Globally, treeline ecotones vary from abrupt lines to extended zones of increasingly small, stunted and/or dispersed trees. These spatial patterns contain information about the processes that control treeline dynamics. Describing these patterns consistently along ecologically meaningful dimensions is needed for generalizing hypotheses and knowledge about controlling processes and expected treeline shifts globally. However, existing spatial categorizations of treelines are very loosely defined, leading to ambiguities in their use and interpretation. To help better understand treeline‐forming processes, we present a new framework for describing alpine treeline ecotones, focusing on hillside‐scale patterns, using pattern dimensions with distinct indicative values: 1) the spatial pattern in the x‐y plane: a) decline in tree cover, and b) change in the level of clustering. Variation along these dimensions results in more or less ‘discrete' or ‘diffuse' treelines with or without islands. These patterns mainly indicate demographic processes: establishment and mortality. 2) Changes in tree stature: a) decline in tree height, and b) change in tree shape. Variation along these dimensions results in more or less ‘abrupt' or ‘gradual' treelines with or without the formation of environmental krummholz. These patterns mainly indicate growth and dieback processes.

中文翻译：

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将高山树木生态交错带模式与基础过程联系起来的全球框架

在全球范围内，林线过渡带从突然的线条到越来越小的，发育不良和/或分散的树木的延伸区域不等。这些空间模式包含有关控制树线动态的过程的信息。为了在全球范围内概括有关控制过程和预期的林木转移的假设和知识，需要沿生态学意义上的维度一致地描述这些模式。但是，现有的树线空间分类定义非常宽松，导致其使用和解释含糊不清。为了帮助更好地理解树线形成过程，我们提出了一个新的框架来描述高山树线过渡带，重点是山坡尺度的格局，使用具有不同指示值的格局维度：1）x-y平面中的空间格局：a）下降在树上，b）聚类水平的变化。沿这些维度的变化会导致带有或不带有岛的或多或少的“离散”或“散布”树线。这些模式主要表明人口统计过程：建立和死亡。2）树形的变化：a）树高下降，b）树形变化。沿这些维度的变化会或多或少地导致“突然的”或“渐进的”树线的形成，无论是否形成环境克鲁姆霍兹。这些模式主要表示增长和消退过程。沿这些维度的变化会或多或少地导致“突然的”或“渐进的”树线的形成，无论是否形成环境克鲁姆霍兹。这些模式主要表示增长和消退过程。沿这些维度的变化会或多或少地导致“突然的”或“渐进的”树线的形成，无论是否形成环境克鲁姆霍兹。这些模式主要表示增长和消退过程。