Canopy Gap Regeneration And Dynamics In The Afromontane Forest Of Bale Mountains

Change in forest communities and recruitment of new individuals into tree populations depend on the dynamics andrnformation of canopy gaps. Gap dynamics and canopy gap regeneration were investigated in Harena Forest of BalernMountains, Southeastern Ethiopia at altitudes ranging from 3000 – 2000 m a.s.l. Wind was found to be the mainrntype of natural disturbance resulting in the overthrow and snapping of heavily crowned emergent canopy trees. Thernmost affected canopy species by this disturbance regime was Dombeya torrida. 14 species were found to be gaprnmakers. The mean DBH of the gap makers was 50.4cm. Mean gap size of the forest was (289.74+165.48 m2) andrnalmost all the gaps were found in sloppy areas. Twenty-four different woody species were encountered as gap–fillerrnspecies along different altitudes. Of these species, six were recruited only in gap sites while the gap environmentrnfavored most of the rest. Seedling and sapling density of the gaps were higher than that of closed canopied sitesrnindicating the importance of gaps for maintaining woody species diversity in the forest. The strong negativerncorrelation between slope, altitude, and species and seedling densities indicates that both factors affect gaprnregeneration. Otherwise, gap size differentiation in the forest and replacement probabilities in the Harena forest wasrnweak (less than 0.5) except for Diospyros abyssinica(0.86); most of the gap makers were replaced by other subcanopyrnspecies of the forest. Thus, species recruitments in gaps of the forest are likely due to chance effects.rnGermination trial of the soil seed banks of Harena forest collected from the sampled gaps and canopied sites hasrnrevealed a high dominance of herbaceous species. Only five of the 24-gap filling species and three of the gap makerrnspecies were recovered in the soil seed bank of the gap sites and even that was in smaller density. Thus, the chancernof getting an immediate replacement of the canopy trees, if removed naturally, was found to be minimal.rnKey words: Canopy regeneration, Disturbance, Gap regeneration, Gap makers, Gap fillerrnspecies, Replacement probabilities, soil seed Bank.

Get Full Work

Report copyright infringement or plagiarism