RT info:eu-repo/semantics/article
T1 Shifting demographic conflicts across recruitment cohorts in a dynamic post-disturbance landscape
A1 Leverkus, Alexandro Bitol
A1 Rey Benayas, José María
A1 Castro, Jorge
K1 Biological legacy
K1 Garrulus glandarius
K1 Holm oak
K1 Life-stage conflict
K1 Ontogeny
K1 Pine plantation
K1 Plant demography
K1 Post-fire succession
K1 Quercus ilex
K1 Seed dispersal
K1 Medio Ambiente
K1 Environmental science
AB Seed dispersal effectiveness, which measures the number of adult plant individualsproduced by seed dispersal, is the product of the number of seeds dispersed and the probabilitya seed produces an adult. Directed dispersal to certain habitat types may enhance some stagesof recruitment but disfavor others, generating demographic conflicts in plant ontogeny. Weasked whether temporal changes in habitat features may affect the distribution of seedlingsrecruited from dispersed acorns, and whether this could induce shifts in the life-stageconflictsexperienced by successive cohorts of naturally recruited plants. As early successional habitatsare characterized by rapid change, we used a burnt pine stand in southern Spain to monitor therecruitment and performance of a major tree species (Quercus ilex) across 7 yr in four types ofpost-firehabitats. These differed in structure and included patches of unburnt forest and threemanagement alternatives of burnt trees: logging, partial cutting, and nonintervention. Youngoaks that resprouted after the fire were mainly located near acorn sources, while new seedlingsinitially emerged mostly in habitats with standing snags due to habitat selection by Europeanjays, Garrulus glandarius, for dispersal. The dead pines gradually collapsed and attracted lessdispersal, so subsequent seedling cohorts mainly recruited within patches of unburnt pines.These live pines enhanced the survival of the oaks located beneath their canopy but greatlyreduced their growth as compared to the other post-firehabitats, thus representing ademographic conflict that was absent elsewhere. As a consequence of the directional shift in thehabitat where seedlings recruited, successive seedling cohorts experienced a gradualimprovement in their likelihood of survival but a reduction in growth. The progressiveintensification of this life-stageconflict hinged on the reduction of vertical structures in thehabitat with standing burnt pines. Recruitment success thus involved temporal variation in thehabitat where recruitment occurred, likely resulting from changes in the direction of seeddispersal, and spatial variation in habitat suitability for seedling establishment and growth.Temporal changes in habitat structure can indirectly change the environment in whichrecruitment occurs, and consequently seed dispersal effectiveness, by shifting the direction ofseed dispersal.
SN 0012-9658
YR 2016
FD 2016
LK http://hdl.handle.net/10017/37757
UL http://hdl.handle.net/10017/37757
LA eng
NO Ministerio de Ciencia e Innovación
DS MINDS@UW
RD 25-abr-2024