Background and Aims Leaf size has considerable ecological relevance, making it desirable to obtain leaf size estimations for as many species worldwide as possible. Current global databases, such as TRY, contain leaf size data for ~30 000 species, which is only ~8% of known species worldwide. Yet, taxonomic descriptions exist for the large majority of the remainder. Here we propose a simple method to exploit information on leaf length, width and shape from species descriptions to robustly estimate leaf areas, thus closing this considerable knowledge gap for this important plant functional trait. Methods Using a global dataset of all major leaf shapes measured on 3125 leaves from 780 taxa, we quantified scaling functions that estimate leaf size as a product of leaf length, width and a leaf shape-specific correction factor. We validated our method by comparing leaf size estimates with those obtained from image recognition software and compared our approach with the widely used correction factor of 2/3. Key Results Correction factors ranged from 0.39 for highly dissected, lobed leaves to 0.79 for oblate leaves. Leaf size estimation using leaf shape-specific correction factors was more accurate and precise than estimates obtained from the correction factor of 2/3. Conclusion Our method presents a tractable solution to accurately estimate leaf size when only information on leaf length, width and shape is available or when labour and time constraints prevent usage of image recognition software. We see promise in applying our method to data from species descriptions (including from fossils), databases, field work and on herbarium vouchers, especially when non-destructive in situ measurements are needed.

中文翻译：

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根据叶子长度、宽度和形状估计叶子大小


背景和目标 叶子大小具有相当大的生态相关性，因此需要获得全世界尽可能多的物种的叶子大小估计值。当前的全球数据库（例如 TRY）包含约 30 000 个物种的叶子大小数据，这仅占全球已知物种的约 8%。然而，其余大部分都存在分类学描述。在这里，我们提出了一种简单的方法，利用物种描述中的叶长、宽度和形状信息来稳健地估计叶面积，从而缩小这一重要植物功能性状的巨大知识差距。方法 使用对 780 个分类单元的 3125 个叶子测量的所有主要叶子形状的全局数据集，我们量化了缩放函数，该函数将叶子大小估计为叶子长度、宽度和叶子形状特定校正因子的乘积。我们通过将叶子尺寸估计值与图像识别软件获得的估计值进行比较来验证我们的方法，并将我们的方法与广泛使用的校正因子 2/3 进行比较。主要结果 校正因子的范围从高度解剖、浅裂叶的 0.39 到扁圆形叶的 0.79。使用特定于叶子形状的校正因子来估计叶子大小比通过 2/3 校正因子获得的估计值更准确和精确。结论 我们的方法提供了一种易于处理的解决方案，当仅提供叶片长度、宽度和形状信息时，或者当劳动力和时间限制无法使用图像识别软件时，可以准确估计叶片尺寸。我们看到将我们的方法应用于物种描述（包括化石）、数据库、实地工作和植物标本馆凭证中的数据的希望，特别是在需要无损原位测量时。