Climate threats on growth of rear-edge European beech peripheral populations in Spain
Dorado-Liñán, I. ; Akhmetzyanov, L. ; Menzel, A. - \ 2017
International Journal of Biometeorology 61 (2017)12. - ISSN 0020-7128 - p. 2097 - 2110.
Climate change - European beech - Peripheral populations - Rear edge - Tree growth
European beech (Fagus sylvatica L.) forests in the Iberian Peninsula are a clear example of a temperate forest tree species at the rear edge of its large distribution area in Europe. The expected drier and warmer climate may alter tree growth and species distribution. Consequently, the peripheral populations will most likely be the most threatened ones. Four peripheral beech forests in the Iberian Peninsula were studied in order to assess the climate factors influencing tree growth for the last six decades. The analyses included an individual tree approach in order to detect not only the changes in the sensitivity to climate but also the potential size-mediated sensitivity to climate. Our results revealed a dominant influence of previous and current year summer on tree growth during the last six decades, although the analysis in two equally long periods unveiled changes and shifts in tree sensitivity to climate. The individual tree approach showed that those changes in tree response to climate are not size dependent in most of the cases. We observed a reduced negative effect of warmer winter temperatures at some sites and a generalized increased influence of previous year climatic conditions on current year tree growth. These results highlight the crucial role played by carryover effects and stored carbohydrates for future tree growth and species persistence.
Influence of climate drivers and the North Atlantic oscillation on beech growth at marginal sites across the mediterranean
Chen, K. ; Dorado-Liñán, I. ; Akhmetzyanov, L. ; Gea-Izquierdo, G. ; Zlatanov, T. ; Menzel, A. - \ 2015
Climate Research 66 (2015)3. - ISSN 0936-577X - p. 229 - 242.
European beech - Fagus sylvatica - Mediterranean basin - North atlantic oscillation - Summer drought - Tree rings
European beech Fagus sylvatica L. represents one of the most commercially and ecologically important forest tree species in Europe. The study of climate-growth relationships may provide relevant information to assist projections of future species' distribution as well as forest management strategies. In this study, 9 European beech stands were selected at the rear edges of the species' distribution across an east-west gradient in the Mediterranean Basin (MB).Most of the tree-ring chronologies reached back more than a century; however we investigated the common period 1950-2012 in order to avoid past intensive management activities at some sites. The influences of temperature and precipitation on tree growth as well as their geographical patterns were investigated. Furthermore, the influence of the dominant atmospheric circulation pattern, the North AtlanticOscillation (NAO), was also assessed. The results reveal that tree growth in stands located in the western MB are limited by the combined influences of summer temperature and precipitation while stands located in central and eastern MB are mainly limited by summer temperature and show consistent lag effects on growth. The dry conditions prevailing during positive phases of the winter NAO have exerted a significant negative influence at sites located in western and central MB for the last 6 decades. However, the significance of NAO influence has generally decreased from western to eastern MB during recent decades. The results also provide evidence for the existence of carry-over effects that may be essential for the persistence and survival of some of these marginal populations.