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Background:The lack of regeneration of cork oak (Quercus suber) is putting at risk the conservation of themontado. Biotic and abiotic factors as well as management are thought to constrain regeneration. Aims:Identify limitations to regeneration during the early stages and relate them to management practices. Methods:Experimental burying of acorns was carried out at three distinctly managedmontados. Cache predation, seedling emergence, survival and resprouting were monitored during the first year. Regeneration was evaluated by testing the effect of biotic and abiotic factors in each stage. Results:Regeneration was determined by temperature and relative humidity. Early emerged seedlings showed higher drought tolerance and resprouting ability. Bigger acorns and higher plant cover significantly assisted emergence, survival and resprouting. Mortality causes were drought (38%) and mechanical ploughing (33%), while cache predation and browsing on seedlings were low (1.7%, when excluding tag effect on cache predation, and 0.6%, respectively). Seedling emergence and survival of drought were significantly lower in the most disturbed site than in the other two sites. Conclusions:Abiotic factors restrain regeneration while acorn size and plant cover are key factors determining seedling emergence and survival. The lack of regeneration may be overcome in the short term by preserving the shrub layer. Moreover, reforestation by direct sowing should be also considered. [ABSTRACT FROM PUBLISHER]

The article presents a study which investigates the variables that affect the spore phenology of two evergreen ferns Woodwardia radicans and Culcita macrocarpa in Sâo Miguel, Azores. The study used binomial distribution and Generalized Linear Models (GLMs) to determine the spore release date and maturation. The result indicates that the biotic pressures such as presence of spore feeders result in the long-term causes of the spore maturation and release of W. radicans and C. macrocarpa.