tailieunhanh - Báo cáo lâm nghiệp: "The successional status of tropical rainforest tree species is associated with differences in leaf carbon isotope discrimination and functional traits"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: The successional status of tropical rainforest tree species is associated with differences in leaf carbon isotope discrimination and functional traits. | Ann. For. Sci. 64 2007 169-176 INRA EDP Sciences 2007 DOI forest 2006101 169 Original article The successional status of tropical rainforest tree species is associated with differences in leaf carbon isotope discrimination and functional traits Damien BONALa Céline BORNa Claude BRECHETb Sabrina Coste Eric MARCONa Jean-Christophe ROGGYa Jean-Marc GUEHLb a INRA Kourou UMR Écologie des Forêts de Guyane BP 709 97387 Kourou Cedex Guyane France b INRA Nancy UMR Écologie et Écophysiologie 54280 Champenoux France Received 24 April 2006 accepted 30 June 2006 Abstract - We characterised the among species variability in leaf gas exchange and morphological traits under controlled conditions of seedlings of 22 tropical rainforest canopy species to understand the origin of the variability in leaf carbon isotope discrimination A among species with different growth and dynamic characteristics successional gradient . Our results first suggest that these species pursue a consistent strategy in terms of A throughout their ontogeny juveniles grown here versus canopy adult trees from the natural forest . Second leaf A was negatively correlated with WUE and N and positively correlated with gs but among species differences in A were mainly explained by differences in WUE. Finally species belonging to different successional groups display distinct leaf functional and morphological traits. We confirmed that fast growing early successional species maximise carbon assimilation with high stomatal conductance. In contrast fast and slow growing late successional species are both characterised by low carbon assimilation values but by distinct stomatal conductance and leaf morphological features. Along the successional gradient these differences result in much lower A for the intermediate species . fast growing late successional as compared to the two other groups. 13C functional diversity leaf gas exchange species grouping tropical rainforest Résumé - Le statut successionnel des .