understory cover and sunlight transmittance. The median dbh was not
 greater for trees not hosting vines versus those hosting vines (Mann-
 Whitney test at the 95% confidence level). In fact, vines may play an
 important role in contributing organic matter and cycling nutrients
 throughout ecological succession.

 3. As ecosystems develop, do vines persist? Do vines exhibit successional
 trends where different species are dominant during different stages of
 succession? The number of rooted vines and dry weight vine biomass
 increased with increasing site age, suggesting that vines exist in mature
 forested wetland systems at some level. Only herbaceous vines occurred
 during the first few years after site establishment, followed by the
 recruitment and establishment of woody vines. As systems developed
 vine species richness increased, with the 0.5, 2, and 5-year-old sites
 having vine species richness values of zero and the 18-year-old site with a
 value of 3.8. Frequency of occurrence increased with site age, with the
 0.5 and 2-year-old sites having 0% vine occurrence while the 18-year-old
 site had 100% frequency of occurrence.

 4. Are there specific environmental conditions that favor vine dominance?
 There appears to be a zone of favorable edaphic conditions where vines
 thrive. The most notable condition was intermediate soil moisture,
 ranging from 5-40%. This zone appears as a band between the upland
 ecotone region and the more saturated soils of the open water region.
 NH4-N (rS = 0.412, P = 0.006) appears to correlate the greatest with
 rooted vines, with the remaining plant-available nutrients Ca, Mg, K, P, Fe
 and N03-N not demonstrating significant correlations.


THE OCCURRENCE OF VINES

 Vines within the central Florida phosphate district appear to represent less than
1% of the estimated total above ground biomass/m2 when compared to data available
from several wetlands in the southeastern United States (Appendix 6.F). Vines were
found on all of the sites sampled throughout the constructed forested wetlands of the
central Florida phosphate district. Even the youngest site, 0.5-year-old LP2 Phase 1,
hosted vines, although they did not occur within the randomly placed sample transects
(Table 6.4). The oldest site, 18-year-old Sink Branch, had the greatest heterogeneity with
12 different genera of vines recorded. All of the sites sampled had varying site histories
including differences in hydrology, soils, and species planted, yet all of the sites provided
adequate conditions for vine growth. In fact, most of the vines identified occurred on
multiple sites (Figure 6.8), suggesting that site history may play a limited role in
determining the occurrence of vines throughout the reclaimed landscape.

 Through the first 18 years of reclaimed wetland development, the occurrence and
variety of vines increased. Throughout succession vines appear to play an important role


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