Tree-ring anomalies of Austrocedrus chilensis from Mediterranean Andes of Chile

ROJAS-BADILLA, M.R.; ÁLVAREZ, C; VELASQUEZ-ÁLVAREZ, G.; HADAD, M.; LE QUESNE, C.; CHRISTIE, D.

Mendoza

Conferencia; Third American Dendrochronology Conference; 2016

Tree Ring Society

Tree-rings anomalies are occurred as marks produced by biotic and abiotic environmental events such as pests, diseases, volcanic eruption, among others, and supply valuable intraseasonal information for study of environmental processes. The objective of this work is describe and quantify the proportion ofthree anomalies in tree-rings from three populations of Austrocedrus chilensis trees along a latitudinal gradient (32°- 35°S). The anomalies studied are missing rings, intra-annual bands and frost rings. The descriptions were performed with samples prepared with standard dendrochronological methodsand photographed with a stereomicroscope (maximum zoom 63x). The results indicate that missing rings are find with major proportion in northernmost population (0.43% from 55,286 rings) and are caused by drought events. The intra-annual bands are most frequent in the middle gradient study site (34°26'S)with 0.36% from 40,494 rings. This anomaly is formed due to drywet events and is characterized by the formation of late wood similar cells inside the ring. Ultimately, frost rings are most frequent in the southern population 0.86% from 27,181 rings. This anomaly is characterized by the formation of lines orclusters of collapsed cells product of water freeze inter and intracells. Of the three anomalies, the only registered with a high proportion were the frost rings. These allow to generate a new line of intra-annual investigation applicable on A. chilensis for further studies of spatial and temporal distribution of anomalies.