Montserrat Ribas

Publications (2)4.17 Total impact

• Source

  Available from: Filipe Campelo

  Article: Climate controls act at different scales on the seasonal pattern of Quercus ilex L. stem radial increments in NE Spain

  Emilia Gutiérrez, Filipe Campelo, J. Julio Camarero, Montserrat Ribas, Elena Muntán, Cristina Nabais, Helena Freitas
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  ABSTRACT: Long-term data on radial increment dynamics in Mediterranean species may identify which climatic variables are the main constraints for radial growth and at which temporal scales they act. To this end, we examined stem radial fluctuations in Quercus ilex L., the dominant evergreen oak species in the Western Mediterranean Basin, over a period of 11years (1994–2004) at a coastal site in north-eastern Spain. We used manual band dendrometers to record girth changes in trees on north- and south-facing slopes. Annual increments measured by dendrometers showed good agreement with annual tree-ring width. North-facing trees showed a lower long-term cumulative radial increment than south-facing trees. The seasonal radial increment pattern of Q. ilex was bimodal, being characterized by a greater increase in May and a lesser, more variable increase peak in September. Both phases corresponded to warm and moist climatic conditions, whereas radial increase of stems stopped in winter and occasionally in summer. Considering the whole year, mean maximum air temperature was the main factor positively affecting radial increment of Q. ilex from short- (5days) to- long (30days) time scales, whereas the accumulated precipitation exerted a similar effect at longer (30days) scales, but only on south-facing trees. In summer, all trees were positively correlated with precipitation at long-time scales (30days); however, only stem increment of south-facing trees showed a significant relation to the temperature at short-time scales (10days). We confirmed the dominant role of temperature as the major constraint on radial increment at short time scales, despite most previous studies were mostly biased towards precipitation effects at monthly scales. KeywordsBand dendrometer–Drought–Mediterranean climate–Bimodal growth–Holm oak
  Trees 04/2012; 25(4):637-646. · 1.68 Impact Factor
• Source

  Available from: Emilia Gutiérrez

  Article: Forest structure and fire history in an old Pinus nigra forest, eastern Spain

  Peter Z Fulé, Montserrat Ribas, Emilia Gutiérrez, Ramón Vallejo and Margot W Kaye
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  ABSTRACT: Wildfires have decimated forests of Pinus nigra in the Mediterranean Basin in recent decades, but little is known about the fire ecology of this native species. We sampled three small relict forest sites on Sierra Turmell, Castellón, Valencia, northeastern Spain, to determine forest structure and past fire events. The forest was characterized by relatively large and old trees (mean 158 year, max 362 year). Fire history was affected by obliteration of some fire scars, but we determined 11 fire dates in the past 172 years. The minimum fire-free interval was 2 years, maximum 57 years. Fire dates were not linked with dry climatic conditions, possibly due to occupational burning by pastoralists. Compared to inventory data averages for P. nigra in northeastern Spain (Catalunya), the old forest at Sierra Turmell supported over twice the basal area and over 2.5 times the biomass, with a comparable advantage in terms of carbon storage. Carbon sequestration, on the other hand, was over six times higher in the younger forests. The relict forest at Sierra Turmell provides evidence of multi-aged forest structure persisting through numerous surface fires over several centuries. This example may be useful for guiding management of younger forests and for ecological restoration of degraded areas.
  Forest Ecology and Management 01/2008; 255(3-4):1234–1242. · 2.49 Impact Factor