Growing season ecophysiology of Taxodium distichum (L.) Rich. (bald cypress) saplings in a restored wetland: a baseline for restoration practice

Wetland restoration is a common practice in the southeastern United States, where changing land use patterns have resulted in the widespread degradation of coastal ecosystems. Re-establishment of indigenous vegetation is a fundamental paradigm of restoration practice. In freshwater wetlands, this often includes planting flood-tolerant species such as Taxodium distichum (L.) Rich (bald cypress). While much is known regarding the ecology of this foundational species, research establishing the ecophysiological profile of mature bald cypress under stress-free, baseline conditions is limited. Therefore, a study was undertaken in 2015 to monitor the growing season ecophysiology of a bald cypress stand in a restored coastal wetland. Net photosynthesis was constant in the early to mid-growing season, declining steadily late in the growth season until the visible onset of needle senescence. Patterns in transpiration matched those observed for photosynthesis, whereas needle conductance and chlorophyll fluorescence appeared to track expected patterns associated with needle development. Trees at this site appeared healthy and were reproductively competent. However, long-term monitoring of the stand would help evaluate the ecological sustainability of this restoration project. We advocate for the inclusion of ecophysiological-based vegetation monitoring within restoration projects, enabling a sensitive and early indication of the trajectory of a restoration plan.