A model of seasonal foliage dynamics of the subtropical mangrove species Rhizophora stylosa Griff. growing at the northern limit of its distribution

  Background   Progress of forest production in response to the environment requires a quantitative understandingof leaf area development. Therefore, it is necessary to investigate the dynamics of seasonal crown foliage in orderto understand the productivity of mangroves, which play an important role in the subtropical and tropicalcoastlines of the world.

  Methods   Crown foliage dynamics of the mangrove Rhizophora stylosa were studies to reveal patterns of leafrecruitment, survival and seasonal leaf area growth.

  Results   Flushing of leaves occurred throughout the year, but both flushing and leaf area growth pattern of leavesvaried with season. Maximum flushing occurred in summer, but leaf areas did not differ significantly with season.The half-expansion period is longer, and the intrinsic rate of increase was lower in winter. Summer flushed leavesgrew faster at their initial stage and reached their maximum area over a shorter period of time. The difference intemperature and air vapor pressure deficit (VPD) between summer and winter contributed to the present dynamicsof foliage patterns. The mean leaf longevity was estimated to be 13.1 month. The crown foliage area was almoststable throughout the year.

  Conclusion   Homeostatic control of the crown foliage area may be accompanied by the existence ofecophysiological mechanisms in R. stylosa. Integrating crown foliage dynamics into forest models represents animportant step towards incorporating physiological mechanisms into the models for predicting growth responsesto environmental changes and for understanding the complex responses of tree growth and litter production.