The Experts below are selected from a list of 59439 Experts worldwide ranked by ideXlab platform
Antoine M. Dujon - One of the best experts on this subject based on the ideXlab platform.
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A groundwater-fed coastal inlet as habitat for the Caribbean queen conch Lobatus gigas-an acoustic telemetry and space use analysis
Marine Ecology Progress Series, 2017Co-Authors: Thomas C. Stieglitz, Antoine M. DujonAbstract:The queen conch Lobatus (Strombus) gigas, a Marine snail, is among the most important fisheries resources of the Caribbean region. To provide effective protection in Marine reserves, a good understanding of its habitat usage is essential. Queen conches commonly inhabit Marine Habitats. In this study, its activity space in a marginal estuarine-like habitat, the groundwater-fed inlet of Xel-Ha (Mexico) was determined using high-resolution acoustic telemetry (VEMCO Positioning System). Thirty-eight animals with syphonal lengths ranging from 80 to 200 mm were tagged, 1 of them with an accelerometer tag. Their trajectories were recorded for 20 mo at 5 m resolution in a closely spaced array of 12 receivers. Space-time kernel home ranges ranged from 1000 to 18 500 m(2) with an ontogenetically increasing trend. Juveniles, subadults and most adults displayed continuous, non-patchy home ranges consistent with the typical intensive feeding activity by this fast-growing gastropod. In some adults, Levy flight-like fragmentation of home ranges was observed that may be related to feeding range expansion or other ecological drivers such as the breeding cycle. The observed small home ranges indicate that the space use of queen conch in this estuarine-like habitat is not conditioned by food availability, and despite environmental stress due to daily low-oxygen conditions, space use is comparable to that observed in more typical Marine Habitats. In a Marine reserve context, the groundwater-fed inlet provides adequate protection of this inshore queen conch population. Such marginal Habitats may play an increasingly important role in conservation management as pressure on populations increase.
Geoffrey Allan Boxshall - One of the best experts on this subject based on the ideXlab platform.
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global diversity of cumaceans tanaidaceans crustacea cumacea tanaidacea in freshwater
Hydrobiologia, 2008Co-Authors: Damia Jaume, Geoffrey Allan BoxshallAbstract:Cumacea and Tanaidacea are marginal groups in continental waters. Although many euryhaline species from both groups are found in estuaries and coastal lagoons, most occur only temporarily in non-Marine Habitats, appearing unable to form stable populations there. A total of 21 genuinely non-Marine cumaceans are known, mostly concentrated in the Ponto-Caspian region, and only four tanaids have been reported from non-Marine environments. Most non-Marine cumaceans (19 species) belong in the Pseudocumatidae and appear restricted to the Caspian Sea (with salinity up to 13%) and its peripheral fluvial basins, including the northern, lower salinity zones of the Black Sea (Sea of Azov). There are nine Ponto-Caspian genera, all endemic to the region. Only two other taxa (in the family Nannastacidae) occur in areas free of any Marine-water influence, in river basins in North and South America. Both seem able to survive in waters of raised salinity of the lower reaches of these fluvial systems; but neither has been recorded in full salinity Marine environments. The only non-Marine tanaidacean thus far known lives in a slightly brackish inland spring in Northern Australia. The genus includes a second species, from a brackish-water lake at the Bismarck Archipelago, tentatively included here as non-Marine also. Two additional species of tanaidaceans have been reported from non-Marine Habitats but both also occur in the sea.
Laura Airoldi - One of the best experts on this subject based on the ideXlab platform.
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the overlooked role of biotic factors in controlling the ecological performance of artificial Marine Habitats
Journal of Applied Ecology, 2016Co-Authors: Shimrit Perkolfinkel, Filippo Ferrario, Ljiljana Ivesa, Andrej Jaklin, Laura AiroldiAbstract:1. Artificial structures are sprawling in Marine seascapes as a result of burgeoning coastal populations, increasing development and energy demand, and greater risks from climate change, storm surges and sea level rise. Interest in designing Marine developments that maintain vital ecosystems and critical services is growing, but progress requires understanding the factors that influence the ecological performance of these novel artificial Habitats. 2. We combined field observations and experiments along 500 km of the North Adriatic coastline to analyse the performance of artificial substrata as Habitats to support canopyforming algae belonging to the genus Cystoseira, among the most ecologically relevant foundation species along rocky Mediterranean coastlines. We aimed to: clarify the underlying factors controlling the growth of Cystoseira in the artificial habitat ; contrast the relative importance of these factors between artificial and natural Habitats ; and test the generality of the results across different sites and species of Cystoseira. 3. We found that: (i) the growth of canopy algae was significantly lower on artificial structures compared to rocky reefs ; (ii) such lower growth of canopy algae was not related to less favourable abiotic conditions but to higher biotic disturbance from both consumptive and nonconsumptive interactions on the artificial structures compared to the natural reef ; and iii) this was consistent across different study sites and canopy-forming species. 4. We conclude that biological factors influencing the growth of canopy algae, such as herbivory or other nonconsumptive disturbances, can differ substantially between artificial and natural Habitats. The unusually large and previously unreported biotic pressure characterizing many artificial structures can negatively affect their performance as Habitats to support ecologically relevant, foundation species. 5. Synthesis and applications. While nearly all considerations to improve the ecological performance of hard Marine infrastructures focus on abiotic factors (e.g. construction materials, surface texture, habitat complexity or water quality), careful consideration of critical biotic factors is also needed to further progress the green engineering of sprawling Marine infrastructures.
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loss and recovery potential of Marine Habitats an experimental study of factors maintaining resilience in subtidal algal forests at the adriatic sea
PLOS ONE, 2010Co-Authors: Shimrit Perkolfinkel, Laura AiroldiAbstract:Background Predicting and abating the loss of natural Habitats present a huge challenge in science, conservation and management. Algal forests are globally threatened by loss and severe recruitment failure, but our understanding of resilience in these systems and its potential disruption by anthropogenic factors lags well behind other Habitats. We tested hypotheses regarding triggers for decline and recovery potential in subtidal forests of canopy-forming algae of the genus Cystoseira. Methodology/Principal Findings By using a combination of historical data, and quantitative in situ observations of natural recruitment patterns we suggest that recent declines of forests along the coasts of the north Adriatic Sea were triggered by increasing cumulative impacts of natural- and human-induced habitat instability along with several extreme storm events. Clearing and transplantation experiments subsequently demonstrated that at such advanced stages of ecosystem degradation, increased substratum stability would be essential but not sufficient to reverse the loss, and that for recovery to occur removal of the new dominant space occupiers (i.e., opportunistic species including turf algae and mussels) would be required. Lack of surrounding adult canopies did not seem to impair the potential for assisted recovery, suggesting that in these systems recovery could be actively enhanced even following severe depletions. Conclusions/Significance We demonstrate that sudden habitat loss can be facilitated by long term changes in the biotic and abiotic conditions in the system, that erode the ability of natural ecosystems to absorb and recover from multiple stressors of natural and human origin. Moreover, we demonstrate that the mere restoration of environmental conditions preceding a loss, if possible, may be insufficient for ecosystem restoration, and is scarcely cost-effective. We conclude that the loss of complex Marine Habitats in human-dominated landscapes could be mitigated with appropriate consideration and management of incremental habitat changes and of attributes facilitating system recovery.
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loss status and trends for coastal Marine Habitats of europe
Oceanography and Marine Biology, 2007Co-Authors: Laura Airoldi, Michael W BeckAbstract:Over the centuries, land reclamation, coastal development, overfishing and pollution have nearly eliminated European wetlands, seagrass meadows, shellfish beds, biogenic reefs and other productive and diverse coastal Habitats. It is estimated that every day between 1960 and 1995, a kilometre of European coastline was developed. Most countries have estimated losses of coastal wetlands and seagrasses exceeding 50% of the original area with peaks above 80% for many regions. Conspicuous declines, sometimes to virtual local disappearance of kelps and other complex macroalgae, have been observed in several countries. A few dominant threats have led to these losses over time. The greatest impacts to wetlands have consistently been land claim and coastal development. The greatest impacts to seagrasses and macroalgae are presently associated with degraded water quality while in the past there have been more effects from destructive fishing and diseases. Coastal development remains an important threat to seagrasses. For biogenic Habitats, such as oyster reefs and maerls, some of the greatest impacts have been from destructive fishing and overexploitation with additional impacts of disease, particularly to native oysters. Coastal development and defence have had the greatest known impacts on soft-sediment Habitats with a high likelihood that trawling has affected vast areas. The concept of 'shifting baselines', which has been applied mostly to the inadequate historical perspective of fishery losses, is extremely relevant for habitat loss more generally. Most habitat loss estimates refer to a relatively short time span primarily within the last century. However, in some regions, most estuarine and near-shore coastal Habitats were already severely degraded or driven to virtual extinction well before 1900. Native oyster reefs were ecologically extinct by the 1950s along most European coastlines and in many bays well before that. These shellfish reefs are among the most endangered coastal Habitats, but they receive some of the least protection. Nowadays less than 15% of the European coastline is considered in 'good' condition. Those fragments of native Habitats that remain are under continued threat, and their management is not generally informed by adequate knowledge of their distribution and status. There are many policies and directives aimed at reducing and reversing these losses but their overall positive benefits have been low. Further neglecting this long history of habitat loss and transformation may ultimately compromise the successful management and future sustainability of those few fragments of native and semi-native coastal Habitats that remain in Europe.
Irene Wagner-döbler - One of the best experts on this subject based on the ideXlab platform.
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Phylogenomics of Rhodobacteraceae reveals evolutionary adaptation to Marine and non-Marine Habitats
The ISME Journal, 2017Co-Authors: Meinhard Simon, Carmen Scheuner, Jan P. Meier-kolthoff, Marcus Ulbrich, Hans-peter Klenk, Irene Wagner-döbler, Dietmar Schomburg, Thorsten Brinkhoff, Jörn Petersen, Markus GökerAbstract:Marine Rhodobacteraceae ( Alphaproteobacteria ) are key players of biogeochemical cycling, comprise up to 30% of bacterial communities in pelagic environments and are often mutualists of eukaryotes. As ‘ Roseobacter clade’, these ‘roseobacters’ are assumed to be monophyletic, but non-Marine Rhodobacteraceae have not yet been included in phylogenomic analyses. Therefore, we analysed 106 genome sequences, particularly emphasizing gene sampling and its effect on phylogenetic stability, and investigated relationships between Marine versus non-Marine habitat, evolutionary origin and genomic adaptations. Our analyses, providing no unequivocal evidence for the monophyly of roseobacters, indicate several shifts between Marine and non-Marine Habitats that occurred independently and were accompanied by characteristic changes in genomic content of orthologs, enzymes and metabolic pathways. Non-Marine Rhodobacteraceae gained high-affinity transporters to cope with much lower sulphate concentrations and lost genes related to the reduced sodium chloride and organohalogen concentrations in their Habitats. Marine Rhodobacteraceae gained genes required for fucoidan desulphonation and synthesis of the plant hormone indole 3-acetic acid and the compatible solutes ectoin and carnitin. However, neither plasmid composition, even though typical for the family, nor the degree of oligotrophy shows a systematic difference between Marine and non-Marine Rhodobacteraceae . We suggest the operational term ‘ Roseobacter group’ for the Marine Rhodobacteraceae strains.
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Aerobic Anoxygenic Photosynthesis in Roseobacter Clade Bacteria from Diverse Marine Habitats
Applied and Environmental Microbiology, 2003Co-Authors: Martin Allgaier, Heike Uphoff, Andreas Felske, Irene Wagner-döblerAbstract:The Marine Roseobacter clade comprises several genera of Marine bacteria related to the uncultured SAR83 cluster, the second most abundant Marine picoplankton lineage. Cultivated representatives of this clade are physiologically heterogeneous, and only some have the capability for aerobic anoxygenic photosynthesis, a process of potentially great ecological importance in the world's oceans. In an attempt to correlate phylogeny with ecology, we investigated the diversity of Roseobacter clade strains from various Marine Habitats (water samples, biofilms, laminariae, diatoms, and dinoflagellate cultures) by using the 16S rRNA gene as a phylogenetic marker gene. The potential for aerobic anoxygenic photosynthesis was determined on the genetic level by PCR amplification and sequencing of the pufLM genes of the bacterial photosynthesis reaction center and on the physiological level by detection of bacteriochlorophyll (Bchl) a. A collection of ca. 1,000 Marine isolates was screened for members of the Marine Roseobacter clade by 16S rRNA gene-directed multiplex PCR and sequencing. The 42 Roseobacter clade isolates found tended to form habitat-specific subclusters. The pufLM genes were detected in two groups of strains from dinoflagellate cultures but in none of the other Roseobacter clade isolates. Strains within the first group (the DFL-12 cluster) also synthesized Bchl a. Strains within the second group (the DFL-35 cluster) formed a new species of Roseovarius and did not produce Bchl a under the conditions investigated here, thus demonstrating the importance of genetic methods for screening of cultivation-dependent metabolic traits. The pufL genes of the dinoflagellate isolates were phylogenetically closely related to pufL genes from Betaproteobacteria, confirming similar previous observations which have been interpreted as indications of gene transfer events.
Gregory L. Challis - One of the best experts on this subject based on the ideXlab platform.
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Anti-microfouling Activity of Glycomyces sediminimaris UTMC 2460 on Dominant Fouling Bacteria of Iran Marine Habitats
Frontiers Media S.A., 2019Co-Authors: Sheida Heidarian, Fatemeh Mohammadipanah, Abdolvahab Maghsoudlou, Yousef Dashti, Gregory L. ChallisAbstract:Discovery of environmentally safe anti-fouling agent is currently of considerable interest, due to the continuous impact of biofoulers on the Marine Habitats and the adverse effects of biocides on the environment. This study reports the anti-adhesion effect of Marine living Actinobacteria against fouling strains isolated from submerged panels in Marine environments of Iran. The extract of Glycomyces sediminimaris UTMC 2460 affected the biofilm formation of Kocuria sp. and Mesorhizobium sp., as the dominant fouling agents in this ecosystem, up to 93.2% and 71.4%, respectively. The metabolic activity of the fouler bacteria was reduced by the extract up to 17 and 9%, respectively. This indicated the bactericidal potency of the extract on cells in the biofilm state that enables the compound to be effective even once the biofilms are established in addition to the inhibition of biofilm initiation. Moreover, extra polymeric substance (EPS) production by fouling bacteria was reduced by 60–70%. The absence of activities against fouling bacteria in suspension and also the absence of toxic effect on Artemia salina showed the harmless ecological effect of the anti-microfouling extract on the prokaryotic and eukaryotic microflora of the studied Iran Marine ecosystem. Metabolic profiling of G. sediminimaris UTMC 2460 revealed the presence of compounds with molecular formulae matching those of known anti-fouling diketopiperazines as major components of the extract. These results suggest that the extract of Glycomyces sediminimaris UTMC 2460 could be used as a potentially eco-friendly viable candidate in comparison to the synthetic common commercial anti-microfouling material to prevent the fouling process in Marine Habitats of Iran
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Data_Sheet_1_Anti-microfouling Activity of Glycomyces sediminimaris UTMC 2460 on Dominant Fouling Bacteria of Iran Marine Habitats.DOCX
2019Co-Authors: Sheida Heidarian, Fatemeh Mohammadipanah, Abdolvahab Maghsoudlou, Yousef Dashti, Gregory L. ChallisAbstract:Discovery of environmentally safe anti-fouling agent is currently of considerable interest, due to the continuous impact of biofoulers on the Marine Habitats and the adverse effects of biocides on the environment. This study reports the anti-adhesion effect of Marine living Actinobacteria against fouling strains isolated from submerged panels in Marine environments of Iran. The extract of Glycomyces sediminimaris UTMC 2460 affected the biofilm formation of Kocuria sp. and Mesorhizobium sp., as the dominant fouling agents in this ecosystem, up to 93.2% and 71.4%, respectively. The metabolic activity of the fouler bacteria was reduced by the extract up to 17 and 9%, respectively. This indicated the bactericidal potency of the extract on cells in the biofilm state that enables the compound to be effective even once the biofilms are established in addition to the inhibition of biofilm initiation. Moreover, extra polymeric substance (EPS) production by fouling bacteria was reduced by 60–70%. The absence of activities against fouling bacteria in suspension and also the absence of toxic effect on Artemia salina showed the harmless ecological effect of the anti-microfouling extract on the prokaryotic and eukaryotic microflora of the studied Iran Marine ecosystem. Metabolic profiling of G. sediminimaris UTMC 2460 revealed the presence of compounds with molecular formulae matching those of known anti-fouling diketopiperazines as major components of the extract. These results suggest that the extract of Glycomyces sediminimaris UTMC 2460 could be used as a potentially eco-friendly viable candidate in comparison to the synthetic common commercial anti-microfouling material to prevent the fouling process in Marine Habitats of Iran.
