By Associated Press
Cocodrie LA – The annual "dead zone" off the Louisiana and Texas coasts is not quite as big as predicted earlier this year.
But at 79-hundred square miles, it's still the third-largest ever mapped.
The Louisiana-Texas dead zone is the world's second-largest area of deprived oxygen levels in water. Experts say this year's version is about seven percent smaller than had been earlier expected.
The area with almost no oxygen was about the size of Connecticut and Delaware together.
Hypoxia occurs when still weather lets fresh water pouring in from the Mississippi River float above the heavier salt water in the Gulf. Algae die and fall to the bottom, where their decay uses oxygen faster than it is brought down from the surface. Eventually, the lower layer holds too little oxygen for aquatic life.
Nitrogen, from sources including fertilizer, erosion and sewage, speeds up the process by feeding algae.
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