Warming induced changes in wood matter accumulation in tracheid walls of spruce

作     者：Elena BABUSHKINA Dina ZHIRNOVA Liliana BELOKOPYTOVA Eugene VAGANOV Elena BABUSHKINA;Dina ZHIRNOVA;Liliana BELOKOPYrOVA;Eugene VAGANOV

作者机构：Khakass Technical InstituteSiberian Federal UniversityAbakan655017Russia Siberian Federal UniversityKrasnoyarsk 660041Russia Sukachevlnstitute of ForestSiberian Branch of Russian Academy of SciencesKrasnoyarsk 660036Russia 

出 版 物：《Journal of Mountain Science》 (山地科学学报（英文）)

年 卷 期：2020年第17卷第1期

页      面：16-30页

核心收录：

学科分类：07[理学] 0713[理学-生态学] 

基　　金：funded by the Russian Foundation for Basic Research (Project No. 17-04-00315, data aquisition and wood anatomy analysis) Russian Science Foundation (Project No 19-18-00145, analysis of climate change and its impact) 

主　　题：Climate change Sayano-Shushenskoe Reservoir Elevational gradient Picea obovata Quantitative wood anatomy Climate–growth relationship 

摘      要：The warming-driven increase of the vegetation season length impacts both net productivity and phenology of plants, changing an annual carbon cycle of terrestrial ecosystems. To evaluate this influence, tree growth along the temperature gradients can be investigated on various organization levels, beginning from detailed climatic records in xylem cells’ number and morphometric parameters. In this study, the Borus Ridge of the Western Sayan Mountains(South Siberia) was considered as a forest area under rapid climate change caused by massive Sayano-Shushenskoe reservoir. Several parameters of the xylem anatomical structure in Siberian spruce(Picea obovata Ledeb.)were derived from normalized tracheidograms of cell radial diameter and cell wall thickness and analyzed during 50 years across elevational gradient(at 520,960, and 1320 m a.s.l.). On the regional scale, the main warming by 0.42°C per decade occurs during cold period(November–March). Construction of the reservoir accelerated local warming substantially since 1980, when abrupt shift of the cold season temperature by 2.6°C occurred. It led to the vegetation season beginning 3-6 days earlier and ending 4-10 day later with more stable summer heat supply. Two spatial patterns were found in climatic response of maximal cell wall thickness:(1)temperature has maximal impact during 21-day period, and its seasonality shifts with elevation in tune with temperature gradient;(2) response to the date of temperature passing +9.5°C threshold is observed at two higher sites. Climate change yielded significantly bigger early wood spruce tracheids at all sites, but its impact on cell wall deposition process had elevational gradient: maximal wall thickness increased by 7.9% at the treeline, by 18.2% mid-range,and decreased by 4.9% at the lower boundary of spruce growth;normalized total cell wall area increased by 6.2%-6.8% at two higher sites but remained stable at the lowest one. We believe that these patterns are caused by two m