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Báo cáo khoa học: "Tree-ring characteristics of subalpine fir (Abies lasiocarpa (Hook.) Nutt.) in relation to elevation and climatic fluctuations"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Tree-ring characteristics of subalpine fir (Abies lasiocarpa (Hook.) Nutt.) in relation to elevation and climatic fluctuations. | 89 Ann. For. Sci. 57 2000 89-100 INRA EDP Sciences Original article Tree-ring characteristics of subalpine fir Abies lasiocarpa Hook. Nutt. in relation to elevation and climatic fluctuations Bernhard Erich Splechtnaa Jaroslav Dobrya b and Karel Klinkaa a Forest Sciences Department University of British Columbia Vancouver B.C. V6T 1Z4 Canada b Institute of Botany Czech Academy of Sciences 252 43 Pruhonice Czech Republic Received 4 May 1999 accepted 5 November 1999 Abstract - To determine the influence of elevation and year-to-year climatic fluctuations on radial growth and tree-ring properties of Abies lasiocarpa we sampled dominant trees in 49 second-growth stands on mesic sites in British Columbia. The earlywood latewood and total ring width and latewood and maximum density decreased significantly with increasing elevation. Since no significant trend was observed for latewood percentage and ring density decline in maximum density will have minor impacts on wood quality of high and low-elevation Abies lasiocarpa. The correlation and response functions indicated that response to climatic factors changed with elevation. Although mesic sites within the study area were not expected to be water deficient ring width decreased with the occurrence of warm and dry spring weather in low-elevation. Low summer temperature limited ring width in high-elevation and maximum latewood density and latewood width in low- and high-elevation albeit the relationship was much stronger in high-elevation. Abies lasiocarpa dendrochronology radial growth response function wood density Résumé - Caractéristiques des cernes annuels chez Abies lasiocarpa Hook. Nutt. en fonction de l altitude et des variations climatiques. On a échantillonné les arbres dominants au sein de 49 peuplements de seconde venue sur des stations moyennes de la Colombie-Britannique afin de déterminer l influence de l altitude et des variations climatiques sur la croissance radiale et les pro-priétés des cernes annuels chez