Đang chuẩn bị liên kết để tải về tài liệu:
Báo cáo khoa học: "Influence comparée de la saison sur la phénologie et sur les dégâts d’insectes phyllophages chez de jeunes individus d’arbres de forêt tropicale en Guyane française"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: "Influence comparée de la saison sur la phénologie et sur les dégâts d’insectes phyllophages chez de jeunes individus d’arbres de forêt tropicale en Guyane française. | Ann. Sci. For. 55 1998 715-725 Inra Elsevier Paris 715 Article original Influence comparée de la saison sur la phénologie et sur les dégâts d insectes phyllophages chez de jeunes individus d arbres de foret tropicale en Guyane franẹaise Pascal Gombauld Judy Rankin-de Mérona Station de recherches forestieres Inra BP 709 97387 Kourou cedex Guyane íranẹaise Reẹu le 29 juillet 1996 revise le 15 novembre 1996 accepté le 21 aoũt 1997 Abstract - Influence of season on phenology and insect herbivory on saplings of tropical rain forest trees in French Guiana. Leaf herbivory by insects as a function of season was quantified for saplings of five major tree species of a tropical rain forest in French Guiana. We determined the impact of herbivory based on the observed ratio of leaf area eaten to total leaf area attack ratio in a study of individual leaves on young saplings naturally established in undisturbed and adjacent logged forest. Measurements were conducted during the strongly contrasted dry and rainy seasons over a period of 10 months. The five species chosen for the study are Dicorynia guianensls Eperua falcata Eperua grandiflora Goupia glabra and Qualea rosea. For four of the five species leaf production varies significantly with season. D. guianensis is the only species of the five for which leaf production is maintained throughout the dry season. This has the effect of diminishing the relative impact of herbivory during a period when ground water deficits create conditions unfavorable for plant growth. Three other species experiencing high levels of herbivory during the dry season have significantly lower mean height growth than during the rainy season. In contrast D. guianensis and G. glabra have similar height growths regardless of season. Seasonal variation in leaf production and leaf attack also occur in similar proportions. The resulting attack ratios with the exception of E. grandiflora are not significantly different between the rainy season and dry season .