Baldwin County Wetland Conservation Plan - Alabama Department ...

Baldwin County Wetland Conservation Plan Final Summary Document
Rationale: Floodwater storage capacity is greatest with alternating wet and dry
conditions as found in the regimes listed above. Wetlands that are permanently flooded
have little additional capacity to store water during flood events; while those that flood
less often than seasonally play a lesser role than others in storing floodwaters. Thus,
those that exhibit the above NWI water regimes are considered to function at a higher
level than those that have different regimes. This variable was identified remotely
through digital NWI maps.
Data Column: wat_reg; 1 point
Question 6: Does the adjacent land use surrounding the observed wetland fall into one of the
following land use categories; residential, commercial, industrial, transportation or
mixed urban use?
Rationale: These land use categories are marked by the presence of impervious
surfaces which will increase the volume of surface water sheetflow entering the wetland.
Thus, a wetland surrounded by these land uses will be more likely to receive and store
larger volumes of water. This variable was identified remotely through digital land use
data provide by the Federal Emergency Management Agency (FEMA).
Data Column: WS_LULC; 1 point
Sediment/Toxicant/Nutrient Removal and Soil Stabilization
Question 1: Does the observed wetland contain rooted vegetation or coarse woody debris as
indicated by one of the following NWI class designations: FO, SS or EM?
Rationale: Rooted vegetation and coarse woody debris provide frictional resistance for
water flow thus slowing water as it moves through the wetland. This water velocity
reduction allows sediments to settle out of the water column thus resulting in improved
water quality. For nutrient cycling to occur, both living and dead biomass must be
present. The presence of coarse woody debris indicates a level of decomposition which
will ultimately release nutrients into the soil which can then be assimilated into living
material through plant uptake. Although the presence of coarse woody debris cannot be
measured directly through remote techniques, it was determined indirectly. In a natural
riverine ecosystem there is both living and dead material. Thus, if a site contains rooted
live vegetation (which was measured remotely through NWI) it follows that the site would
also contain dead material (in some form). Thus the presence of rooted vegetation is
indicative of nutrient cycling occurring on the site which indicates a high level of function
for this variable.
Data Column: root_veg; 1 point
Question 2: Is the water regime of the observed wetland either intermittently exposed (G),
semi- permanently flooded (F), seasonally flooded (C), or temporarily flooded (A)?
Rationale: If the wetland exhibits one of the above water regimes, it is likely to provide
the alternating wet and dry conditions necessary to promote the microbial activity, found
in anaerobic conditions, which aid in nutrient processing. This variable was identified
remotely through digital NWI data.
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