METHODS


 Data on the occurrence of vines and physical and biological conditions under
 which they grow were collected from constructed wetland ecosystems in the central
 Florida phosphate district. Field data collection was organized into two parts. First, a
 chronological sequence (chronosequence) of nine sites was studied, recording differences
 in physical and biological conditions to relate to the site dominance of vines. Second,
 intensive sampling of sites where vines were dominant and adjacent areas without vine
 dominance was conducted, measuring the same parameters. In the sections that follow,
 the first is "Description of Study Sites" including conditions at site establishment when
 available. The next two parts are organized under the main headings of "Chronosequence
 Sampling Design" and "Intensive Sampling Design" reflecting the two parts of the field
 data collection. The fourth section with the heading, "Data Analysis" gives details of the
 methods used to analyze collected field data. The fifth section, "Simulation Modeling"
 provides the methodological approach to computer simulation of a successional model
 that includes vines.


 DESCRIPTION OF STUDY SITES

 Figure 6.2 shows the location of each study site, and Table 6.1 provides a
 summary of the study sites described below.

 Cargill LP2-Phase 1 (referred to as LP2-Phase 1) is located at the Fort Meade
Mine. It is a fringing forested wetland, with no standing water (0 cm water depth) at the
time sampled. Sand tailings were the primary soil substrate covered with mulch/muck. It
had not been treated for the control of nuisance species. The area sampled was planted in
early 1998 with several tree species; however, a species list was not available. Sampling
occurred in August of the first growing season in 1998.

 IMC-Agrico FGGSB2 (referred to as Super Hummock) is a 15.6-hectare
depressional wetland bordering a tributary of the Alafia River. It is located at the Fort
Green Mine. During construction, large hummocks were created with muck, and
sampling occurred randomly both on and off of the hummocks. The wetland
depressional areas are comprised of sand tailings, with a mulched layer on top. Water
depth at sampling ranged from 0-3 cm. The site was herbicided to control Ludwigia
peruviana (L.) Hara. (primrose-willow) after sampling in 1998. Canopy species planted
include Acer rubrum L. (red maple), Carya aquatica (Michx. F.) Nutt. (water hickory),
Catalpa bignoides Walt. (cigar-tree), Fraxinus caroliniana Mill. (pop ash), Gordonia
lasianthus (L.) Ellis. (loblolly bay), Liquidambar styraciflua L. (sweet gum), Magnolia
grandiflora L. (southern magnolia), Magnolia virginiana L. (sweetbay), Nyssa sylvatica
Marsh. (black gum), and Taxodium distichum (L.) Rich. (baldcypress). Cephalanthus
occidentalis L. (common buttonbush) was the only shrub planted, and no herbaceous
species were planted.


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