Flowering phenology of Campanula on Mt Olympos, Greece
(EN)
Blionis, G. J.
(EN)
Πανεπιστήμιο Ιωαννίνων. Σχολή Επιστημών και Τεχνολογιών. Τμήμα Βιολογικών Εφαρμογών και Τεχνολογιών
(EL)
Blionis, G. J.
(EN)
We studied the flowering phenology of the genus Campanula (represented by nine species) along the elevation gradient of Mt Olympos (Greece) in order to assess whether there are elevation patterns at the genus level and whether these relate to patterns previously observed along such gradients at the community level. The traits examined were time and duration of the flowering period, flower life span, and duration of male and female flower phases. Floral attributes, such as number of flowers per plant, flower biomass, flower size, were also studied in order to examine whether they change with elevation or influence flower phenology. Flowering of Campanula species started in mid-May and ended in late September. The average duration of flowering of the genus was ca 27 d and the average floral longevity 4 d. In all but one species, the female phase lasted longer than the male. Campanula versicolor differed remarkably from all others in flower phenology and other floral traits. Nearly all Campanula populations studied had right or positively skewed flowering distributions indicating that flowering begins more abruptly than it ends. At the genus level, the time of flowering increased with elevation by 2-3 d for every 100 m. Floral longevity also increased with elevation, by 0.2 d for every 100 m. Neither duration of flowering nor duration of the flower phases showed any consistent change with elevation. The same is true of the non-phenological floral traits examined. No trade-off between duration of flowering and flower life span or between structure and maintenance of flowers was apparent. The pattern of increasing floral longevity along the elevation gradient suggests a mechanism of compensation for reduced pollinator availability.
(EN)
