tailieunhanh - Báo cáo lâm nghiệp: "Composition, distribution and supposed origin of mineral inclusions in sessile oak wood – consequences for microdensitometrical analysis"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Composition, distribution and supposed origin of mineral inclusions in sessile oak wood – consequences for microdensitometrical analysis. | Ann. For. Sci. 64 2007 11-19 INRA EDP Sciences 2007 DOI forest 2006083 11 Original article Composition distribution and supposed origin of mineral inclusions in sessile oak wood - consequences for microdensitometrical analysis Dries VANSTEENKlSTEa Joris Van ACKERa Marc STEVENSa Didier LE THlECb Gérard NEPVEUc a Ghent University Faculty of Bioscience Engineering Dept. Forest and Water Management Section Wood Biology and Wood Technology Coupure Links 653 9000 GENT Belgium b INRA Nancy UMR Écologie et Écophysiologie Forestières INRA-UHP Nancy I 1137 Équipe Bioclimatologie 54280 Champenoux France c INRA Nancy Laboratoire d Étude des Ressources Forêt-Bois UMR INRA-ENGREF 1092 Équipe de Recherches sur la Qualité des Bois 54280 Champenoux France Received 14 December 2005 accepted 8 September 2006 Abstract - SEM and light-microscopical observations supported by chemical microanalysis with an EDXA system revealed that light-saturated pixels observed in X-ray negatives of sessile oak Quercus petraea Liebl. wood were caused by inorganic deposits present inside multiseriate ray and axial parenchyma cells. Calcium oxalate crystals silica grains and amorphous granules with varied mineral compositions have been identified. The wood strips of three out of six sampled trees contained measurable amounts of mineral inclusions which were quantified using image analysis. Based on the variations of mineral content observed between trees and within and between annual rings of the same tree some hypotheses were formulated concerning the factors involved in the formation of inorganic deposits in oak wood. Their occurrence varies depending on the mineral concerned and seems to be controlled largely by a tree effect. The time of formation appears to coincide with a shifting of the oak wood s functions as a result of heartwood formation processes inter-annual scale or changes in leaf phenology and climate intra-annual scale . In addition the technical consequences of their presence as