**STUDY TITLE**: Northeastern Gulf of Mexico Coastal Ecological
Characterization.

**REPORT TITLE**: Alabama Coastal Region Ecological Characterization. 
Vol. 1, Coastal Bibliography; Vol. 2, A Synthesis of Environmental Data.

**CONTRACT NUMBER(S)**: BLM: MU0‑20; MMS: 14‑12‑0001‑30037.

**SPONSORING OCS REGION**: Gulf of Mexico.

**APPLICABLE PLANNING AREA(S)**: Eastern Gulf of Mexico; Central Gulf of
Mexico. 

**FISCAL YEAR(S) OF PROJECT FUNDING**: 1980; 1981; 1982; 1983.

**COMPLETION DATE OF REPORT**: June 1982.

**COST(S)**: FY 1980: \$360,000; FY 1981: \$250,000; FY 1982: \$375,000;
FY 1983: \$200,000.

**CUMULATIVE PROJECT COST**: \$1,185,000.

**PROJECT MANAGER(S)**: K. Adams.

**AFFILIATION**:  U.S. Fish and Wildlife Service.

**ADDRESS**: 1010 Gause Boulevard, Slidell, Louisiana 70458.

**PRINCIPAL INVESTIGATOR(S)\***: L. Acker, E. McCullough, M. Mettee, P.
O\'Neil, D. Wilson.

**KEY WORDS**: Eastern Gulf; Central Gulf; Alabama; baseline; biology;
characterization; synthesis; bibliography; literature review; coastal
zone; terrestrial; geology; physiography; plankton; birds; commercial
fishing; endangered species; literature review; synthesis.

**BACKGROUND**: Coastal Alabama and adjacent waters are an important
industrial, recreational, and seafood production area in the northern
Gulf of Mexico.  Discovery of oil and gas in and around Mobile Bay,
development of State‑owned and outer continental shelf fossil fuel
reserves, and completion of the Tennessee‑ Tombigbee Waterway have
enhanced the area and should promote continued urban and industrial
expansion.  Recognizing the highly productive area along the Alabama
coast and the resource planning to maintain these areas, the U.S. Fish
and Wildlife Service initiated the Ecological Characterization Program
for selected coastal areas.

**OBJECTIVES**: (1) To summarize all available information on natural
resources of coastal Alabama.

**DESCRIPTION**: Coastal Alabama lies within the Coastal Plain province
and the Mississippi‑Alabama shelf section of the Continental Shelf
province.  Part of the study was a literature search and bibliography
pertaining to coastal Alabama.  The report characterizes the area with
respect to geology, hydrology, climate, plant life, animal life,
endangered and threatened species, and an area‑wide conceptual model. 
The aim of the conceptual representation is for the information
synthesis to present the coastal water environment as integrated systems
of physical, chemical, and biological forces.  These representations
were developed to serve as a reference source of known information about
coastal Alabama.

**SIGNIFICANT CONCLUSIONS**: The holistic conceptual model of coastal
Alabama as a single energy system was comprised of two basic units.  One
unit consisted of four natural ecosystems and their connective
pathways.  The second unit consisted of manipulated subunits such as
agricultural ecosystems and urban/industrial systems that require
extensive inputs of external energy.  The conceptual model provides a
workable hierarchical system that indicates the interrelationships that
exist between natural and modified systems.  Although some areas need
further research, the conceptual model may be used as a management tool
for maintaining the balance between individual subunits within the
system.

**STUDY RESULTS**: Coastal Alabama has four physiographic subdivisions. 
The southern pine hills comprise the elevated east and west lateral
portion of coastal Alabama.  The alluvial plain, deltaic plain, and
coastal lowlands are relatively flat, are adjacent to Mississippi Sound,
and extend along margins of Mobile, Bon Secour, and Perdido Bays.  These
flat physiographic subdivisions also extend northward along the
Tombigbee and Alabama Rivers.  The coastal boundaries of these
relatively shallow bays are defined by various barrier islands and
spits.  The Mississippi‑Alabama shelf is a triangular area seaward of
the barrier islands and extends from the Mississippi River Delta to the
De Soto Canyon.

Coastal and offshore Alabama are underlain by sediments ranging from
pre‑Jurassic to Holocene.  These rock units are possibly more than
7,620 m (25,000 ft) thick at the coast and decrease southward by 1.9 to
9.4 m/km (10‑50 ft/mi).  The coastal and continental shelf topography
and sedimentation result from tidal and current movements, as well as
alluvial and deltaic progradation and destruction.

The prominent structural geological features along coastal Alabama are
the peripheral faults, Mobile graben, the Citronelle domal anticline,
and the Wiggins uplift.  Tectonic hazards are not a problem in coastal
Alabama because there are no known active faults.

Oil and gas production is well established in coastal Alabama with
developed fields at Citronelle, Chunchula, Hatter\'s Pond, and South
Carlton.  There is a high potential for future gas and oil production.

Coastal Alabama has a dynamic hydrologic system with the focal point of
the system being Mobile River and Mobile Bay into which it flows. 
Average yearly (freshwater) discharge from this system into the Gulf of
Mexico is 50 km^3^ (12 mi^3^).  Flooding is the worst natural hazard of
coastal Alabama and may result from storm surges and heavy rainfall
associated with hurricanes and other tropical storms.  Flood discharge
has a pronounced effect on inland and estuarine water salinity and
coastal sedimentation.  Climatic and physical oceanographic factors
along coastal Alabama are well understood and recorded because of the
extent to which they affect this particular area.

Specific studies of coastal Alabama phytoplankton were lacking, however,
an intensive study of Mobile Bay phytoplankton has been undertaken. 
Community diversity and species composition of aquatic vegetation has
declined.  Habitat types were described and characterized by associated
flora.  Animal diversity was high in coastal Alabama where the fauna
included terrestrial, freshwater, saltwater, and brackish water species
characteristic of temperate and subtropical climates.  Coastal Alabama
has important habitats for many commercially valuable biota (i.e.,
shrimp, oysters, and fish).  This area maintains a highly diversified
avifauna (greater than 300 species) which is attributed to the multiple
habitats present in coastal Alabama.  Fifty‑seven mammalian species have
been reported from coastal Alabama.  Some flora and fauna are considered
endangered or threatened.

The natural ecosystems are functionally composed of producers,
consumers, and decomposers.  Energy within the system is transferred and
transformed between trophic levels.  This system is considered
self‑sustaining.  The agricultural, urban/industrial, and associated
pathways rely heavily on external energy from other systems illustrating
their independence on natural ecosystems.

**STUDY PRODUCT(S)**: O\'Neil, P. E., M. F. Mettee, E. J. McCullough, L.
A. Acker, and D. W. Wilson.  1982.  Alabama Coastal Region Ecological
Characterization.  Vol.  1, Coastal Bibliography.  A final report by the
U.S. Fish and Wildlife Service for the U.S. Department of the Interior,
Minerals Management Service Gulf of Mexico OCS Office, Metairie, LA. 
NTIS No. PB83‑180661.  FWS/OBS‑82/21.  Contract No. 14‑12‑0001‑30037. 
408 pp.

O\'Neil, P. E. and M. F. Mettee.  1982.  Alabama Coastal Region
Ecological Characterization.  Vol. 2, A Synthesis of Environmental
Data.  A final report by the U.S. Fish and Wildlife Service for the U.S.
Department of the Interior, Minerals Management Service Gulf of Mexico
OCS Office, Metairie, LA.  NTIS No. PB83‑190009. FWS/OBS‑82/42. Contract
No. 14‑12‑0001‑30037. 346 pp.

**\*P.I.\'s affiliation may be different than that listed for Project
Manager(s).**