Boats and ecology

2000/11/07 Roa Zubia, Guillermo - Elhuyar Zientzia

• Garraioak
• Ingurumena

The sea says nothing aloud. It seems that this large mass of water has the ability to remove all problems. Sea problems are more difficult to analyze than ecological disasters on land. However, sometimes the consequences are very evident in the vicinity of the coasts and that is when the distresses occur.

The human footprint in the sea is wide. The most striking problems are the problems of the loads that drag or bring ships. Unfortunately we have considered frequent oil spills, but we cannot forget those produced in other cases.

Platform problems

In the last decade, for example, the history of the eccentric Brent Spar platform has been at its peak. The use of the platform was considerably reduced and it was decided to sink. It did not seem like a very ecological action for containing heavy metals in the cavities. A major Greenpeace campaign ended without sinking. Subsequently, scientists have discovered that certain metals poisonous to humans are essential for the biomass of the seabed. After all, what we learned from this fact was that we know little about the ecology of the sea. Although pleasant surprises occasionally arise, new studies pose many other problems.

All ships, both small and large, pour fuel remains in their normal activity. Like cars. In this sense, a year ago the journal Nature published the results of a curious satellite research. What happens is that from space you can see the usual routes of commercial ships, where many clouds are generated. The origin of these clouds was sulfur dioxide from the transformation of molecules from phytoplankton. But phytoplankton is not the main source of this compound. By satellite it can be observed that the quantity emitted by the ships is much greater than that which comes from the sea. This effect is very remarkable in the northern hemisphere, where the largest number of ships are concentrated.

If explored in shipbuilding there are other types of chemical supports. In this activity wood and metal have been discarded. As in other technologies, polymers have been a real revolution. In fact, the mixture of polyester and fiberglass is considered a classic material in the shipyards. However, a resin containing large amounts of styrene is often used to protect these structures. Styrene is the main substance that has led to the Ievoli Sun accident. European regulations are very demanding with authorized styrene concentrations. Therefore, several European shipping companies and experts from other industries have come together to conduct new research. It proposes the use of other material for the realization of basic structures. The use of polypropylene in the polyesters' place prevents the addition of resins through thermoplastic procedures. The research of these new materials promoted in Europe is very representative for the debate on styrene risk.

The latest issue of the journal Nature has also published the results of another study related to the influence of ships. This is a work done at an environmental research center in Maryland. This is a study of another type of pollution that is mentioned very rarely and is not about pollution. In fact, the authors of the article have discovered that viruses and bacteria are transported from one territory to another by boat. The stability of oil tankers on empty trips is very low. In open sea this situation can be very dangerous and therefore flood the tanks. Ballast is usually water. At the spring of origin, when the water is taken from the sea and the journey ends, it is released. However, it should be noted that sea water is not only water, but a type of "biological broth" full of microorganisms. Therefore, microorganisms are transported and released from one end of the world to another. "Microorganisms present in ballast water frequently invade coastal ecosystems," US scientists say, as these microorganisms are released in large concentrations and are foreign to released ecosystems. Both characteristics greatly facilitate biological contamination.