Natural regeneration analysis of Pinus pinaster Ait. in the sandy areas of Almazan-Bayubas (Soria, Spain)

Natural regeneration is a key factor for the maintenance of forest stands through the time. Research on this process, considering the different forestry treatments to manage them, it is high important for the development Of Sustainable forestry models. In this study, numerous ecological variables, related to stand, site and seedlings, have been analysed in areas that have been undergone clearcutting leaving seed trees, in Almazan-Bayubas (Soria, Spain). The sampling was systematic using a 100 m squared grid and pots were divided into four quadrants of 4.9 m(2) of surface and 2.5 m of radius. After data descriptive analysis, several models were built to predict the regeneration probability, viable density, productivity and rate of height's growth. Explanatory variables including in were directly related to soil cover, being shrub cover, logging cover and soil sand content the more significant.