Ecological Interactions between Cork Oak (Quercus suber L.) and Stone Pine (Pinus pinea L.): Results from a Pot Experiment

Abstract

Portuguese cork oak (Quercus suber L.) extended mortality and lack of regeneration have been the drivers of important changes in the traditional cork oak woodlands (savanna-like) montado. The decrease in tree cover fosters the mixture with stone pine (Pinus pinea L.) for pine-nut production providing shelter for oak regeneration. The use of nurse species, namely pines, to help Quercus spp. regeneration is known, but whether cork oak could be favoured by the mixture with stone pine remains a question. A pot experiment with cork oak (Qs) and stone pine (Pp) growing in inter-(Qs×Pp) and intraspecific mixtures (Qs×Qs, Pp×Pp) combinations and in monocultures, was installed in a greenhouse in Lisbon, Portugal. Morphological measurements of above- and belowground biomass components were carried out in 3 harvesting campaigns at 4, 8 and 11 months. Leaf nitrogen content and mycorrhizal symbiotic formations were quantified. During the seedling stage and under comfort water and nutrient conditions, the root growth and morphology of Qs and Pp showed contrasting patterns, suggesting complementary soil exploitation interactions in interspecific mixtures and potential competition in intraspecific mixtures. The mixture of Qs with Pp seems to be advantageous in the first stages of plant growth as Pp develop abundant mycorrhizae symbiosis formations which elicit mycorrhization of Qs plants coexisting in the same pot. This study suggests that stone pine can potentially help in establishing cork oak as seedlings, possibly facilitating nutrient uptake through mycorrhizae. However, complementary field studies are needed.

Growth and mortality of the oak processionary moth, Thaumetopoea processionea, on two oak species: direct and trait-mediated effects of host and neighbour species

“…Finally, neighbour-mediated effects on leaf traits can be also mediated by belowground processes. For example, plants have well documented effects on soil microbes which can in turn influence the growth and defences of their neighbours through plant-soil feedbacks (Pineda et al 2010;Van der Putten et al 2013;Kos et al 2015c, b;Correia et al 2018). Moreover, there is evidence that microbes in the rhizosphere of a plant can influence herbivory on another plant through changes in its leaf chemical content (Badri et al 2013).…”

Climate Change Impacts on Pinus pinea L. Silvicultural System for Cone Production and Ways to Contour Those Impacts: A Review Complemented with Data from Permanent Plots

“…In several situations, an increase in cone production has been observed in umbrella pines vegetating in zones subject to the fall of cork oak leaves in comparison with others implemented in contiguous zones where this fall did not occur, which is corroborated by the findings of [132] on Quercus influence on soil fertility. In turn, cork oaks take advantage from the mixture by an increase in plant growth in the first stages due to the umbrella pine abundant mycorrhizae development, symbiosis formations which elicit cork oaks plants mycorrhization, suggesting that stone pine can potentially help in establishing cork oak seedlings, possibly facilitating nutrient uptake through mycorrhizae [133]. Furthermore, cork oaks partially vegetating under umbrella pines canopies present greater vegetative vigor and less defoliation.…”

“…This relationship between individuals of different species, occupying several ecological niches, and interacting with each other, allows complementary soil exploitation interactions in interspecific mixtures stands [133] that are also more resistant to disturbances, such as those caused by droughts and/or storms [137], recovering more easily from catastrophic episodes than monospecific stands [138].…”

Multipurpose plant species and circular economy: Corylus avellana L. as a study case

“…Land restoration [34], green shelter and succession facilitation (biogroups) [35], niche for edible fungal species (incl. truffles) [36], propolis productions [37],…”

“…Between them, there are plenty of woody species of agro-forestry interest, which stand out for their multifunctional characteristics, as shown in Table 1 (Ref. [32][33][34][35][36][37][38][39][40][41][42]42,44,45]).…”