User:Hjnelson02/Ammonia pollution

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(In aquatic settings, ammonia causes nitrogenous oxygen demand, eutrophication, and changes in fish health. Nitrogenous biological oxygen demand (NBOD) occurs as a direct result of nitrification (see terrestrial effects). Dissolved oxygen (O2) is used in nitrification to react with NH3. This results in less O2 available to organisms that depend on it. Nitrification also releases nitrate which leads to eutrophication as in terrestrial settings. Nitrophilous algae and macrophytes create large blooms in standing water. This puts stress on resources and also can indirectly poison organisms through toxic algae formation. In contrast, ammonia can also directly harm organisms with permeable skin if they absorb it. Fish kills and changes in fish growth, gill condition, organ weights, and hematocrit (red blood cell) levels are linked to ammonia exposure.

High levels of ammonia present in water has been shown to increase pH, causing lethal effects on fish and other aquatic life. Cells in organisms have a protective membrane preventing excess amounts of ammonia from entering the cell by only allowing un-ionized ammonia to freely flow into the cell. Increased pH also increases the amount of un-ionized ammonia in water, which causes increases ammonia concentrations in the cells of fish. A study on water pH showed toxic manifestations on fish in 70 minutes when kept in water at a high pH containing 10.1 mgm. of ammonium sulfate.)

The information below is all new and written by me. Above is what is currently published in the aquatic effects section.

Lead
Ammonia also has effects on aquatic ecosystems and decreases the biodiversity. Ammonia is toxic to aquatic life which leads to increased amounts of fish deaths. Ammonia pollution also leads to eutrophication. Eutrophication is the growth of algae that kills other aquatic life and creates dead zones. Ammonia pollution affects freshwater and salt water ecosystems differently due to physical and chemical differences.

Aquatic effects
Ammonia seeps into aquatic ecosystem in many different ways from both anthropogenic (waste water, fertilizers, and industrial waste) and natural (Nitrogen fixation and air deposition) sources. Ammonia is toxic to most aquatic life including fish, corals, and planktonic crustaceans. Ammonia can have 2 different forms in water.

This reaction is showing how ammonia changes into ammonia in water and generates a hydroxide ion. The form that the ammonia takes in the water also depends on the pH and temperature. Waters that are more basic have more ammonia compared to the amount of ammonium. Ammonia is directly toxic to aquatic life while ammonium is not. This is because ammonia can diffuse across cell membranes but ammonium can't. This means that the more basic the waters, the more toxic ammonia pollution will be to the aquatic life.

Freshwater effects
Freshwater systems are commonly limited by nitrogen. This means that increases in nitrogen in freshwater ecosystems can increase the primary productivity of plants and algae. When too much nitrogen is added to the water, the algae in the water can increase their output so rapidly that eutrophication occurs. Eutrophication is an increase in algal growth which causes the oxygen dissolved in the water to decrease. This decrease creates hypoxic waters that cause the death of other aquatic life like fish. This decreases the amount of biodiversity in the waters where this occurs.

Ammonia is also directly toxic to fish and as the amount of ammonia increases, the more that accumulates in their bodies and it becomes harder to for the animals to remove it from their bodies. Freshwaters tend to have a wide range of pH values from 6.5 to 9. Freshwaters that have a higher pH would be more sensitive to increases in ammonia due to the balance between ammonia and ammonium and the aquatic life would be more affected. The ammonia causes stress on the fish and damages internal organs which will eventually lead to death.

Saltwater effects
Saltwater systems are also commonly limited by nitrogen. Eutrophication can also occur in saltwater due to increases in ammonia available, however it is more common in freshwaters because they have limited circulation and shallower waters. The pH of the ocean tends to be about 8.1 which means that more of the ammonia found in the ocean waters would be in the form of ammonia and not ammonium. This also means that there are more toxic effects than other waters that are more acidic.

Ammonia in saltwater ecosystems will have similar effects on fish as ammonia in freshwater ecosystems. Another aquatic animal that that is affected by increasing amounts of ammonia is coral. Coral are very important for diversity in oceans and increasing concentrations of ammonia in the water is harming the bacteria that are found on the coral. The coral and bacteria are in a symbiotic relationship and the death of the bacteria leads to the bleaching of the coral and death. Corals support biodiversity in the ocean and the loss of coral reefs leads to a decrease in biodiversity.