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Water Pollution

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Definition • Water pollution is any chemical, biological, or

physical change in water quality that has a harmful effect on living organism or makes water unsuitable for desired uses.

• It has been suggested that it is the leading worldwide cause of deaths and diseases,and that it accounts for the deaths of more than 14,000 people daily.

What is Water Pollution?

Any physical (temperature, oxygen), chemical (mercury), or biological (disease, sewage) change to water that adversely effects its use by living things .

و اإلحيائية للماء بحيث ٔ و الكيميائية ا ٔ ي تغير في الخصائص الفيزيائية ا ٔ ا

حياء فيه ٔ و حياة اال ٔ .تجعله غير مالئم الستخدام اإلنسان ا

Human and Natural Pollutants

Water is typically referred to as polluted when it is impaired by anthropogenic contaminants.

Natural phenomena such as volcanoes, alga blooms,storms, and earthquakes also cause major changes inwater quality.

WHAT ARE THE MAJOR SOURCES OF

WATER POLLUTION?

Sources of Water Pollution

Point source water pollution

• refers to contaminants that enter a waterway from a single,

identifiable source, such as a pipe or ditch.

• Examples of Point Sources

• Factories

• Sewage Treatment Plants

• Active and Abandoned Underground Mines

• Oil tankers

Non-Point Sources

refers to diffuse contamination that does not originate from a single discrete source.

Examples of Non-Point Sources• Acid Deposition, Parking lots• Runoff of Chemicals into Surface Water

• Croplands ,Livestock Feedlots

• Logged Forests,Urban Streets

• Lawns,Golf Courses

Types of Water Pollution

Physical poll. Chemical poll. Biological poll. Radiation poll. Surface water poll.Underground water poll.

Physical poll.

• Change in the standard properties of water, by changing temperature , salinity, or cloudy .

• Temperature: by neuclear factories .

• water becomes cloudy due to presence of some particulate matter such as sand or soil. Some plant material as algal-bloom may also be involved, that turns the consistency of water like a pea soup.

• Presence of some phosphates or nitrates may encourage the growth of blooms leading finally to a condition known as Eutrophication. This upsets the ecological balance.

Eutrophication• An increase in chemical nutrients —compounds

containing nitrogen or phosphorus —in an ecosystem, and may occur on land or in water. However, the term is often used to mean the resultant increase in the ecosystem's primary productivity(excessive plant growth and decay), and further effects including lack of oxygen and severe reductions in water quality, fish, and other animal populations.

Sources of Eutrophication

Eutrophication is apparent as increased turbidity in the northern part of the Caspian Sea.

Effects of Natural and Cultural Eutrophication

• Excessive amounts of algae can deplete dissolved oxygen content in the lake

• It can also cause bacteria to take over and produce toxic levels of hydrogen sulfide and flammable methane

Reduction Methods

• Use advanced waste treatment to remove nitrates and phosphates.

• Bans or limits on phosphates in household detergents and other cleaning agents.

• Soil conservation and land-use control to reduce nutrient runoff.

Hypoxia• Meaning 'low oxygen',

• hypoxia describes a state in which the amount of oxygen in seawater is less than 1.4 milliliters per liter (ml/l).

• Oxygen depletion can be the result of a number of factors including natural ones, but is of most concern as a consequence of pollution and eutrophication in which plant nutrients enter a river, lake, or ocean, phytoplankton blooms are encouraged.

Biological poll.

• It develops from the microorganisms that enter waters from such sources as human waste, food operations, meat packing plants and medical facilities etc.

– Giardia lamblia

– Salmonella

– Novovirus and other viruses

– Parasitic worms .

Radiation poll.

• Radiation leakage from Nuclear Reactors

• By getting rid of this waste, in the seas and oceans and rivers.

• Often does not happen this contamination of any change in the characteristics of natural water, which makes the species most dangerous, since absorbed by objects in the water, in most cases, and accumulate, and then transmitted to humans, while taking these neighborhoods, talk when many of the serious effects , including defect and the changes that occur in the genes.

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