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Báo cáo lâm nghiệp:"Predicting the probability of seed germination in Pinus sylvestris L. and four competitor shrub species after fire"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí lâm nghiệp đề tài:"Predicting the probability of seed germination in Pinus sylvestris L. and four competitor shrub species after fire" | Ann. For. Sci. 60 2003 75-81 INRA EDP Sciences 2003 DOI 10.1051 forest 2002076 75 Original article Predicting the probability of seed germination in Pinus sylvestris L. and four competitor shrub species after fire Ma Rosario Nuneza Felipe Bravoa and Leonor Calvob a Departamento de Production Vegetal y Silvopascicultura E.T.S. de Ingenierías Agrarias Universidad de Valladolid Avda. de Madrid n 57 34004 Palencia Spain b Área de Ecología Facultad de Ciencias Biológicas y Ambientales Universidad de León 24071 León Spain Received 8 April 2002 accepted 4 June 2002 Abstract - Knowledge of the regeneration of competing shrub species after wildfire in Scots pine stands is essential for the regeneration of this tree species. The germination capability of seeds is modified by the temperature reached during a fire and the length of time that seeds are subjected to high temperatures. The probability of germination was studied in the laboratory for Scots pine Pinus sylvestris and four shrub species characteristic of the understory in Scots pine stands in northern Spain Cistus laurifolius Halimium umbellatum Halimium alyssoides and Genista florida . Germination probability was studied with a logistic model that uses duration of exposure to the fire the temperature and the interaction of both as independent variables. Results show a higher germination rate in shrub species at high temperature than for Scots pine. Thus by limiting competition between Scots pine and understory species using prescribed burning or mechanical site preparation Scots pine can regenerate successfully and quickly. This model can aid management decisions in this area. germination scots pine shrub species thermal shock Résumé - Prédiction des probabilités de germination après le feu de Pinus sylvestris L. et de quatre espèces de garrigue. La regeneration des espèces de garrigue après le feu est un facteur determinant pour la réinstallation de Pinus sylvestris. La temperature pendant l incendie et la duree de