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by Barry Nerhus

· Environment,Climate Change,Oceans,Ocean Sciences

Sustainable fishing has become a trend for recreational and commercial fishermen. However, few people know about the dynamic chemical composition of the ocean floor. Most fishermen who participate in bottom trawling do not understand how much carbon is released from the floor itself. It’s important to know how much this practice contributes to increased levels of carbon in the atmosphere if we are to save ocean life. 

The Detrimental Process of Bottom Trawling

 Bottom trawling is the process of dragging a trawl, or a large fishnet, across the seafloor. The act of dragging is said by experts to be wasteful in time, energy, and natural resources. As the net is dragged, it can destroy fragile habitats and become dangerous to certain underwater species. 

Where Carbon is Found Underwater 

Roughly 90 Petagrams of carbon moves back and forth between the world’s oceans and the atmosphere. Phytoplankton undergoes photosynthesis, in which it consumes carbon dioxide and stores carbon. But, as the plants become buried in the seafloor, they produce massive reservoirs of carbon. The ocean contains a diverse variety of chemicals, from bicarbonate, to carbon, and hydrogen. There are more chemicals in some deep parts of the ocean than there are in the air or earth. 

How Carbon is Increased 

Scientific experts say that bottom trawling disrupts the sea environment and releases its underground supply of carbon. The carbon is converted into carbon dioxide (CO2) and released into the air. One study claims that trawling leaves behind a carbon footprint that is comparable to commercial air travel. 

A team of marine biologists and climate researchers stated that bottom trawling releases one gigaton of carbon into the atmosphere every year. This is equal to the one billion tons of carbon released during commercial air travel. They are looking at which parts of the ocean need the most protection from trawling and alternative methods to trawling. 

Unfortunately, many fishermen who participate in bottom trawling are not familiar with chemistry and marine biology. They are not environmentalists and do not understand the full global impact of their fishing methods. Carbon emissions contribute to global warming that results in extreme, unpredictable weather patterns. In the future, fishermen are encouraged to abandon the practice of bottom trawling and replace it with any environmentally-friendly fishing methods available.

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