363220-123825Subject: English<br />Teacher: Zita Roberto<br />64008080010<br />Ana Almeida <br />Inês Alves <br />Magda Ismail <br />Teresa Santos11ºA <br />Index<br />Introduction……………………………………… Page 3<br />Sea Pollution: Direct and Indirect…… Page 4<br />Sea Exploration …………………………….… Page 5<br />So, what can I do to help? …………….. Page 6<br />Conclusion ………………………………………. Page 7<br />Bibliography ……………………………………. Page 8<br />
The existence of water in the liquid form is one of the reasons that makes our planet the perfect home for life.<br />From this fact, we can easily understand how important this substance is our existence. All forms of life totally depend on water to exist. Besides being the most important component of every living being, it helps regulating our body temperature and it is essential so that some crucial chemical reactions may occur.<br />Approximately 71% of earth’s surface is covered by water (oceans, rivers and lakes), which provides an habitat for a huge quantity of species.<br />The oceans also have a major role on the earth’s balance: <br />
The ocean tides contribute for the correct distribution of heat on the planet, and they are responsible for the oxygenation of still waters
The surface waters evaporation also represents an important part of the water cycle, causing the formation of clouds and, consequently, of rainwater
There is no doubt, though, that the modern human lifestyle has provided more and more individual comfort, over the years, since the industrial revolution. Unfortunately, in order to have this kind of living standard, we continually abuse of the earth’s resources and pollute its ecosystems.<br />Due to its importance, we are going to talk about sea exploration and sea pollution.<br />
One of the major pollution problems that nations of whole world have to face with is ocean pollution. The oceans of the world are becoming more and more polluted and some of the marine lives have been listed as endangered species. When an ocean is polluted, the marine life is directly affected and this indirectly affects human beings.<br />Indirect Pollution<br />It concerns the pollution that is not sent directly into the sea, but eventually gets there, vey often by natural run-off from the land.<br /> It frequently comes from land-based activities and many pollutants are deposited in estuaries and coastal waters. Here the pollutants invade marine food chains, building up their concentrations until they reach toxic levels.<br />Another thing that most people don’t know is that ⅔ of the total amount of acid rains fall in the sea, rising its pH, which will affect the ecosystems in a dreadful way.<br />Direct Pollution<br />Toxic waste not only harms the oceans and its life, but humans too. Radioactive waste, the most harmful waste, is stored in water ponds near to nuclear power stations until it is considered safe enough for disposal. Then, it is released directly into the sea. Toxic waste has a huge impact on our health and it may harm many animal and plant species that live in the ocean, as well. Why is it so harmful to us if it ends up in the ocean? It is because of the food chain: if a fish absorbs some kind of toxic pollution and we (humans) eat that fish, it can lead to food poisoning. <br />Ship pollution is one of the major causes of ocean pollution. This happens in the course of transportation of ships, when these discharge their cargo (accidently or deliberately). Tankers illegally cleaning their tanks while out at the sea and dumping the dirty water overboard cause significant oil pollution. It has been estimated that every year, around 7 million gallons of oil are accidently spilled into the oceans. Some consequences may be:<br />-slowing down the growth and hampers the life cycle of the coral reefs<br />-oil can also clog the gills of the fishes and blocks the sunlight.<br />Statistics reveal that an average sized cruise ship produces around a million gallons of waste in a week. <br />Garbage dumping is the dumping of human wastes, sewage water and plastics into the ocean. Whenever the sewage pipes overflow from heavy rains or floods, it can make its way into the ocean. Sewage pollution can also lead to oxygen depletion.<br />The dumping of plastic waste can lead to the death of fish and other sea animals due to suffocation.<br />
Illegal types of fishing <br />Fishing by poisoning is not only useless but harmful. Although it contains a high percentage of momentary success, it happens that these fish once ingesting the lethal substances such as mercury, lead or cyanide, can also poison humans. Fishing by led poisoning may also affect shorebirds.<br />Apart from fishing by poisoning, there is also fishing by dynamite explosion. This type of cruel fishing creates a high energy wave, killing the fish because they stop breathing, and their lungs are splayed.<br />Pirate fishing <br />The oceans have been the target of unregulated fishing for the past few centuries. People think that the ocean resources are unlimited, but they aren’t. For instance, it is estimated that 90% of the Mediterranean Sea’s wildlife has disappeared over the past 30 years. <br />Exploration of non-renewable resources <br />Non-renewable resources such as sand and coral reefs are very important for the ecosystems. Inert resources (natural substances formed by geologic processes that can be economically exploitable) sustain the majority of species in the oceans, offering them protection and food – this means their habitat.<br />Although the extraction of inert resources is an easy and profitable business, it has brought many consequences, for example:<br />
Destruction of the habitats and consequently, of nesting places (places where species like clown fish leave their eggs), which can guide to the extinction of species.
Alteration of sea currents could cause alternation of the mechanisms of temperature regulation in the Earth.
<br />So, what can I do to help?<br />
Read up a bit on the issues of overfishing, try to find some information regarding your local situation. Keep in mind that, because this is a global problem every situation changes from place to place.<br />
Know what you eat
If you eat fish make sure you know what you eat, and pick the ones with the lowest impact. Have a look at the Guide to Good Fish Guides for some tips.<br />
Spread the word
Conclusion <br />As you can see, the reasons for the oceans destruction are caused by humans. The first victims of the oceans pollution are marine species, the most prominent ones being fish and marine plants. Although it is difficult to measure, studies have shown that the populations of sea animals have declined, and the major cause is regarded to be ocean pollution.<br />Marine life is an important source of food for humans and, as a consequence, the depletion of marine life will lead to adverse effects on global food.<br />We are responsible for the change of habits, and we must act now! <br />