Subtropical dendroecology: dating disturbances and forest dynamics in northwestern Argentina montane ecosystems

Abstract

The use of dendroecological techniques to describe temporal patterns of disturbances and forest dynamics has been largely restricted to high-latitude ecosystems. In this review, we present the results of recent developments in subtropical northwestern Argentina (22–28°S). The area is characterized by a subtropical monsoonal climate (wet summers, dry winters) which implies that some species respond to climatic seasonality by producing annual tree rings. Alnus acuminata, a deciduous species that dominates the upper montane forests (1700–2700 m), has been successfully used to describe patterns of forest regeneration, fire, landslides, and floods by dating scars, establishment events and changes in growth patterns and to relate these patterns with climate and land use during the twentieth century. Establishment dates, growth releases, and resprout dates of species with annual tree rings (e.g. Cedrela lilloi, Solanum riparium, Cinammomum porphyria) have been used in lower montane forests to describe regeneration dynamics in relation to treefall gaps. These results indicate that dendroecology is a feasible and promising research line that needs further exploration in this geographical area. Among the research priorities we identified are: (1) exploration of the use of these species in forests of lower latitudes (e.g. southern Peru and Bolivia), (2) increase of sample sizes and target species, in order to extend the temporal and spatial domains of these studies, (3) explore the use of other species in the same area to study other ecological processes or the same ones in different environments.