Article Climate Change-Induced Shift of Tree Growth Sensitivity at a Central Himalayan Treeline Ecotone Niels Schwab 1,* ID , Ryszard J. Kaczka 2 ID , Karolina Janecka 3, Jürgen Böhner 1, Ram P. Chaudhary 4, Thomas Scholten 5 and Udo Schickhoff 1 1 Physical Geography, Center for Earth System Research and Sustainability (CEN), University of Hamburg, 20146 Hamburg, Germany;
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[email protected] (U.S.) 2 Faculty of Earth Sciences, University of Silesia in Katowice, 41-200 Sosnowiec, Poland;
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[email protected]; Tel.: +49-40-42838-5929 Received: 4 April 2018; Accepted: 10 May 2018; Published: 13 May 2018 Abstract: Himalayan treelines are exposed to above average climate change impact, resulting in complex tree growth–climate relationships for Himalayan Silver Fir (Abies spectabilis (D. Don) Spach) at central Himalayan treelines. The majority of recent studies detected current tree growth sensitivity to dry conditions during pre-monsoon seasons. The aim of this study was to analyze growth–climate relationships for more than a century for a treeline ecotone in east-central Nepal and to test for Blue Intensity (BI; used as a surrogate of maximum late wood density) as climate proxy.