Scientists use automatic sensors on portable platforms to study how
harmful algal blooms develop in Florida's coastal waters.
Time and resources limit the information that marine scientists
can collect from Florida's vast coastal waters. Sampling weekly or
monthly provides only snapshots of coastal conditions. To acquire
the kind of real-time information that is invaluable, researchers
need to collect biological and physical data every hour, even at
night or during storms.
In 2000, the FWC's Fish and Wildlife
Research Institute (FWRI) built a floating platform with automatic
sensors to provide a variety of information about Florida's coastal
ecosystems. Researchers named the platform
MERHAB Autonomous
Research Vessel for
In-Situ Sampling, or MARVIN. MERHAB is the acronym
for Monitoring and Event Response for Harmful Algal Blooms, a
National Oceanic and Atmospheric Administration (NOAA) program that
provided the initial funding; in situ is a Latin term
referring to the study of a process in the environment where it
naturally occurs.
The solar-powered MARVIN platform, first deployed for three
years in the St. Johns River, was based on a pontoon boat for
portability and ease of maintenance. Because the first MARVIN was
so successful, the U.S. Army Corps of Engineers and the state of
Florida provided funding to build two additional MARVINs. Over the
next eight years, FWRI deployed the platforms in the upper part of
the Caloosahatchee River, near the mouth of the Caloosahatchee
estuary, and near Long Boat Key in Sarasota Bay. One of the
original floating platforms is being rebuilt for use in Old Tampa
Bay.
The MARVIN systems take most measurements every
hour at the water surface and just above the bottom. In the water,
these systems measure salinity, temperature, chlorophyll and
phycocyanin fluorescence (indicators of algal biomass), pH,
turbidity (an indicator of water clarity), dissolved oxygen,
nitrogen concentrations, and the speed and direction of
currents. Above the water, the systems measure wind speed and
direction, rainfall, barometric pressure, humidity, and visible
light. Each MARVIN transmits information through satellites to the
Coastal
Ocean Monitoring & Prediction System Web site, where anyone
can see and use the data.
A new generation of monitoring system uses a single box that can
be mounted on docks or seawalls for easy access. These new
platforms, together with the remaining MARVIN, make up the Harmful
Algal Bloom Marine Observation Network (HABMON). The Florida
Department of Environmental Protection, which manages NOAA's
Florida Coastal Management Program, is a partner in the program.
FWRI also cooperates with the University of South Florida, Sarasota
County, and Mote Marine Laboratory to operate HABMON platforms on a
fixed tower near Port Manatee in Tampa Bay and on a dock in
Sarasota Bay.
HABMON will be valuable in
monitoring long-term environmental changes in Florida--helping, for
example, to determine whether increasing pollution stimulates
harmful algal blooms. Scientists can see short bursts of nutrients
as they enter the ecosystem and gather evidence on their origins.
The HABMON platforms can also demonstrate the effects of regulatory
changes on HABs to help determine the most effective policies for
improving the environment. The platforms are an effective
tool to enhance understanding of factors contributing to harmful
algal blooms.