New article: Understory light predictions in mixed conifer mountain forests

In a new article published in the journal Forest Ecology and Management, members of FiDBosc, led by Aitor Ameztegui, have highlighted the importance of explicitly considering aspect when modeling the dynamics of mountain forests.

Predicting light availability in forest understory is a key step in the modeling of forest dynamics. In mountain forests, aspect is often the main source of environmental variation, and so aspect-induced differences in crown geometry and transparency can sharply affect light transmission through the canopy and modify understory light predictions. However, this effect has almost been ignored to date. 

This study, in which we collaborated with researchers from the Université du Québec à Montreal (UQÀM) and the  Spanish National Research Council (CSIC), has shown that the effect of slope aspect on tree crowns is highly species-specific. Aspect influences crown geometry, transparency and irregularity of all the studied species (silver fir, Scots pine and mountain pine), and therefore the observed changes in crown openness may be a combined effect of changes in total leaf area and patterns of leaf distribution. The observed species-specific variation in crown geometry and openness with aspect resulted in sharp differences in understory light predictions that were large enough to warrant explicit consideration when studying and modeling the ecological processes driving the dynamics of these forests.

Ameztegui, A, Coll, L, Benavides, R, Valladares, F, & Paquette, A (2012). Understory light predictions in conifer-mixed forests: the role of aspect-induced variation in crown geometry and openness Forest Ecology and Management, 276 (52-61) DOI: 10.1016/j.foreco.2012.03.021