tailieunhanh - Báo cáo khoa học: "Radial variations in wood mineral element concentrations: a comparison of beech and pedunculate oak from the Belgian Ardennes"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Radial variations in wood mineral element concentrations: a comparison of beech and pedunculate oak from the Belgian Ardennes. | 253 Ann. For. Sci. 58 2001 253-260 INRA EDP Sciences 2001 Original article Radial variations in wood mineral element concentrations a comparison of beech and pedunculate oak from the Belgian Ardennes Valérie Penninckx Suzanne Glineur Wolf Gruber Jacques Herbauts and Pierre Meerts Laboratoire de génétique et d écologie végétales Université Libre de Bruxelles Chaussée de Wavre 1850 1160 Bruxelles Belgium Received 20 June 2000 accepted 25 September 2000 Abstract - Radial variations in wood mineral element concentrations N P Ca Mg K Mn Al were investigated in 5 oak trees a ring-porous species with typical heartwood and 5 beech trees a diffuse-porous to semi-ring porous wood species lacking typical heartwood growing on an ochreous brown earth in the Belgian Ardennes. Differences in concentration profiles were consistent with the difference in wood structure. Specifically oak had markedly higher concentrations in sapwood suggesting that nutrients are actively resorbed from senescing wood rings resulting in very low elemental concentrations in heartwood. Similarities between the two species including outwardly decreasing cation concentrations and a recent increase in Al concentration might be ascribed to a common environmental influence . soil leaching by acid rain. However the decrease in Mn concentration in both species is not consistent with a scenario of decreasing soil pH. Alternative explanations are discussed. dendrochemistry heartwood sapwood Fagus sylvatica Quercus robur beech oak soil acidification Résumé - Variations radiales des concentrations en elements minéraux du bois une comparaison entre hêtre et chêne pédonculé en Ardenne belge. Les variations radiales des teneurs en éléments minéraux N P Ca Mg K Mn Al ont été mesurées dans 5 chênes une essence à anneaux poreux et à bois de creur bien différencié et 5 hêtres une essence à porosité diffuse et dépour-vue de bois de creur bien différencié croissant sur sol brun ocreux dans le massif ardennais belge. Les