tailieunhanh - Báo cáo khoa học: "Intraspecific variation of growth and adaptive traits in North American oak specie"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Intraspecific variation of growth and adaptive traits in North American oak species. | 153s Ann Sci For 1993 50 Suppl 1 153s-165s Elsevier INRA Review article Intraspecific variation of growth and adaptive traits in North American oak species HB Kriebel School of Natural Resources Division of Forestry The Ohio state University Wooster OH 44691-4096 USA Summary Variation of growth and adaptive traits has been identified in Quercus rubra L which has recognizable geographic patterns in replicated test plantations in the central and western parts of the species range. Traits varying geographically include growth rate drought resistance cold resistance time of flushing and leaf senescence. Patterns may differ in tests in southern regions. In Quercus falcata Michx coastal plain sources are superior to others in both central Mississippi and western South Carolina. In 3 partial-range Quercus pagoda Raf tests local or regional sources outrank others in growth and adaptability. Both of these species vary widely in cold hardiness. Local trees of Quercus alba L are above the average height of all Indiana trees at age 5 yr in southern Indiana but local trees of Quercus macrocarpa Michx in Nebraska are not as fast-growing as trees from seed sources 160 km south. Range-wide patterns remain undefined in both of these species. Among western provenances of Quercus nigra L in Louisiana flushing is latest in trees of the northernmost origins. Only fragmentary information is available on variation of growth and adaptive traits in 7 other oaks all eastern North American species. Quercus I oaks I variation growth adaptive traits hardiness Resume Variabilité intraspecifique des caractères d adaptation et de croissance Chez les espèces d Amerique du Nord. La varíabilité des caractères de croissance et d adaptation a été étu-diée Chez Quercus rubra L des gradients de variation ont clairement pu être établis chez cette es-pèce au vu des résultats obtenus dans des plantations installées dans la partie centrale et occiden-tale de I aire naturelie. Les caractères dont la .