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Báo cáo khoa học: "Analysis and simulation of the architecture of a growing root system: application to a comparative study of several tree seedlings"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: "Analysis and simulation of the architecture of a growing root system: application to a comparative study of several tree seedlings. | 288s Ann. Sci. For. 1989 46 suppl. 288S-293S Forest Tree Physiology E. Dreyer et al. eds. Elsevier INRA Analysis and simulation of the architecture of a growing root system application to a comparative study of several tree seedlings M. Colin-Belgrand L. Pages2 E. Dreyer and H. Joannes 1 INRA Centre de Recherches Forestleres BP 35 54280 Seichamps and 2 INRA Station d Agronomie Domaine-de-St-Paul 84140 Montíavet France. Introduction It has frequently been suggested that the shape and the spatial extension of root systems markedly influence the rate and patterns of nutrient uptake from the soil. Many nutrient and water uptake models have been proposed based on root distribution patterns for instance spatial mostly vertical distribution of roots may be related to physical and chemical properties of successive soil layers as in the empirical model of Gerwitz and Pages 1973 . Parameters describing extension such as total root length explored soil volume and rooting density are frequently used. On the other hand a root system may also be described as a network of resistances to nutrient and water transfers. It appears therefore important not only to quantify root distribution but also to analyze the spatial ramified architecture in other words the connecting links between the different parts of the root system. Modeling root architecture The basis of root architecture modeling is an adequate definition of branching terminology. In this respect two main approaches may be outlined. The first one is based on a topological or morphometric description of ramifications. Fitter 1987 applied this approach to describe and simulate root systems of various herbaceous species. Basic structural units are the links straight segments between successive nodes branching points . The order of these links is counted from the periphery of the branching structure towards the primary axis hypocotyl . Main parameters are either topological like magnitude or geometric like link lengths branch .