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Báo cáo lâm nghiệp:" Structure, spatial distribution and competition in mixed jack pine (Pinus banksiana) stands on clay soils of eastern Canada"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí lâm nghiệp đề tài:" Structure, spatial distribution and competition in mixed jack pine (Pinus banksiana) stands on clay soils of eastern Canada" | Ann. For. Sci. 60 2003 609-617 INRA EDP Sciences 2004 DOI 10.1051 forest 2003053 609 Original article Structure spatial distribution and competition in mixed jack pine Pinus banksiana stands on clay soils of eastern Canada Martin BÉLANDa b Jean-Martin LUSSIERc Yves BERGERONa Marie-Hélène LONGPRÉa Michel BÉLANDd a Groupe de recherche en écologie forestière inter-universitaire et Chaire industrielle CRSNG-UQAT-UQAM en aménagement forestier durable Université du Québec en Abitibi-Témiscamingue Rouyn-Noranda Québec Canada b Present address Université de Moncton Edmundston Campus Faculty of Forestry Edmundston NB Canada c Canadian Forestry Service Laurentian Forestry Centre Québec Canada d Réseau québécois de calcul de haute performance Montréal Québec Canada Received 24 June 2002 accepted 31 March 2003 Abstract - The dynamics of pure jack pine Pinus banksiana stands and of those also comprising a component of white birch Betula papyrifera and trembling aspen Populus tremuloides was assessed in natural post-fire stands on clay soils of eastern Canada boreal mixed woods in order to shed some light on mechanisms controlling composition. Age structures indicated that the presence of birch or aspen merely shortened the establishment of jack pine. Basal area structures of jack pine showed lower skewness coefficients in mixtures with birch than in pure jack pine stands or when mixed with aspen indicating that birch is probably a weaker competitor. Its effect on mean pine diameter probably reflects the lower pine stem density when mixed with birch. Inter-specific competition however had no effect on pine diameter at the tree level. Competition between birch aspen and pine is avoided by species spatial exclusion measured by Ripley s statistic and reflects the reproductive strategies of the species and history of the site. Ripley s K asymmetric competition interspecific competition composition stand structure Résumé - Structure distribution spatiale et compétition dans les .