Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Climatic significance of tree-ring width and intra-annual density fluctuations in Pinus pinea from a dry. | Ann. For. Sci. 64 2006 229-238 INRA EDP Sciences 2007 DOI forest 2006107 229 Original article Climatic significance of tree-ring width and intra-annual density fluctuations in Pinus pinea from a dry Mediterranean area in Portugal Filipe CAMPELOa Cristina NABAISa Helena FREITASa Emilia GUTIÉRREZb a Departamento de Botânica Universidade de Coimbra Calẹada Martim de Freitas 3001-455 Coimbra Portugal b Departament d Ecologia Facultat de Biologia Universitat de Barcelona Av. Diagonal 645 08028 Barcelona Spain Received 10 April 2006 accepted 19 June 2006 Abstract - In Mediterranean climates trees may go through two periods of dormancy resulting in special anatomical features such as false rings and other intra-annual density fluctuations IADFs . In this paper ring growth and the presence of IADFs were studied in Pinus pinea L. growing in the coastal and inland regions of Alentejo southern Portugal . In order to identify the triggering factors associated with the IADFs a new classification was proposed for the IADFs in P pinea Type E latewoodlike cells within earlywood Type E transition cells between earlywood and latewood Type L earlywoodlike cells within latewood and Type L earlywoodlike cells between latewood and earlywood of the next tree ring . Response function analyses showed that radial growth of P. pinea was strongly correlated with precipitation in southern Portugal. The climatic response of P. pinea was higher in the inland area where the summer drought is more severe the winter temperatures are lower and the soils have low water-holding capacity in comparison with the coastal area. IADFs were frequent in P pinea and most of the IADFs were observed in latewood. The presence of IADFs was correlated with fluctuations in climate parameters during the growing season. The IADF type E was linked to precipitation events early in summer. The IADF type L and L were associated with above-average precipitation in early autumn. false tree-ring Mediterranean climate
