Climatic factors controlling radial growth and formation of wood density fluctuations in Austrocedrus chilensis in Valdivia, Chile

• Published in: Bosque (Valdivia)
• Main Authors: Rozas, Vicente, Le Quesne, Carlos, Rojas-Badilla, Moisés
• Format: Article in Journal/Newspaper
• Language: Spanish
• Published: Universidad Austral de Chile, Facultad de Ciencias Forestales y Recursos Naturales. 2017
• Subjects: clima valdiviano; anatomía de la madera; dendrocronología; ENSO; pluviosidad; Valdivian climate; wood anatomy; dendrochronology; rainfall; Antarc*; Antarctic
• Online Access: http://revistas.uach.cl/index.php/bosque/article/view/44; https://doi.org/10.4067/S0717-92002016000300003

Tree-ring widths and intrannual wood density fluctuations (IADFs) are sound proxies of the environmental factors that control the growth of forest tree species. In this work we evaluated the impact of climate on radial growth and IADFs formation in an Austrocedrus chilensis plantation in Valdivia, Chile. We calculated mean tree-ring chronology and the annual distribution of IADFs frequency from 20 trees, and we studied their relationships with local precipitation, temperature, and large-scale El Niño-Southern Oscillation (ENSO) and Antarctic Oscillation (AO) climatic teleconnections in the period 1975-2010. We used correlation and multiple linear regression analyses to assess the climate-growth relationships and t test for means comparison to check for differences between years with and without IADFs. We observed an inverse relationship of growth with previous summer precipitation and maximum temperature during the growing period, which suggests physiological stress for trees caused by water surplus and warm summer conditions. Years with maximum IADFs frequency were those coinciding with El Niño events, which caused dry and warm summer conditions in the study area, followed by rainy conditions in September. We did not find statistically significant relationships with AO. The interaction between local climatic conditions and ENSO variation controlled IADFs formation in the wood of A. chilensis in Valdivia. El ancho de los anillos de crecimiento y las fluctuaciones intra-anuales de densidad de la madera (IADF) contienen información sobre los factores ambientales que controlan el desarrollo de las especies forestales. En este trabajo se evaluaron los efectos del clima sobre el crecimiento radial y la formación de IADF en una plantación de Austrocedrus chilensis en Valdivia, Chile. Se calcularon la cronología media de crecimiento radial y la distribución anual de frecuencias de IADF de 20 árboles y se estudió su relación con la precipitación, la temperatura y los índices de El Niño Oscilación del Sur (ENSO) y ...