Abstract• The resorption of nutrients (mainly N and P) from senescing leaves may be a key component of adaptive mechanisms that conserve scarce nutrients. Resorption may be expressed in two ways as resorption efficiency (RE) which is the ratio of the resorbed amounts of nutrient losses during leaf senescence in relation to its prior amount deposited in leaves and resorption proficiency (RP) is the level to which nutrient concentration per unit leaf mass is reduced in senescent leaves.• There is still much debate whether or not different life-forms (i.e. deciduous and evergreen species) show different foliar resorption patterns. Two sympatric species, namely Quercus petraea (Mattuschka) Liebl. subsp. iberica (Steven ex Bieb.) Krassiln. (deciduous) and Arbutus andrachne L. (evergreen) along an elevational gradient were compared with each other to determine whether or not nitrogen and phosphorus resorption efficiency and proficiency varies along the elevational gradient and which leaf parameters were as related to RE and RP.• NRE was found to be rather low in Q. petraea subsp. iberica compared to other deciduous species. Similarly, PRE in A. andrachne was rather low compared to other evergreen species. Mean residence time (MRT) measures how long a unit of nitrogen (MRT N ) and phosphorus (MRT P ) is present in the plant. MRT N and MRT P were found to be considerably higher in A. andrachne compared to Q. petraea subsp. iberica. In both species, the foliar N/P ratio was below 14 along the elevational gradient and, according to this threshold value, N-limitation occurred in the study area. Although both species in the present study show incomplete resorption deciduous species was more proficient as compared to evergreen one due to low N and P concentrations in senescent leaves. Based on the significant correlations (p < 0.05 and 0.01) between MRT and foliar resorption, it can be concluded that MRT could interfere with the mechanisms controlling nutrient resorption.Mots-clés : stratégies de Grime / temps moyenne de résidence (MRT) / rapport N/P / efficience de la résorption / capacité de résorption / espèces sympatriques Résumé -Résorption foliaire chez Quercus petraea subsp. iberica et Arbutus andrachne le long d'un gradient altitudinal.• La résorption des éléments nutritifs (essentiellement N et P) par sénescence des feuilles peut être une composante clé des mécanismes d'adaptation qui permettent de conserver les rares éléments nutritifs. La résorption peut être exprimée de deux façons : l'efficience de résorption (RE) qui est le rapport entre la quantité résorbée des pertes d'éléments nutritifs au cours de la sénescence des feuilles par rapport à son montant déposé auparavant dans les feuilles et la capacité de résorption (RP) qui est le niveau auquel la concentration des éléments nutritifs par unité de masse de feuilles est réduite dans les feuilles sénescentes.• Il reste encore beaucoup de débat pour déterminer si les différentes formes de vie (c'est-à-dire les espèces décidues et les espèces sempervirentes) prése...

-Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball occurs in the Mediterranean region, on the southern part of Turkey and has been widely used in landscape planning and stabilization of coastal dunes. In this study foliar N and P resorption and foliar N, P and K concentrations (on a leaf mass basis) were investigated in J. oxycedrus subsp. macrocarpa. Foliar N, P, and K concentrations and absolute and proportional N and P resorption rates along the topographic position were not changed significantly. Significant correlations were found between absolute and proportional P resorption rates and soil moisture status. However, there were no significant correlation between absolute and proportional N resorption rates and soil moisture status. Foliar N and proportional N resorption were significantly correlated although absolute N resorption was not significantly correlated with foliar N. However, foliar P was significantly correlated both absolute and proportional P resorption. Juniperus oxycedrus

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