Leaf size of woody dicots predicts ecosystem primary productivity

A key challenge in ecology is to understand the relationships between
organismal traits and ecosystem processes. Here, with a novel dataset of
leaf length and width for 10,480 woody dicots in China and 2,374 in North
America, we show that the variation in community mean leaf size is highly
correlated with the variation in climate and ecosystem primary
productivity, independent of plant life form. These relationships likely
reflect how natural selection modifies leaf size across varying climates
in conjunction with how climate influences canopy total leaf area. We find
that the leaf size‒primary productivity functions based on the Chinese
dataset can predict productivity in North America and vice-versa. In
addition to advancing understanding of the relationship between a
climate-driven trait and ecosystem functioning, our findings suggest that
leaf size can also be a promising tool in paleoecology for scaling from
fossil leaves to paleo-primary productivity of woody ecosystems.

生态学领域的核心挑战之一，在于阐明生物性状与生态系统过程之间的内在联系。本研究使用一套涵盖中国境内10480种木本双子叶植物（woody dicots）以及北美地区2374种木本双子叶植物叶片长度与宽度数据的全新数据集，证实群落平均叶尺寸的变异与气候及生态系统初级生产力的变异呈高度相关，且该关联不受植物生活型的影响。这类关联或可反映自然选择如何在不同气候条件下塑造叶尺寸，同时结合气候对冠层总叶面积的调控作用。我们发现，基于中国数据集构建的叶尺寸-初级生产力函数，可用于预测北美地区的生态系统生产力，反之亦然。本研究不仅推进了我们对气候驱动性状与生态系统功能之间关联的认知，其研究结果还表明，叶尺寸可作为古生态学（paleoecology）领域一项颇具前景的工具，用于从化石叶片推演木本生态系统的古初级生产力。