Warming-induced shrubline advance stalled by moisture limitation on the Tibetan Plateau

Willows (Salix) are some of the most abundant shrubs in cold alpine and tundra biomes. In alpine regions, seed dispersal is not limiting upwards willow expansion, so the upslope shift of willow shrublines is assumed to be a response to climatic warming. Very little, however, is known about the recen...

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Detalles Bibliográficos
Autores: Wang, Yafeng|||0000-0003-2656-3605, Liang, Eryuan|||0000-0002-8003-4264, Lu, Xiaoming|||0000-0002-5012-9270, Camarero, Jesús Julio|||0000-0003-2436-2922, Babst, Flurin|||0000-0003-4106-7087, Shen, Miaogen|||0000-0001-5742-8807, Peñuelas, Josep|||0000-0002-7215-0150
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:299971
Acceso en línea:https://ddd.uab.cat/record/299971
https://dx.doi.org/urn:doi:10.1111/ecog.05845
Access Level:acceso abierto
Palabra clave:Alpine shrubline
Global warming
Moisture limitation
Shrub expansion
Tibetan Plateau
Descripción
Sumario:Willows (Salix) are some of the most abundant shrubs in cold alpine and tundra biomes. In alpine regions, seed dispersal is not limiting upwards willow expansion, so the upslope shift of willow shrublines is assumed to be a response to climatic warming. Very little, however, is known about the recent spatiotemporal dynamics of alpine willow shrublines. The world's highest willow shrublines (ca 4900 m a.s.l.) are located on the Tibetan Plateau (TP) and provide a rare opportunity to test their sensitivity and responses to rapid warming and the associated increase in the demand for water in ecosystems. We used a new data set comprising 24 Salix shrubline plots along a 900-km latitudinal gradient (30‒38°N) to reconstruct the rates of annual shrub recruitment and shifting shrubline positions since 1939. Shrub densification and shrubline advances were promoted by pronounced summer warming before 2010, contributing to widespread greening on the TP. These trends, however, reversed due to warming-induced moisture limitation after 2010, which thus represented a tipping point of warming/drying trade-offs. Climatic warming and drying are predicted to accelerate in the following decades, so alpine plant communities may be at an increasing risk of population decline or even range contraction.