1211 | 711 | Exploring the resilience of Iberian holm oak woodlands to extreme droughts using large-scale remote sensing analysis | Mariano Moreno-de-las-Heras (1); Esther Bochet (2); Sergio M. Vicente-Serrano (3); Tiscar Espigares (4); Maria José Molina (2); Vicente Monleón (5); José Manuel Nicolau (6, 7); Jaume Tormo (6, 7); Patricio García-Fayos (2).
The organization and function of forest ecosystems are changing at an unprecedent rate under the influence of climate change and human uses. In this context of change, the increasing frequency, intensity and duration of droughts that affect the Mediterranean basin urges evaluation of forest vulnerability to drought and their effects for the long-term stability of forest ecosystems. We explore the responses and factors that control the resilience of holm oak (Quercus ilex) woodlands to recent extreme droughts during 2000-2019 in a broad climate aridity gradient that extends from sub-humid to semi-arid conditions across a 100,000 km2 region in eastern Spain, using a remote sensing approach. Our results show that climate aridity and forest structure largely control the resistance, recovery and resilience of holm oak woodlands to drought, and these responses are also affected by drought intensity and both pre- and post-drought hydric conditions. Q. ilex woodlands located in the dry edge of the explored aridity gradient showed a high sensitivity to extreme drought. Their resistance, assessed as the capacity of the woodlands to maintain primary production during drought, was low. In addition, they showed poor resilience, characterized by low capacity to fully recover to their pre-drought production levels. Contrarily, holm oak woodlands in sub-humid areas of the study region, where wetter climate conditions may alleviate water stress during dry periods, showed a high resistance and resilience to drought. Drought vulnerability was particularly high for dense holm oak stands under semi-arid climate conditions, where strong competition for scarce water resources largely increased the negative effects of extreme drought. These results demonstrate the value of our remote sensing approach for monitoring drought vulnerability of forest ecosystems. We also discuss the implications of these results for the management of Q. ilex forests in the present context of climate change.
Mariano Moreno-de-las-Heras (1); Esther Bochet (2); Sergio M. Vicente-Serrano (3); Tiscar Espigares (4); Maria José Molina (2); Vicente Monleón (5); José Manuel Nicolau (6, 7); Jaume Tormo (6, 7); Patricio García-Fayos (2).
(1) Department of Geography, University of Barcelona, 08001 Barcelona, Spain; (2) Desertification Research Center (CIDE, CSIC-UV-GV), 46113 Moncada (Valencia), Spain; (3) Pyrenean Institute of Ecology (IPE-CSIC), Spanish National Research Council (CSIC), 50059 Zaragoza, Spain; (4) Department of Life Sciences, University of Alcalá, 28871 Alcalá de Henares (Madrid), Spain; (5) US Forest Service Pacific Northwest Research Station, Corvallis, Oregon 97331, USA; (6) Department of Agrarian and Environmental Sciences, University of Zaragoza, 22071 Huesca, Spain; (7) Environmental Sciences Institute of Aragon, University of Zaragoza, 50009 Zaragoza, Spain.
ID Abstract: 711