South Florida Ecosystems
ISSUE
The impacts of population shifts to U.S. coastal regions, including habitat
modification, nutrient and toxic chemical inputs, and fresh water diversions
are poorly understood. Examining the combined interactions of natural and
human-induced stressors, (e.g., harmful algal blooms (HABs), nutrients or
toxics loadings, and habitat loss) is a new approach to studies of coastal
degradation that have traditionally focused on individual factors. Better
understanding of these cumulative effects and development of integrative approaches
to manage these effects is needed for use and protection of coastal resources.
The Coastal Ocean Program (COP) is participating in an extensive federal-state
effort to address these needs and restore the south Florida ecosystem. COP
is quantifying and modeling existing conditions and ecological relationships
along the south Florida coast (including Biscayne Bay, Florida Bay, Florida
Keys, and west Florida).
Sattelite Image of Florida Bay
APROACH
The Interagency Florida Bay Science Program seeks to develop an understanding
of the structure and function of coastal south Florida in the context of its
restoration. Restoration of coastal south Florida includes the re- establishment
and maintenance of the natural diversity, abundance and behavior of the marine
and estuarine flora and fauna. A major factor controlling these parameters
appears to be freshwater and nutrient inputs. However, the proposed additional
flow of fresh water through the Everglades may not be sufficient. Timing,
location, type and quality of input are all critical parameters, and are,
in part, dependent upon land-based restoration activities. Achieving a predictive
capability of the physics and ecology of coastal south Florida will allow
for testing management strategies, which is the ultimate goal of the COP research.
COP's south Florida research activities include empirical studies, development
and testing of models, assessing risks, and evaluation of ecological responses
of the south Florida coastal marine ecosystem. These activities are grouped
into the following topical areas: landscape-seascape modeling of human-environment
linkages in Biscayne Bay and adjacent coral reefs; research and modeling of
physical and biological conditions in Florida Bay and their influence on coral
reefs; and developing predictive models for forecasting toxic dinoflagellate
blooms. The landscape-seascape program is focused on designing individual
ecosystem component models to characterize physical, chemical and biological
stressors, and to develop and validate new indicators of stress for key organisms
and ecological processes.
The Florida Bay studies, designed to compliment other federal and state activities
underway, will provide decision-makers with the tools to examine the risks
to ecological resources of Florida Bay. This program also includes Community
Education & Outreach activities that connect research
and ecosystem management with the diverse public audiences and interests.
COP's HAB projects in this region focus on the annual toxic phytoplankton
bloom of Gymnodinium breve. They will provide a regional overview
of factors favoring development and persistence of the "red-tide" bloom
as well as provide critical information on potentials for control of
the bloom species and its impacts on coastal resources (see
COP fact sheet on HABs).
ACCOMPLISHMENTS
Researchers have developed a series of initial conceptual models and computer
simulation models that quantify and characterize existing conditions and ecological
relationships along the south Florida coast, including Biscayne Bay, Florida
Bay, Florida Keys, and west Florida. These include: Biscayne Bay hydrodynamic
operational simulation model; community-level models of major seagrass community
structure and function; population-level model of sponge components of the
hardbottom community; landscape level mangrove model for Biscayne Bay; trophodynamic
models of the major fish and invertebrate species of the Biscayne Bay-coral
reef coupled ecosystem; conceptual model of the societal components, drivers,
and stressors of the South Florida regional environment; and a Florida Keys
coral reef tract conceptual model.
Other research activities in Florida Bay have resulted in models and tools
valuable to the restoration process and to resource managers in the region.
This includes data and models of Florida Bay oceanographic and atmospheric
conditions that estimate and predict oceanic flow into the Bay, south Florida
rainfall amounts and distribution, freshwater Everglades flow into the Bay
through the Shark River Slough, mercury accumulation, nutrient cycling, and
consequent impacts on Bay living resources. These results are helping researchers
and resource managers assess how anthropogenic and long-term natural fluctuations
contribute to the current ecological problems in Florida Bay.
MANAGEMENT AND POLICY IMPLICATIONS
The impacts on coastal Florida of land-based restoration activities in the
Everglades are direct but may not be immediate. Similarly, newly initiated
HAB studies will require some time before bloom impact controls can be designed.
Achieving a predictive capability to better manage South Florida marine resources
and assist South Florida restoration planning is the main goal of COP's research
activities. Attaining a predictive capability implies better understanding
of the physics and ecology of south Florida coastal ecosystem and its relationship
to surrounding marine, terrestrial and atmospheric systems with which it is
intimately connected.
Over the past several years, there has been a decline in the abundance of
live coral in the Florida Keys National Marine Sanctuary (FKNMS), and shifting
patterns of relative abundance of seagrass species in Florida Bay. Management
issues concerning hardbottom communities could not be addressed because of
a lack of ecological research. Current COP research intends to determine the
causes of coral decline with emphasis on cause and effect; possible associations
between water quality and seagrass distribution; and the functional significance
of hardbottom communities in the FKNMS ecosystem. The fully protected zones
of the FKNMS, including the Tortugas Ecological Reserve, were created to assist
in the protection of biological diversity and to disperse resource utilization
in order to reduce user conflicts and to lessen the concentrated impact to
marine organisms on heavily used reefs. Research will soon be underway to
monitor commercially important species (e.g., spiny lobster) and key depleted
fishery species (e.g., queen conch), as well as to create ecosystem models
of reef fish communities to predict the effects of zoning on species diversity,
abundance, and trophic structure.
Related Websites
For
more information, contact:
Larry Pugh
CSCOR/Coastal
Ocean Program
phone: 301-713-3338
e-mail: coastalocean@noaa.gov
Last Updated:
April 22, 2003
