Regional chronologies of Cedrela fissilis and Cedrela angustifolia in three forest types and their relation to climate

KATHELYN PAREDES-VILLANUEVA; LIDIO LOPEZ; RAFAEL MARIA NAVARRO CERRILLO

TREES-STRUCTURE AND FUNCTION

SPRINGER

Lugar: Berlin; Año: 2016

0931-1890

Cedrela species are highly valued because of the quality of their timber. Understanding the behaviour of each different Cedrela species and their ecology is of importance to ensuring that forest harvesting and management do not endanger the survival of natural populations. These species grow in a wide range of environmental gradients and different types of forests in Bolivia. Thisstudy used dendrochronological methods to analyse growth?precipitation relationships of two Cedrela species coming from three locations with different environmental conditions: dry Chiquitano (Concepcio´n), Chiquitanotransitional Amazonian (Guarayos), and Bolivian-Tucuman montane forests (Postrervalle). The rainy season in all locations runs from October to April and the dry season runs from May to September. Twelve Cedrela fissilis specimens were sampled from dry Chiquitano, 11 Cedrela fissilis specimens from Chiquitano transitional Amazonian, and 30 Cedrela angustifolia specimens from Bolivian-Tucuman montane forests. The samples were crossdated and exhibited a common signal between trees from three sites, despite tree rings from the Chiquitano transitional Amazonian forest being narrower and displaying blurred bandsof parenchyma in the boundaries. Significant inter-series correlation was found for the C. fissilis species series from dry Chiquitano with r = 0.261 (p�.01) and Chiquitano transitional Amazonian forests with r = 0.284 (p�.01),and for Cedrela angustifolia from Bolivian-Tucuman montane forests with r = 0.374 (p�.01). Mean annual growth was 2.07, 1.92, and 2.82 mm year-1 at the three sites, respectively. Cedrela species from dry Chiquitano and Bolivian-Tucuman montane forests were sensitive to precipitation from October to April of the current growth year (wettest season) and to low temperatures from May toJuly of the current growth year (driest season). Samples from Chiquitano transitional Amazonian were more sensitive to precipitation during late rainy season (March, April, and May of the current growth year) and high temperaturesduring the rainy months (November?December). Growth differences between sites and species in response to climate variations and local conditions should be taken into account and handled with different forest management guidelines