Kharuk Viacheslav I, Im Sergey T, Petrov Ilya A, Golyukov Alexei S, Ranson Kenneth J, Yagunov Mikhail N
Sukachev Institute of Forest, 660036, Krasnoyarsk, Russia.
Siberian Federal University, 660041, Krasnoyarsk, Russia.
For Ecol Manage. 2017 Jan 15;384:191-199. doi: 10.1016/j.foreco.2016.10.050. Epub 2016 Oct 27.
Siberian pine () and fir () (so called "dark needle conifers", DNC) showed decreased radial growth increment within the Lake Baikal watershed since the 1980s with increasing mortality recorded since the year 2000. Tree ring width was strongly correlated with vapor pressure deficit, aridity and root zone moisture. Water stress from droughts made trees more susceptible to insect attacks causing mortality in about 10% of DNC stands within the Lake Baikal watershed. Within Siberia DNC mortality increased in the southern part of the DNC range. Biogeographically, tree mortality was located within the DNC - forest-steppes transition. Tree mortality was significantly correlated with drought and soil moisture anomalies. Within the interior of the DNC range mortality occurred within relief features with high water stress risk (i.e., steep convex south facing slopes with shallow well-drained soils). In general, DNC mortality in Siberia was induced by increased aridity and severe drought (inciting factors) in synergy with biotic attacks (contributing factor). In future climate scenarios with predicted increase in aridity DNC could be eliminated from the southern part of its current range and will be replaced by drought-resistant conifers and broadleaf species (e.g., , and ).
自20世纪80年代以来，西伯利亚松（）和冷杉（）（即所谓的“暗针叶针叶树”，DNC）在贝加尔湖流域内的径向生长增量下降，自2000年以来记录的死亡率不断上升。年轮宽度与蒸气压亏缺、干旱和根区湿度密切相关。干旱造成的水分胁迫使树木更容易受到昆虫攻击，导致贝加尔湖流域内约10%的DNC林分死亡。在西伯利亚，DNC死亡率在其分布范围的南部有所增加。从生物地理学角度来看，树木死亡发生在DNC-森林草原过渡带内。树木死亡率与干旱和土壤湿度异常显著相关。在DNC分布范围的内部，死亡发生在具有高水分胁迫风险的地形特征内（即朝南的陡峭凸坡，土壤排水良好且浅薄）。总体而言，西伯利亚的DNC死亡是由干旱加剧和严重干旱（诱发因素）与生物攻击（促成因素）协同作用导致的。在未来干旱预计增加的气候情景下，DNC可能会从其当前分布范围的南部消失，并将被耐旱针叶树和阔叶树种（如、和）所取代。
