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Strategies shrubby junipers adopt to tolerate drought differ by site

Drought-induced dieback episodes are globally reported among forest ecosystems but they have been understudied in scrublands. Chronically-stressed individuals are supposed to be more vulnerable prior to drought which triggers death. Drought-triggered dieback and mortality events affecting Mediterranean Juniperus phoenicea scrublands were analyzed in two sites with contrasting climate and soil conditions located in Spain. The radial growth patterns of coexisting living and dead junipers, including the calculation of growth statistics used as early-warning signals, quantified growth response to climate, were characterized and the wood C and O isotope discrimination was analyzed. In the inland, continental site with rocky substrates (Yaso, Huesca, N Spain), dead junipers grew less than living junipers about three decades prior to the dieback started in 2016. However, in the coastal, mild site with sandy soils (Doñana, Huelva, SW Spain), dead junipers were smaller but grew more than living junipers about two decades before the dieback onset in 2005. The only common patterns between sites were the higher growth coherence in both living and dead junipers prior to the dieback, and the decrease in growth persistence of dead junipers. Cool and wet conditions in the prior winter and current spring, and cool summer conditions enhanced juniper growth. In Doñana, growth of living individuals was more reduced by warm July conditions than in the case of dead individuals. Higher ?13C values in Yaso indicate also more pronounced drought stress. In Yaso, dead junipers presented lower ?18O values, but the opposite occurred in Doñana suggesting different changes in stomatal conductance prior to death. Warm summer conditions enhance evapotranspiration rates and trigger dieback in this shallow-rooted species, particularly in sites with a poor water-holding capacity. Chronic, slow growth is not always a reliable predictor of drought-triggered mortality. informacion[at]ebd.csic.es: Camarero et al (2020) Dieback and mortality of junipers caused by drought: Dissimilar growth and wood isotope patterns preceding shrub death. Agr Forest Meteorol 291, 108078. DOI 10.1016/j.agrformet.2020.108078


https://www.sciencedirect.com/science/article/pii/S0168192320301805?dgcid=author#ack0001
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Highly Cited Researchers 2018

Highly Cited Researchers 2018

Our colleagues Montserrat Vilà and Pedro Jordano appear in the 2018 list of Highly Cited Researchers published this week by Clarivate Analytics. Montse is included in the Category Environment/Ecology and Pedro in the "Cross-field" Category. This is an annual list recognizing influential researchers from around the world. The 2018 list contains 6078 Highly Cited Researchers, 4058 in 21 fields of the sciences and social sciences and 2020 Highly Cited Researchers are identified as having exceptional performance across several fields. For the 2018 Highly Cited Researchers analysis, the papers surveyed were those published and cited during 2006-2016. To identify researchers with Cross-Field impact, highly cited paper and citations are normalized between fields and summed. The list includes 119 researchers working in Spain, 23 from CSIC. Five Spanish researchers appear in the Environment/Ecology area (out of 185) and 41 are classified as "cross field" researchers. Congratulations! 


https://hcr.clarivate.com/