CONCLUSIONS


 It is relatively easy to deem a constructed wetland unsuccessful if it doesn't
maintain an appropriate density of the trees originally planted. But, tree survival and
density of mature trees, although necessary for success, do not necessarily reflect future
success or indicate a self-sustaining ecosystem. In fact, documenting successful seed
production of trees alone is not in itself an adequate indicator of success. Many plant
species exhibit increased sexual and asexual reproduction under conditions of stress,
presumably a means for dispersing offspring into a less stressful environment. Both seed
production by mature individuals and establishment of offspring must be documented and
provide a better indication of sustainability than seed production alone. Diameter at
breast height, frequency distributions of tree size classes and community basal area
provide these measures because they reflect tree growth and recruitment.

 Wetland ecosystems organize around their driving energies. There is an energy
signature associated with forested wetlands, which includes hydrological energies
associated with depth, duration and frequency of-flooding, light energy and energies
associated with soil parameters. The appropriate combination of these driving energies
results in a functioning forested wetland. Typically, assessment of wetland health or
restoration success focuses on the biotic component of a wetland rather than the abiotic
driving energies that give rise to conditions that foster forested wetlands. This is done
presumably because the biotic component of an ecosystem integrates the driving
energies, and therefore, is an adequate indicator of the presence of appropriate driving
energies and ecosystem functions.

 In addition to the emphasis on the biotic component of wetland ecosystems,
previous efforts at assessing the success of constructed wetlands have focused on the
directional change of individual components of the ecosystem, rather than emerging
properties, which integrate even further the driving energies and ecosystem functions into
easily measurable parameters.

 Several easily calculated soil parameters show promise in establishing trajectories
for assessment. If appropriate hydrology and vegetation have been restored, organic
matter should increase, and bulk density should decrease over time. Increasing the
number of sites sampled will determine the applicability of this method.


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