【Title】Composition, Structure and Regeneration Dynamics of Olea ferruginea Royle Forests from Hindukush Range of Pakistan
【Author】NASRULLAH Khan1 ; FAYAZ Ali1 ; KISHWAR Ali2; SHAHID Shaukat3
【Addresses】1 Laboratory of Plant Ecology Department of Botany University of Malakand, Chakdara Dir Lower Khyber Pakhtunkhwa 25000, Pakistan; 2 Department of Plant Sciences, School of Biological Sciences, University of Reading, RG6 6AS, the United Kingdom; 3 Institute of Environmental Studies, University of Karachi, Gulshan -e-Iqbal 75300, Karachi, Pakistan
【Citation】Nasrullah K, Fayaz A, Kishwar A, et al. (2015) Composition, structure and regeneration dynamics of Olea ferruginea Royle forests from Hindukush range of Pakistan. Journal of Mountain Science 12(3). DOI: 10.1007/s11629-013-2831-1
【Abstract】The abundance of Olea ferruginea in Malakand Division has been significantly reduced across its distribution range due to anthropogenic pressure in the recent past. A number of initiatives were taken for grafting this species to obtain better seeds for oil production, without the basic information on their ecology and management. To address this knowledge gap, we quantified the composition, structure and regeneration dynamics of Olea ferruginea forests in Malakand Division, Hindukush range of Pakistan. In the present study, five communities dominated by Olea ferruginea were identified using Ward’s agglomerative cluster analysis. Total tree density ranged from 153-2602 plants/ha, and basal area from 19.55 to 2353 m2 ha-1 with Olea having a relative density of 51% to 87% and basal area of 48% to 93%, respectively. The density of juveniles of the dominant and subordinate tree species were generally low which reflect their narrow distribution in the study area. Size-class distributions of O.ferruginea disclosed a bell-shaped pattern, indicating that forests were heavily exploited by local inhabitants in previous periods and recently by armed forces owing to security risks in the study area. The age (mean max. 300±34 years) and annual increment (3.2±1.2 years/cm) indicates that the species is long lived and generally slow growing among the different broad leaved species studied so far. However, the oldest trees can be found by the exploration of large diameter trees in the area. In addition, we found a stable linear relationship between the age and diameter (r2 = 0.779),indicating that diameter is a good predictor of age for this broad leaved species. In view of its relatively slow growth, longevity and positive ring-width characteristics O.ferruginea seems to be a suitable choice for dendroecological and dendrochronological studies in lesser Himalayan and Hindukush ranges of Pakistan. The results obtained from this study may help in understanding the composition, structure and regeneration dynamics of other subtropical broad leaved species.
【Keywords】Olea ferruginea; Species composition; Ward’s agglomerative cluster analysis; Seedling; Dendroecology