5 October 2016
Toxic Algae Blooms Linked to
Over-Fertilization and Climate Change
Recent blooms of toxic algae in southern Florida, which
have provoked Governor Rick Scott to announce a state of emergency, may be tied
to fertilizer chemicals from agricultural and residential origins.
and beaches along Florida’s Treasure Coast, Lake Okeechobee, and the Everglades
have been experiencing massive blooms of toxic algae since May. The
cyanobacteria algae—described as thick, pea-green, and foul-smelling—is intensely toxicand poses health risks to people and wildlife
in the area. At its peak, the bloom in Lake Okeechobee covered 33 square miles—or about one-third of the lake's surface. One source estimates the
total area of the algae to be roughly the size of Miami.
impact of these algae blooms has already proven disastrous. Tourism, a main
source of income for residents around Lake Okeechobee and along the coast, is
down. Contact with toxic algae blooms “can affect the gastrointestinal system, liver, nervous system, and skin.”
Fish are dying, and many have raised concerns about manatees and other large
wildlife in the area.
what caused this massive outbreak? The blooms spread, in part, due to
flood-control measures taken by the U.S. Army Corps of Engineers; to prevent
Lake Okeechobee from overflowing earlier this year, the Corps released large
amounts of water from the lake into nearby estuaries. According to a statement, these actions “upset the freshwater-saltwater mix
in the estuaries” and contributed to the spread of the toxic blooms.
the key factor seems to be high levels of nutrients (like nitrogen and
phosphorous) in the water. According to a spokeswoman for Earthjustice,
speaking to CNN: "The algae outbreaks are triggered by
fertilizer sewage and manure pollution that the state has failed to properly
regulate. It's like adding miracle grow to the water and it triggers massive algae
the water in Lake Okeechobee is contaminated by nutrient-rich manure and
waste-filled runoff from nearby farms and houses. Exacerbated by hot summer
weather, these conditions create an ideal habitat for toxic algae. Some fear that,
once the algae die off, large swaths of affected water could turn into oxygen-deficient “dead zones.”Over-fertilization
and poor land management, coupled with various manifestations of climate
change, mean that algae blooms are becoming much more than a seasonal
annoyance: these blooms are threatening ecosystems and biodiversity in the
Army Corps of Engineers has drastically reduced the amount of lakewater flowing
into nearby estuaries, but the root of the problem—the cause of the high
nitrogen and phosphorous levels—is less immediately remediable. Next steps
include a focus on responsible agriculture and gardening practices to reduce
fertilizer runoff, as well as efforts to combat climate change.
light of these recent events, the Everglades Foundation has launched a ten million dollar prize for
developing a cost-effective, sustainable technology to reduce phosphorous
levels in the water.