Abstract Aridity has increased in recent decades in the Mediterranean Basin and is projected to continue to increase in the coming decades. We studied the consequences of drought on the concentrations, stoichiometries and stocks of carbon (C), nitrogen (N), phosphorus (P) and potassium (K) in leaves, foliar litter of a three dominant woody species and soil of a Mediterranean montane holm oak forest where soil-water content was experimentally reduced (15 % lower than the control plots) for 15 years. Nitrogen stocks were lower in the drought plots than in the control plots (8.81 ± 1.01 kg ha−1 in the forest canopy and 856 ± 120 kg ha−1 in the 0−15 cm soil layer), thus representing 7 and 18 % lower N stocks in the canopy and soil respectively. δ15N was consistently higher under drought conditions in all samples, indicating a general loss of N. Foliar C and K stocks were also lower but to a lesser extent than N. Decreases in biomass and C and N stocks due to drought were smallest for the most dominant tall shrub, Phillyrea latifolia, so our results suggest a lower capacity of this forest to store C and nutrients but also substantial resulting changes in forest structure with increasing drought.

中文翻译：

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长期干旱降低了地中海圣栎林中的生态系统 C 和养分储存

摘要 近几十年来，地中海盆地的干旱程度有所增加，预计未来几十年还将继续增加。我们研究了干旱对树叶、三种主要木本植物的凋落物和地中海山地土壤中碳 (C)、氮 (N)、磷 (P) 和钾 (K) 的浓度、化学计量和储量的影响15 年间通过实验降低土壤含水量（比对照地块低 15%）的圣栎林。干旱样地的氮储量低于对照样地（森林冠层为 8.81 ± 1.01 kg ha-1，0-15 cm 土层为 856 ± 120 kg ha-1），因此分别低 7% 和 18%分别在冠层和土壤中储存氮。在干旱条件下，所有样品的 δ15N 始终较高，表明 N 总体损失。