Effects of decadal experimental drought and climate extremes on vegetation growth in Mediterranean forests and shrublands

Increased drought combined with extreme episodes of heatwaves is triggering severe impacts on vegetation growth, particularly for plant communities in arid and semiarid ecosystems. Although there is an abundance of short-term field drought experiments in natural ecosystems, remaining knowledge gaps...

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Detalles Bibliográficos
Autores: Liu, Daijun|||0000-0002-0993-0832, Zhang, Chao|||0000-0001-6009-9450, Ogaya Inurrigarro, Romà|||0000-0003-4927-8479, Estiarte, Marc|||0000-0003-1176-8480, Peñuelas, Josep|||0000-0002-7215-0150
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:232637
Acceso en línea:https://ddd.uab.cat/record/232637
https://dx.doi.org/urn:doi:10.1111/jvs.12902
Access Level:acceso abierto
Palabra clave:Ground biomass increment
Decadal drought experiment
Habitat context
Mediterranean ecosystems
Standing density
Vegetation growth
Descripción
Sumario:Increased drought combined with extreme episodes of heatwaves is triggering severe impacts on vegetation growth, particularly for plant communities in arid and semiarid ecosystems. Although there is an abundance of short-term field drought experiments in natural ecosystems, remaining knowledge gaps limit the understanding and prediction of vegetation growth to ongoing and future climate scenarios. Here, we assessed the impacts of long-term (1999-2016) experimental drought (ca. -30% rainfall) on the vegetation growth of a Mediterranean high (H) and low (L)-canopy forests and an early-successional shrubland, as indicated by above-ground biomass increment (ABI) and standing density, respectively. We found habitat context (impact of historical climate change, soil depth and successional status) of the study sites significantly affected the magnitude of climate impacts; there were synergistic effects of experimental drought and meteorological drought (Standardised Precipitation-Evapotranspiration Index, SPEI) as well as extreme dry years on vegetation growth. Long-term experimental drought decreased the ABI for the two forest canopy types and the standing density for the shrubland. Water availabilities in winter-spring (SPEIs) were positively correlated with the ABI and standing density. Moreover, experimental drought decreased the vegetation growth in extreme dry years for the shrubland. We propose that future work not only study the vegetation dynamics with physiological, phenological and demographical changes in long-term processes and across climate gradients, but also should explore the changes of multiple functions simultaneously (e.g. multifunctionality) under long-term processes and extremes. This type of analysis of long-term data is essential to understand and predict biodiversity loss, composition shifts, declines in ecosystem function and carbon budgets at temporal and spatial scales, to enable policy makers to design and implement strategies for the maintenance of sustainable ecosystem function under future climate change scenarios.