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Báo cáo lâm nghiệp: "Dynamics of natural regeneration of even-aged beech (Fagus sylvatica L.) stands at different shelterwood densities"

Tham khảo luận văn - đề án 'báo cáo lâm nghiệp: "dynamics of natural regeneration of even-aged beech (fagus sylvatica l.) stands at different shelterwood densities"', luận văn - báo cáo phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | JOURNAL OF FOREST SCIENCE 56 2010 12 580-588 Dynamics of natural regeneration of even-aged beech Fagus sylvatica L. stands at different shelterwood densities J. F. B. Pena J. Remes L. Bílek Faculty of Forestry and Wood Sciences Czech University of Life Sciences Prague Prague Czech Republic ABSTRACT The article presents results of research focused on the development of natural regeneration of beech stands in the National Natural Reserve Vodèradské buciny based on information acquired in regeneration plots established in 2004 and 2009. After five years of the study 5 different generations of beech representing 97.4 of the whole woody regeneration were registered. In the second year of life the two oldest generations of seedlings had the highest mortality registered so far. The last year survival of seedlings was not influenced by increased canopy openings as a result of harvest or mortality. The data from a new plot with higher stand density confirmed the negative effect of high parent stand density on the formation of new regeneration. An elevated proportion of litter in the ground cover was found to be negatively related to the establishment and survival of beech seedlings. Keywords European beech Fagus sylvatica L. natural regeneration natural reserve stand density Beech forests of the Czech Republic are mostly located in protected areas beech can be considered as the most important commercial broadleaved tree species playing an important role in the conversion of extensive spruce monocultures Jurasek 2000 . The species is traditionally reproduced by natural regeneration based on the frequency of mast years which occur every 4 to 6 years on average and such a frequency is said to be encouraged by a temperature higher than 30 C from July to September of the prior year although site index and high deposition of atmospheric nitrogen can also affect this frequency positively Overgaard et al. 2007 . Flowering and seed production of European beech begin at about 40-50 .