Regeneration after wildfire in communities dominated by Pinus pinaster, an obligate seeder, and in others dominated by Quercus pyrenaica, a typical resprouter

Abstract

The effects of wildfire on vegetation regeneration in communities dominated by Quercus pyrenaica and those dominated by Pinus pinaster in NW Spain were compared. In order to study changes in the composition and structure of both types of community, permanent plots were established in areas dominated by Q. pyrenaica and those dominated by P. pinaster. All were burned by wildfires at the end of summer. In each plot a permanent transect of 20 m  1 m was established. Basal cover of the plant species present was analysed. In both types of community the global cover values generally increased throughout the study period. In the oak communities the species that appear in the first years are those that will dominate in the mature stage, like Q. pyrenaica and Erica australis. Both species are typical resprouters: from shoots on the rhizome or the stem of subterranean roots in the case of Q. pyrenaica and from lignotubers in the case of E. australis. Among the other species, herbaceous perennials dominated during the first year after the fire, Luzula lactea being the most representative. The percentage of bare soil decreased very rapidly after the first year of regeneration. However, in the P. pinaster communities the species that appeared with higher cover values during the first and second year after fire were seeders, like P. pinaster and Halimium alyssoides. Other species that appeared in these communities were Chamaespartium tridentatum, and E. australis. Amongst the herbaceous perennials, the most representative species was the Liliacea Ornithogalum umbellatum, which appeared throughout the study period in all the burned plots. The percentages of bare soil were higher than in the oak communities. Structural parameters such as diversity and specific richness were much higher in the community dominated by oak than in the pine stand. In general, regeneration after wildfire in the Pinus community was slower than in oak communities.

Burn severity influence on post-fire vegetation cover resilience from Landsat MESMA fraction images time series in Mediterranean forest ecosystems

“…7) agreed with the results of previous non-remote sensing-based studies also centered on P. pinaster. In our study area, Calvo et al (2003Calvo et al ( , 2008Calvo et al ( , 2013 concluded that the dominant species, P. pinaster, had a predominantly high rate of natural regeneration. Mean seedling height showed a significant increase in time (5 years) at the study area from 1.7 to 49.5 cm.…”

Modelling post-fire vegetation recovery in Portugal

“…The observed increase in wildfires has a drastic impact on biological productivity and composition of Mediterranean ecosystems (Calvo et al, 2003(Calvo et al, , 2005. However the effects of fire on ecosystems are very complex since they depend on fire regimes and characteristics (Naveh, 1995) as well as on the response of vegetation to such regimes and on environmental factors (De Luís et al 2001.…”

Post-fire natural regeneration of a Pinus pinaster forest in NW Spain

“…Fire creates open areas, which favour the germination of species by removing established vegetation, and also has direct effects on germination and seedling survival (Hanley and Fenner 1998). The passage of fire may facilitate germination and the development of several species by changing the mineral nutrient content of the environment (Marcos 1997;Calvo et al 2003Calvo et al , 2005. Trends in secondary succession beginning after a fire depend on several factors, including species composition in the initial community, fire severity, the season in which burning occurs (Dominguez et al 2002) and the existence of either a soil or aerial seed bank able to survive disturbances (Ferrandis et al 1996).…”

“…In addition, competitive effects on the establishment of P. pinaster seedlings can also be expected in forests where the dominant understorey species consist mostly of woody and herbaceous resprouters (Calvo et al 2003). Several studies have highlighted rapid post-fire regeneration in resprouter species such as Erica australis (Willk.…”