Warming climate and resulting declines in seasonal snowpack have been associated with drought stress and tree mortality in seasonally snow‐covered watersheds worldwide. Meanwhile, increasing forest density has further exacerbated drought stress due to intensified tree–tree competition. Using a uniquely detailed data set of population‐level forest growth (n = 2,495 sampled trees), we examined how inter‐annual variability in growth relates to snow volume across a range of forest densities (e.g., competitive environments) in sites spanning a broad aridity gradient across the United States. Forest growth was positively related to snowpack in water‐limited forests located at low latitude, and this relationship was intensified by forest density. However, forest growth was negatively related to snowpack in a higher latitude more energy‐limited forest, and this relationship did not interact with forest density. Future reductions in snowpack may have contrasting consequences, as growth may respond positively in energy‐limited forests and negatively in water‐limited forests; however, these declines may be mitigated by reducing stand density through forest thinning.

中文翻译：

---

森林密度增加了积雪对缺水松树林生长的重要性。

气候变暖以及由此导致的季节性积雪减少与全球季节性积雪流域的干旱压力和树木死亡有关。同时，由于树木竞争加剧，森林密度的增加进一步加剧了干旱压力。使用唯一详细的人口级森林生长数据集（n = 2,495采样树木），我们研究如何变化，且年际增长涉及到雪量在一系列横跨在全美广泛的干旱梯度网站森林密度（如竞争环境）的。在低纬度的缺水森林中，森林的生长与积雪成正相关，而森林密度则加剧了这种关系。但是，在高纬度，能源有限的较高森林中，森林的生长与积雪负相关，并且这种关系与森林密度无关。未来减少积雪可能会产生相反的结果，因为能源有限的森林的增长可能会产生积极反应，而水资源有限的森林可能会产生负面影响；但是，可以通过森林砍伐降低林分密度来缓解这些下降。