Simulations of Growth and Drought-Induced Effects in Andean Cypress-Coihue Mixed Forests

Abstract

Andean cypress (Austrocedrus chilensis) and coihue (Nothofagus dombeyi) growin potentially wood-productive mixed forests, but the design of forest management schemes is still necessary. These forests have experienced extreme drought,which will be more frequent in the future. This work aimed to evaluate the coihueAndean cypress mixed forests estimated growth under different forest structures,using LAI (leaf area index) as an occupied growing space indicator, and to evaluate predicted stand growth losses induced by drought events. We fitted LAI-volumeperiodic annual increment (VPAI) models and applied them to different theoreticalLAI arrangements to design target stands. We also simulated 3 drought scenariosand determined the consequences for stand growth for three target stands. If coihue is favored in the upper stratum and Andean cypress in the lower stratum, standVPAI may be high. Drought losses may result in 40–50% coihue growth reduction.This species could maintain higher production than the Andean cypress even undermedium impact. Promoting a balanced species composition, with a slightly greaterstocking of coihue in the upper stratum and relegating Andean cypress to the lowerstratum, would seem to be a compromise between production and adaptation toextreme drought events.