Uniform climate sensitivity in tree-ring stable isotopes across species and sites in a mid-latitude temperate forest

摘要: Tree-ring stable isotopes, providing insight into drought-induced eco-physiological mechanisms, are frequently used to reconstruct past changes in growing season temperature and precipitation. Their climatic response is, however, still not fully understood, particularly for data originating from non-extreme, mid-latitude environments with differing ecological conditions. Here, we assess the of δ(13)C, δ(18)O tree-ring width (TRW) a temperate mountain forest Austrian pre-Alps climate specific drought events. Variations stem growth isotopic composition Norway spruce, common beech European larch dry, medium moist sites compared records sunshine, temperature, moisture, precipitation cloud cover. Results indicate uniform year-to-year variations δ(13)C across species, but distinct differences TRW according habitat species. While sensitivity is overall weak, chronologies contain significant signals maximum cover (r = -0.72 δ(18)O). The coherent inter-annual accompanied by substantial signatures offsets up ∼3‰ indicating species-specific physiological strategies varying water-use efficiencies. During severe summer drought, benefit access deeper soils, allowing them keep their stomata open. This strategy an increased water loss through transpiration, simultaneously enables enhanced photosynthesis. Our findings potential isotopes forests cover, improve knowledge on basic mechanisms tree species different habitats cope soil moisture deficits.