Regeneration of Abies pinsapo within gaps created by Heterobasidion annosum-induced tree mortality in southern Spain
iForest : Biogeosciences and Forestry
© iForest -Biogeosciences and Forestry © SISEF http://www.sisef.it/iforest/ 209 iForest (2014) 7: 209-215 Citation: Navarro-Cerrillo RM, Camarero JJ, Manzanedo RD, Sánchez-Cuesta R, Lopez Quintanilla J, Sánchez Salguero R, 2014. Regeneration of Abies pinsapo within gaps created by Heterobasidion annosum-induced tree mortality in southern Spain. iForest 7: 209-215 [online 2014-02-27] We explored the effects of tree-fall gaps caused by Heterobasidion annosum-induced tree death on the regeneration
... on the regeneration of the relict Abies pinsapo in southern Spain. We analyzed the structure and regeneration of A. pinsapo in 44 circular closed-canopy plots and 11 gaps (mean size 75 m 2 ) located in H. annosum infection foci. We measured adult density, basal area, and height of all tree species with a diameter at breast height greater than 7.5 cm and quantified regeneration abundance. Diameter structures were analyzed using Weibull functions. A. pinsapo comprised 49-81% of total adult tree density (358-1418 trees ha -1 ) and total basal area (15.70-39.22 m 2 ha -1 ). Density of A. pinsapo juveniles ranged from 129 to 416 individuals ha -1 , while that of juveniles of other tree species such as Quercus ilex was much lower. A. pinsapo saplings and seedlings were more abundant within gaps than in closed-canopy sites. A. pinsapo regeneration was related to the tree species composition of the stands adjacent to gaps. The main potential species replacing A. pinsapo in H. annosum-induced gaps were, in decreasing order of importance, Quercus ilex, Q. faginea, and Juniperus oxycedrus. The current stand structure and gap-infilling processes suggest that A. pinsapo regenerates adequately within H. annosum-induced gaps. However, the relative proportion of other coexisting tree species within H. annosum-related gaps will increase substantially over time as compared with closed-canopy areas.