Format: ORAL

Jaime Purtolas1*, gueda M. Gonzlez-Rodrguez1, Alicia Perera-Castro1, Yauci Espinosa-Gonzlez1, Celine I. Garca-Rodrguez1, Beatriz Fernndez-Marn2

1. Department of Botany, Ecology, and Plant Physiology, Universidad de La Laguna, La Laguna, Spain 2. Department of Plant Biology and Ecology, Universidad del País Vasco, Leioa, Spain * Presenting author. jpuertol@ull.edu.es

Precipitation reduction and increasing temperatures are impacting plant communities of the Macaronesian region. Hence, tools for evaluation and classification of plant species according to their vulnerability to increasing air and soil dryness are needed for plant conservation. Ecophysiological studies focused on a single or small group of species provide important information for this goal, but studies on adaptive ecophysiological trait syndromes could quantitative and qualitative improve our capacity to classify species according to their drought resistance. In this study, we measured physiological leaf traits related to drought resistance in more than 70 vascular species distributed across the four National Parks in the Canary Islands. The biomes represented in these NPs comprises a very strong climatic gradient within the generally Mediterranean-type climate, especially in terms of water availability, from the arid climate of Timanfaya to the cloud forests of Garajonay, and from the typical Mediterranean climate of the pine forest in Caldera de Taburiente to the alpine dry environment of Mount Teide and the summits of La Caldera de Taburiente. Leaf traits comprised both drought tolerance (leaf rehydration capacity after dehydration, leaf functionality after dehydration, water potential at full turgor) and avoidance traits (leaf hydraulic conductance, minimal leaf conductance, vein and stomatal density, leaf water absorption capacity and hydrophobicity). In addition, climatic data from the last 20 years recorded by the large weather station network located within the four NPs was compiled to calculate drought indices. Trait average values per species was related to climatic data with multivariate statistical tools aimed to establish groups of species and traits and establish relationships with climatic aridity. The results allowed identifying different trait combinations (syndromes) and their variation along the climatic aridity gradient. We classified the studied species based on those syndromes, thus defining strategies and overall predicted capacity to resist drought.