The genus Juniperus, composed of ca. 76 species, has a broad altitudinal distribution over the northern Hemisphere (Adams 2014). For instance, some juniper shrub species grow in coastal sites (García‐Cervigón et al. 2019) whereas others grow in alpine regions at ˃5,000 m a.s.l. in the Himalayas (Huang et al. 2019, Lu et al. 2019). In the so‐called ‘Third Pole’ region, Juniperus species form some of the highest alpine treelines worldwide (ca. 4,900 m a.s.l.) and survive in harsh environments on poor rocky soils (Miehe et al. 2007, Lyu et al. 2019). Juniperus trees and shrubs at their upper distributional margins (“treeline” and “shrubline”, respectively) likely experience the highest warming rates of all junipers and are recognized as sensitive ecological indicators of responses of land ecosystems to shifting abiotic and biotic conditions (Körner 2012). Accordingly, treelines and shrublines are especially suited for long‐term ecological studies as they are easily relocated over time. However, the upper altitudinal limit of Juniperus and its cause(s) remain unknown.

中文翻译：

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青藏高原上异常高的灌木林

属刺柏，组成CA。76种，在北半球的海拔高度分布广泛（Adams 2014）。例如，一些杜松灌木树种生长在沿海地区（García-Cervigón等人，2019），而其他一些生长在喜马拉雅山海拔5,000 m的高海拔地区（Huang等人，2019; Lu等人，2019）。在所谓的``第三极''地区，杜松属物种构成了世界上一些最高的高山林线（大约4,900 m asl），并在恶劣的岩石土壤上的恶劣环境中生存（Miehe等人2007，Lyu等人2019）。 。杜松属处于较高分布边缘的树木和灌木（分别为“ treeline”和“灌木线”）可能经历所有杜松的最高升温速率，并被认为是土地生态系统对非生物和生物条件变化的响应的敏感生态指标（Körner2012） 。因此，树线和灌木线特别适合于长期生态研究，因为它们很容易随时间推移而重新定位。然而，杜松的最高海拔上限及其原因仍然未知。