scholarly journals Deep-sea scavenging amphipod assemblages from the submarine canyons of the Western Iberian Peninsula

2012 ◽  
Vol 9 (11) ◽  
pp. 4861-4869 ◽  
Author(s):  
G. A. Duffy ◽  
T. Horton ◽  
D. S. M. Billett

Abstract. Submarine canyons have often been identified as hotspots of secondary production with the potential to house distinct faunal assemblages and idiosyncratic ecosystems. Within these deep-sea habitats, assemblages of scavenging fauna play a vital role in reintroducing organic matter from large food falls into the wider deep-sea food chain. Free-fall baited traps were set at different depths within three submarine canyons on the Iberian Margin. Amphipods from the traps were identified to species level and counted. Scavenging amphipod assemblages were compared at different depths within each canyon and between individual canyon systems. Using data from literature, abyssal plain assemblages were compared to submarine canyon assemblages. Samples from canyons were found to contain common abyssal plain species but in greater than expected abundances. It is proposed that this is a result of the high organic carbon input into canyon systems owing to their interception of sediment from the continental shelf and input from associated estuarine systems. Community composition differed significantly between the submarine canyons and abyssal plains. The cause of this difference cannot be attributed to one environmental variable due to the numerous inherent differences between canyons and abyssal plains.

2012 ◽  
Vol 9 (6) ◽  
pp. 7831-7851 ◽  
Author(s):  
G. A. Duffy ◽  
T. Horton ◽  
D. S. M. Billett

Abstract. Submarine canyons have often been identified as hotspots of secondary production with the potential to house distinct faunal assemblages and idiosyncratic ecosystems. Within these deep-sea habitats, assemblages of scavenging fauna play a vital role in reintroducing organic matter from large food falls into the wider deep-sea food chain. Free-fall baited traps were set at different depths within three submarine canyons on the Iberian Margin. Amphipods from the traps were identified to species level and counted. Scavenging amphipod assemblages were compared at different depths within each canyon, between individual canyon systems, and between the abyssal plain and submarine canyon sites. Samples from canyons were found to contain common abyssal plain species but in greater than expected abundances. Community composition differed significantly between the submarine canyons and abyssal plains. It is proposed that this is a result of the high organic carbon input into canyon systems owing to their interception of sediment from the continental shelf and input from associated estuarine systems.


2021 ◽  
Vol 8 ◽  
Author(s):  
Iga-Maria Nestorowicz ◽  
Frederico Oliveira ◽  
Pedro Monteiro ◽  
Luís Bentes ◽  
Nuno Sales Henriques ◽  
...  

Identifying vulnerable marine habitats is fundamental to promote evidence-based management and a sustainable use of our oceans. Although progress in the mapping of marine benthic habitats has been made, complex ecosystems such as submarine canyons remain largely unexplored, hampering evidence-based management from taking place in these ubiquitous features worldwide. Data from a remotely operated vehicle (ROV) survey in the upper São Vicente Submarine Canyon in southwestern Portugal from 2011, was analysed to carry out a comprehensive assessment of megabenthic habitats, particularly those of conservation concern occuring between 90 and 560 m. Underwater videos from three exploratory dives, covering a total of 8.8 kilometers, were analyzed through multivariate and visual assessments, and the identified habitats were assessed against a set of criteria derived from current definitions of priority habitats. Thirteen potential priority habitats were characterized, out of which four distinct “coral gardens” and one “deep-sea sponge aggregation” are aligned with OSPAR definitions of priority habitats, and one corresponds to the habitat of a strictly protected sea urchin listed in the Habitats Directive. Three circalittoral sponge aggregations were also suggested based on the abundance of indicator species. The specific composition and diversity of priority habitats as described here, has not yet been described in any other canyon in the NE Atlantic region. Depth was revealed to be particularly important for the distribution of habitats, followed by relief and substratum. The approach presented in this study contributes to improve the understanding about submarine canyons, which is paramount to implement knowledge-based protection measures. Furthermore, it can be used to support future mapping efforts of deep-sea environments such as submarine canyons.


Mathematics ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 608
Author(s):  
Danielle Burton ◽  
Suzanne Lenhart ◽  
Christina J. Edholm ◽  
Benjamin Levy ◽  
Michael L. Washington ◽  
...  

The 2014–2016 West African outbreak of Ebola Virus Disease (EVD) was the largest and most deadly to date. Contact tracing, following up those who may have been infected through contact with an infected individual to prevent secondary spread, plays a vital role in controlling such outbreaks. Our aim in this work was to mechanistically represent the contact tracing process to illustrate potential areas of improvement in managing contact tracing efforts. We also explored the role contact tracing played in eventually ending the outbreak. We present a system of ordinary differential equations to model contact tracing in Sierra Leonne during the outbreak. Using data on cumulative cases and deaths, we estimate most of the parameters in our model. We include the novel features of counting the total number of people being traced and tying this directly to the number of tracers doing this work. Our work highlights the importance of incorporating changing behavior into one’s model as needed when indicated by the data and reported trends. Our results show that a larger contact tracing program would have reduced the death toll of the outbreak. Counting the total number of people being traced and including changes in behavior in our model led to better understanding of disease management.


Zootaxa ◽  
2019 ◽  
Vol 4688 (2) ◽  
pp. 249-263
Author(s):  
DANIEL LAURETTA ◽  
MARIANO I. MARTINEZ

Corallimorpharians are a relative small group of anthozoan cnidarians, also known as jewel sea anemones. They resemble actiniarian sea anemones in lacking a skeleton and being solitary, but resemble scleractinian corals in external and internal morphology, and they are considered to be the sister group of the stony corals. Corynactis carnea (=Sphincteractis sanmatiensis) is a small, common and eye catching species that inhabits the shallow water of northern Patagonia and the Argentinean shelf up to 200 m depth. Corallimorphus rigidus is registered for the first time from the southwestern Atlantic Ocean. It is a rather big and rare species that inhabits only the deep sea. Only two specimens were found at 2934 m depth in Mar del Plata submarine canyon, in an area under the influence of the Malvinas current, which may explain its occurrence. These two species are the only two known jewel sea anemones in the Argentinean sea and are reported and described herein. 


Author(s):  
Fabio C. De Leo ◽  
Jeffrey C. Drazen ◽  
Eric W. Vetter ◽  
Ashley A. Rowden ◽  
Craig R. Smith

2016 ◽  
Vol 124 (6) ◽  
pp. 1794-1804 ◽  
Author(s):  
Suzanne M. Michalak ◽  
John D. Rolston ◽  
Michael T. Lawton

OBJECT Surgery requires careful coordination of multiple team members, each playing a vital role in mitigating errors. Previous studies have focused on eliciting errors from only the attending surgeon, likely missing events observed by other team members. METHODS Surveys were administered to the attending surgeon, resident surgeon, anesthesiologist, and nursing staff immediately following each of 31 cerebrovascular surgeries; participants were instructed to record any deviation from optimal course (DOC). DOCs were categorized and sorted by reporter and perioperative timing, then correlated with delays and outcome measures. RESULTS Errors were recorded in 93.5% of the 31 cases surveyed. The number of errors recorded per case ranged from 0 to 8, with an average of 3.1 ± 2.1 errors (± SD). Overall, technical errors were most common (24.5%), followed by communication (22.4%), management/judgment (16.0%), and equipment (11.7%). The resident surgeon reported the most errors (52.1%), followed by the circulating nurse (31.9%), the attending surgeon (26.6%), and the anesthesiologist (14.9%). The attending and resident surgeons were most likely to report technical errors (52% and 30.6%, respectively), while anesthesiologists and circulating nurses mostly reported anesthesia errors (36%) and communication errors (50%), respectively. The overlap in reported errors was 20.3%. If this study had used only the surveys completed by the attending surgeon, as in prior studies, 72% of equipment errors, 90% of anesthesia and communication errors, and 100% of nursing errors would have been missed. In addition, it would have been concluded that errors occurred in only 45.2% of cases (rather than 93.5%) and that errors resulting in a delay occurred in 3.2% of cases instead of the 74.2% calculated using data from 4 team members. Compiled results from all team members yielded significant correlations between technical DOCs and prolonged hospital stays and reported and actual delays (p = 0.001 and p = 0.028, respectively). CONCLUSIONS This study is the only of its kind to elicit error reporting from multiple members of the operating team, and it demonstrates error is truly in the eye of the beholder—the types and timing of perioperative errors vary based on whom you ask. The authors estimate that previous studies surveying only the attending physician missed up to 75% of perioperative errors. By finding significant correlations between technical DOCs and prolonged hospital stays and reported and actual delays, this study shows that these surveys provide relevant and useful information for improving clinical practice. Overall, the results of this study emphasize that research on medical error must include input from all members of the operating team; it is only by understanding every perspective that surgical staff can begin to efficiently prevent errors, improve patient care and safety, and decrease delays.


1972 ◽  
Vol 28 (4) ◽  
pp. 153-160 ◽  
Author(s):  
J. J. Morley ◽  
K. W. Potter ◽  
Y. Iwabuchi ◽  
D. J. Elvers
Keyword(s):  
Deep Sea ◽  

2018 ◽  
Vol 168 ◽  
pp. 57-64 ◽  
Author(s):  
Giulio Barone ◽  
Eugenio Rastelli ◽  
Cinzia Corinaldesi ◽  
Michael Tangherlini ◽  
Roberto Danovaro ◽  
...  

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