Different factors have a negative impact on the ocean flora and fauna. One of the problems that do significant harm to the marine creatures is the oil spills that are regarded as a form of pollution. It is a well-known fact that oil is very important for present day-society as it enables functioning of many industrial objects. Oil is a source of the petrol for almost all vehicles that are being used by people nowadays. Oil is frequently used in pharmacology as well. It is hard to mention all positive features that oil has, but due to them. this chemical substance is often called “black gold”. The one who has oil has a real treasure.
Nevertheless, in the pursuit of wealth, oil producers and buyers often neglect the important rules of oil production and transportation. This carelessness often results in a real disaster to the nature of oceans and their coasts, as oil is usually taken from the ocean floor from the mineral scattering halo and is often transported by tankers across the ocean. Neglecting of basic transportation and production rules leads to oil spill, which is extremely dangerous for various marine creatures that include animals, plants and microorganisms. As it is necessary to be aware of the causes and outcomes of this problem, the paper addresses the issue of oil spill in ocean, analyzes the reasons of spillage, the way oil is spread and the effects of this process on the nature.
The Causes of Oil Spills
There can be different reasons for oil spillage in the ocean. Usually oil spills appear due to accidents with barges, tankers, refineries, pipelines and storage environment involved. According to the Office of Response and Restoration (2014), spills occur due to such factors:
- Carelessness of oil producers or transporters or mistakes they make;
- The mechanical breakdown (equipment failure);
- Natural causes (disasters: hurricanes, tsunamis, typhoons, etc.);
- Deliberate actions of those people that want the spill to happen and cause both environmental and financial problems (terrorists, vandals, countries at war, illegal oil dumpers).
The first cause is the clearest one and occurs rather often. Oil manufacturers aim at producing as much oil as they can in the shortest time possible. For this reason, they often neglect various recommendations and do not care about environmental aspect of the issue. Some loss of this chemical substance does not cost as much as the idle time. Environment protection is not their concern.
Mistakes can occur due to the lack of experience of those people who work at oil mining stations. Sometimes workers are just unaware of what to do in some cases, especially when the pace of production deviates from the suggested variant. Another matter of human factor mistakes is the change of the equipment and insufficient training of the personnel and lack of practical aid in the case of mechanism replacement. When the machines that are used to produce oil are changed to new or just different ones and workers do not have enough awareness of them, it is very probable that they unintentionally can make some mistakes that may result in oil spillage. Human factor can also include harmful activity both on land and in the sea. It usually occurs when oil products are washed off into the water from the coast.
The mechanical breakdown (equipment failure) is usually connected to the damages of the oil mining equipment or the vehicles that transport oil or oil products from the sea to the land or from one country to another one by sea. It is apparent that oil mining equipment can break down just like any other mechanism. The most frequently discussed issue is oil spill that occurs during transportation. Oil is usually transported by tankers, and when they are physically damaged (literally: have holes through which oil can flow out) the chemical substance that is used to produce petrol runs out. Mechanical damages usually occur when the tanker is stuck in the shallow and tries to get out of it or if the tanker comes through the places with a lot of reefs and is damaged by them.
Natural disasters such as hurricanes, tsunamis, typhoons and storms can provoke oil spillage as well. When tankers are out in the sea and get caught by storm, they can be shipwrecked. The equipment used to produce oil at sea side can be also damaged due to tsunami or typhoon and, therefore, the spill to the ocean occurs.
Sometimes, oil is spilled to the ocean due to deliberate actions of some people. Usually the mining equipment or tankers are damaged by the terrorists or the owners’ competitors that are aimed at causing financial losses to the company that produces oil. If one country wages war against another one, its rival can intentionally damage tankers and production machines to cause additional problems to another country. Vandals destroy the vehicles or equipment with no deliberate reason. Illegal oil dumpers usually use bad or old equipment and, trying to produce oil fast, they do not follow the rules of production technology and drilling in the sea. Therefore, the spill occurs.
The Things that Happen to Oil in the Water
Different weathering processes have some effect on the spread of oil and its behavior at sea. Some of them, such as dispersion (spread of oil), evaporation, sedimentation (settling of oil at the bottom of the ocean or sea and formation of the solid layer) and dissolution (changing and disappearing) make oil vanish from sea surface (ITOPF, 2013). Some other processes improve the persistence of oil on the surface. Such processes include “the formation of water-in-oil emulsions” (“mousse”) and the growing viscosity of oil (ITOPF, 2013). All these weathering processes, along with quantity of oil spilled, its type and the remaining on the surface of the water or washing to the shore define the speed of oil spread and the consequences on the nature it has. The most important thing is that spilled oil is assimilated by the marine environment. The process of such an assimilation is called biodegradation. International Tanker Owners Pollution Federation (2013) provides a diagram that enables understanding of the processes that happen to spilled oil.
Right after the oil is spilled, it begins to spread over the surface of the sea. First, this chemical substance spreads as a single slick, but a few hours later the spot breaks into smaller ones since the wind and waves affect the spillage (ITOPF, 2013). The speed of oil spread depends also on the thickness and viscosity of oil. If it is more fluid and has low thickness and viscosity, it spreads faster. On the contrary, oil with high thickness and viscosity spreads slower and does not break into separate spots as fast as with lower indicators. The direction of spread is determined by the wind. The speed of oil spread is also influenced by the wind speed, temperature, water currents and tides (ITOPF, 2013).
The Effects of Oil Spills on Ocean Nature
Oil spills have a negative effect on the marine and coastal flora and fauna. Scientists claim that after the explosion BP's Deepwater Horizon oil rig, around 170 million gallons of oil ran out to the Gulf (National Wildlife Federation, n.d.). The results of the explosion are shocking: more that 8,000 marine animals, birds and sea turtles are estimated to be injured or dead in a six months period after the accident took place.
According to Ports & Maritime Organization (2013), oil spill pollution can have long-term and short-term effects. First group includes suffocation and oil poisoning. Because of its thickness and viscosity, oil remains on the water surface. Therefore, it prevents light from penetrating into water and marine plants along with phytoplankton cannot have photosynthesis. As the surface is covered with oil, water cannot absorb enough oxygen and many sea creatures die because of insufficient oxygen dissolution, which is smaller than in the deeper ocean levels. Insufficient quantity of oxygen prevents marine plants and phytoplankton from photosynthesis as well as absence of light (Ports & Maritime Organization, 2013).
Oil spillages have negative influence on sea birds as well as on plants and phytoplankton. When oil penetrated to the birds plumage, they become more vulnerable to the changes in the temperature as their insulating ability decreases. As birds are covered with oil, they cannot swim without difficulties because due to its viscosity, oil constrains their movements. For the same reason, birds also lose their ability to fly, so they die because of hunger or being caught by predators (Ports & Maritime Organization, 2013).
As the process of sedimentation takes place after oil is spilled, the ecosystem on the bottom of the ocean floor suffers too. Since oil is rather toxic, coastal plants, and algae in particular, are eradicated. Animals, including birds, can die of poisoning, if they appear in oil slick of high concentration. Worms and microorganisms can be poisoned as well. The younger these organisms are, the more vulnerable to oil they become. Ports & Maritime Organization (2013) also reports that humans and animals that live near the area where spillage occurs are threatened too. Oil contains different microelements such as benzene, toluene and xylene that negatively affect people. Such aromatic hydrocarbons as Naphthalene and Phenanthrene are very dangerous for fish (Ports & Maritime Organization, 2013). Since these aromatic compounds are soluble, they poison sea creatures and penetrate into the surface and groundwater, poisoning organisms that do not have direct contact with oil. The effect of these microelements can become not that serious with time because they are volatile (Ports & Maritime Organization, 2013).
Ports & Maritime Organization (2013) reports that there are researches that prove the fact that microelements found in oil have some impact on the reproduction, growth and behavior of animals. Eggs and larvae are affected the most. Fish become less sensitive to various diseases. Phytoplankton does not grow, so other sea creatures that eat it do not have enough food. Many sea mammals that are covered with fur die due to the same reason as birds as they lose their ability to become adjusted to the temperature, do not have a possibility to swim and get food. Around 70 years are needed for marine nature to revive after the oil spillage (Ports & Maritime Organization, 2013).
All in all, oil spills to ocean is an extremely serious problem that has a severely affects the environment. For this reason, it is vitally important to prevent accidents at sea to preserve the life of marine creatures. There are different causes of oil spillages; the most frequent one is the damage of oil mining equipment and tankers and barges used for transportation. Many animals, plants and microorganisms die because of suffocation, poisoning and starvation caused by oil spill. Therefore, this issue should be controlled by the producers and transporters of oil, manufacturers of mining equipment and transportation vehicles, governments and different environmental organizations to protect both people and sea nature.