Abstract Gypsum-exclusive species (gypsophiles), are restricted to gypseous soils in natural environments. However, it is unclear why gypsophiles display greater affinity to gyspeous soils than other soils. These plants are edaphic endemics, growing in alkaline soils with high Ca and S. Gypsophiles tend to show higher foliar Ca and S, lower K and, sometimes, higher Mg than non-exclusive gypsum species, named gypsovags. Our aim was to test if the unique leaf elemental signature of gypsophiles could be the result of special nutritional requirements linked to their specificity to gypseous soils. These nutritional requirements could hamper the completion of their life cycle and growth in other soil types. To test this hypothesis, we cultivated five gypsophiles and five gypsovags dominant in Spanish gypsum outcrops on gypseous and calcareous (non-gypseous) field soil for 29 months. We regularly measured growth and phenology, and differences in leaf traits, final biomass, individual seed mass, seed viability, photosynthetic assimilation and leaf elemental composition. We found all the gypsophiles studied were able to complete their life cycle in non-gypseous soil, producing viable seeds, attaining greater biomass and displaying higher photosynthetic assimilation rates than in gypseous soil. The leaf elemental composition of some species (both gypsophiles and gypsovags) shifted depending on soil, although none of them showed leaf deficiency symptoms. Regardless of soil type, gypsophiles had higher leaf S, Mg, Fe, Al, Na, Mn, Cr and lower K than gypsovags. Consequently, gypsophiles have a unique leaf chemical signature compared to gypsovags of the same family, particularly due to their high leaf S regardless of soil conditions. However, these nutrient requirements are not sufficient to explain why gypsophiles are restricted to gypsum soil in natural conditions.

中文翻译：

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石膏专有植物在石膏内和石膏外比非专有物种积累更多的叶 S

摘要 石膏专有物种（gypsophiles），仅限于自然环境中的石膏土壤。然而，目前尚不清楚为什么满天星对膏状土壤的亲和力高于其他土壤。这些植物是土壤特有的植物，生长在具有高 Ca 和 S 的碱性土壤中。 满天星往往表现出较高的叶面 Ca 和 S、较低的 K，有时比非专有的石膏物种（称为 gypsovags）表现出更高的 Mg。我们的目的是测试满天星独特的叶子元素特征是否可能是与它们对石膏土壤的特异性相关的特殊营养需求的结果。这些营养需求可能会阻碍它们在其他土壤类型中完成生命周期和生长。为了检验这个假设，我们在 29 个月的石膏质和钙质（非石膏质）田间土壤上种植了在西班牙石膏露头中占主导地位的 5 种满天星菌和 5 种 gypsovags。我们定期测量生长和物候，以及叶片性状、最终生物量、个体种子质量、种子活力、光合同化和叶片元素组成的差异。我们发现所有研究的满天星都能够在非石膏质土壤中完成它们的生命周期，产生有活力的种子，获得更大的生物量，并显示出比在石膏质土壤中更高的光合同化率。一些物种（满天星和满天星）的叶子元素组成因土壤而异，尽管它们都没有表现出缺叶症状。无论土壤类型如何，满天星都比满天星具有更高的叶片 S、Mg、Fe、Al、Na、Mn、Cr ​​和更低的 K。最后，与同一家族的 gypsovags 相比，满天星具有独特的叶子化学特征，特别是由于它们的叶子 S 高而与土壤条件无关。然而，这些营养需求不足以解释为什么在自然条件下满天星只能在石膏土壤中生存。