Las micorrizas en plántulas de Quercus están afectadas por el decaimiento del alcornocal

Micorriza_BeaIn forests affected by problems of tree dieback, tree health status could be an additional factor shaping mycorrhizal abundance in soils, which in turn could affect the probability of seedling establishment in a feed-back process.

A research team in the IRNAS has studied how cork oak (Quercus suber) decline can impact the spatial patterns of seedling-mycorrhiza interactions, and has evaluated the relative importance of this symbiosis as a driver of seedling establishment. Using a Bayesian approach, models were developed to explain how tree identity and spatial distribution shape the spatial patterns of mycorrhiza, and how the interaction with seedlings affects forest regeneration dynamics.

The spatial variability found in the patterns of oak seedling colonization by both arbuscular mycorrhizas and ectomycorrhizas was partially linked to the process of Q. suber decline. Moreover, seedling survival and growth was influenced by the intensity of mycorrhiza colonization, but in quite unexpected ways. Arbuscular mycorrhiza had a larger effect on seedling performance than ectomycorrhizal, and the effects of both groups were negative or neutral but never positive.

The results indicate that because the spatial distribution of the seedling-mycorrhiza association responded to the identity and health of individual trees, and mycorrhizal infection did in turn affect seedling performance, tree decline may affect forest dynamics through changes in plant-soil biota feedbacks. Overall this information will be extremely valuable to evaluate the adequacy of restoration tools involving plant-mycorrhiza interactions, generating the knowledge base needed to optimize the management of declining forests.

This study, which is part of the Beatriz Ibáñez Ph.D. Dissertation, has been published in the journal Forest Ecology and Management.

Ibáñez, B., Gómez-Aparicio, L., Ávila, J. M., Pérez-Ramos, I. M., García, L. V., & Marañón, T. (2015). Impact of tree decline on spatial patterns of seedling-mycorrhiza interactions: Implications for regeneration dynamics in Mediterranean forests. Forest Ecology and Management (in press) doi:10.1016/j.foreco.2015.05.014

Comments are closed.