Biological Oceanography Research Papers - Academia.edu (original) (raw)

This study focuses on the influence of extreme hydrological events on the water quality of the Strait of Istanbul (Bosphorus); a stratified waterway, polluted by sewage outfalls and non-point sources. Monthly collected water quality... more

- by and +1
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- Physical Oceanography, Biological Oceanography

Present short communication reports about beach stranding of Porpita porpita (Linnaeus 1758) from the Coast of Mandvi, Kutch during August 2021. Also, this is the first record of the blue button jellyfishes for the northern Gulf of Kutch region. A study was carried out by primary observation and measurements of common environmental parameters such as Sea Surface Temperature (SST), Wind Direction & Wind Speed. Aboral and oral parts were observed and described. It is assumed that the large biomass of blue button jellyfish on the beach is due to strong shoreward Monsoon winds.

- by Niki Rami
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- Marine Biology, Environmental Science, Climate Change, Marine Ecology
- by Sabine Cochrane
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- Zoology, Marine Ecology, Multidimensional Scaling, Biology

Comau Fjord is a stratified Chilean Patagonian Fjord characterized by a shallow brackish surface layer and a >400 m layer of aragonite-depleted subsurface waters. Despite the energetic burden of low aragonite saturation levels to calcification, Comau Fjord harbours dense populations of cold-water corals (CWC). While this paradox has been attributed to a rich supply of zooplankton, supporting abundance and biomass data are so far lacking. In this study, we investigated the seasonal and diel changes
of the zooplankton community over the entire water column. We used a Nansen net (100 mm mesh) to take stratified vertical hauls between the surface and the bottom (0-50-100-200-300-400-450 m). Samples were scanned with a ZooScan, and abundance, biovolume and biomass were determined for 41 taxa identified on the web-based platform EcoTaxa 2.0. Zooplankton biomass was the highest in summer (209 g dry massm􀀀2) and the lowest in winter (61 g dry massm􀀀2). Abundance, however, peaked in spring, suggesting a close correspondence between reproduction and phytoplankton spring blooms (Chl a max. 50.86 mgm􀀀3, 3mdepth). Overall, copepods were the most important group of the total zooplankton community, both in abundance (6481%) and biovolume (2070%) followed by mysids and chaetognaths (in terms of biovolume
and biomass), and nauplii and Appendicularia (in terms of abundance). Throughout the year, diel changes in the vertical distribution of biomass were found with a daytime maximum in the 100200 m depth layer and a nighttime maximum in surface waters (050 m), associated with the diel vertical migration of the calanoid copepod family Metridinidae. Diel differences in integrated zooplankton abundance, biovolume and
biomass were probably due to a high zooplankton patchiness driven by biological processes (e.g., diel vertical migration or predation avoidance), and oceanographic processes (estuarine circulation, tidal mixing or water column stratification). Those factors are considered to be the main drivers of the zooplankton vertical distribution in Comau Fjord.

- by Juan Hofer
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- Marine Ecology, Zooplankton ecology, Biological Oceanography, Patagonia
- by Stephen Lamberth
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- Zoology, Earth Sciences, Microbial Ecology, Ecology

This study was originally submitted as a dissertation for the doctoral degree in Marine Sciences for the Department of Marine Sciences of the University of Puerto Rico at Mayagüez. It was subdivided into eleven chapters and two appendixes, which treated a number of biological aspects of the coastal, marine, and estuarine mycology of the Puerto Rican archipelago. Field and laboratory surveys were carried out. It has been summarized the history of marine mycology in Puerto Rico, a checklist of all the known fungi species, and general ecological aspects in beaches, mangroves, and estuarine environments. Some fungal species might be useful for bioremediation. For example, two species of Cladosporium were isolated from seawater based on their ability to use the polyaromatic hydrocarbons naphthalene and phenanthrene as a sole carbon and energy source. Also a bibliography on coastal and marine biology primarily mycological in orientation is presented.

- by Ángel M . Nieves-Rivera, Ph.D.
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- Marine Biology, Oceanography, Mangroves, Puerto Rico

Descripción del curso Describir las propiedades o factores (temperatura, salinidad, presión, luz, nutrientes,) y procesos que afectan la vida en el océano, mediante la comparación con la vida en tierra o agua dulce, para comprender como determinan los patrones de distribución y abundancia de los organismos marinos (biogeografía marina). Además se realiza una revisión del conocimiento actual de los procesos ecológicos en el ecosistema marino. Finalmente se analizan los ecosistemas o sub-ecosistemas y sus retroalimentaciones positivas y negativas con la civilización humana. El objetivo del curso es realizar una revisión del conocimiento actual en ecología, dinámica de poblaciones y comunidades, biodiversidad y cambios en el hábitat marino. Se enfatizan los procesos que definen los patrones de distribución y abundancia de los organismos en el océano, con el fin de identificar áreas de oportunidad para realizar investigación o estudios. Desarrolla la capacidad de integración del conocimiento multidisciplinario y las habilidades de trabajo interdisciplinario necesarias en el campo de la oceanografía biológica y ecología marina. .

Knowledge about deep sea, abysmal high kinetic energy current and eddie events known as benthic storms has traditionally been very limited in science. However, recent studies have popularized knowledge of its existence and uncovered that although rare, instances and occurrences of this phenomenon have major effects on the sea floor that create significant disturbances which can lead to changes in the entire topography and biodiversity demographics of the benthic sediment ecosystem.

- by Calvin Zerry
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- Oceanography, Biological Oceanography, Deep sea ecology, Weather

A large patch of anomalously warm water (nicknamed “the Blob”) appeared off the coast of Alaska in the winter of 2013–2014 and subsequently stretched south to Baja California. This northeastern Pacific warm-water anomaly persisted through the end of 2015. Scientists and the public alike noted widespread changes in the biological structure and composition of both open ocean and coastal ecosystems. Changes included geographical shifts of species such as tropical copepods, pelagic red crabs, and tuna; closures of commercially important fisheries; and mass strandings of marine mammals and seabirds. The
ecological responses to these physical changes have been sparsely quantified and are largely unknown. Here, we provide a bottom-up summary of some of the biological changes observed in and around the areas affected by the Blob.

- by Arturo Ramirez-Valdez
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- Oceanography, Phytoplankton Ecology, Marine Mammals, Zooplankton ecology

Se analizó la distribución de la abundancia, biomasa, número de especies y diversidad del macrozoobentos de fondo blando en la ensenada de Sechura, Piura,ubicada entre los 5°12´ y 5°50´ de Latitud Sur y 81°12’ y 80°51´ de Longitud Oeste,... more

Anti-inflammatory, anti-oxidant, anti-cancerous, radioprotective and
anti-microbial properties of ginger (Zingiber officinale) rhizome are
well recognized worldwide. Ginger consumption also helps in the
management of inflammatory damage in Alzheimer’s and
Parkinson’s disease. Biological properties of ginger rhizome are
attributed to its active compounds including, gingerols, shogaols,
paradols and zingerone. Zingerone is active component of dried
ginger rhizome and used in food industry as flavouring agent.
Various observations on the protective role of zingerone against
radiation induced oxidative stress; tissue inflammatory damage and
drug induced toxicity have been made using a wide range of
experimental models. Mechanism of antioxidant and antiinflammatory action of zingerone has been linked to potent radical
scavenging effect, causing alteration in gene/protein expression and
interference with intracellular cell signalling pathways of
inflammation. Our laboratory for the first time revealed antibiofilm
activity of zingerone against opportunistic pathogen Pseudomonas
aeruginosa. This study suggested that zingerone can be explored as a
safe anti-infective agent against P. aeruginosa biofilm associated
infections. Hence, comprehensive information showing health
benefits of zingerone are urgently needed that may provide an update
on its therapeutic potential. We conducted a detailed search of
literature to summarize the proven health benefits and biological
properties of zingerone. This review article summarizes in detail the
in vitroand in vivopharmacological benefits of zingerone.

- by Md. Sazzadur Rahaman
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- Biological Oceanography

A new textbook Physical Oceanography: A short course for beginners by Y. D. Afanasyev is now available from CreateSpace eStore: https://www.createspace.com/6426337
(and from Amazon). ISBN-13: 978-1535312387
Oceanography is a vast science, and beginners often feel overwhelmed by the number and variety of different topics. This book presents a distilled version of physical oceanography by providing physical insight into the circulation of the Earth’s oceans. A consistent view of the circulation is presented using only simple mathematics and an intuitive approach; however, hints to various phenomena are given for those who are willing to explore beyond this book. The book also contains an elementary introduction to fluid mechanics.

- by Yakov Afanasyev
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- Ocean Engineering, Oceanography, Physical Oceanography, Biological Oceanography

Machine learning (ML) is a subset of artificial intelligence that enables to take decision based on data. Artificial intelligence makes possible to integrate ML capabilities into data driven modelling systems in order to bridge the gaps and lessen demands on human experts in oceanographic research .ML algorithms have proven to be a powerful tool for analysing oceanographic and climate data with high accuracy in efficient way. ML has a wide spectrum of real time applications in oceanography and Earth sciences. This study has explained in simple way the realistic uses and applications of major ML algorithms. The main application of machine learning in oceanography is prediction of ocean weather and climate, habitat modelling and distribution, species identification , coastal water monitoring, marine resources management, detection of oil spill and pollution and wave modelling.

- by Armando Marques-Guedes
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- History, Oceanography, Economics, Anthropology

In this thrilling adventure tale by the father of science fiction, three men embark on an epic journey under the sea with the mysterious Captain Nemo aboard his submarine, the Nautilus. Over the course of their fantastical voyage, they encounter the lost city of Atlantis, the South Pole, and the corals of the Red Sea. Along the way, they must battle countless adversaries both human and monstrous. This triumphant work of the imagination shows the limitless possibilities of science and the dark depths of the human mind.

- by David Vanderper
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- Non Fiction Writing, Mythology And Folklore, History, Oceanography
- by Stephen Lamberth
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- Zoology, Earth Sciences, Microbial Ecology, Ecology

Sound is the primary sensory modality for dolphins, yet policies mitigating anthropogenic sound exposure are limited in wild populations and even fewer noise policies or guidelines have been developed for governing dolphin welfare under human care. Concerns have been raised that dolphins under human care live in facilities that are too noisy, or are too acoustically sterile. However, these claims have not been evaluated to characterize facility soundscapes, and further, how they compare to wild soundscapes. The soundscape of a wild dolphin habitat off the coast of Quintana, Roo, Mexico was characterized based on Passive Acoustic Monitoring (PAM) recordings over one year. Snapping shrimp were persistent and broadband, following a diel pattern. Fish sound production was pulsed and prominent in low frequencies (100 -- 1000 Hz), and abiotic surface wave action contributed to noise in higher frequencies (15 -- 28 kHz). Boat motors were the main anthropogenic sound source. While sporadic, boat motors were responsible for large spikes in the noise, sometimes exceeding the ambient noise (in the absence of a boat) by 20 dB root-mean-squared sound pressure level, and potentially higher at closer distances. Boat motor sounds can potentially mask cues and communication sounds of dolphins. The soundscapes of four acoustically distinct outdoor dolphin facilities in Quintana Roo, Mexico were also characterized based on PAM, and findings compared with one another and with the measurements from the wild dolphin habitat. Recordings were made for at least 24 hours to encompass the range of daily activities. The four facilities differed in non-dolphin species present (biological sounds), bathymetry complexity, and method of water circulation. It was hypothesized that the greater the biological and physical differences of a pool from the ocean habitat, the greater the acoustic differences would be from the natural environment. Spectral analysis and audio playback revealed that the site most biologically and physically distinct from the ocean habitat also differed greatly from the other sites acoustically, with the most common and high amplitude sound being pump noise versus biological sounds at the other sites. Overall the dolphin facilities were neither clearly noisier nor more sterile than the wild site, but rather differed in particular characteristics. The findings are encouraging for dolphin welfare for several reasons. Sound levels measured were unlikely to cause threshold shifts in hearing. At three of four facilities, prominent biological sounds in the wild site -- snapping shrimp and fish sounds -- were present, meaning that the dolphins at these facilities are experiencing biotic features of the soundscape they would experience in the wild. Additionally, the main anthropogenic sounds experienced at the facilities (construction and cleaning sounds) did not reach the levels of the anthropogenic sounds experienced at the wild site (boat motor sounds), and the highest noise levels for anthropogenic sounds fall outside the dolphins' most sensitive range of hearing. However, there are anthropogenic contributors to the soundscape that are of particular interest and possible concern that should be investigated further, particularly pump noise and periodic or intermittent construction noise. These factors need to be considered on a facility-by-facility basis and appropriate mitigation procedures incorporated in animal handling to mitigate potential responses to planned or anticipated sound producing events, e.g. animal relocation or buffering sound producing activities. The central role of bioacoustics for dolphins means that PAM is a basic life support requirement along with water and food testing. Periodic noise is of highest concern, and PAM is needed to inform mitigation of noise from periodic sources. Priority actions are more widespread and long-term standardized monitoring, further research on habituation, preference, coupling and pool acoustics, implementation of acoustics training, standardization of measurements, and improved information access.

- by Heather Spence
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- Marine Biology, Acoustics, Bioacoustics, Conservation Biology
- by Prottasha Tahmida
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- Oceanography, Physical Oceanography, Biological Oceanography
- by Sonia Tiquia-Arashiro
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- Biological Oceanography
- by Anita Pahlewi
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- Biological Oceanography

Marine plastic debris floating on the ocean surface is a major environmental problem. However, its distribution in the ocean is poorly mapped, and most of the plastic waste estimated to have entered the ocean from land is unaccounted for. Better understanding of how plastic debris is transported from coastal and marine sources is crucial to quantify and close the global inventory of marine plastics, which in turn represents critical information for mitigation or policy strategies. At the same time, plastic is a unique tracer that provides an opportunity to learn more about the physics and dynamics of our ocean across multiple scales, from the Ekman convergence in basin-scale gyres to individual waves in the surfzone. In this review, we comprehensively discuss what is known about the different processes that govern the transport of floating marine plastic debris in both the open ocean and the coastal zones, based on the published literature and referring to insights from neighbouring fields such as oil spill dispersion, marine safety recovery, plankton connectivity, and others. We discuss how measurements of marine plastics (both in situ and in the laboratory), remote sensing, and numerical simulations can elucidate these processes and their interactions across spatio-temporal scales.

- by Giuseppe Suaria and +2
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- Oceanography, Physical Oceanography, Biological Oceanography, Microplastics in the Oceans

El Delta del Río Colorado ha sido objeto de estudios multidisciplinarios en el Proyecto Delta Camarón del Instituto de Investigaciones Oceanológicas de la UABC. Como resultado de estos es evidente que la region es extremadamente productiva con valores de clorofila entre 2 a 5 mg/m 3 y biomasas de zooplankton entre 1 a 154 mg/m 3. Correspondientemente los valores de materia orgánica en el sedimento se encuentra el 5 al 9%. Este medio ambiente genera una cadena trófica muy activa con altas biomasas de consumidores radicada en poblaciones muy densas de especies de biomasa individual alta, como Uca princeps que presenta hasta 89.981 gr/m 2. Otras especies pueden ser importantes, aunque no se ha medido todavia su biomasa estas son Callinectes arcuatus, Chione cortezi y Penaeus stilyrostris. Estas especies a excepción de Chione cortezi se alimentan de la producción bentónica. La biomasa de peces esta dominada por Micropogonias stenops el cual se alimenta primordialmente de organismos bentónicos. Por lo tanto se plantea la hipótesis que la via detrítica se la cadena es la dominante en el delta del Colorado.

The southeast region of the Gulf of Mexico is considered to be biologically important, because it is a connection and
transition zone between the Caribbean and the Gulf of Mexico, harboring great marine biodiversity. Nevertheless, benthic
amphipods have been poorly studied in the Mexican southeast sector of the Gulf of Mexico with few studies listing
species. The aim of this study is to provide an update checklist of species for the Mexican southeast sector (based on
literature review and records from the present study) as well as a brief zoogeographical analysis for the Gulf of Mexico
amphipod fauna, putting them in context with the fauna on the tropical western Atlantic. Fifty-five species were listed for
the Mexican southeast sector; 36 of them showed a geographical extension to the Yucatan continental shelf representing
23 new records for the Mexican southeast sector, nine for the southeast region and four for the Gulf of Mexico. Based on
the zoogeographical analysis, there is support of the application of Carolinian and Caribbean zoogeographic provinces to
amphipods in the Gulf of Mexico

- by Carlos E. Paz Ríos and +1
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- Taxonomy, Marine biodiversity, Biogeography, Biological Oceanography

Zooplankton plays an important role in the biogeochemical cycles in the ocean. Due to their central position in the ocean’s food web, they recycle and redistribute energy and matter, not only at different levels of the trophic web, but also horizontally and vertically in the water column. Understanding the role of zooplankton in the biological pump and the ocean carbon cycle requires accurate estimates of community biomass and metabolism at large spatial scales. Measurements of the former are relatively affordable. However, traditional methods to estimate metabolism are highly time- consuming processes, preventing its use over large study regions. Similarly, enzymatic methods, although useful, show uncertainties to approach metabolic rates from enzymatic activity. In this thesis we developed and tested alternative tools to assess zooplankton biomass and metabolic fluxes at large spatial and temporal scales. Thus, we examined the suitability of image-based systems (IBS), combined with empirical relationships and metabolic equations, to estimate biomass and metabolism of zooplankton on subtropical regions. We observed that these procedures could be as reliable as traditional and enzymatic methods when equations fitted the conditions of the subtropical region, although the former resulted in a faster and inexpensive process, among other advantages. Nevertheless, enzymatic methods seemed to be a better alternative to assess specific metabolic rates on particular studies, such as those on temporal-series.
The reliability of IBS to study zooplankton was also ascertained along physical structures in a region with a high mesoscale activity near the Canary Islands. Here, we observed a physical-biological coupling, since the distribution of biomass and metabolism of zooplankton matched the three- dimensional signature of the oceanographic structures. Then, based on the results achieved using the IBS on subtropical waters, we developed specific equations for growth and respiration of zooplankton, fitted to the temperature ranges of the main regions of the global ocean. Thus, comparing equations and methods along the ~40oN-40oS latitudinal band, we observed that estimates using these temperature-specific equations were comparable to those from enzymatic methods, and probably more accurate than using existing generalist relationships for the global ocean.
Given their usefulness, we finally applied these temperature-specific metabolic equations to study active fluxes through zooplankton in the tropical and subtropical Atlantic (10oS-25oN). We highlight the contribution of zooplankton export to the biological pump, and the importance of addressing studies assessing active fluxes through mortality, but also due to egestion and ammonia excretion processes. Additionally, we illustrate the future possibilities of predicting zooplankton export using remote sensing data.

- by Maycira Costa
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- Oceanography, Remote Sensing, Marine Science, Biological Oceanography

The long-term vision that has underlain the proposal to IMOS for the “Radiometry Task Team” (RTT), whose work is summarised in this report, is as follows.
We think that the Australian research community involved into ocean colour and bio-optics science has the potential to become a major player in the Southern hemisphere in the coming years. We want to play this role by providing crucial validation data to the upcoming global satellite missions (Sentinels in particular), by delivering satellite products tailored to the needs of Australian researchers, institutions and users, and by improving practices and knowledge of our community in the domain of fieldwork in optics.
The Australian Government has now an agreement with the European Commission (EC), signed by Geosciences Australia (GA) on hosting the collaborative Ground Segment for the Sentinel system. This agreement was, amongst other reasons, reached on the understanding that Australia would deliver world-class calibration –validation data back to the EC, the European Space Agency (ESA) and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT).
This will be feasible by building on the investments of the past 10 years, by taking advantage of the next slice of NCRIS funding to leverage co-contributions, and also by reorganizing significantly our assets and activities. International engagement will also be key to success here, for instance through the validation teams of global mission, the IOCCG, the building of international research proposals.
We hope that the present report shows how the RTT has achieved a first step in that direction and, above all, has allowed a community plan to be put together for the coming years.

- by Dr. Bruri Melky Laimeheriwa
- •
- Biological Oceanography

The Gulf of California has one of the most diverse ichthyofauna in the region of the Eastern Pacific. Between 850 to 900 species have been described within its different environments. The Gulf of California also shows an endemism of almost 10% of the total number of species. For this reason the Gulf of California has been considered as a biogeographic province apart from the Mexican Province, which is located to the south. It is also a key region from the biogeographic point of view in order to understand the processes and causes of fish distribution.

- by Raymundo Avendaño-Ibarra
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- Fish Biology, Biological Oceanography, Fish Larvae
- by iqbal aditya
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- Biological Oceanography

Snake Island is an uninhabited small rocky islet off Carbyn’s Cove in Port Blair, Andaman. The biodiversity of this rocky island is its distinctive feature as it becomes a small habitat for various organisms close to the open sea. During this present study a total no. of 217 species were recorded out of which 205 has been identified. Pisces was the dominant group, followed by cnidarians, molluscs, arthropods etc. The island is highly influenced by sea water as during high tides nearly 75 % of the island is submerged by seawater. This is the reason of dominance of marine organisms (94 %) over terrestrial organisms (6 %) in the island. Another characteristic feature of the island is the formation of numerous rocky and sandy water channels and the presence of a ‘coral pool’ at the end of one such channel on the north-eastern part of the island. During high tide these channels are filled with water and exchange of seawater takes place in the coral pool, where highest diversity of species was observed. Lack of intertidal species in the island is evident due to the high action of waves from the open sea and lack of hiding areas other than rocky crevices. Get more articles at: http://www.innspub.net/volume-6-number-4-april-2015-jbes/

Chaetognaths are important members of Arctic mesozooplankton communities in terms of abundance and biomass. Despite this, the bulk of seasonal studies have focused on grazing copepods. Arctic chaetognaths comprise three major species which are thought to be strict carnivores: Eukrohnia hamata, Parasagitta elegans and Pseudosagitta maxima. This thesis uses datasets collected from plankton net sampling during five years in European, Canadian and Alaskan areas of the Arctic (2007, 2008, 2012, 2013, 2014) and includes a full annual cycle in the Canadian Arctic (2007-2008), the purpose being to improve our understanding of the distributions, life history and feeding strategies of E. hamata and P. elegans. The following topics are addressed: (1) the feeding strategy and maturity of P. elegans in the European Arctic during the polar night in 2012 and 2013; (2) the growth, breeding cycles, feeding strategies and vertical distributions of E. hamata and P. elegans, in the Canadian Arctic from 2007 to 2008; and (3) spatial differences in the feeding strategies of E. hamata and P. elegans in autumn 2014. To investigate feeding strategies, a combination of gut contents and biochemical techniques was used. In the Canadian Arctic, both E. hamata and P. elegans live for around 2 years. P. elegans mainly colonized epi-pelagic waters, whereas E. hamata mainly colonized meso-pelagic waters. In this region, P. elegans reproduced continuously from summer to early winter when copepod prey peak in near-surface waters. This is characteristic of income breeders. However, results for E. hamata revealed that this species spawned distinct and traceable broods during separate reproductive windows in both spring-summer and autumn-winter, suggesting capital breeding. Daily predation rates inferred from gut content analyses appeared to be generally low in the two chaetognath species, though inferred predation rates in summer-autumn exceeded those in winter-spring. Feeding studies revealed that E. hamata consumed particulate organic matter (possibly falling marine snow) throughout the year but especially in the summer, whereas P. elegans did not feed in this way. High summer growth seems to be a characteristic of both these species. Growth during winter was highly restricted in P. elegans, to a lesser extent in E. hamata. In summary, differences in how lipids and marine snow are utilised by the two species could explain differences in their breeding cycles and seasonal growth patterns.

- by Jordan Grigor
- •
- Marine Biology, Zoology, Environmental Science, Oceanography

Biomass, diversity, composition and taxonomic structure of phytoplankton in the Pacific Ocean of Colombia were studied
during Pacific XXXIX-ERFEN XXXVII oceanographic survey. The operative plan of sampling was structured along 40 stations in the
Pacific Ocean of Colombia. Discrete sampling of phytoplankton was carried out by oblique trawling with standard phytoplankton
net (60μm) in the 25 biological stations. Furthermore, chlorophyll-a concentration at standard depth in each biological stations
were estimated by spectrophotometry technique. 126 morph species of phytoplankton, belong to 37 genera, were identified.
The Diatom’s genera: Chaetoceros, Coscinodiscus, Thalassionema, Bacteriastrum, Rhizosolenia, Ditylum, Skeletonema, Nitzschia and Pseudonitzschia, were the dominant, following by Dynoflagelate´s genera: Ceratium, Ornithocercus, Pyrophacus, Protoperidinium, Dinophysis, Ceratocorys, Gonyaulax, Podolampas and Amphisolenia. This last taxonomic group trend to increase their abundance in the oceanic zone. Chlorophyll-a concentration was homogenous in the study area, ranged between 11.37 mgm-2 to 38.05 mgm-2 (integrate from 50 to 0m). Moreover, two centers of high Chlo-a concentration were identified: zone in the northern sector of oceanic zone (station 75) and the other one in the northern sector of coastal zone (Station 12). Diversity index of Shannon (H’) and richness of Hill’s numbers (N0 y N1) were higher in costal zone that oceanic zone

- by Julie Sandell
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- Biological Oceanography

The article looks at B.R. 84, a map produced by the British Admiralty showing the position of British cargo ships on March 7, 1936. Particular focus is given to its use in the book "The Ecology of Invasions" by scientist Charles Elton to illustrate the spread of invasive species through ocean-going vessels. According to the author, the map was actually designed to show the global economic reach of the British Empire.

- by Matt Chew
- •
- Oceanography, Philosophy of Science, Globalization, British History

Utility leaders worldwide face multiple challenges to secure
a reliable, efficient and sustainable future water supply – from
accelerated population growth, to exhaustion of our traditional
water sources, water scarcity driven by climate change and
inefficient management of our available water resources. Finding
a rational solution for sustainable water supply compels us to seek
new water management solutions based on:
• Adopting the wider use of alternative water resources
such as desalination of sea and brackish water
• Driving down the barriers for low energy desalination
• Extracting valuable resources (such as minerals and rare
metals) from the waste streams generated during the water
treatment processes, and
• Increasing reliance on renewable energy sources.

Every year, vast quantities of plastic debris arrive at the ocean surface. Nevertheless, our understanding of plastic movements is largely incomplete and many of the processes involved with the horizontal and vertical displacement of plastics in the ocean are still basically unknown. In this chapter we review the dynamics associated with the transport of plastics and other pollutants at oceanic fronts. Fronts had been historically defined as simple barriers to exchange, but here we show that the role of these structures in influencing the transport of plastics is more complex. The tools used to investigate the occurrence of frontal structures at various spatial scales are reviewed in detail, with a particular focus on their potential applications to the study of plastic pollution. Three selected case studies are presented to better describe the role of fronts in favoring or preventing plastic exchanges: the large-scale Antarctic Circumpolar Current, a Mediterranean mesoscale front, and the submesoscale fronts in the Gulf of Mexico. Lastly, some aspects related to the vertical subduction of plastic particles at oceanic fronts are discussed as one of the most promising frontiers for future research. The accumulation of floating debris at the sea surface is mainly affected by the horizontal components of frontal dynamics. At the same time, vertical components can be relevant for the export of neutrally buoyant particles from the surface into the deep sea. Based on these evidences, we propose that submesoscale processes can provide a fast and efficient route of plastic transport within the mixed layer, while mesoscale instabilities and associated vertical velocities might be the dominant mechanism to penetrate the deeper ocean on slower but broader scales. We conclude that given the ubiquitous presence of fronts in the world’s ocean, their contribution to the global plastic cycle is probably not negligible and the role of these processes in vertically displacing neutrally buoyant microplastics should be investigated in more detail.

- by Giuseppe Suaria
- •
- Oceanography, Physical Oceanography, Biological Oceanography, Marine Litter