Forests are highly susceptible to dieback under ongoing climate warming. In degraded forests, dead standing trees, or snags, have become such prominent features that they should be taken into account when setting management interventions. This study investigated (1) the extent and spatial pattern of standing dead stems of Juniperus procera and Olea europaea subspcuspidata along an elevational gradient, and (2) the effect of dieback on forest stand structure. We quanti!ed abundance, size, and spatial pattern of tree dieback in 57 plots (50 m ! 50 m) established at 100 m intervals along !ve transects. The snag density and basal area (mean " SE) of the two species combined were 147 " 23 stems ha#1 and 5.35 " 0.81 m2 ha#1, respectively. The percentages of snags were extremely high for both J. procera (57 " 7%) and O. europaea subspcuspidata (60 " 5%), but showed a decreasing trend with increasing elevation suggesting that restoration is even more urgent at the lower elevations. Snags of the two species accounted for 31 and 45% of total stand density and basal area, respectively. Living stems exhibited truncated inverse-J-shaped diameter and height class distributions, indicating serious regeneration problems of these foundation species in the study area. In addition to direct interventions to assist recruitment of climax tree species, sites with high dieback would probably bene!t from snag reduction to prevent !re incidents in the remaining dry Afromontane forests in northern Ethiopia.
DOI:
https://doi.org/10.1016/j.jaridenv.2010.12.013Altmetric score:
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Publication year
2011
Authors
Aynekulu B E; Denich M; Tsegaye D; Aerts, R.; Neuwirth B; Boehmer H J
Language
English
Keywords
climate change, ethiopia, forestry, forests, global warming, juniperus, olea europaea, semiarid climate
Geographic
Ethiopia
