Fish are Friends not Garbage

The debris in the ocean make the fish sick and they eventually die. However, fish are important for the environment because their excretions "play a key role in maintaining the ocean's delicate pH balance" (www.newscientist.com). Bony fish excrete lumps of calcium carbonate known as "gut rocks". It plays a major part in buffering the carbon dioxide that acidifies the seawater. These gut rocks have a chemical structure that is very soluble in seawater. When fish drink salt water, they consume a lot of calcium, which causes them to excrete more or less calcium carbonate, depending on the size of the fish and the temperature of the water. Different environments are better for different fish but in general, "[f]or a given total mass of fish, smaller fish produce more then bigger fish, and fish at higher temperatures produce more than fish at lower temperatures" (www.newscientist.com). Warmer temperatures create the optimum environment for the most efficient calcium carbonate production. Therefore, as the temperature increases, so does the rate at which calcium carbonate is produced. Another problem besides the garbage killing the fish is over fishing. Over fishing is a concern because it depletes our food stock, which also results in a reduction of this valuable carbon buffer needed for our ocean and environment. This is important because some other marine animals build their external skeleton on calcium carbonate, which is excreted by fish.

The ocean and atmosphere are constantly in contact and any change in one of them directly affects the other. They share water, gases, and energy. Consequently, the pH of the ocean is important since it affects the carbon cycle. This cycle is a pathway to exchange carbon and there are four main reservoirs: the atmosphere, the terrestrial biosphere, the oceans, and sediments. Carbon is constantly being exchanged between the atmosphere and the ocean.

The series of reactions that CO₂ participates in when it enters the ocean are:

Solution:

• CO₂(atmospheric) ⇌ CO₂(dissolved)

Conversion to carbonic acid:

• CO₂(dissolved) + H₂O ⇌ H₂CO₃

First ionization:

• H₂CO₃ ⇌ H⁺ + HCO₃⁻ (bicarbonate ion)

Second ionization:

• HCO₃⁻ ⇌ H⁺ + CO₃⁻⁻ (carbonate ion)

The lack of fish in the ocean results in a decrease of the pH in the ocean, and then increase of carbon dioxide. This would mean that the ocean is acidic and it will lead to acid rain to faster decaying of buildings and it also damage trees. Acid rain weakens a tree and thus harming their leaves and limiting the nutrients that are available for them.