ecological characterization atlas of coastal alabama - Data Center

SOCIOECONOMICS
INTRODUCTION
The socioeconomic elements mapped and discussed include man-made features
and natural areas having either ecological or economic significance, such as
wildlife refuges, State park recreational areas, barrier islands, and
historical or archaeological sites . Man-made features include solid waste
landfills, navigation channels, and dredge-spoil disposal areas . Many of
these areas are subj ect to Federal , state, or 1 ocal regul ations for l and use
within their boundaries .
LAND USE AND LAND COVER
Four categories of land use are mapped on the atlas sheets : forested,
urban, agricultural, and uncategorized . Forested land was considered as any
area with greater than 30% canopy cover . Forest land may be used for timber
production, as a game refuge, or any other use which does not alter the woodland
nature . Some mature old fields which have reverted to woodland are included
in the forested category .
The urban category includes residential, commercial, and industrial land
uses and includes major transportation facilities such as large highway interchanges
and airports . The agricultural category includes areas currently
under cultivation or prepared for cultivation, pasture, and associated
buildings . It does not include timber plantations .
The uncategorized classification is essentially a residual category . A
cross check with the Biological Resources maps in this atlas will show,
however, that more than 90% of this category is wetland, as defined by the
U .S . Fish and Wildlife Service (Cowardin et al . 1979) .
All categories mapped were derived by aerial photo interpretation . The
photos were taken by the National Aeronautics and Space Administration (NASA)
and were color infrared at a scale of 1 :62,500, dated 1979 . The minimum
mapped unit is approximately 10 acres . Mobile and Baldwin counties were
mapped in 1972 by the U .S . Geological Survey using criteria developed by
Anderson et al . (1976) . Very general land use maps have also been produced
by local or regional Alabama agencies .
The following information on the two coastal counties is included to
convey a general understanding of land cover and use in the area . The data
are from a wide variety of sources as reported in the U .S . Fish and Wildlife
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