim to identify novel risk biomarkers and a new promising model for toxicity tests. The planktonic sea urchin larvae have the ability to undergo a variable exploratory period, up to the choice of a suitable substrate for adult benthonic life. The juvenile bud (called rudiment) is built inside the larval body that, on environmental cues represented by a variety of signal molecules, is reabsorbed by apoptosis and releases the juvenile on the substrate. In this dialogue between larvae and environment, contaminants interfere with the signals reception, and may alter in dose-dependent way the correct regulation of environment-larva-rudiment interaction. Such interaction is shown by larval plasticity, i.e. the ability of the larva to change body proportions according to the environmental conditions. When exposed to low doses of chlorpyriphos (10(-7) to 10(-10) M) since 2-days after fertilization, the larvae showed altered size and shape, but all reached the metamorphosis at the same time as controls, and in the same percentage. Exposures to high concentrations such as 10(-4) to 10(-6) M since 2-days after fertilization did not allow larval growth and differentiation. Exposures at later stages caused reabsorption of larval structures within a few hours and precocious release of the immature rudiments, followed by death of the juveniles. Although the mechanism of chlorpyriphos toxicity in sea urchin larvae is still rather unclear, the measurable stress biomarkers can constitute the basis for new toxicity tests.


Assuntos
Clorpirifos/toxicidade , Metamorfose Biológica/efeitos dos fármacos , Paracentrotus/efeitos dos fármacos , Praguicidas/toxicidade , Acetilcolinesterase/metabolismo , Animais , Biomarcadores/metabolismo , Relação Dose-Resposta a Droga , Larva/efeitos dos fármacos , Paracentrotus/crescimento & desenvolvimento , Testes de Toxicidade , Poluentes Químicos da Água/toxicidade
12.
Proc Biol Sci ; 276(1671): 3209-17, 2009 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-19553254

RESUMO

Despite the increasing evidence of drastic and profound changes in many ecosystems, often referred to as regime shifts, we have little ability to understand the processes that provide insurance against such change (resilience). Modelling studies have suggested that increased variance may foreshadow a regime shift, but this requires long-term data and knowledge of the functional links between key processes. Field-based research and ground-truthing is an essential part of the heuristic that marries theoretical and empirical research, but experimental studies of resilience are lagging behind theory, management and policy requirements. Empirically, ecological resilience must be understood in terms of community dynamics and the potential for small shifts in environmental forcing to break the feedbacks that support resilience. Here, we integrate recent theory and empirical data to identify ways we might define and understand potential thresholds in the resilience of nature, and thus the potential for regime shifts, by focusing on the roles of strong and weak interactions, linkages in meta-communities, and positive feedbacks between these and environmental drivers. The challenge to theoretical and field ecologists is to make the shift from hindsight to a more predictive science that is able to assist in the implementation of ecosystem-based management.


Assuntos
Ecossistema , Previsões/métodos , Modelos Teóricos , Animais , Dinâmica Populacional , Pesquisa , Fatores de Tempo
13.
Heliyon ; 5(10): e02628, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31720451

RESUMO

[This corrects the article DOI: 10.1016/j.heliyon.2019.e02449.].

14.
Heliyon ; 5(9): e02449, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31687554

RESUMO

The green alga Caulerpa cylindracea Sonder is one of the most infamous and threatening invasive species in the Mediterranean Sea. Since 1985, it started rapidly spreading to all Mediterranean regions causing many ecological changes on natural communities. In the present study, we present an example of this proliferation with the first record in the Marine Protected Area of Tremiti Island (MPATI) in the South Adriatic Sea. Fifteen sites along the coast and 5 different depths have been investigated. Our results provide eveidence of a wide invasion of this pest in three islands, San Domino, San Nicola and Capraia. This study fills a particular data gap in the ongoing biomonitoring of invasive seaweeds in the Mediterranean Sea representing a base line of this invasive species for the MPATI.

15.
Aquat Toxicol ; 210: 19-29, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30818112

RESUMO

CO2 atmospheric pressure is increasing since industrial revolution, leading to a lowering of the ocean surface water pH, a phenomenon known as ocean acidification, with several reported effects on individual species and cascading effects on marine ecosystems. Despite the great amount of literature on ocean acidification effects on calcifying organisms, the response of their reproductive system still remains poorly known. In the present study, we investigated the histopathological effects of low pH on the gonads of three key macroinvertebrates of the Terra Nova Bay (Ross Sea) littoral area: the sea urchin Sterechinus neumayeri, the sea star Odontaster validus and the scallop Adamussium colbecki. After 1 month of exposure at control (8.12) and reduced (7.8 and 7.6) pH levels, we dissected the gonads and performed histological analyses to detect potential differences among treatments. Results showed significant effects on reproductive conditions of A. colbecki and S. neumayeri, while O. validus did not show any kind of alteration. Present results reinforce the need to focus on ocean acidification effects on soft tissues, particularly the gonads, whose damage may exert large effects on the individual fitness, with cascading effects on the population dynamic of the species.


Assuntos
Gônadas/efeitos dos fármacos , Pectinidae/efeitos dos fármacos , Ouriços-do-Mar/efeitos dos fármacos , Água do Mar/química , Estrelas-do-Mar/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Regiões Antárticas , Ecossistema , Concentração de Íons de Hidrogênio , Oceanos e Mares , Pectinidae/crescimento & desenvolvimento , Reprodução/efeitos dos fármacos , Ouriços-do-Mar/crescimento & desenvolvimento , Estrelas-do-Mar/crescimento & desenvolvimento
16.
Mar Environ Res ; 149: 90-99, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31254931

RESUMO

Atmospheric pCO2 has increased since the industrial revolution leading to a lowering of the ocean surface water pH, a phenomenon called ocean acidification (OA). OA is claimed to be a major threat for marine organisms and ecosystems and, particularly, for Polar regions. We explored the impact of OA on the shell mechanical properties of the Antarctic scallop Adamussium colbecki exposed for one month to acidified (pH 7.6) and natural conditions (unmanipulated littoral water), by performing Scanning Electron Microscopy, nanoindentation and Vickers indentation on the scallop shell. No effect of pH could be detected either in crystal deposition or in the mechanical properties. A. colbecki shell was found to be resistant to OA, which suggests this species to be able to face a climate change scenario that may threat the persistence of the endemic Antarctic species. Further investigation should be carried out in order to elucidate the destiny of this key species in light of global change.


Assuntos
Exoesqueleto , Concentração de Íons de Hidrogênio , Pectinidae , Água do Mar/química , Exoesqueleto/ultraestrutura , Animais , Regiões Antárticas , Organismos Aquáticos , Mudança Climática , Microscopia Eletrônica de Varredura , Pectinidae/ultraestrutura
17.
PeerJ ; 7: e7290, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31367482

RESUMO

In the Mediterranean Sea, brown algae belonging to the Cystoseira genus play a valuable role as foundation species. Due to evidences of regression/loss of the habitats of these species caused by the interplay of human and climatic disturbances, active restoration measures have been encouraged by EU regulations. In particular, nondestructive restoration techniques, which avoid the depletion of threatened species in donor populations, are strongly recommended. In the framework of the EU project ROCPOP-Life, the first ex situ outplanting experience of Cystoseira amentacea var. stricta has been implemented in the Cinque Terre Marine Protected Area (northwestern Mediterranean). A total of 400 clay tiles, hosting approximately three mm-long germlings of C. amentacea, were fixed to the rocky shore with screws: the tiles were monitored for the next 2 months by photographic sampling, and survival (presence/absence of juveniles on the tiles), cover and growth were assessed. Additional sampling was performed 6 months after tile deployment, after which an unprecedented storm surge severely affected the restoration performance. After 2 months, over 40% of the tiles were covered with Cystoseira juveniles, which reached approximately eight mm in total length. The tiles that survived the storm hosted three to six cm-long juveniles. The high cover (≥25%), assuring moisture and shading, and the appropriate size of the juveniles, to avert micro-grazing, at time of deployment were key to the survival and growth of the outplanted juveniles, increasing the potential for restoration success. Our findings show that outplanting of midlittoral canopy-forming species is a feasible approach for restoration efforts, with particular attention given to the early phases: (i) laboratory culture, (ii) transport, and (iii) juvenile densities. These results are strongly encouraging for the implementation of restoration actions for C. amentacea on a large scale, in light of EU guidelines.

18.
Mar Pollut Bull ; 56(9): 1637-45, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18603267

RESUMO

The key species Posidonia oceanica is the dominant endemic seagrass in the Mediterranean Sea and its meadows are considered as one of the most important and productive ecosystems in coastal waters. Covering the seabed from the surface down to about 40 m, meadows of P. oceanica are often affected by mechanical direct damages caused by boat anchoring and mooring activities. Negative effects of these activities have been shown to be recorded by P. oceanica at two different levels: the individual level (phenology of the plant) and the population level (structure of the meadow). We investigated the effect of an anchoring chain system on the P. oceanica meadow of Prelo cove (NW Mediterranean Sea) at two different depths (shallow, deep) and at three different situations of P. oceanica bottom cover (high, medium, low). Several standardized descriptors of the meadow health, working either at the individual or at the population level, were analysed in order to quantify the impact of the deployment of the chain system. A symmetrical BACI design was adopted to detect the impact, where multiple disturbed sites were contrasted with multiple controls in two distinct times, i.e. right few days after the chain settling (early) and 4 months later the disturbance (late). The anchoring chain system has been shown to strongly affect the meadow in terms of shoot density decline and rhizome baring, especially in the deep portions and where the cover of the meadow was low. All descriptors working at the population level proved effective in detecting the impact of the anchoring system. In contrast, descriptors working at the individual level did not show a consistent response to the impact. Our results pointed out the imperative necessity to proper regulate the boat anchoring and mooring activities on the P. oceanica meadows and the adoption of seagrass friendly mooring technology is thus recommended.


Assuntos
Alismatales/crescimento & desenvolvimento , Navios/instrumentação , Alismatales/anatomia & histologia , Análise de Variância , Mar Mediterrâneo , Dinâmica Populacional
19.
R Soc Open Sci ; 5(8): 171700, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30224980

RESUMO

Metacommunity theory highlights the potential of ß-diversity as a useful link to empirical research, especially in diverse systems where species exhibit a range of stage-dependent dispersal characteristics. To investigate the importance of different components and scales of ß-diversity in community assembly, we conducted a large-scale disturbance experiment and compared relative recovery across multiple sites and among plots within sites on the rocky shore. Six sites were spread along 80 km of coastline and, at each site, five plots were established, matching disturbed and undisturbed quadrats. Recovery was not complete at any of the sites after 1 year for either epibenthos (mostly composed of macroalgae and, locally, mussels) or infauna. Significant differences in recovery among sites were observed for epibenthos but not for infauna, suggesting that different community assembly processes were operating. This was supported by epibenthos in the recovering plots having higher species turnover than in undisturbed sediment, and recovery well predicted by local diversity, while infaunal recovery was strongly influenced by the epibenthic community's habitat complexity. However, infaunal community recovery did not simply track formation of habitat by recovering epibenthos, but appeared to be overlain by within-site and among-site aspects of infaunal ß-diversity. These results suggest that documenting changes in the large plants and animals alone will be a poor surrogate for rocky shore community assembly processes. No role for ecological connectivity (negative effect of among-site ß-diversity) in driving recovery was observed, suggesting a low risk of effects from multiple disturbances propagating along the coast, but a limited resilience at the site scale to large-scale disturbances such as landslides or oil spills.

20.
PLoS One ; 13(12): e0206826, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30596657

RESUMO

According to the Water Framework Directive, within 2015 European Union countries must reach and maintain the "good" Ecological Status (ES), quantified through indices based on key biological elements as indicators. Along the Ligurian shallow rocky coasts (NW Italy), a macroalgae based index (CARtography of LITtoral and upper-sublittoral benthic communities, CARLIT), calibrated according to national characteristics and management needs, has been applied by the Regional Environmental Agency over the last ten years. In 2015, at least a "good" ES was achieved in all Ligurian water bodies except one, located in the Eastern Ligurian coastline, characterized by the lack of the most sensitive species, Cystoseira amentacea var. stricta. A general ES improvement has been observed along the Ligurian coastline, also in comparison with other quality indices (macroinvertebrates and fecal bacteria), and in particular in the Genoa water body, as proved by a relevant increase of C. amentacea abundance, probably as a consequence of enhancement in wastewater treatments. In the present study, the reliability of the observed improvement of the ES over a decade has been assessed, teasing apart intra-seasonal and operator-related variability. These results support the reliability of monitoring procedures carried out though the CARLIT Index and highlight the need and the effectiveness of reduction measures for anthropogenic impacts in order to achieve the ES required by European directives.


Assuntos
Ecossistema , Microalgas/crescimento & desenvolvimento , Phaeophyceae/crescimento & desenvolvimento , Itália , Microalgas/classificação , Phaeophyceae/classificação
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