XVI International Botanical Congess

Mangrove diversity and structure are driven by key processes of growth development and regeneration. Forest development progresses through colonisation, early development, maturity, to senescence. Regeneration involves repair of forest canopy. The structure of a stand is often taken to be indicative of stand age, but such observations do not account for regenerative factors. The most notable are creation of light gaps and large-scale disturbance. Light gaps are common in closed forests, but their role in mangrove s appear under-estimated. Recent treatments and new observations of Rhizophora forests in Panama and Australia are the basis for revising current understandings of factors driving turnover. A combined model is proposed, incorporating a development model with reproductive and vegetative regenerative cycles. Based on this framework, diversity and structure of particular mangrove stands can be explained. The combined model also shows how determination of stand age based on forest structure is untenable. Regenerative cycles apparently play an important role, if not the chief role, in shaping mangrove forest diversity and structure. The amount of influence brought to bear, as might be guessed, depends on frequency, severity and extent of gap creation.