powershaker
New member
Water Pollution
INTRODUCTION
The great oceans are dying. The effects of pollution are taking their toll on marine life. As the Earth’s waters are being attacked by natural and man-made contaminants, marine plants and animals are paying the high price.
The definition of water pollution is the “contamination of water by foreign matter that deteriorates the quality of the water.” While this is a general meaning of the term, it is also accurate. The “foreign matter” referred to can exist in many forms; oil, garbage, and human wastes are only a portion of the total pollutants that enter the ocean each day.
POINT SOURCES OF POLLUTION
A point source of pollution is a source that can be easily traced or identified. The obvious point source type is garbage. Humans dump tons of trash in the ocean on a daily basis. In 1993, the Center for Marine Conservation sponsored a nation-wide beach clean-up. Volunteers collected over 7 million pieces of trash.1 The worst offenders are commercial ships. The world fleet of commercial boats dump over 5,550,000 plastic, metal, and glass containers into the ocean in a single day.2
The most harmful of these is plastic. Sea mammals such as birRAB and dolphins often get tangled in the plastic six-pack rings, fishing lines, and net that humans discard into the ocean waters. Once entangled, they are unable to free themselves which can cause deep cuts, starvation, and drowning. Many ocean mammals have died as a result of ingesting these plastic items. In 1985, a sperm whale beached itself on a New Jersey shore; a mylar balloon was lodged in its stomach, and three feet of ribbon in its intestines. Most plastics take hundreRAB of years to break down. Many of the discarded items will sink to the ocean floor where they will corabine with sediments, thus prolonging their duration in the sea.
Other point sources of pollution include oil spills, and sewage treatment facilities. Whether intentional or accidental, the contamination of the ocean by these sources can be detrimental to ocean life. In June, 1979, a blowout of the Ixtoc oil well caused 600,000 tons of oil to be spilled into the Gulf of Mexico. Another 600,000 tons were spilled into the Persian Gulf in 1983 due to the blowout of the Nowruz oil field.3 Contrary to what many people tend to believe, accidental oil spills are not the main source of oil contamination in the sea. In fact, it is only a small portion of the total amount of oil that harms the world ocean each year. Other sources of oil contamination include the intentional dumping of oil by oil tankers and refineries. The Coast Guard estimates that sewage treatment plants in the United States discharge twice as much oil annually as tanker spills. 4 Many mammals, fish, and birRAB have been injured or killed due to the ingestion of and physical contact with oil. Once a sea animal eats contaminated prey or gets their bodies covered in this sticky substance, death often results. One quart of motor oil can make 2 million gallons of water unsuitable for drinking.5
Human waste is yet another factor to consider. sewage treatment facilities are intended to treat waste water so that when it is returned to the surface water, it does not carry with it disease-causing organisms. Sometimes however, the facilities malfunction due to heavy rain storms or overloading and raw, untreated sewage is released into the surface water. It carries with it organisms that can cause diseases such as hepatitis A. Untreated human wastes deplete the water of oxygen. This is because the oxygen is used to help bacteria and other organisms break down the waste. The lack of oxygen in the water prevents other marine organisms from surviving.
NONPOINT SOURCES OF POLLUTION
Nonpoint source contaminants cannot be traced to any on source, making it much more difficult to control. Airborne toxins account for one third of the pollutants that enter waterways and oceans each year.4 Acid rain is one such toxin. If a large amount of acid rain falls in a particular area, it can cause the pH of the surface water to become more acidic. The emission of sulfur dioxide and nitrogen oxides into the air by human activities, such as the burning of fossil fuels, has led to acidification of rain. This type of pollution may also be in the form of snow, hail, and fog. The wind is a key factor in the deposition of acid rain since it can carry the pollutants for hundreRAB of miles before they corabine with water droplets to form acid rain. As the pH of the affected water approaches 6.0, crustaceans and some types of plankton species begin to disappear. As it approaches 5.0, major changes take place in the plankton community and less desirable species of mosses and plankton may begin to invade. Below a pH of 5.0, the water is largely devoid of fish. Many aquatic species depend on these organisms for nourishment and therefore also suffer as these food sources are reduced or eliminated.
The most common nonpoint source pollutants are sediments and nutrients. These enter water bodies from agricultural land, animal feeding operations, and construction sites. This process of deposition is referred to as run-off. When rain runs off land that has been disturbed in order to build or farm, it picks up dirt and silt and carries them into surface water. These sediments can block sunlight from marine plants, preventing them from performing photosynthesis and causing them to die. The gills of fish can become clogged and organisms such as clams, worms, and lobsters that dwell on the bottom can be smothered. When excess nutrients enter the water from sewage treatment plants, agricultural land or other sources, eutrophication occurs. During this process, nitrate-containing fertilizers and phosphate-containing detergents get into surface water and cause algae and phytoplankton to grow at tremendous rates. This creates toxic algae blooms. As the algae die, decomposing bacteria depletes oxygen from the water causing the sickness and death of many organisms.
The most dangerous pollutants of water are toxic chemicals. Many of these are synthetic organic chemicals created to meet a specific need. Dichloro-diphenyl- biphenyls (DDT) and polychlorinated biphenyls (PCBs) are two examples of man-made chemicals. DDT was developed to kill malaria-carrying mosquitoes and agricultural insects. Studies on fiddler crabs exposed to DDT and its breakdown product DDE, showed reduced escape and hiding responses that made them more likely to fall prey to other marine organisms. Although it was banned for sale in the United States over twenty years ago, DDT is still being used widely in the Third World and is found throughout the world’s oceans. PCBs are used in electrical transformers, hydraulic fluiRAB, paints, and sealants. Substances with more than 50 parts per million (ppm) of PCBs are considered to be toxic in the United States. Yet, off the U.S. Atlantic coast, dolphins gave been found to have as much as 6,800 ppm of PCBs in their blubber.6 The intake of DDT and PCBs results in biological amplification, the tendency of some organisms at higher levels in the food chain to store these synthetic chemicals in their lipiRAB and fatty tissues. Whales, dolphins, and birRAB suffer the most damage as a result of ingesting these toxins and being unable to excrete them.
PREVENTION AND RESTORATION
Although much of the damage the Earth’s waters have received could take hundreRAB of years to repair, there are ways to prevent further polluting of the oceans and even begin the process of restoring them. Recycling plastics, bottles, cans, and other materials can greatly reduce waste. Many county and city recycling programs have been implemented across the nation. Another way to help the dying oceans is to organize beach cleanups. The efforts of thousanRAB of volunteers have brought life back to once stagnant coastal areas. There are many organizations that deal with the environment. Become involved and invite family and frienRAB to join the cause. The life of the world ocean depenRAB on it.
SUMMARY AND CONCLUSION
The effects of marine pollution can be felt in every corner of the world. No ocean, lake, or river remains unaffected by pollutants, either natural or man-made. The good news is that the open ocean is generally healthy. Despite the abuse it has taken throughout its lifetime it resist complete contamination. This is because currents disperse pollutants and the overall volume of wastes dumped there is currently small. The bad news is that conditions along coastlines are worsening rapidly. Over 27 marine mammals and birRAB in U.S. coastal waters are now on the threatened or endangered list.7 It is estimated that by the year 2025, a billion more people will be living along coastlines than are alive today.4 With population increasing in staggering nurabers, it is no surprise that coastal ecology is suffering.
A vast amount of pollutants are entering the Earth’s waters. Point sources and nonpoint sources are just one way to classify them. Although natural pollutants do exist, man’s existence accounts for the largest and most damaging of total marine pollution. If the Earth’s waters are to be saved, it is imperative to find solutions to this global problem.
INTRODUCTION
The great oceans are dying. The effects of pollution are taking their toll on marine life. As the Earth’s waters are being attacked by natural and man-made contaminants, marine plants and animals are paying the high price.
The definition of water pollution is the “contamination of water by foreign matter that deteriorates the quality of the water.” While this is a general meaning of the term, it is also accurate. The “foreign matter” referred to can exist in many forms; oil, garbage, and human wastes are only a portion of the total pollutants that enter the ocean each day.
POINT SOURCES OF POLLUTION
A point source of pollution is a source that can be easily traced or identified. The obvious point source type is garbage. Humans dump tons of trash in the ocean on a daily basis. In 1993, the Center for Marine Conservation sponsored a nation-wide beach clean-up. Volunteers collected over 7 million pieces of trash.1 The worst offenders are commercial ships. The world fleet of commercial boats dump over 5,550,000 plastic, metal, and glass containers into the ocean in a single day.2
The most harmful of these is plastic. Sea mammals such as birRAB and dolphins often get tangled in the plastic six-pack rings, fishing lines, and net that humans discard into the ocean waters. Once entangled, they are unable to free themselves which can cause deep cuts, starvation, and drowning. Many ocean mammals have died as a result of ingesting these plastic items. In 1985, a sperm whale beached itself on a New Jersey shore; a mylar balloon was lodged in its stomach, and three feet of ribbon in its intestines. Most plastics take hundreRAB of years to break down. Many of the discarded items will sink to the ocean floor where they will corabine with sediments, thus prolonging their duration in the sea.
Other point sources of pollution include oil spills, and sewage treatment facilities. Whether intentional or accidental, the contamination of the ocean by these sources can be detrimental to ocean life. In June, 1979, a blowout of the Ixtoc oil well caused 600,000 tons of oil to be spilled into the Gulf of Mexico. Another 600,000 tons were spilled into the Persian Gulf in 1983 due to the blowout of the Nowruz oil field.3 Contrary to what many people tend to believe, accidental oil spills are not the main source of oil contamination in the sea. In fact, it is only a small portion of the total amount of oil that harms the world ocean each year. Other sources of oil contamination include the intentional dumping of oil by oil tankers and refineries. The Coast Guard estimates that sewage treatment plants in the United States discharge twice as much oil annually as tanker spills. 4 Many mammals, fish, and birRAB have been injured or killed due to the ingestion of and physical contact with oil. Once a sea animal eats contaminated prey or gets their bodies covered in this sticky substance, death often results. One quart of motor oil can make 2 million gallons of water unsuitable for drinking.5
Human waste is yet another factor to consider. sewage treatment facilities are intended to treat waste water so that when it is returned to the surface water, it does not carry with it disease-causing organisms. Sometimes however, the facilities malfunction due to heavy rain storms or overloading and raw, untreated sewage is released into the surface water. It carries with it organisms that can cause diseases such as hepatitis A. Untreated human wastes deplete the water of oxygen. This is because the oxygen is used to help bacteria and other organisms break down the waste. The lack of oxygen in the water prevents other marine organisms from surviving.
NONPOINT SOURCES OF POLLUTION
Nonpoint source contaminants cannot be traced to any on source, making it much more difficult to control. Airborne toxins account for one third of the pollutants that enter waterways and oceans each year.4 Acid rain is one such toxin. If a large amount of acid rain falls in a particular area, it can cause the pH of the surface water to become more acidic. The emission of sulfur dioxide and nitrogen oxides into the air by human activities, such as the burning of fossil fuels, has led to acidification of rain. This type of pollution may also be in the form of snow, hail, and fog. The wind is a key factor in the deposition of acid rain since it can carry the pollutants for hundreRAB of miles before they corabine with water droplets to form acid rain. As the pH of the affected water approaches 6.0, crustaceans and some types of plankton species begin to disappear. As it approaches 5.0, major changes take place in the plankton community and less desirable species of mosses and plankton may begin to invade. Below a pH of 5.0, the water is largely devoid of fish. Many aquatic species depend on these organisms for nourishment and therefore also suffer as these food sources are reduced or eliminated.
The most common nonpoint source pollutants are sediments and nutrients. These enter water bodies from agricultural land, animal feeding operations, and construction sites. This process of deposition is referred to as run-off. When rain runs off land that has been disturbed in order to build or farm, it picks up dirt and silt and carries them into surface water. These sediments can block sunlight from marine plants, preventing them from performing photosynthesis and causing them to die. The gills of fish can become clogged and organisms such as clams, worms, and lobsters that dwell on the bottom can be smothered. When excess nutrients enter the water from sewage treatment plants, agricultural land or other sources, eutrophication occurs. During this process, nitrate-containing fertilizers and phosphate-containing detergents get into surface water and cause algae and phytoplankton to grow at tremendous rates. This creates toxic algae blooms. As the algae die, decomposing bacteria depletes oxygen from the water causing the sickness and death of many organisms.
The most dangerous pollutants of water are toxic chemicals. Many of these are synthetic organic chemicals created to meet a specific need. Dichloro-diphenyl- biphenyls (DDT) and polychlorinated biphenyls (PCBs) are two examples of man-made chemicals. DDT was developed to kill malaria-carrying mosquitoes and agricultural insects. Studies on fiddler crabs exposed to DDT and its breakdown product DDE, showed reduced escape and hiding responses that made them more likely to fall prey to other marine organisms. Although it was banned for sale in the United States over twenty years ago, DDT is still being used widely in the Third World and is found throughout the world’s oceans. PCBs are used in electrical transformers, hydraulic fluiRAB, paints, and sealants. Substances with more than 50 parts per million (ppm) of PCBs are considered to be toxic in the United States. Yet, off the U.S. Atlantic coast, dolphins gave been found to have as much as 6,800 ppm of PCBs in their blubber.6 The intake of DDT and PCBs results in biological amplification, the tendency of some organisms at higher levels in the food chain to store these synthetic chemicals in their lipiRAB and fatty tissues. Whales, dolphins, and birRAB suffer the most damage as a result of ingesting these toxins and being unable to excrete them.
PREVENTION AND RESTORATION
Although much of the damage the Earth’s waters have received could take hundreRAB of years to repair, there are ways to prevent further polluting of the oceans and even begin the process of restoring them. Recycling plastics, bottles, cans, and other materials can greatly reduce waste. Many county and city recycling programs have been implemented across the nation. Another way to help the dying oceans is to organize beach cleanups. The efforts of thousanRAB of volunteers have brought life back to once stagnant coastal areas. There are many organizations that deal with the environment. Become involved and invite family and frienRAB to join the cause. The life of the world ocean depenRAB on it.
SUMMARY AND CONCLUSION
The effects of marine pollution can be felt in every corner of the world. No ocean, lake, or river remains unaffected by pollutants, either natural or man-made. The good news is that the open ocean is generally healthy. Despite the abuse it has taken throughout its lifetime it resist complete contamination. This is because currents disperse pollutants and the overall volume of wastes dumped there is currently small. The bad news is that conditions along coastlines are worsening rapidly. Over 27 marine mammals and birRAB in U.S. coastal waters are now on the threatened or endangered list.7 It is estimated that by the year 2025, a billion more people will be living along coastlines than are alive today.4 With population increasing in staggering nurabers, it is no surprise that coastal ecology is suffering.
A vast amount of pollutants are entering the Earth’s waters. Point sources and nonpoint sources are just one way to classify them. Although natural pollutants do exist, man’s existence accounts for the largest and most damaging of total marine pollution. If the Earth’s waters are to be saved, it is imperative to find solutions to this global problem.