The leaf economics spectrum^1,2 and the global spectrum of plant forms and functions³ revealed fundamental axes of variation in plant traits, which represent different ecological strategies that are shaped by the evolutionary development of plant species². Ecosystem functions depend on environmental conditions and the traits of species that comprise the ecological communities⁴. However, the axes of variation of ecosystem functions are largely unknown, which limits our understanding of how ecosystems respond as a whole to anthropogenic drivers, climate and environmental variability^4,5. Here we derive a set of ecosystem functions⁶ from a dataset of surface gas exchange measurements across major terrestrial biomes. We find that most of the variability within ecosystem functions (71.8%) is captured by three key axes. The first axis reflects maximum ecosystem productivity and is mostly explained by vegetation structure. The second axis reflects ecosystem water-use strategies and is jointly explained by variation in vegetation height and climate. The third axis, which represents ecosystem carbon-use efficiency, features a gradient related to aridity, and is explained primarily by variation in vegetation structure. We show that two state-of-the-art land surface models reproduce the first and most important axis of ecosystem functions. However, the models tend to simulate more strongly correlated functions than those observed, which limits their ability to accurately predict the full range of responses to environmental changes in carbon, water and energy cycling in terrestrial ecosystems^7,8.

叶子经济学谱^1,2和植物形态和功能的全球谱³揭示了植物性状变异的基本轴，它们代表了由植物物种进化发展形成的不同生态策略²。生态系统的功能取决于环境条件和构成生态群落的物种的特征⁴。然而，生态系统功能的变化轴在很大程度上是未知的，这限制了我们对生态系统如何作为一个整体响应人为驱动因素、气候和环境变化^4,5的理解。在这里，我们推导出一组生态系统功能⁶来自主要陆地生物群落的地表气体交换测量数据集。我们发现生态系统功能内的大部分可变性 (71.8%) 由三个关键轴捕获。第一个轴反映最大的生态系统生产力，主要由植被结构解释。第二个轴反映了生态系统用水策略，并由植被高度和气候的变化共同解释。第三个轴代表生态系统碳利用效率，具有与干旱相关的梯度，主要由植被结构的变化来解释。我们展示了两个最先进的陆地表面模型再现了生态系统功能的第一个也是最重要的轴。然而，这些模型倾向于模拟比观察到的更强烈的相关函数，^7,8。