Publication Type:Journal Article
Source:Forest Ecology and Management, Volume 109, Number 1-3, p.261 - 269 (1998)
Keywords:Decline, incidence, Saturated soil, Slope gradient
Decline and mortality of Austrocedrus chilensis occurs throughout its natural distribution in Argentina. The problem was noted several decades ago but its causes are unknown. The aim of this work is to investigate the association between the occurrence of the decline and site characteristics considered to be relevant from the ecological point of view. A multivariate analysis is carried out using topographic and climatic information, obtained from 32 sites, within the limits of the Nahuel Huapi National Park, showing a wide range of decline and mortality incidence. Results of this study suggest that an ecological pattern of tree decline and mortality exists. The A. chilensis forests seem more prone to developing symptoms when occurring at sites with higher precipitation and not very high altitudes. To the eastern limit of its distribution, where precipitation is substantially low, A. chilensis forests show no symptoms of decline. It is, thus, hypothesized that sites with relatively poor soil drainage are more prone to develop symptoms. However, it is not clear whether high soil moisture directly affects roots or it produces a more suitable environment for root pathogen proliferation and infection.