Editor's Picks
Plant Focus

To create an account click here; if you have already registered, click here to become a member.
Individual articles can be purchased for U$S 10. If you would like to purchase an article, email a request to website@internationaloaksociety.org
João P.F. Carvalho
Published May 2023 in International Oaks No. 34: 81–90
Abstract
Natural recruitment and survival of Quercus ilex L. subsp. ballota (Desf.) Samp. is difficult largely due to degraded ecological conditions. A comparative study was undertaken in the northeast region of Portugal in order to evaluate the survival of Q. ilex subsp. ballota seedlings established in two contiguous areas, one inside and one outside a naturally regenerated young stand of Juniperus oxycedrus L. (prickly juniper). The environmental conditions in both the “inside” and the “outside” study areas were studied to further understand the assisted regeneration process. Over a growing season, photosynthetically active radiation (PAR), air and soil temperature (Tair , Tsoil), relative humidity (RH), soil water content (SWC), andplant water potential (Ψ ) were measured. Maximum differences for these parameters were calculated. Higher mortality of Q. ilex subsp. ballota seedlings was observed in the outside area, where environment conditions are harsher. The J. oxycedrus canopy provides more favorable conditions, thus playing an important role in enabling and facilitating the establishment and survival of the oak seedlings. Natural dynamics and management implications regarding the importance of J. oxycedrus for the restoration of Q. ilex subsp. ballota stands are analyzed.
Keywords
regeneration, establishment conditions, facilitation
References
Benayas, J. 1998. Growth and mortality of Quercus ilex L. seedlings after irrigation and artificial shading in Mediterranean set-aside agricultural lands. Ann. Sci. For. 55: 801-807.
Benayas, J., and A. Cruz. 2004. Performance of Quercus ilex saplings planted in abandoned Mediterranean cropland after long-term interruption of their management. For. Ecol. Management 194: 223-240.
Benayas, J., J. Navarro, T. Espigares, J. Nicolau, and M. Zavala. 2005. Effects of artificial shading and weed mowing in reforestation of Mediterranean abandoned croplands with contrasting Quercus species. For. Ecol. Management 212: 302-214.
Brooker, R. 2006. Plant–plant interactions and environmental change. New Phytologist 171: 271-289.
Callaway, R. and C. D’Antonio. 1991. Shrub facilitation of coast live oak establishment in central California. Madroño 38: 158-169.
Callaway, R. 1992. Effect of shrubs on recruitment of Quercus douglasii and Quercus lobata in California. Ecology 73: 2118-2128.
Callaway, R. 1995. Positive interactions among plants. Bot. Rev. 61: 306-349.
Castro, J., R. Zamora, J. Hódar, J. Gómez, and L. Gómez-Aparicio. 2004. Benefits of using shrubs as nurse plants for reforestation in Mediterranean mountains: a 4-year study. Restor. Ecol. 12: 352-358.
Corcuera, L., J. Camarero, and E. Gil-Pelegrin. 2004. Effects of a severe drought on Quercus ilex radial growth and xylem anatomy. Trees 18: 83-92.
Cuesta, B., P. Villar-Salvador, J. Puértolas, J. Benayas, and R. Michalet. 2010. Facilitation of Quercus ilex in Mediterranean shrubland is explained by both direct and indirect interactions mediated by herbs. Journal of Ecology 98: 687-696.
Debazac, E. 1983. Temperate broad-leafed evergreen forest of the Mediterranean region and Middle East. In Ecosystems of the world, edited by J. Ovington. Amsterdam: Elsevier.
Gómez-Aparicio, L., F. Valladares, and R. Zamora. 2006. Differential light responses of Mediterranean tree saplings: linking ecophysiology with regeneration niche in four co-occurring species. Tree Physiology 26: 947-958.
Grime, J. 2002. Plant strategies, vegetation processes and ecosystem properties. New Jersey: John Wiley & Sons. IFN. 2015. 6 National Forest Inventory, ICNF, Lisbon.
IFN. 2018. 4 National Forest Inventory, MTERD, Madrid.
IPCC. 2013. Contribution of working group I to the fifth assessment report of the intergovernmental panel on climate change. In Climate change 2013: the physical science basis, edited by T. Stocker, D. Qin, G. Plattner, M. Tignor, S. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex, P. Midgley. New York: Cambridge University Press.
Maldonado, Y., J. Staniswalis, L. Irwin, and D. Byers. 2002. A similarity analysis of curves. The Canadian Journal Statistics 30(3): 37-381.
Maestre, F., and J. Cortina. 2004. Do positive interactions increase with abiotic stress? A test from a semi-arid steppe. Proceedings of the Royal Society of London. Series B: Biological Sciences 271(Suppl. 5): S331-S333.
Marañon, T., R. Zamora, R. Villar, M. Zavala, J. Quero, I. Perez-Ramos, I. Mendoza, and J. Castro. 2004. Regeneration of tree species and restoration under contrasted Mediterranean habitats: field and glasshouse experiments. International Journal Ecology and Environmental Sciences 30(3): 187-196.
Milchunas, D., and I. Noy-Meir. 2002. Grazing refuges, external avoidance of herbivory and plant diversity. Oikos 99(1): 113-130. Morán-López, T., M. Fernández, C. Alonso, D. Flores-Rentería, F. Valladares, and M. Díaz. 2015. Effects of forest fragmentation on the oak-rodent mutualism. Oikos 124: 1482-1491.
Nijland, W., E. Jansma, E. Adink, M. Domínguez Delmás, and S. De Jong. 2011. Relating ring width of Mediterranean evergreen species to seasonal and annual variations of precipitation and temperature. Biogeosciences 8: 1141-1152.
Noble, I., and R. Slayter. 1980. The use of vital attributes to predict successional changes in plant communities subject to recurrent disturbance. Vegetation 43: 5-21.
Pesoli, P., L. Gratani, and W. Larcher. 2003. Response of Quercus ilex from different provenances to experimentally imposed water stress. Biol. Plantarum 46: 577-581.
Plieninger, T., V. Rolo, and G. Moreno. 2010. Large-scale patterns of Quercus ilex, Quercus suber, and Quercus pyrenaica regeneration in Central-Western Spain. Ecosystems 13: 644-660.
Puerta-Piñero, C., J. Gomez, and F. Valladares. 2007. Irradiance and oak seedling survival and growth in a heterogeneous environment. For. Ecol. Management 242: 462-469.
Ribeiro, N., P. Surovy, C. Dinis, C. Camilo-Alves, and S. Dias. 2016. Inventário Nacional de Mortalidade de Azinheira na Fotografia
Aérea Digital de 2004/2006. Ed Univ Evora - Silabas Desafios Unipessoal, Faro.
Rodá, F., J. Retana, C. Gracia, and J. Bellot. 1999. Ecology of Mediterranean evergreen oak forests. New York: Springer.
Rousset, O., and J. Lepart. 2000. Positive and negative interactions at different life stages of a colonizing species (Quercus humilis). J. Ecol. 88: 401-412.
Santos, T., and J. Tellería. 1997. Vertebrate predation on Holm Oak, Quercus ilex, acorns in a fragmented habitat: effects on seedling recruitment. For. Ecol. Management 98: 181-187.
Scholander, P., H. Hammel, E. Bradstreet, and E. Hemmingsen. 1965. Sap pressure in vascular plants. Science 148: 339-346.
Serrano, L., and J. Peñuelas. 2005. Contribution of physiological and morphological adjustments to drought resistance in two Mediterranean tree species. Biol. Plantarum 49: 551-559.
Thirgood, J. 1981. Man and the Mediterranean Forest, a history of resource depletion. London: Academic Press.
Valladares, F., R. Benavides, S. Rabasa, S. Paula, W. Simonson, and M. Díaz. 2014. Global change and Mediterranean forest: current impacts and potential responses. In Forests and global change, edited by D.A. Coomes, D.F.R.P. Burslem, and W.D. Simson. Cambridge: Cambridge University Press.
Weltzin, J., and G. McPherson. 1999. Facilitation of conspecific seedling recruitment and shifts in temperate savanna ecotones. Ecol. Monogr. 64: 513-534.
Zar, J. 1996. Biostatistical analysis. New Jersey: Prentice Hall.
Zavala, M., J. Espelta, J. Caspersen, and J. Retana. 2011. Interspecific differences in sapling performance with respect to light and aridity gradients in Mediterranean pine–oak forests: implications for species coexistence. Canadian Journal Forest Research 41: 1432-1444.