Stem Diameter and Height as Traits Linked to Cork Quality (Thickness and Porosity) in Cork Oak (Quercus suber L.)

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Stem Diameter and Height as Traits Linked to Cork Quality (Thickness and Porosity) in Cork Oak (Quercus suber L.)

AUGUSTA COSTA, INÊS BARBOSA

Abstract. Thickness and porosity are properties of raw (natural) cork planks that have strong influence on the end-product quality, particularly on natural cork stoppers or discs, both highly valued natural cork products. In cork oak (Quercus suber L.), the between-trees variability of cork quality (thickness and porosity) is relatively well known and has been extensively studied. However, the within-tree variability of these properties has been scarcely addressed in the literature. In this study, we have focused on the within-tree variability of cork quality. Our major working hypothesis is that the within-tree variability of cork quality is related with trees specific growth patterns. We assessed, at tree individual level, the stem height-cork thickness and the stem height-cork porosity relationships that, so far, were not clear. Eventually, the patterns of radial growth, along the stem upwards may have a strong physiological basis. Our results showed: i) a stem height-cork thickness relationship, with trees showing a decrease of the cork thickness with the stem height and; (ii) a stem height-cork porosity relationship, with trees showing a decrease in the cork porosity with the stem height. Forest managers and cork processors require more quantitative information on the inter- and intra-stem variation of cork-thickness and cork-porosity in order to understand the effects of forest management decisions at cork oak woodlands level. This way, the modeled stem profiles of cork quality (thickness and porosity) allow the optimization of high quality raw cork (planks) and determine the economic feasibility of cork harvesting practices.

Keywords
Raw Cork Planks, Stem Profile of Cork Quality, Linear Mixed Models

Published online 9/20/2019, 6 pages
Copyright © 2019 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: AUGUSTA COSTA, INÊS BARBOSA, Stem Diameter and Height as Traits Linked to Cork Quality (Thickness and Porosity) in Cork Oak (Quercus suber L.), Materials Research Proceedings, Vol. 14, pp 1-6, 2019

DOI: http://dx.doi.org/10.21741/9781644900413-1

The article was published as article 1 of the book Cork Science and its Applications II

References
[1] A. Costa, H. Pereira, Influence of cutting direction of cork planks on the quality and porosity characteristics of natural cork stoppers, Forest Systems 19(1) (2010) 51-60. https://doi.org/10.5424/fs/2010191-01166
[2] H. Pereira, O calibre e a porosidade como parâmetros da qualidade tecnológica da cortiça em prancha, Revista Florestal XI (2) (1998) 46-50.
[3] N. Beja, Influência da qualidade das pranchas de cortiça no rendimento e no perfil de qualidade das rolhas de cortiça natural. MSc Thesis, Tecnhical University of Lisbon , 145 pp.
[4] A. Costa, H. Pereira, Quality characterization of wine cork stoppers using computer vision, J. Int. Sci. Vigne Vin. 39(4) (2005) 209-218. https://doi.org/10.20870/oeno-one.2005.39.4.887
[5] H. Pereira, Cork: Biology, Production and Uses, first ed.. Elsevier Publications, Amsterdam, 2007. https://doi.org/10.1016/B978-044452967-1/50013-3
[6] G. Montero G, and R. Vallejo, Variacion del calibre del corcho medido a distintas alturas, Invest.Agrar. Sist. Recur. For. 1(2) (1992) 181-188.
[7] C.Taco, F. Lopes, H. Pereira, La variation dans l’arbre de l’épaisseur du liége et du dos des planches de liége pour des chênes-liéges en pleine production,” Ann. Inst. Sup. Agronom. 49 (2003) 209-221.
[8] F. González, J.R. González, J.L. García de Ceca, d M. González,Variabilidad de los parametros característicos del corcho en plancha con la altura de extracción, III Congreso Forestal Español “Montes para la Sociedad del Nuevo Milenio” pp.6, 2001.
[9] J.V. Natividade, Subericultura, first ed. Ministério da Agricultura, Pescas e Alimentação, Direcção-Geral das Florestas, Lisbon, 1950.
[10] J.V. Natividade, O problema da qualidade da cortiça nos sobreirais do norte do Tejo, Boletim da Junta nacional da Cortiça 8 (1939) 5-16.
[11] D.P. Machado, Contribuição para o estudo da formação da cortiça no sobreiro, Revista Agronómica XXIII (2) (1935) 83-109.
[12] M.P. Mendes, P. Cherubini, T. Plieninger, L. Ribeiro, and A. Costa, Climate effects on stem radial growth of Quercus suber L.: does tree size matter?, Forestry 92(1) (2019) 73-84. https://doi.org/10.1093/forestry/cpy034