Aims Lianas are expected to influence composition,structure and func-tioning of forest systems due to unequal distribution across the potential set of host plants.However,our understanding of mecha-nisms associated wi...Aims Lianas are expected to influence composition,structure and func-tioning of forest systems due to unequal distribution across the potential set of host plants.However,our understanding of mecha-nisms associated with preferences for specific hosts is still limited,and so is our ability to discern between endogenous and exogenous forces driving forest dynamics in the long run.In this paper,we eval-uated whether the dominant liana Hedera helix can indirectly con-tribute to the eventual dominance of the small multi-stemmed tree Corylus avellana in a remnant temperate forest in central Iberian Peninsula from comparatively reduced liana infestation on C.avel-lana relative to co-occurring woody species.Methods through principal component analysis and co-occurrence ana-lysis,we studied the distribution and spatial association between woody species and the liana H.helix.We analyzed the relationship between the number of species in a plot and the number of species infested by the liana to test the hypothesis that H.helix is a gen-eralist liana.through generalized linear mixed models,we tested the dynamic-multi-stemmed growth form of C.avellana as a plaus-ible life strategy to withstand,in the long run,the liana infestation.In particular,we tested(i)the relationship between stem size and the probability of H.helix infestation including all the tree species within plots and(ii)the relationship between stem size and mortal-ity as evidence of the stem turn over in the tree C.avellana.Important Findings Our results indicate that H.helix and C.avellana significantly co-occur in mature stands of this remnant temperate forest where pion-eer woody species are absent.Hedera helix severely infests all the woody species whenever stem size exceed≈25 cm perimeter and there is physical contact at the base of the stem.this implies that all the trees in the community are potential hosts for H.helix.Mixed models indicate that both,infestation by H.helix and stem mortality,are positively related to C.avellana stem perimeter.Reduced long-term infestation of the liana by means of a multi-stemmed growth form with high stem turnover in C.avellana might be an advantage with respect to unipodial tree species.thus,the liana-tree coexistence pattern may be interpreted as an indirect positive interaction that,contrary to previous findings,results here in species dominance instead of species coexistence.展开更多
基金J.M.G.was granted with a Postdoctoral Fellowship at the University of Alcalá.E.G.thanks support of FONDECYT grant 1140070The last sampling period was funded by the FUNDIVER project(MINECO:CGL2015-69186-C2-2-R).
文摘Aims Lianas are expected to influence composition,structure and func-tioning of forest systems due to unequal distribution across the potential set of host plants.However,our understanding of mecha-nisms associated with preferences for specific hosts is still limited,and so is our ability to discern between endogenous and exogenous forces driving forest dynamics in the long run.In this paper,we eval-uated whether the dominant liana Hedera helix can indirectly con-tribute to the eventual dominance of the small multi-stemmed tree Corylus avellana in a remnant temperate forest in central Iberian Peninsula from comparatively reduced liana infestation on C.avel-lana relative to co-occurring woody species.Methods through principal component analysis and co-occurrence ana-lysis,we studied the distribution and spatial association between woody species and the liana H.helix.We analyzed the relationship between the number of species in a plot and the number of species infested by the liana to test the hypothesis that H.helix is a gen-eralist liana.through generalized linear mixed models,we tested the dynamic-multi-stemmed growth form of C.avellana as a plaus-ible life strategy to withstand,in the long run,the liana infestation.In particular,we tested(i)the relationship between stem size and the probability of H.helix infestation including all the tree species within plots and(ii)the relationship between stem size and mortal-ity as evidence of the stem turn over in the tree C.avellana.Important Findings Our results indicate that H.helix and C.avellana significantly co-occur in mature stands of this remnant temperate forest where pion-eer woody species are absent.Hedera helix severely infests all the woody species whenever stem size exceed≈25 cm perimeter and there is physical contact at the base of the stem.this implies that all the trees in the community are potential hosts for H.helix.Mixed models indicate that both,infestation by H.helix and stem mortality,are positively related to C.avellana stem perimeter.Reduced long-term infestation of the liana by means of a multi-stemmed growth form with high stem turnover in C.avellana might be an advantage with respect to unipodial tree species.thus,the liana-tree coexistence pattern may be interpreted as an indirect positive interaction that,contrary to previous findings,results here in species dominance instead of species coexistence.
