Pollution of oceans is damaging the marine environment and is becoming a major problem. Marine environment is interesting for various reasons such as Sea food; Navigation; Adventure; Tourism etc,, Marine Pollution is harmful and its danger can be identified in a variety of ways.
Sources & causes of marine pollution
Marine pollution originates from one of two sources --- the land or the sea which are explained below:
Marine Oil Pollution: Oil is basically an important pollutant which destroys marine environment. The various sources of oil pollution are:
Run-off oil from streets; disposal of lubricants from machines; Off shore oil and gas exploitation from off-shore drilling; blowouts at off-shore drilling rigs; oil escaping under high pressure from a bore hole in the ocean floor. Waste chemicals, mud and accumulation of toxic substances in the ocean in theform of mercury, dioxin, PCBs, PAHs (Poly Aromatic Hydrocarbons), Radioactivity. benzene; xylene (colorless, flammable liquids) and heavy metals such as lead; copper; nickel, mercury also cause for marine pollution during the off shore drilling activities. Both dumping and exploitation of ocean resources cause ocean pollution also.
PAHs: It is a chemical compound and organic pollutant. These occur in oil, coal and tar deposits and are produced as byproducts of fuel burning. PAHs are lipophilic meaning they mix more easily in oil than water.
Eg for PAHs are: Acenaphthene; Anthracene; Benzopyrene; Chrysene; Coronene; Fluorene; Pyrene.
Other sources from land: The major sources of marine pollution originating from the land vary from country to country. Effluents are discharged either directly into the sea or enters the coastal waters through rivers. Thousands of barrels of oil burn when oil wells were set on fire. Tanker accidents on land carry oil to the nearby streams / canals and cause for marine Pollution. Due to burning of oil, smoke, SO2, NO2, CO is added towards atmospheric contamination.
The effects of oil pollution depend mainly on the following factors
Type of oil and its viscosity, amount / quantity released, distance covered, time, average water
temp etc.
Effects of Marine Pollution
|
SL
No |
Source |
Effect |
|
1 |
Sewage &
run- off from forestry; |
Depletes
oxygen in water causes killing of fishes. |
|
2 |
Sediments from
mining |
Sediments
clog in the gills of fishes |
|
3 |
Sewage
from municipalities, towns; cities etc… |
Contaminate
sea food |
|
4 |
Industrial
discharge; pesticides from farms |
Cause disease in
coastal marine life |
|
5 |
Oil from off
shore drilling; industries/ automobiles |
Low level
contamination kills larvae whereas high level contamination causes death for
sea fishes |
|
6 |
Litter
(rubbish), waste, plastics |
Marine
life disturbs |
|
7 |
Hot water from
power plants |
Kills
corals. |
Marine Pollution Abatement / Prevention & control measures of Marine pollution
The following are the some of the control measures for marine pollution:
1. Improving existing sewage disposal facilities
2. Ensuring individual houses have sewage disposal systems (such as septic tanks).
3. Large resorts should use and manage their own packaged treatment plants.
4. Marine planning and management should be considered as processes such as land – sea interaction; inter disciplinary co-operation; participation of public & private sector organizations; balance between protection and development public participation.
5. Oil tankers are double hulled ( two layered bottom ) to reduce the chance of oil leakage
6. Recycling facilities for used oil.