A group of American scientists discovered that in the Gulf of Mexico off the coast of the United States formed a large dead zone – a section of oxygen deprived of oxygen with an area of about 23 thousand square kilometers. According to the researchers, it was formed because of agricultural waste entering the Gulf through the Mississippi River. This is reported by the publication Gizmodo.
The appearance of dead zones is a typical phenomenon for the Gulf of Mexico. Their average size is 15 thousand square kilometers. In 2002, researchers recorded one of the largest anoxic regions, whose area reached 22 thousand square kilometers. However, the new dead zone, which appeared this year, broke this record. It is 4.6 times the permissible limit established by experts of the Gulf Hypoxia Task Force, whose purpose is to reduce the level of pollution of the Mississippi River.
Reducing the concentration of oxygen in water (this condition is called hypoxia) is due to the fact that the abundance of nutrients in the waters polluted with fertilizers and soil particles leads to a massive growth of algae. The death and decay of the latter is the cause of the depletion of oxygen and the death of sea creatures. In the world there are more than 400 hypoxic zones, but the site in the Gulf of Mexico is the largest of them.