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Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: " Variation of the photosynthetic capacity across a chronosequence of maritime pine correlates with needle phosphorus concentration" | Ann. For. Sci. 62 2005 537-543 INRA EDP Sciences 2005 DOI 10.1051 forest 2005046 537 Original article Variation of the photosynthetic capacity across a chronosequence of maritime pine correlates with needle phosphorus concentration Sylvain DELZONa b Alexandre BOSCa Lisa CANTETa Denis LOUSTAUa a Unité de Recherche EPHYSE INRA-Bordeaux 69 route d Arcachon 33610 Gazinet France b Present address UMR INRA 1202 BIOGECO Équipe Écologie des Communautés Université Bordeaux 1 Bât. B8 avenue des Facultés 33405 Talence France Received 2 August 2004 accepted 20 April 2005 Abstract - Changes in needle photosynthetic capacity has been studied across a chronosequence of four maritime pine stands aged 10- 32- 54- and 91-yr. We determined photosynthetic parameters from response curves of assimilation rate to air CO2 concentration A-Ci and radiation A-Q using gas exchange measurements on branches in the laboratory. Our data showed no shift in photosynthetic parameters Vcmax Jmax a and Rd with increasing stand age. This result means that the decline in productivity observed throughout our maritime pine chronosequence cannot be explained by a decrease in photosynthetic capacity but by a decline in stomatal conductance evidenced in a previous paper 7 . However Vcmax was higher in the 32-yr-old stand compared to the other stands and theses between-stand differences were explained by leaf phosphorus concentration. Moreover additional data of Vcmax suggest that the photosynthetic capacity may be higher at younger stages due to initial fertilisation. Therefore the P nutrition may contribute to productivity decline over the duration of the management cycle. Pinus pinaster Ait. forest aging NPP decline maximum carboxylation rate nutrient limitation Résumé - Les variations de la capacité de la photosynthèse des aiguilles de pin maritime dans une chronoséquence sont corrélées à celles des teneurs en phosphore. Nous avons étudié l évolution des capacités photosynthétiques foliaires dans une .
