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Life in the “Plastisphere”

Life in the Plastisphere (Author: Erik Zettler)

In a study recently published online in Environmental Science & Technology, the scientists say the plastisphere represents a novel ecological habitat in the ocean and raises a host of questions: How will it change environmental conditions for marine microbes, favoring some that compete with others? How will it change the overall ocean ecosystem and affect larger organisms? How will it change where microbes, including pathogens, will be transported in the ocean?

The collaborative team of scientists—Erik Zettler from Sea Education Association (SEA), Tracy Mincer from Woods Hole Oceanographic Institution (WHOI), and Linda Amaral-Zettler from the Marine Biological Laboratory (MBL), all in Woods Hole, Mass.—analyzed marine plastic debris that was skimmed with fine-scale nets from the sea surface at several locations in the North Atlantic Ocean during SEA research cruises. Most were millimeter-sized fragments.

Using scanning electron microscopy and gene sequencing techniques, they found at least 1000 different types of bacterial cells on the plastic samples, including many individual species yet to be identified. They included plants, algae, and bacteria that manufacture their own food (autotrophs), animals and bacteria that feed on them (heterotrophs), predators that feed on these, and other organisms that establish synergistic relationships (symbionts). These complex communities exist on plastic bits hardly bigger than the head of a pin, and they have arisen with the explosion of plastics in the oceans in the last 60 years.

These communities are likely different from those that settle on naturally occurring floating material such as feathers, wood, and microalgae, because plastics offer different conditions, including the capacity to last much longer without degrading.

The plastic debris also represents a new mode of transportation, acting as rafts that can convey harmful microbes, including disease-causing pathogens and harmful algal species. One plastic sampled they analyzed was dominated by members of the genus Vibrio, which includes bacteria that cause cholera and gastrointestinal maladies.
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Warming Oceans Are Reshaping Fisheries

Warming oceans are reshaping fisheries

For the first time, scientists have shown that ocean warming has had a global impact on the mix of species caught by fishermen. Previous studies indicated that some species are shifting location in response to temperature increases, with fish gradually moving away from the equator into cooler waters. However, research published in May 2013 in Nature shows that species from warmer waters have also been replacing those traditionally caught in many fisheries worldwide at least since 1970.

Study Methods

Dr. William Cheung of the University of British Columbia and his co-authors used the temperature preferences of fish caught around the world to determine the relationship between fisheries catch and ocean warming. They first assembled data on the distribution of 990 marine fish and invertebrates. They assigned each species a temperature preference based on the average sea surface temperature in areas where that species was predicted to have occurred between 1970 and 2000. Next, to measure changes in the composition of marine fisheries, the researchers compiled data on the tonnage of each species caught in the 52 marine ecosystems that account for most of the world’s fisheries. Then, for each ecosystem and each year from 1970 to 2006, they calculated the average temperature preference of the species, weighted by the amount caught. Finally, the researchers determined the connection between ocean warming and changes in fisheries catch by using a statistical model that separates out other factors, such as fishing effort and oceanographic variability.

Results
The authors found that, except in the tropics, catch composition in most ecosystems slowly changed to include more warm-water species and fewer cool-water species. In the tropics, the catch followed a similar pattern from 1970 to 1980 and then stabilized, likely because there are no species with high enough temperature preferences to replace those that declined. Statistical models showed that the increase in warm-water species was significantly related to increasing ocean temperatures.

Study citation
Cheung, W.W.L., R. Watson and D. Pauly. 2013.
Signature of ocean warming in global fisheries catch.
Nature. DOI: 10.1038/nature12156

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Cutting Specific Pollutants Would Slow Sea Level Rise, Research Indicates

coastal areas

The research team found that reductions in four pollutants that cycle comparatively quickly through the atmosphere could temporarily forestall the rate of sea level rise by roughly 25 to 50 percent.

The study, a collaboration of the Scripps Institution for Oceanography, NCAR, and Climate Central, is being published this week in the journal Nature Climate Change.

The potential impact of rising oceans on populated areas is one of the most concerning effects of climate change. Many of the world’s major cities, such as New York, Miami, Amsterdam, Mumbai, and Tokyo, are located in low-lying areas by the water.

Despite the risks, policy makers have been unable to agree on procedures for reducing emissions of carbon dioxide. With this in mind, the research team focused on emissions of four other heat-trapping pollutants: methane, tropospheric ozone, hydrofluorocarbons, and black carbon. These gases and particles last anywhere from a week to a decade in the atmosphere, and they can influence climate more quickly than carbon dioxide, which persists in the atmosphere for centuries.

If society were able to substantially reduce both emissions of carbon dioxide as well as the four other pollutants, total sea level rise would be lessened by at least 30 percent by 2100, the researchers concluded.

The study was funded by the National Science Foundation and the Department of Energy.

(Full New from Sience News)

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The Natural Ecosystems in the Colombian Orinoco Basin Are in Danger

Natural Ecosystems in Colombian Orinoco Basin in Danger

The Orinoco River flows from the Andesin Colombia to the Atlantic in Venezuela. The area of the basin includes landscapes of the Andes, plains of the Llanos and the Guiana shield. Orinoco’s tributary rivers form a basin considered to be the 3rd most important river system on the planet, and one of the most biologically diverse areas of the world.

Just recently the Ministry of Environment passed a decree to standardize the Protected Area categories and to organize the National System of Protected Areas. More than 100 protected areas and more than 100 indigenous reserves have been established in the Colombian Orinoco Basin over the last six decades. However, the only strictly protected areas in Colombia are the National Natural Parks System Areas, which protect only 10% of the area of natural ecosystems and less than 50% of the natural ecosystems in the Basin. Indigenous Reserves help significantly in the conservation of the natural ecosystems in the Basin, but are not a Protected Area category, making it difficult for indigenous groups to assist with natural conservation in Colombia.

Although the protected area has almost doubled, ecosystem protection does not increase proportionally, which is a sign of the lack of planning and management capacities of the regional and local governments that established most of these areas. Urgent actions should be taken to ensure protection of the natural ecosystems of high conservation value, as these may be significantly endangered. It is possible that more than 22,350 km² of natural savannas will be lost over the next 10 years, and effective counter measures are necessary now to prevent losing these biodiversity hotspots forever.

(Full New from Science News)

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Mediterranean blue economy: enhancing marine and maritime cooperation

Mediterranean Blue Economy
The European Investment Bank, in collaboration with the European Commission and the International Maritime Organisation , announce the 12th FEMIP Conference which will take place on 18 and 19 April at the Megaron Athens International Conference Centre in Athens.

This high-level forum will provide an opportunity, through targeted stakeholder roundtables, to discuss:

· Starting-up maritime clusters and promoting networking across training institutes
· Bridging the gap towards effective safety and surveillance
· Addressing synergies across projects and opportunities for development and investment

Key speakers will include Philippe de Fontaine Vive, Vice-President of the European Investment Bank, Maria Damanaki, Commissioner for Maritime Affairs and Fisheries, and Andrew Winbow, Assistant Secretary-General of the International Maritime Organisation.

Official Website

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Robotic fish navigate flowscapes

robotic fish
The EU funded European research project FILOSE has developed robots with a new sense – lateral line sensing. All fish have this sensing organ but so far it had no technological counterpart on man-made underwater vehicles.

In an article published in Proceedings of the Royal Society A, FILOSE team members describe a robotic fish that is controlled with the help of lateral line sensors. During the last 4 years, the FILOSE collaboration has investigated fish lateral line sensing and locomotion with the aims of understanding how fish detect and exploit flow features, and of developing efficient underwater robots based on biological principles.

Experiments with flow sensing and actuation in FILOSE have demonstrated that a fish robot can save energy by finding energetically favorable regions in the flow where the currents are weaker or by interacting with eddies so that they help to push the robot forward. The robots are also able to detect flow direction and swim upstream or hold station in the flow while compensating for the downstream drift by measuring the flow speed.

The lateral line sensing fish robots have been a joint effort of experts in fish biology (University of Bath, UK), underwater robotics (Tallinn University of Technology, Estonia), mechanical engineering (Riga Technical University, Latvia), signal analysis and flow perception (Verona University, Italy) and of sensor technology (Italian Institute of Technology).

More information

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Scientists solve 30-year mystery of the deep

Seals with transistors

Scientists, with the help of seals, have solved a 30-year mystery surrounding the formation of the global ocean’s coldest, deepest waters.

Until now they had known that the cold, dense bottom waters of the global ocean originated at three different locations in Antarctica – the Weddell Sea, the Ross Sea and the Adélie Coast of East Antarctica. Thirty years ago, a fourth source was speculated to exist somewhere in the Prydz Bay region, but until now scientists have been unable to confirm if, where and how it is being formed.

The research is published today in the journal Nature Geoscience. Its significance is underlined by the fact that Antarctic bottom water is a key driver of the global ocean circulation and therefore of the earth’s climate.

The newly identified source is different from the other three sources. Its existence demonstrates that polynyas (areas of open water surrounded by sea ice) are capable of forming sufficiently dense shelf water over a narrow section of continental shelf without the traditional assistance of a large ice shelf or coastal storage volume. This opens the door for further discoveries of Antarctic bottom water production from the other polynya regions around the Antarctic coastline.


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Seasonal input of regulated and emerging organic pollutants through surface watercourses to a Mediterranean coastal lagoon

Chemosphere

Seasonal input of organic pollutants through El Albujón Watercourse to the Mar Menor lagoon was estimated from Spring 2009 to Winter 2010, including regular periods and two flash flood events. 82 semivolatile organic pollutants (persistent organic pollutants, different groups of pesticides and others) were determined by stir bar sorptive extraction and thermal desorption followed by capillary gas chromatography coupled to mass spectrometry from surface waters with quantification limits of a few ng L−1.

Pesticide concentrations varied significantly along the watercourse due to the presence of different sources (groundwaters, wastewater effluent, tributary contributions, brackish waters, etc.) and physicochemical/biological processes that take place simultaneously. The most commonly detected analytes were propyzamide, triazine compounds and chlorpyrifos.

A clear seasonal pattern has been detected, with a predominance of insecticides during Summer and of herbicides during Winter. The input of pesticides through this watercourse is particularly relevant during periods of heavy rain, representing more than 70% of total yearly input for many of them.

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Improved Port Efficiency and Safety providing Enhanced Vessel Navigation

Container Vessel

Docking Assist will create a centralised, cost-effective, real-time, accurate vessel location and monitoring system, providing the necessary centimetre positioning/speed accuracy.

This system will provide efficient and safe manoeuvring within the entire navigation harbour zone enhancing vessel trajectory, and providing constant monitoring for moored/docked vessels.

The DockingAssist system is composed by two parts:

  • The harbour will be equipped with a differential GNSS Base Station, and a Wireless Technology offering a range of several kilometres, in order to send the DGPS corrections data to the vessels, and receive real-time position, speed and heading data from them.
  • A portable unit will be equipped on the ship side composed mainly of a DGPS receiver and a Wireless node to receive the indications from the harbour.

Main Benefits:

  • Time reduction in transit, enhancing port traffic management and throughput with minimum investment.
  • Reduction in operating expenses, CO2 emissions and fuel usage.
  • Less environmental impact of shipping.

For more information, please visit the official web site

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Sea slug’s ‘disposable penis’ surprises

Sea slug

Japanese researchers observed the bizarre mating behaviour in a species called Chromodoris reticulata, which is found in the Pacific Ocean.

They believe this is the first creature known that can repeatedly copulate with what they describe as a “disposable penis”.

The study is published in the Royal Society’s journal Biology Letters.

Almost all of these creatures, which are also known as nudibranchs, are thought to be “simultaneous hermaphrodites”. This means they have both male and female sexual organs and can use them both at the same time.

The Japanese team observed sea slugs that they had collected from shallow coral reefs around Japan. They saw the animals mate 31 times.

The act took between a few seconds and a few minutes, after which the creatures would push away and shed their penises, leaving them on the floor of the tank.

Sea slugs are not the only animals who abandon their penis. Orb weaving spiders are known to lose their male organs after sex, as does a sea creature called the periwinkle and land slugs belonging to the genus Ariolimax.

However the researchers believe that Chromodoris reticulata is the first creature known that can re-grow its appendage – and its disposable penis gives it a sexual advantage.

For more information, please visit the royal society web site

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