ORIGINAL ARTICLE Annual and intra-annual growth dynamics of Myricaria elegans shrubs in arid Himalaya Jiri Dolezal 1,2 • Eliska Leheckova 1,2 • Kristina Sohar 1 • Miroslav Dvorsky 1 • Martin Kopecky 1 • Zuzana Chlumska 2 • Jan Wild 1 • Jan Altman 1 Received: 22 April 2015 / Revised: 9 October 2015 / Accepted: 13 October 2015 / Published online: 30 October 2015 Ó Springer-Verlag Berlin Heidelberg 2015 Abstract Key message To disentangle complex drivers of Myri- caria elegans growth in arid Himalaya, we combined tree-ring analysis with detailed dendrometer records. We found that the combination of winter frost, summer floods, and strong summer diurnal temperature fluctu- ations control annual and intra-annual growth dynamics. The relative importance of these drivers is, however, changing with ongoing climate change. Abstract High-mountain areas are among the most sen- sitive environments to climate change. Understanding how different organisms cope with ongoing climate change is now a major topic in the ecology of cold environments. Here, we investigate climate drivers of the annual and intra-annual growth dynamics of Myricaria elegans,a 3–6 m tall tree/shrub, in a high-elevation cold desert in Ladakh, a rapidly warming region in the NW Himalayas. As Myricaria forms narrow stands around glacier streams surrounded by the desert, we hypothesized that its growth between 3800 and 4100 m will be primarily limited by low temperatures and summer floods. We found that warmer and less snowy conditions in April and May enhance earlywood production. Latewood formation is mostly driven by the June–July temperatures (T). The positive effect of warmer summers on both annual and intra-annual growth is related to fluctuating daily T (from ?30 to 0 °C). In particular, dendrometer measurements over a 2-year period showed that net daily growth incre- ments increased when the summer night T remained above 6 °C. While high night T during generally cold desert nights promoted growth, high daytime T caused water stress and growth inhibition. The growth–temperature dependency has gradually weakened due to accelerated warming since the 1990s. In addition, positive latewood responses to high March precipitation during the colder 1960s–1980s have become negative during the warmer 1990s–2000s, reflecting an intensification of summer floods. Latewood width increased while earlywood width decreased from the 1990s, indicating a prolonged growing season and a higher risk of drought-induced embolism in earlywood vessels. Due to a multiplicity of environmental drivers including winter frost, intensified floods and strong summer diurnal T fluctuations, Myricaria growth is not controlled by a single climate parameter. Similar results are increasingly reported from other Himalayan treelines, showing that ongoing climate change will trigger complex and probably spatially variable responses in tree growth. Our study showed that these complex climatic signals can be disentangled by a combination of long-term data from tree-rings with detailed, but short-term, records from dendrometers. Keywords Climate–growth relationship Á Flooding Á Tree-rings Á Dendrometer Á Diurnal radius variation Á Himalaya Á Intra-annual growth Á Pointer years Á Global warming Communicated by E. Liang. Electronic supplementary material The online version of this article (doi:10.1007/s00468-015-1318-9) contains supplementary material, which is available to authorized users. & Jiri Dolezal jiriddolezal@gmail.com 1 Institute of Botany, The Czech Academy of Sciences, Za ´mek 1, 252 43 Pru ˚honice, Czech Republic 2 Department of Botany, Faculty of Science, University of South Bohemia, Na Zlate ´ stoce 1, 370 05 C ˇ eske ´ Bude ˇjovice, Czech Republic 123 Trees (2016) 30:761–773 DOI 10.1007/s00468-015-1318-9