CONICET | Buscador de Institutos y Recursos Humanos

The width of tree-rings is the anatomical trait that traditionally is used in dendrochronology. Nevertheless, the use of anatomical variables may improve dendrochronological interpretation of environmental problems. The precise chronological reading of these variables in the wood of trees provides the bases for improving our knowledge about seasonal changes in the anatomical properties of wood and consequently the derivation of climatic information from these characteristics. In this work we report the development of chronologies based on the width of tree-rings, total area of vessels and the number of vessels per tree-ring of the Prosopis flexuosa wood samples from the xerophytic woodlands of central Argentina. Due to the particular characteristics which present the anatomy of wood of P.flexuosa, the identification of the vessels elements is difficult, from what different methodologies were carried out to obtain the chronologies of vessels. The width of the rings, the number of vessels, and the total area of vessels were positively influenced by regional precipitation during November and December, which reflects the importance of the water availability in the initial stage of the formation of the wood. The width of the rings and the total area of vessels were negatively influenced by temperature during the same months, while the number of vessels was not significantly correlated with temperature. The high temperatures in spring increase evapotranspiration, which reduces water availability to plants and results in an inverse growth response. This study was the first to development chronologies based on anatomic characters of woods from the arid and semiarid regions of South America and with significant applications in ecological and climatic studies.