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Báo cáo khoa học: "Relation between ecological conditions and fir decline in a sandstone region of the Vosges mountains (northeastern France) Anne-Laure Thomasa, Jean-Cl."

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Relation between ecological conditions and fir decline in a sandstone region of the Vosges mountains (northeastern France) Anne-Laure Thomasa, Jean-Cl. | 265 Ann. For. Sci. 59 2002 265-273 INRA EDP Sciences 2002 DOI 10.1051 forest 2002022 Original article Relation between ecological conditions and fir decline in a sandstone region of the Vosges mountains northeastern France Anne-Laure Thomasa Jean-Claude Gégoutb Guy Landmannc Étienne Dambrined and Dominique Kinga a Unite Science du Sol SESCPF INRA 45160 Ardon France bUnité Écosystèmes Forestiers et Dynamique du Paysage ENGREF 14 rue Girardet CS 4216 54042 Nancy Cedex France c DERF Département de la SantédesForêts Ministère de l Agriculture etde laPêche 19 avenue du Maine 75732 Paris Cedex 15 France d Centre de Recherches Forestières INRA Champenoux 54280 Nancy France Received 1st December 1999 accepted 14 December 2001 Abstract - The present study re-examines the influence of ecological conditions on the health of silver fir Abies alba measured in 1989 during the so-called forest decline crisis in the sandstone portion of the Vosges mountains on the basis of an assessment of almost 3000 forest management units 10-20 ha each . Relationships between defoliation and needle yellowing related to Mg deficiency and environmental factors were analysed with contingency tables and modelled using discriminant functions. The results confirmed the predominant influence of altitude and stand age these two factors explain 70 of the spatial variability of defoliation and 64 of that of yellowing. In addition a database composed of 178 soil analytical profiles was analysed in relation to the geographic database. The commonly used variable altitude appeared to combine the influence of several related variables which are crucial for the biological functioning of the tree especially the plant available water holding capacity and chemical characteristics were negatively correlated with elevation in the study area. This ecological feature is likely to be common to a number of mid-elevation mountain range in Europe and was often neglected in the earlier studies on forest decline. forest .