10000 Ca 10000 6Ca
 MMg lMg
 M K M K
 1000- p 1000 Op
 Fe I MFe
 100 -o 100


 10 10


 1 1
 Sink Branch Parcel B

 Figure 7.28 (Cont.) Available Soil Nutrient Signatures for Constructed Forested
 Wetlands.


 Canopy Trajectories

 Canopy tree species richness shows no trend over time. Species richness within
constructed forested wetlands is primarily a function of the number of species planted
during reclamation. The greatest species richness was found in the two oldest and the
two youngest sites. Parcel B (19 years) was an experimental project that incorporated the
planting of floodplain tree species not normally found in central Florida, as well as others
more commonly found in the area. This resulted in unusually high species richness. Sink
Branch (17 years) had a broader range of habitats within the site, ranging from mesic to
wet. This provided areas for upland species not normally found in a wetland to establish,
resulting in greater species richness. The species richness of the younger sites results
from a greater number of species being planted during reclamation. Therefore, increases
in canopy species richness in constructed wetlands do not necessarily reflect wetland
success but are simply a result of human interactions with the wetland.

 Frequency of occurrence of tree seedlings and saplings shows a very weak
positive trend with age. Occurrence of saplings was probably more closely related to
distance from unmined forested areas, which would provide a seed source. The
demonstration of tree reproduction and seedling establishment is important in assessing
the success of wetland reclamation. With increases in sample size including sites of
various ages and distances from seed source, the time necessary for seedling
establishment for both isolated constructed wetlands deprived of a seed source and those
adjacent to seed sources may be determined. The data collected suggest that very young
sites (2 years) are capable of supporting establishment of wind dispersed seeds such as
Acer sp. Perhaps the best way.to determine if constructed forested wetlands are capable
of recruitment, and which species have a greater likelihood of being recruited, could best


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