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24, chemin de Borde Rouge -Auzeville - CS52627 31326 Castanet Tolosan cedex - France

Last update: May 2021

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Gradient altitudinal Pyrénéen

Nom du dispositif
Gradient altitudinal Pyrénéen
Vallée d’Ossau (Pyrénées atlantiques) et Vallée de Luz Saint Sauveur (Pyrénées centrales)


Type de dispositif
Gradient altitudinal
Mono ou multi-site
Insertion dans un réseau
Site Web
L’aire d’étude est localisée dans deux vallées du sud ouest de la France. L’étude s’est déroulée le long d’un gradient altitudinal dans le but d’obtenir des situations climatiques très contrastées pour le suivi phénologique des populations. Dans cette étude, le terme population est employé pour désigner l’échantillon d’individus d’une espèce à une altitude donnée. Les populations d’arbres étudiées ont ainsi été échantillonnées le long de gradients altitudinaux, de 100 m à 1600 m, dans la vallée d’Ossau (Pyrénées atlantiques) et la vallée de Luz Saint Sauveur (Pyrénées centrales). La proximité géographique de ces deux vallées leur fait bénéficier d’un climat montagnard océanique comparable. La pluviométrie annuelle à Tarbes calculée sur la période allant de 1946 à 2001 est de 1079 mm et la température moyenne annuelle sur cette même période est de 12.0°C.  Les stations ont été choisies à cinq niveaux altitudinaux de 100 m, 400 m, 800 m, 1200 m et 1600 m, plus ou moins 50 m, dans les étages collinéens et montag...
Date(s) d'installation
Type de substrat
Espèces structurantes
Quercus petraea, Fagus sylvatica
Variables testées/observées
instrumentation-équipement particulier
Station météo
Nature des données / type de mesures
Date de débourrement, DBH, hauteur, nombre et masse des glands
Disponibilité des données
Données publiées uniquement
Gestionnaire des données
Sylvain Delzon
Contact scientifique
Sylvain Delzon
Partenaires (installation/gestion/suivi)
  • Denéchère, R., Delpierre, N., Apostol, E. N., Berveiller, D., Bonne, F., Cole, E., Delzon S.  … & Lebourgeois, F. (2019). The within-population variability of leaf spring and autumn phenology is influenced by temperature in temperate deciduous trees. International journal of biometeorology, 1-11.
  • Gauzere, J., Delzon, S., Davi, H., Bonhomme, M., de Cortazar-Atauri, I. G., & Chuine, I. (2017). Integrating interactive effects of chilling and photoperiod in phenological process-based models. A case study with two European tree species: Fagus sylvatica and Quercus petraea. Agricultural and Forest Meteorology, 244, 9-20.
  • Caignard T, Kremer A, Firmat C, Nicolas M, Venner S, Delzon S. (2017) Increasing spring temperatures favor oak seed production in temperate areas. Scientific Reports 7: 8555.
  • Venner S., A. Siberchicot, P-F. Pélisson, M-C. Bel-Venner, M. Nicolas, F. Débias, V. Miele, S. Sauzet, V. Boulanger and S. Delzon (2016) Trading-off seed number versus seed size may promote masting within plant population. American Naturalist 188: 66-75.
  • Dantec C.F., H. Ducasse, X. Capdevielle, O. Fabreguettes, S. Delzon, M-L. Desprez-Loustau (2015) Avoidance of spring frost and disease through phenological variations in oak populations along elevation gradients. Journal of Ecology 103: 1044-1056
  • Dantec C.F., Y. Vitasse, M. Bonhomme, J-M. Louvet, A. Kremer and S. Delzon (2014) Chilling and heat requirements for leaf unfolding in European beech and sessile oak populations at the southern limit of their distribution range. International Journal of Biometeorology 58: 1853-1864.
  • Kremer A., Potts B. M. and S. Delzon (2014) Genetic divergence in forest trees: understanding the consequences of climate change. Functional Ecology 28: 22-36.
  • Vitasse Y., Delpierre N., François C., Dufrêne E., Kremer A., Chuine I. and S. Delzon (2011) Assessing the effects of climate change on the phenology of European temperate trees. Agricultural and Forest Meteorology 151: 969-980.
  • Bresson C. C., Y. Vitasse, A. Kremer and S. Delzon (2011) To what extent is altitudinal variation of functional traits driven by genetic adaptation in European oak and beech? Tree Physiology 31: 1164-1174.
  • Guyon D., Guillot M., Vitasse Y., Cardot H., Hagolle O., Delzon S. and J-P Wigneron (2011) Monitoring elevation variations in leaf phenology of deciduous broadleaf forests from SPOT/VEGETATION time-series. Remote Sensing of Environment 115: 615-627.
  • Desprez-Loustau M.L., Y. Vitasse, S. Delzon, X. Capdevielle, B. Marçais and A. Kremer (2010) Are plant pathogen populations adapted for encounter with their host? A case study of phenological synchrony between oak and an obligate fungal parasite along an altitudinal gradient Journal of Evolutionary Biology 23: 87-97.
  • Bresson, C. C., A. S. Kowalski, A. Kremer and S. Delzon (2009) Evidence of altitudinal increase in photosynthetic capacity: gas exchange measurements at ambient and constant CO2 partial pressures. Annals of Forest Science 66: 55.
  • Vitasse Y., A. Porté, A. Kremer, R. Michalet and S. Delzon (2009) Responses of canopy duration to temperature changes in four temperate tree species: relative contributions of spring and autumn leaf phenology. Oecologia 161: 187-198.
  • Vitasse Y., Delzon S., Dufrêne E., Pontailler J-Y., J-M Louvet, A. Kremer and R. Michalet (2009) Leaf phenology sensitivity to temperature in European trees: do within-species populations exhibit similar responses? Agricultural and Forest Meteorology 149: 735-744.

Kremer A., Potts B. M. and S. Delzon (2014) Genetic divergence in forest trees: understanding the consequences of climate change. Functional Ecology 28: 22-36.