Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí lâm nghiệp đề tài:"High-grading effects on Scots pine volume and basal area in pure stands in northern Spain" | 11 Ann. For. Sci. 60 2003 11-18 INRA EDP Sciences 2003 DOI forest 2002069 Original article High-grading effects on Scots pine volume and basal area in pure stands in northern Spain Felipe Bravoa and Gregorio Monterob a Dept. de Producción Vegetal y Silvopascicultura University of Valladolid Campus at Palencia Avda. de Madrid 44 34004 Palencia Spain b CIFOR-INIA PO Box 8011 28080 Madrid Spain Received 24 January 2002 accepted 25 March 2002 Abstract - A yield model for formerly high-graded Scots pine stands in a transitional climatic area in northern Spain has been developed. High grading practices were used broadly during the last decades. In the past years the silvicultural system has switched to a conventional even-aged system. A modeling approach is used to understand the effects of high-grading on basal area and dominant height. The equations are calibrated to be used in non high-graded stands and in previously high-graded stands when the silvicultural practices are switched. Dominant height and linear models were used to calibrate the original multiplicative model. With these models the effect of high-grading practices upon forest yield was studied. Standing volume decreased due to high-grading over 26 as the rotation age increased in a medium productivity class. The total volume reduction at rotation age was 18 . Pinus sylvestris high-grading yield Scots pine Spain Résumé - Effets du système de coupe à la dimension sur le volume et la surface terrière de peuplements de Pin sylvestre au nord de l Espagne. On a mis au point un modèle de croissance des peuplements de Pin sylvestre soumis auparavant à ce système dans une region climatique de transition située au nord de l Espagne. Ce type de sylviculture consistant à récolter systématiquement les arbres de gros diamètre a été courant au cours des dernières décennies. Depuis quelques années on abandonne cette methode pour adopter le traitement en futaie régulière. On a fait appel à l approche modélisation .
