Annual seaweed bloom on Florida’s Atlantic coast is thick and may worsen

Annual seaweed bloom on Florida’s Atlantic coast is thick and may worsen

Sunday, July 29, 2018

Seaweed accumulates on a beach in St. Lucie County (Credit: Patrick Dove | TCPalm.com)

Scientists say the annual summer seaweed bloom along Florida’s Atlantic coast could grow to record dimensions by fall.

Satellite imagery from a project at the University of South Florida shows that the seaweed bloom in June was three times larger than the bloom in June 2015, the largest ever in the sixth month of the year.

The blooms peak in late summer and early fall, piling seaweed in brown bunches on and along Florida beaches.

Small amounts restrict beach erosion, but too much seaweed kills sea grass and marine life by absorbing oxygen in the water as it decomposes.

Seagrass also emits smelly hydrogen sulfide gas and serves as habitat for jellyfish and other tiny critters that sting and bite.

Brian LaPointe, a professor at Florida Atlantic University who has studied seaweed since the late 1980s, recently saw a six- to 10-foot ribbon of seaweed as much as a half-foot thick on his favorite beach on North Hutchison Island in Fort Pierce.

LaPointe said the annual seaweed bloom is comparable to the recurring blue-green algae bloom in Lake Okeechobee, which nourishes algae with phosphorus and nitrogen runoff from farms and towns.

The primary cause of the seaweed bloom is phosphorus in grains of Saharan sand that winds carry off the west coast of Africa, according to LaPointe, who works at FAU’s Harbor Branch Oceanographic Institute in Fort Pierce.

Many scientists believe the Atlantic seaweed bloom comes from the Gulf of Mexico, where the Mississippi River deposits nutrients from agricultural runoff and other upstream sources. [TCPalm.com] – Mike Seemuth


Source: The Real Deal