Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí lâm nghiệp đề tài: A fractal root model applied for estimating the root biomass and architecture in two tropical legume tree species. | Ann. For. Sci. 61 2004 337-345 INRA EDP Sciences 2004 DOI forest 2004027 337 Original article A fractal root model applied for estimating the root biomass and architecture in two tropical legume tree species Eduardo SALASa Harry OZIER-LAFONTAINEb Pekka Nygrenc a Escuela de Fitotecnia Universidad de Costa Rica Ciudad Universitaria Rodrigo Facio San Pedro de Montes de Oca Costa Rica b UR Agropédoclimatique INRA Centre Antilles-Guyane Domaine Duclos 97170 Petit Bourg Guadeloupe France c Department of Forest Ecology PO Box 27 00014 University of Helsinki Finland Received 31 January 2003 accepted 20 August 2003 Abstract - A fractal root model with parameter estimation based on pipe model theory was applied for studying root architecture of Erythrina lanceolata and Gliricidia sepium associated with crops in agroforestry. The results were compared with a theoretical volume-filling fractal model on scaling of plant vascular system. Scaling of root diameter at bifurcation followed same parameter values over the whole root system. The parameter values were approximately equal in both species. Length between two bifurcations could not be estimated according to volumefilling fractal principles but an empirical regression was used. An empirical model was also applied for estimating bifurcation angles. These characteristics seem to respond strongly to local root environment and their modelling calls for studying root-soil interactions. Agronomic applications of this study indicate the usefulness of an architectural approach for the study of belowground interactions in agroforestry systems. Erythrina lanceolata Gliricidia sepium agroforestry pipe model self-similarity Résumé - Application d un modèle racinaire fractal à l estimation de la biomasse et de l architecture racinaire de deux espèces d arbres légumineux. Un modèle racinaire fractal dont l estimation des paramètres repose sur la théorie du modèle vasculaire a été appli-qué à l étude de l architecture de Erythrina