Aboveground soil C inputs in the ecotone between Scots pine and Pyrenean oak in Sierra de Guadarrama uri icon

abstract

  • Aboveground litterfall from Pyrenean oak (Quercus pyrenaica Willd. a semi-deciduous species), mixed Pyrenean oak-pine and pine (Pinus sylvestris L.) forest stands was surveyed in two sites in a Mediterranean mountain area during a period of 36 and 29 months, respectively. Separation in different litterfall fractions was performed, and C content of each fraction was measured to calculate the C flux to the soil due to litterfall. Our results showed that litterfall input was higher in pine stands than in Pyrenean oak stands (1.8-2.4 Mg C ha(-1) year(-1) at pine plots and 0.9-1.4 Mg C ha(-1) year(-1) at oak plots) and mixed plots showed intermediate values. Needles or leaves contributed about 50% to total litterfall, underpinning the importance of the rest of materials in the soil C input. The seasonal pattern showed a maximum in Pyrenean oak stands in autumn-early winter, while the pine stands had the maximum in summer, which is in consonance with the physiology of fall of broadleaves and coniferous trees in these latitudes, but clearly differs from needle-shed in Central and Northern Europe. A dry-spring year corresponded to a lower leaf fall during the following autumn, and leaf abscission came some weeks earlier than a year with a rainy spring.

publication date

  • 2011
  • 2011