Complex spatiotemporal phenological shifts as a response to rainfall changes

Authors

  • Josep Peñuelas,

    Corresponding author
    1. Unitat Ecofisiologia CSIC-CEAB-CREAF, CREAF (Center for Ecological Research and Forestry Applications), Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain;
      Author for correspondence:Josep Peñuelas Tel: +34 935812199 Fax: +34 935814151 Email: Josep.Penuelas@uab.es
    Search for more papers by this author
  • Iolanda Filella,

    1. Unitat Ecofisiologia CSIC-CEAB-CREAF, CREAF (Center for Ecological Research and Forestry Applications), Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain;
    Search for more papers by this author
  • Xiaoyang Zhang,

    1. Dept. of Geography/Center for Remote Sensing, Boston University, 725 Commonwealth Avenue, Boston, MA 02215, USA;
    Search for more papers by this author
  • Laura Llorens,

    1. Unitat Ecofisiologia CSIC-CEAB-CREAF, CREAF (Center for Ecological Research and Forestry Applications), Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain;
    Search for more papers by this author
  • Romà Ogaya,

    1. Unitat Ecofisiologia CSIC-CEAB-CREAF, CREAF (Center for Ecological Research and Forestry Applications), Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain;
    Search for more papers by this author
  • Francisco Lloret,

    1. Unitat Ecofisiologia CSIC-CEAB-CREAF, CREAF (Center for Ecological Research and Forestry Applications), Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain;
    Search for more papers by this author
  • Pere Comas,

    1. Cardedeu Field Station, C/Sant Miquel, 7, 08440 Cardedeu, Barcelona, Spain
    Search for more papers by this author
  • Marc Estiarte,

    1. Unitat Ecofisiologia CSIC-CEAB-CREAF, CREAF (Center for Ecological Research and Forestry Applications), Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain;
    Search for more papers by this author
  • Jaume Terradas

    1. Unitat Ecofisiologia CSIC-CEAB-CREAF, CREAF (Center for Ecological Research and Forestry Applications), Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona), Spain;
    Search for more papers by this author

Author for correspondence:Josep Peñuelas Tel: +34 935812199 Fax: +34 935814151 Email: Josep.Penuelas@uab.es

Summary

  • • Climatic warming produces significant gradual alterations in the timing of life-cycle events, and here we study the phenological effects of rainfall-pattern changes.
  • • We conducted ecosystem field experiments that partially excluded rain and runoff during the growing season in a Mediterranean forest and in a mediterranean shrubland. Studies of time-series of leaf-unfolding, flowering and fruiting over the last 50 yr in central Catalonia were carried out, and greenup onset in the Iberian Peninsula was monitored by satellite images.
  • • Experimental, historical and geographical changes in rainfall produced significant, complex and strongly species-specific, as well as spatially and temporally variable, phenological effects. Among these changes, it was found that in the Iberian Peninsula, greenup onset changes from spring (triggered by rising temperatures) in the northern cool-wet regions to autumn (triggered by the arrival of autumn rainfalls) in the southern warm-dry regions. Even in the mesic Mediterranean central Catalonia (NE of the peninsula) rainfall had a stronger relative influence than temperature on fruiting phenology.
  • • The results show that changes in rainfall and water availability, an important driver of climate change, can cause complex phenological changes with likely far-reaching consequences for ecosystem and biosphere functioning and structure. The seasonal shift in the Iberian Peninsula further highlights this importance and indicates that vegetation may respond to climate change not only with gradual, but also with abrupt temporal and spatial, changes in the timing of greenup onset.

Ancillary