Lavergne A., Daux V., Villalba R., Pierre M., Stievenard M., Vimeux Françoise, Srur A. M. (2016). Are the oxygen isotopic compositions of Fitzroya cupressoides and Nothofagus pumilio cellulose promising proxies for climate reconstructions in northern Patagonia ?. Journal of Geophysical Research : Biogeosciences, 121 (3), p. 767-776. ISSN 2169-8953.
Titre du document
Are the oxygen isotopic compositions of Fitzroya cupressoides and Nothofagus pumilio cellulose promising proxies for climate reconstructions in northern Patagonia ?
Lavergne A., Daux V., Villalba R., Pierre M., Stievenard M., Vimeux Françoise, Srur A. M.
Source
Journal of Geophysical Research : Biogeosciences, 2016,
121 (3), p. 767-776 ISSN 2169-8953
Tree ring O-18 chronologies from two native species (Fitzroya cupressoides and Nothofagus pumilio) in northern Patagonia were developed to assess their potential for paleoclimate reconstructions. The five annually resolved cellulose O-18 chronologies (two for F. cupressoides and three for N. pumilio) are located on the Andes along the steep west-to-east precipitation gradient. Over the common 60years long interval, the five site-O-18(cell) chronologies exhibit a strong common signal as indicated by the significant mean intercorrelation (r=0.61, p<0.05) and the high percentage (65%) of total variance explained by the first empirical orthogonal function. Although correlation analyses reveal that the two mean species-O-18(cell) chronologies are mainly modulated by December-May temperature, the N. pumilio chronology shows a greater sensitivity to record temperature variations (r=0.57, p<0.05). The O-18(cell) of N. pumilio contains a regional temperature signal representative of a large area in southern South America under the influence of the Southern Annular Mode. This study indicates that O-18(cell) in N. pumilio is a promising proxy to reconstruct past variations in temperature in South America south of 38 degrees S.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020]
;
Sciences du milieu [021]
;
Sciences du monde végétal [076]
;
Etudes, transformation, conservation du milieu naturel [082]
