In the past several decades, field studies have shown that woody plants can access substantial volumes of water from the pores and fractures of bedrock^1,2,3. If, like soil moisture, bedrock water storage serves as an important source of plant-available water, then conceptual paradigms regarding water and carbon cycling may need to be revised to incorporate bedrock properties and processes^4,5,6. Here we present a lower-bound estimate of the contribution of bedrock water storage to transpiration across the continental United States using distributed, publicly available datasets. Temporal and spatial patterns of bedrock water use across the continental United States indicate that woody plants extensively access bedrock water for transpiration. Plants across diverse climates and biomes access bedrock water routinely and not just during extreme drought conditions. On an annual basis in California, the volumes of bedrock water transpiration exceed the volumes of water stored in human-made reservoirs, and woody vegetation that accesses bedrock water accounts for over 50% of the aboveground carbon stocks in the state. Our findings indicate that plants commonly access rock moisture, as opposed to groundwater, from bedrock and that, like soil moisture, rock moisture is a critical component of terrestrial water and carbon cycling.

在过去的几十年里，实地研究表明，木本植物可以从基岩的孔隙和裂缝中获取大量的水^1,2,3。如果像土壤水分一样，基岩储水是植物可用水的重要来源，那么可能需要修改有关水和碳循环的概念范式，以纳入基岩特性和过程^4,5,6. 在这里，我们使用分布式、公开可用的数据集对美国大陆的基岩储水量对蒸腾作用的贡献进行了下限估计。美国大陆基岩水利用的时空格局表明，木本植物广泛获取基岩水进行蒸腾。跨越不同气候和生物群落的植物定期获取基岩水，而不仅仅是在极端干旱条件下。在加利福尼亚州，每年的基岩水蒸腾量超过了人造水库中储存的水量，获取基岩水的木本植被占该州地上碳储量的 50% 以上。我们的研究结果表明，植物通常从基岩中获取岩石水分，而不是地下水，并且，