[Coral-List] Lyngbya bloom

[Mark Vergara]

Following on Gene Shinn's info on *Lyngbya* bloom stimulated by iron in the
water, then it would explain the overgrowth of *Lyngbya* on a ship grounding
site we surveyed in northwest Philippines were the ship was not yet removed.

Mark Vergara
The Marine Science Institute
University of the Philippines


Date: Fri, 16 Apr 2010 18:05:36 -0400
From: Gene Shinn <eshinn at marine.usf.edu>
Subject: [Coral-List] Lyngbya bloom
To: coral-list at coral.aoml.noaa.gov
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Kevin, Recent studies at the Smithsonian Lab in Ft Pierce found  that
iron is the primary nutrient that  that stimulates Lyngbya growth.
The question is what is the source of iron? Sewage is not normally a
source of iron. One  source is African dust. The dust  contains
between 5 and 6 percent iron. The dust blows in to south Florida
every summer beginning in June and lasting until November. Due to
climate changes in North Africa and increased use of water (Lake Chad
once 100 miles across is now about 10  miles across) the amount of
dust blowing in from Africa began increasing in the early 1970s and
peaked in 1983 and 84. 1983 and 1984 was when Lyngbya  as well as
various green algae proliferated on the reef tract and in Florida
Bay. Another peak year for dust was 1998. Coral lovers will know what
happened during those years. The amount of dust leaving Africa is
around 1 billon tons each year of which hundreds of Millions of tons
reach our shores. For example the amount of African dust reaching
Miami  exceeds EPA particulate standards several times a year during
summer months. Sorry, not much we can do about it. Gene