The 'dead zone' spreads across the Gulf of Mexico

US researchers found that the area known as the "dead zone" in the Gulf of Mexico increased in size.

"Dead zone" in the Gulf of Mexico has expanded its area

According to scientists at the US National Oceanic and Atmospheric Administration (NOAA), the dead zone in the Gulf of Mexico has expanded, with an area of ​​more than 10,400 km2 covered. The cause of this situation is due to heavy rains in central America in July.

Dead zones in the Gulf of Mexico have expanded.(Photo: NOAA.)

Dead zone is an area with low oxygen or no oxygen, which can kill fish and marine mammals if they enter the lack of oxygen.

Last year, the dead area in the Gulf of Mexico was 8,130 km2. The latest measurements show that this dead zone is larger than average and wider than NOAA's annual prediction.

Of the more than 550 dead zones in lakes and oceans around the world, the dead zone in the Gulf of Mexico is the second largest area of ​​human oxygen deficiency. Water that suffocates here is a consequence of the strong growth of phytoplankton causing oxygen depletion. They were driven by high levels of nitrogen and phosphorus due to agricultural activities and waste disposal on the Mississippi River .

When phytoplankton die and sink to the bottom, the bacteria digest them and absorb more oxygen in the water. This oxygen-losing water remained in place until the storms stirred the aquifers and supplemented the dead zone with oxygen.

" Because the models based mainly on nitrogen from the Mississippi River in May, heavy rains in June and higher levels of river emissions in July can help explain the increase in the size of the region. die, " UPI yesterday quoted Nancy Rabalais, executive director of the University of Louisiana Maritime Research Center.

Along with rain, wind, temperature and ocean currents also affect the size and movement of the dead zone in the Gulf of Mexico. Previous research has shown that lack of oxygen in this area leads to destruction of habitats , replacement of species and loss of fertility of many fish.