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Covering nearly three-quarters of the Earth, the ocean is an extraordinary resource. We depend on our ocean for the food we eat, the water we drink and the air we breathe. The ocean sustains nearly half of the global primary production and it is home for a multitude of marine organisms. It supports fishing industries and coastal economies, as well as providing recreational opportunities. Land and sea, no matter where we are, are connected. For too long, we have used the ocean as a receptacle for our trash; marine litter has become one of the most pervasive pollution problems facing the world’s oceans.
Marine litter is any persistent, solid material that is manufacturer or processed, and that is directly or indirectly, intentionally or unintentionally discarded, disposed or abandoned in marine and coastal environments. Marine litter includes objects that typically do not naturally occur in the marine environment. The most common materials are: plastic, glass, paper, metal, rubber wood and cloth. These materials can enter the environment in two ways: directly through human action or indirectly when blown or washed out to sea via rivers, streams, and storm drains.
Once marine litter enters into the ocean, how long it will remain depends upon the material by which they are made of: plastic and synthetic rubber are the most persistent between marine debris.
Over 80 % of marine debris is plastic.
Look around you. Everywhere we look we will find plastic: in the clothes we wear, in the houses we live in, in our cars, bicycles, planes and trains we travel with. We use plastic for cleaning ourselves, we use plastic for packaging our food, we use plastic for fun in our toys and games, we use plastic in almost every single aspect of our life. Plastic is made of a wide variety of artificial chemical compounds and it can be manufactured in many different shapes, sizes and colours. Plastics are inexpensive, lightweight, strong, durable, corrosion resistant and have with high thermal and electrical insulation properties.
World plastics production has kept growing for more than half a century, rising from approximately 1.9 tons in 1950 to 300 million tons in 2013. In Europe alone, the plastics industry has a turnover in excess of 300 million euros and employs 1.6 million people.
Even though some plastic waste is recycled, up to 10 % of plastics produced is estimated to end up in the oceans.
Researchers estimates that out of a total of 192 countries with coastlines, just 20 countries are responsible for 83% of the plastic debris put into the world’s oceans. These 192 countries produce some 275 million metric tons of plastic waste each year. Of that volume, about 5–13 million metric tons of mismanaged plastic waste is thought to have entered the ocean in 2010. Without improvements to waste management infrastructure, this volume of plastic debris could more than double by 2025.
Plastic enter the oceans from land based sources, when items that are not thrown away correctly, or when they are blown or washed into waterways from landfills and recycling plants. Plastic can also enter the environment from ocean based sources including fishing and cargo vessels, as well as recreational boaters and oil and gas drilling platforms.
Irrespective of how plastics enter the marine environment, they never, truly disappear.
Over time, it will break down to small, microscopic pieces and persist in the environment: plastic never truly goes away, it just becomes smaller and smaller…
Plastics in fact do not biodegrade. Instead, it breakdown into small pieces due to oxidation or to the physical action of waves, currents, and the grazing activities of fish and birds. Plastic can also break down when exposed to sunlight, a process called photodegradation. Unlike natural material that will break down and be utilised by living organisms, plastic never truly goes away, it just becomes smaller and smaller and smaller….When it breaks into pieces smaller than 5 or 1 mm in diameter, it is known as microplastics.
Microplastics are the most abundant type of plastic in the ocean, and they have been found in every corner of the ocean sampled by scientists to date, from near-shore environments to the open ocean, including remote pacific islands and the Arctic.
Most small microplastics fragments results from the breakdown of larger plastic items but the breakdown of larger pieces of plastic is not the only way in which microplastics end up in the ocean. The plastic pellets used as a feedstock for producing plastic goods can spill from ships or land-based sources, and “microbeads” used as scrubbing agents in personal care products such as skin cleansers, toothpastes, and shampoos, can escape through water treatment facilities and pass into watersheds with treated water. Eventually, once in the marine environment, microplastic can be transported between all compartments of the water column from surface waters to deep sea sediment. High concentrations accumulate in convergence zones and along exposed coastlines, and in areas with limited water circulation or those surrounded by densely populated urban areas.
Recent scientific researches estimate that 5.25 trillion of plastic pieces, the majority microplastics, are floating in the world’s oceans and meet with phyto and zooplankton, crustaceans, molluscs, fish, turtles, seabirds and marine mammals every single day.
Scientists have found that plastic affects at least 267 species worldwide, including 86% of all sea turtle species, 44% of all seabird species, and 43% of all marine mammal species. It is quite scary to think that this numbers may be highly underestimated as most victims are likely to go undiscovered by scientists, as many sink or are eaten by predators.
Plastics harms wildlife in both a direct and indirect ways. The direct effects of plastic include plastic ingestion and entanglement.
Entanglement in plastic debris, especially in discarded fishing gear, is a very serious threat to marine animals. It can cause wounds that can lead to infections or loss of limbs; can impair an animal’s ability to swim, which may lead to drowning, or make it difficult for the animal to move, find food, and escape from predators, or can cause strangulation, choking, or suffocation. More than 100,000 marine mammals die every year from entanglement or ingestion of marine debris.
Fishing nets, fishing line, ropes, plastic sheeting and packing straps can be a major problems for animals that interact with fisheries, such as dolphins. Fish and crustaceans are frequently entangled in lost or discarded fishing items, a phenomenon known as ghost fishing. Thousands of seabirds are thought to die from entanglement or ingestion each year. When birds prey upon entangled fish, they can become entangled themselves.
Wildlife eat plastics. Some have the ability to remove it from their mouths, but ingestion occurs when an animal swallows the plastic item. Ingestion can be accidental, but animals may ingest debris because it actually looks like food.
Once ingested, plastic can cause the blockage of the secretion of gastric enzyme, can diminish the feeding stimulus, can lower the levels of steroid hormone or even delay ovulation and cause reproductive failure.
Many types of birds have been found to feed on plastic pieces, most likely because they mistake them for food. Plastic eaten by adult birds can be regurgitated as food for hatchlings, potentially generating a population problem, especially when the offspring are never fed real food. Also loggerhead sea turtles have been found to feed on plastic and at least 26 species of cetaceans have been documented to ingest plastic debris. A number of benthic invertebrates including lugworms, amphipods and blue mussels can feed directly on microplastics. Microplastics are ingested by commercially important invertebrate species, including crustaceans and bivalves. Also microplastic ingestion by wild caught fish species is not an uncommon observation. For example, commercially caught fish and mesopelagic fish from the English Channel and the North Pacific had microplastics in their digestive tracts.
The indirect effects of plastic may include chemical leaking. Plastic debris contains chemicals that are added to the polymers in the production phase in order to give to the material the required characteristics of colour, texture and flexibility. But they also absorb environmental contaminants from the water. Plastic acts in fact as a sort of sponge, accumulating pollutants such as PCBs from seawater. These chemicals could have negative effects on animals that ingest contaminated plastics.
Another indirect effect of plastic pollution is the introduction of alien species. Plastics floating at sea may be colonised by various encrusting organisms such as bacteria, diatoms, algae, barnacles, hydroids and tunicates. Drift plastics can introduce species into an environment where they were previously absent. The arrival of unwanted and aggressive alien species could be detrimental to littoral and shoreline ecosystems.
Land and sea, no matter where we are, are connected.
Any trash that is disposed of improperly can potentially enter the ocean or other waterways, and anyone who disposes of trash improperly can be a source of marine debris! Yes, even you!
Marine debris is one of the greatest threats our ocean faces, but luckily it is an issue with which we can all play a part in the solution.
We all should be aware that plastics and plastic chemicals are ubiquitous, and we truly can’t eliminate all risks associated with plastics. But we can reduce them, and we can chose to support businesses and institutions that are attempting to do the same.
Plastic pollution can be reduced by using less plastics products and switching to alternatives.
Among the existing solutions recycling is one of the most convenient and easiest ways. As consumers, the recycling only requires one easy step of putting plastic wastes in right bins for disposal.
To be effective our actions should embrace the so called five R’s: ‘reduce, reuse, recycle, recover and redesign’.
There are some very simple actions which everyone of us can take to reduce our plastic footprint:
- Try to avoid using or buying items that used an unnecessary amount of plastic.
- Avoid plastic bottled water (carry around with you your own flask, fill it when you are thirsty)
- At home, drink tap water. If you do not like the taste, add a few slice of fruit or filter the water thanks to in-expensive filter jugs. Tap water is better than bottled water because it isn’t stored in plastic and has much higher regulation standards
- Don’t buy beverages bottles made of plastic
- Bring your own cloth bags when shopping. Remember that between 500 billion and a trillion plastic bags are consumed worldwide each year. Less than 1% of bags are recycled. Plastic bags are used for an average of 12 minutes, but a single plastic bag has a life expectancy of up to 1,000 years!!!
- Cosmetic choice: avoid all scrubbing products containing plastic. Did you know that the best scrub ever is done with inexpensive and completely biodegradable products, such as honey and brown sugar? Give it a try!
- Carry your own reusable steel or ceramic beverage container.
- Store all your food in glass containers instead of plastic containers.
- Don’t buy convenience foods packages in plastic, avoid fruit wrapped in plastic and prefer fresh eggs in reusable paper containers.
- Prefer natural fabrics
- Say no to plastic straws. You can buy stainless steel and glass straws to carry with you
- Do not release balloons: you may have fun, but the animal that is ultimately going to encounter it won’t be of the same opinion!
- Recycle your six-pack holders wherever is possible. If you can’t recycle, you can always cut or tear the rings to prevent marine animals entanglement.
- Smokers: Use matches instead of plastic encased lighters and use portable ashtray to prevent the loss of plastic filters (cigarette butts) into the environment
WHAT EACH AND EVERY ONE OF US DOES IN OUR DAILY LIFE WILL MAKE THE DIFFERENCE. TAKE RESPONSIBILITY FOR YOUR OWN WASTE: SPREAD THE VOICE!!
Currently, we are living in the geological epoch of Holocene. The Holocene started 12,000 years ago, at the end of the last Ice Age, and it was characterised by a period of stable climate during which all human civilisation developed. However, since the mid-20th century, the Earth has witness a dramatic acceleration of carbon dioxide emissions and of sea level rise, a global mass extinction of species, and an extensive land transformation induced by human activities. These human induced changes could mark the end of that slice of stable climate known as Holocene, and give way to the ‘Anthropocene’.
The ‘Anthropocene’ is a term coined in 2000 by the Nobel Prize-winning chemist Paul Crutzen, together with Eugene F. Stoermer, to denote the present time interval, in which many geologically significant conditions and processes are profoundly altered by human activities. Since then, the term has been widely used (and discussed) by many Earth/ environmental scientists.
Why ‘Anthropocene’? The rationale behind this name is the recognition of the wide-ranging effects that humankind presence and activities are having on the Earth. These human-induced effects include changes in every aspect of the planet, from the atmosphere (air) to the geosphere (soil), passing through the biosphere (living organisms) and to the oceans and waterbodies.
In particular, these human-induced effects include changes in:
- erosion and sediment transportation, which are associated to a variety of anthropogenic processes, including colonisation, agriculture and urbanisation;
- the chemical composition of both atmosphere, oceans and soils. For example, the level of CO2 in the atmosphere has now reached 400 part per million, while it was at 280 ppm just before the industrial revolution. And it is still, currently, rising. In the soils, both nitrogen and phosphorous levels have doubled during the past century due to fertiliser use. This is likely to be the largest impact on the nitrogen cycle in 2.5 billion years. These significant anthropogenic perturbations of the cycles of elements generate associated environmental conditions. Just to quote the most well-known: global warming and ocean acidification.
- the biosphere both on land and in the oceans. Humans have triggered a wave of extinction, threat, and local population declines that is comparable in both rate and magnitude with the five previous mass extinctions of Earth’s history. The effects of this “sixth extinction wave” means that we are likely losing ~11,000 to 58,000 living species every single year (out of estimated total of 5 to 9 million species). And note that this is a conservative count. Across vertebrates, 16 to 33% of all species are estimated to be globally threatened or endangered. Among these, the most threatened are amphibians (41% of all species are globally threatened or endangered), followed by birds (17%), with mammals and reptiles experiencing intermediate threat levels. Loss of invertebrate biodiversity has received much less attention, and data are extremely limited. However, of the species assessed, ~40% are considered threatened. If current trends continue, the Earth is on course to see 75% of species become extinct as a result of habitat loss, predation, species invasions and the physical and chemical changes noted above.
The evidence of the mankind impacts on the planet Earth are truly overwhelming, but these changes are very recent in geological terms. In the Geological Time Scale, an epoch usually spans tens of millions of years, while the ‘Anthropocene’ might have started just around the 1950 (the starting date of the ‘Anthropocene’ is currently widely debated). Furthermore, stratigraphic scientists consider the Geological Time Scale as the very backbone of geology and changes to it are not amended lightly. Today, in fact, the ‘Anthropocene’ is not a formally defined geological unit within the Geological Time Scale. Not yet, at least.
In 2008 an assessment by the Stratigraphy Commission of the Geological Society of London made a case for formally incorporating the term into the Geological Time Scale. Recently, an official expert group called ‘the Anthropocene Working Group” (WGA), which activity started in 2009, has reunited at the prestigious International Geological Congress (held in Cape Town at the end of August 2016) to examine the status, hierarchical level and definition of the ‘Anthropocene’ as a potential new formal division of the Geological Time Scale. Following the discussion, WGA members will spend the next years determining which signals and location show the strongest and sharpest evidence of the start of the Anthropocene, to then make a formal recommendation to declare the ‘Anthropocene’ to the International Commission on Stratigraphy.
Changing the very backbone of geology to include the ‘Anthropocene’ within the Geological Time Scale would be a truly historic decision, which would clearly recognize the responsibility of the human kind in changing the planet Earth atmosphere, geosphere and biosphere.
A number of different starting dates for the ‘Anthropocene’ have been proposed, reflecting different disciplinary approaches and criteria regarding when human societies first began to play a significant role in shaping the Earth’s ecosystems. Two pre-industrial events have occasionally been proposed as markers of the ‘Anthropocene’ beginning; the wave of extinctions of the Pleistocene megafauna and the advent of agriculture (the so-called Neolithic Revolution). Some others proposed the advent of the Industrial Revolution (occurred around 1800) as the a logical start date for the ‘Anthropocene’. Even if it’s probably around this date that human impacts on the Earth’s atmosphere and geosphere became substantial, it’s actually around the 1950 that the human-induced changes have reached what some scientists called the “Great Acceleration”. The “Great Acceleration” has been identified by taking in consideration several different indicators of the development of human enterprise, from the beginning of the Industrial Revolution to the beginning of the new millennium. Such indicators included, between others: human population, damming of rivers, fertilizer consumption, water use, the concentration of atmospheric carbon dioxide and methane, ozone depletion, Northern Hemisphere surface temperature and the loss of global biodiversity. Each and every of these indicators underwent a sharp increase in rate around 1950. For example, the atmospheric carbon dioxide concentration grew from 311ppm in 1950 to 369ppm in 2000. From the perspective of the “Great Acceleration”, the mid-90s appear as good candidate to mark the start of the ‘Anthropocene’.
It has to be considered that a stratigraphic evidence is needed in order to formally define a geological epoch in the Geological Time Scale. In this sense, the WGA suggests the 1945 as the GSSA (Global Standard Stratigraphic Age) for the ‘Anthropocene’. On 16 July 1945, the first nuclear bomb was detonated by the United States Army at Alamogordo, New Mexico. The radioactive elements from nuclear bomb tests blowed into the stratosphere before settling down and being deposited to Earth. However, there would be so many other signals. Other candidates include aluminium and concrete particles, and high levels of nitrogen and phosphate in soils, derived from artificial fertilisers.
Another candidate would be plastic pollution. Humans are putting so much plastic in our waterways and oceans that microplastic particles are now almost virtually ubiquitous, and plastics will likely leave identifiable fossil records for future generations to discover.
About biological signs, the domestic chicken is a serious contender to be a fossil that defines the ‘Anthropocene’ for future geologists. The domestic chicken is a much bigger bird and with a different skeleton than its pre-war ancestor. Since the mid-20th century, it has become the world’s most common bird, being fossilised in thousands of landfill sites and on street corners around the world. The debate around the starting date and the signals that define the beginning of the ‘Anthropocene’ is still ongoing.
On the other hand, some scientists argue that the drive to officially recognize the ‘Anthropocene’ is political rather than scientific. These authors point out that, in contrast to all other units of the Geological Time Scale, the concept of the Anthropocene did not derive from the stratigraphic record. The concept of the ‘Anthropocene’ was formulated first, and stratigraphic evidences are searched as a consequence of this formulation. Furthermore, the ‘Anthropocene’ stratigraphic record is negligible, especially with a boundary set at 1945. Finally, these authors highlight that most of the stratigraphic records mentioned are potential records that might appear in the future.
Others claims that sufficient evidence has emerged of stratigraphically significant changes (both elapsed and imminent) for recognition of the ‘Anthropocene’ . The base of the ‘Anthropocene’ may be defined by a GSSP in sediments or ice core, such as the appearance of manufactured materials in sediments, including aluminium, plastics, and concrete, coinciding with global spikes in fallout radionuclides and particulates from fossil fuel combustion.
So, is the drive to officially recognize the ‘Anthropocene’ political or scientific?
It has to be noted that even in the very first paper in which the term ‘Anthropocene’ was used, the authors themselves declare that he ‘Anthropocene’ epoch initiative as primarily intended to draw attention to the serious ongoing challenge that faces mankind:
“To develop a worldwide accepted strategy leading to sustainability of ecosystems against human induced stresses will be one of the great future tasks of mankind, requiring intensive research efforts and wise application of the knowledge thus acquired in the noösphere, better known as knowledge or information society. An exciting, but also difficult and daunting task lies ahead of the global research and engineering community to guide mankind towards global, sustainable, environmental management” Crutzen & Stoermer, 2000.
Also the reception of the concept of ‘Anthropocene’ had shown a political interpretation:
“Official recognition of the concept would invite cross-disciplinary science. And it would encourage a mindset that will be important not only to fully understand the transformation now occurring but to take action to control it. … Humans may yet ensure that these early years of the Anthropocene are a geological glitch and not just a prelude to a far more severe disruption. But the first step is to recognize, as the term Anthropocene invites us to do, that we are in the driver’s seat. (Nature, 2011, p. 254)”
The debate around the ‘Anthropocene’ formalization is ongoing, scientists are currently researching around this topic to define if the ‘Anthropocene’ can be officially defined as a geological era with scientifically acceptable criteria. A political drive is probably not completely avoidable around this topic, as the concept of the ‘Anthropocene’ has the capacity to become the most politicized unit, by far, of the Geological Time Scales.
While it will be science to tell if we can truly consider the ‘Anthropocene’ as a geological era, the power of this concept shouldn’t be underestimated. The Anthropocene represents a new phase in the history of both humankind and of the Earth, when natural forces and human forces became intertwined, so that the fate of one determines the fate of the other.
If even just the debate around this topic can be used to create awareness around these important environmental issues, or as an encouragement to slow carbon emissions and biodiversity loss, or as an evidence in legislation on conservation measures, well, this is a debate that by all means, as humankind, we have the responsibility and the duty to face.