ecological characterization atlas of coastal alabama - Data Center

oad flood plains of the Mobile/Alabama/Tensaw Rivers (Mobile quadrangle)
and the Grand Bay Swamp (Biloxi quadrangle) . The land here is level,
frequently flooded, swampy bottomland with meandering streams and sloughs and
a very high water table . These areas are mainly used as wetland wildlife
habitat and woodlands . The organic Dorovan soils are found in the wetter,
l ower areas of the fl ood pl ai n and compri se grayi sh-brown to bl ac k mucky peat
overlying mottled dark• grayish-brown to mottled gray subsoil . Levy soils are
dark-gray silty loam overlying dark-gray silty clay subsoils on higher ground
than Dorovan soils and are adjacent to natural levees along streams . The
Iuka soils are dark-brown fine sandy loam overlying dark yellowish-brown fine
sandy loam subsoils with mottles of grayish-brown and interpersed with loamy
sand and loam . The Johnston soils are also found at higher elevations than
the Dorovan soils, in flat areas adjacent to uplands . Their surface is thick
black mucky loam overlying gray loamy fine sand and fine sandy loam layers .
The Urbo soils have a dark grayish-brown silty clay loam topsoil underlain by
grayish-brown silty clay subsoil . They are found in level to gently sloping
flood plains draining coastal plains and prairie areas .
The Annemaine-Wahee-Leaf association (2) is found on the terraces
bordering the Mobile/Alabama/Tensaw Delta in Baldwin County, whereas the
terraces along the delta (and along the Escatawpa River) in Mobile County are
of Izagora-Bethera-Suffolk association (13) soils . These areas are fairly
wet woodlands, with little agric ulture, and are sparsely populated . The
lower lying areas of the Annemaine-Wahee-Leaf association are comprised of
Leaf soils, which have dark grayish-brown silt loam over a subsoil of mottled
gray silty clay . The Annemaine soils are moderately well-drained, deep soils
with a brown fine sandy loam surface layer, a subsoil of yellowish-red clay,
and a mottled loamy substratum . The Wahee soils are not as well drained as
the Annemaine, and they differ in having a surface layer of dark
grayish-brown sandy loam overlying a mottled yellowish-gray sandy clay or
sandy clay loam subsoil .
The Izagora-Bethera-Suffolk association (13) soils were formed in loamy
and clayey marine and alluvial sediments on terraces . Izagora and Suffolk
soils have loamy subsoils, whereas Bethera soils overlie clayey subsoils .
Izagora series soils have a dark brown fine sandy loam surface while Suffolk
series soils have dark brown loamy sand surface . Bethera series soils have
dark gray loam surface layers, and are located in depressions and drainage
ways . The more sloping areas adjacent to natural drainage ways contain
Suffolk soils, and above them are the Izagora soils on the gently sloping
side slopes and broad flat areas . These areas are mostly woodland, although
there is some agricultural potential . As this area is wet and flood prone,
it is poor for urban uses .
The major component of the Coastal Lowlands, exclusive of the alluvial
and deltaic plains, is the coastal beach area . This area is composed of
white and yellow sand deposits of Recent age, with elevations ranging from
sea level to around 7 m (20 ft) . In Baldwin County, the coastal beach areas
are usually associated with the Fripp-Leon soil association (9) . The Coastal
Lowlands in Mobile County include the Bayou-Escambia-Harleston association
(15) along the coastal terraces in the southern portion of the county, and
the Urban Land-Smithton-Bennedale association (16) in the city of Mobile .
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