Problems with edges: Tree lines as indicators of climate change (or not)

Abstract

Elevational tree lines are commonly seen as particularly important ecological 'ecotones' that should, according to models, respond sensitively to climate change. In this issue, Mathisen et al. report empirical analyses of two tree lines that fail to show expected upward movement. This study points up both methodological and conceptual challenges in understanding ecological edges and in connecting general expectations to specific cases. Elevational treelines are commonly seen as particularly important ecological 'ecotones' that should, according to models, respond sensitively to climate change. In this issue, Mathisen et al. report empirical analyses of two treelines that fail to show expected upward movement. This study points up both methodological and conceptual challenges in understanding ecological edges and in connecting general expectations to specific cases. copy; 2013 International Association for Vegetation Science.