30.01.2014
The oceans are the biggest and as yet least explored biosphere on the earth. We have, however, succeeded in increasing our understanding of the marine ecosystem to a substantial extent in recent decades – and have been forced in this context to face the fact that we have made things excessively tough for the sea. The consequences of our actions are obvious. Callum Roberts, marine biologist and Professor of Marine Conservation at the University of York in England, puts it in a nutshell when he points out that the oceans have been overfished and are full of garbage and toxic substances [1]. The harmful effects of what we do are evident not just close to the surface but also deep below it. It is essential that something is done about this. Die-hard pessimists seem to think that it is pointless to fight for marine protection, however, in view of what they feel are the almost superhuman efforts that are needed to reverse the trend and in view of the enormous resources available to various interest groups that are primarily interested in economic exploitation of the marine ecosystem – in spite of the probable negative impact of this, about which environmental organisations issue constant warnings. Let us focus solely on the status quo, maintenance of which can already be considered a challenge. The ingredients on which the success of this depends are: immediate rethinking, considerable discipline and a tremendous amount of energy. We are told that it is time to accept responsibility – at the international level. This appeal is directed at global society, at all people, irrespective of their political views, cultural background or religious beliefs, at governments, the business community and industry. The feeling of powerlessness in the face of the size of the task has to be overcome, so that action is at long last taken. What is necessary here is a “Kaizen” process, i.e. changing (“Kai”) for the better (“Zen”). More exactly: everything is at stake! What is needed in the long term is therefore more than just goodwill. Today and in future, it is lateral thinkers, inventors and visionaries that are essential, who have imaginative ideas for effective innovations in such areas as energy generation and storage, raw material and food supply, waste prevention and recycling as well as use of air, land and water in a way that is both environmentally sound and economically viable. If they are taken decisively in the right direction, even small steps can lead to changes for the better. The "Blue Planet": The earth is covered with water to approximately 70 percent. (Source: NASA) Life depends on clean water Human beings need an intact environment to exist. It is essential and irreplaceable. Protecting and maintaining the earth in all its diversity also means drawing attention to the water that is vital to life and thus to the world’s oceans, the cradle of life, the reason why our “blue planet” is unique in the universe. It is up to us to avoid damage and to make sure that not only we human beings but also the flora and fauna survive. Although this is not an easy task, the problems will only become even more difficult to solve if we fail to tackle them resolutely now and hesitate to start taking sensible action that has long-term impact. All of us can probably remember watching a plastic bag blowing across the road. This scene alone says a great deal about how we see things as well as about the special features of polymer materials: they are lightweight but stable at the same time, they can be given individual designs and are versatile in their applications. Our world would not be the way it is without polymers. What is, however, often forgotten is that most plastics are extremely valuable energy sources, while they survive for hundreds of years – which is both a blessing and a curse. Those who are opposed to plastic use the word disparagingly, while plastic is a positive term to its supporters; while some chemists are fascinated by the polymer structure, others are interested in the petrochemical raw material from which plastics are primarily manufactured, well aware of the fact that their high energy content is a significant factor in electricity and heat generation. It is rarely the case, however, that plastics and polymers are recognised for what they really are: valuable materials that influence and enrich all aspects of our lives considerably. Thopuc of the Month: Plastics move the world Even though deposit systems in Germany and elsewhere have improved the image of polymer bottles, raising them to the same level as glass bottles and enabling them to be recycled in the same way, we are still far from reaching an ideal state in the way we handle plastics: most people would find it a strange idea to bend down and pick up a plastic bag in the way one would do so to pick up a coin. Literally “bowing down” before the polymer material like this would, however, be an effective way to initiate a global healing process in one small area. Plastic residue have collected in at least five places around the world’s oceans. (Source: U.S. National Oceanic and Atmospheric Administration) Plastics reach the world’s oceans primarily via waterways. It has not yet been determined conclusively what ultimately happens to them in the sea. No final answers have been found so far to many questions about, for example, the maritime transport channels and mechanisms; there are at best assumptions and initial investigations. In spite of this, what is certain is that the beaches of remote islands in isolated locations like Easter Island in the southeastern Pacific have also been affected by the synthetic waste our civilisation produces and are littered with our plastic debris. Experts do in addition agree that not inconsiderable amounts of plastic residue have collected in at least five places around the world’s oceans due to current flows and form areas that rotate around their own axis on a continental scale. At some time or other, plastic disintegrates into tiny fragments known as microplastic under the influence of salt, water and the sun. This microplastic does not, however, degrade to any further extent than this and certainly does not dissolve completely as is observed with organic material like wood. Microplastic spreads around the ocean; it ends up on beaches, where it mixes with the sand; it floats with plankton in the surface water of the sea, where its size, shape and colour mean that fish, mammals living in the ocean and seabirds confuse it with food and eat it. A varying number of plastic fragments is frequently found in dead seabirds; if a maximum of ten is counted, then the water is considered to be clean ... It is not known whether microplastic caused the animals’ death; it is difficult to settle this question at the experimental level. The background information behind the investigations made does, however, indicate a dangerously dynamic development that should give us all food for thought: one of the characteristics of plastic is that it removes – extracts, the experts say – and accumulate pesticides, heavy metals and other environmental poisons from water. Animals that eat microplastic ingest these toxins as well, so that they accumulate in their tissue. At the end of the food chain, the animals end up as seafood on our plates. It is only a question of time until unforeseen developments climb the evolutionary ladder and reach us. Marine pollution cannot be attributed solely to microplastic that is due to the disintegration of plastic residue. Some pollution is the direct result of waste water flows. Studies completed in Japan, for example, have revealed that plastic pellets which are an important additive in the raw materials used in plastic processing or in consumer and/or personal products (e.g. toothpaste) contribute to marine pollution too. Although the sources of contamination may well be different, the impact on the marine environment and the creatures that live in it remains fundamentally the same. The inhabitants of Easter Island cleared their entire island of trees in order to build statues for their gods and then died of starvation when the soil dried out. (Source: istockphoto) Don’t look the other way It can be concluded from what has been outlined so far that the prospects for our environment and thus for us as its inhabitants may not be encouraging, but they are not hopeless. It would be completely wrong simply to look the other way and to let things run their course in an – ultimately irresponsible! – fatalistic belief that a catastrophe is inevitable. The opposite is the case: appropriate, intelligent action needs to be taken now. The marine biologist Callum Roberts reports that there are enough examples in history which demonstrate how civilisations were destroyed by environmental catastrophes that they unknowingly brought on themselves: “The inhabitants of Easter Island cleared their entire island of trees in order to build statues for their gods and then died of starvation when the soil dried out. The people of Mesopotamia developed an agricultural system with ingenious irrigation procedures, but in the end this method meant that the fields contained so much salt that no crops grew on them any more. The process adopted by the Maya to farm mountain slopes involved the removal of all the topsoil in the entire region, so that a long drought led to the collapse of this unusual culture.” [1, P. 14] In just five years, predicted Boyan Slat, could be estimated fishing around seven million tons of plastic out of the sea. (Source: Boyan Slat) We are not blind; we can see perfectly clearly. Even if we have the impression that we are shutting the stable door after the horse has bolted, this is not the case by a long way. A longing for change has always proved to be a strong driving force throughout the history of humankind. Some research scientists are convinced that at least the plastic in the world’s oceans could be removed in only a short time. One of these idealists is the 20-year-old Dutchman Boyan Slat. This aerospace engineering student has ideas, visions and a sense of mission. He predicts that an estimated roughly seven million tonnes of plastic debris – the equivalent of the weight of 1,000 Eiffel Towers – could be fished out of the sea in only five years. How is this supposed to be possible? According to the budding engineer, with the help of enormous filteringsystems anchored to the ocean floor and floating on the surface of the water, that catch all plastics via arms attached to their sides and fish them out of the water. The system operates passively, using only ocean currents, which wash the plastic particles in the direction of the filtering platform, where they are extracted and collected. Plankton that is important for the creatures living in the ocean would be washed out, while the plastic could be recycled in a profitable business operation (including rare earths, the natural reserves of which have been exhausted almost completely and which supposedly adhere in large quantities to the plastics afloat in the sea. Would it be possible to put Boyan Slat’s idea into practice? Some people may well consider the young, up-and-coming scientist to be naive. But isn’t that what we need at the present time, people who are willing to think outside the box and to fight for what appear to be crazy ideas too? One can only hope so: according to an estimate compiled by the United Nations, about 6.5 million tonnes of new debris reach the oceans every year. Das "Ocean- clean-up"-Projekt von Boyan Slat. Tray Mincer and colleagues found cells that chew floating micro-plastic in the sea. (Source: Woods Hole Oceanographic Institution in Woods Hole, Massachusetts/USA) Mother Nature finds a way While just a few people are racking their brains to try and find a way to reduce marine pollution by microplastic, Mother Nature has evidently developed a concept of her own to deal with the problem. Tracy Mincer from the Woods Hole Oceanographic Institution in Woods Hole, Massachusetts/USA, came to this conclusion recently. The marine biologist and his team of scientists discovered in electromicroscopic examinations of plastic debris from the Sargasso Sea, part of the Atlantic Ocean east of Florida, that bacteria-like cells settle in small notches on the surface of plastics. Tracy Mincer and his colleagues report that it seems as if the cells they monitored in the “plastisphere” were literally eating away the plastic [2]. Microbes that digested plastics had apparently already been found on landfill sites; now they had for the first time discovered bacteria in the sea that evidently have similar capabilities. Tracy Mincer and his colleagues are still only in the initial stages of their investigation at the present time, although a decision has been taken to continue it. The objective is to grow cultures of the cells that devoured plastic residue in the ocean – without harming the marine environment. If Mincer’s research approach proves to be correct and the results are promising, this would be major progress towards clean oceans. We should not rely on this being the case, however. It might perhaps even be sensible to assume the opposite. Then there would be a good chance of initiating a process of rethinking, at the end of which we at long last see plastics as being more significant and valuable – so that we then no longer throw them away unthinkingly in the environment. Because this is the main problem. Guido Deußing Literatur: [1] Callum Roberts: Der Mensch und das Meer. Warum der größte Lebensraum der Erde in Gefahr ist. Munich: Deutsche Verlags-Anstalt 2013 [2] Erik R. Zettler, Tracy J. Mincer, Linda Amaral-Zettler: Life in the “Plastisphere”: Microbial Communities on Plastic Marine Debris. Environ. Sci. Technol., 2013, 47 (13), pp. 7137-7146 Further information: Greater sustainability and protction of freshwater lakes (01/2013) Plastics bags on trial (TdM 10/2011)
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