tailieunhanh - Báo cáo khoa học: " Rôle de la nutrition minérale et de l’approvisionnement en eau sur la croissance du pin laricio de Corse dans l’ouest de la France"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: " Rôle de la nutrition minérale et de l’approvisionnement en eau sur la croissance du pin laricio de Corse dans l’ouest de la France". | Ann Sci For 1997 54 279-300 Elsevier INRA 279 Article original Rôle de la nutrition minérale et de 1 approvisionnement en eau sur la croissance du pin laricio de Corse dans 1 ouest de la France F Lebourgeois1 G Levy2 M Becker1 Y Lefevre 2 1Équipe phytoécologie 2Équipe sol et nutrition unite d ecophysiologie forestiere Inra-Nancy 54280 Champenoux France Reẹu le 6 décembre 1995 accepté le 13 fevrier 1996 Summary - Effects of mineral nutrition and water site conditions on radial growth of Corsican pine in western France. The importance of mineral nutrition and soil water regime water soil reserve index and lateral water supply for the radial growth of 1 808 mature Corsican pines Pinus nigra Arnold ssp laricio Poiret var Corsicana average age 30 years sampled in 183 sites in western France Pays de la Loire region was studied. Foliage and chemical soil analyses indicate that growth depends exclusively on phosphorus nutrition. The optimal p foliar concentration is N P foliage ratio 10 the critical value is N P 14 and the deficiency level is N P 18 . Needle content of other nutrients is sufficient for tree requirements and does not differ between trees with different growth levels. The average concentrations are and for N Ca Mg K respectively. The response of trees to phosphorus is greater on moist sites than on dry sites but considerably decreases during drought periods. Soil water regime which is found to predispose trees to climatic variations may locally accentuate the effects of exceptionally dry years and hence induce durable radial growth decrease and subsequently forest decline. However low competition between trees seems to be able to decrease the intensity of dryness by minimizing water competition within stands. In order to improve the radial growth of Corsican pine plantations the best advice is to avoid this species on sites clearly unfavourable for mineral nutrition and or for water supply and to apply an adequate .