Variation in seed production among years and among individuals in 11 broadleaf tree species in northern Japan

Autor: Ichiro Watanabe, Mika Takiya, Norio Mizui, Michiyasu Yasaka, Yasuyuki Oono
Rok vydání: 2008
Předmět:
Zdroj: Journal of Forest Research. 13:83-88
ISSN: 1610-7403
1341-6979
DOI: 10.1007/s10310-007-0052-6
Popis: Seed production is the most problematic part of tree regeneration and is the least amenable to control by silvicultural management. Understanding variability in seed production among years and among trees will allow better planning of seed collection for seedling production and natural regeneration. We estimated the extent of variability in seed production among years and within years among individual trees. Specifically, we measured individual annual seed production in 11 woody species in Hokkaido, northern Japan. We analyzed the coefficient of variation (CV) of seed production among years and among individual trees. We used population- and individual-based CVs (CVpt and $$ \overline{{{\text{CV}}}} _{{{\text{it}}}} $$ ) to estimate the variability in seed production among individual trees. Alnus hirsuta, in which these CVs among trees were maximal, will require further analyses of the spatial patterns of seed production among individual trees. Additionally, we used population- and individual-based CVs (CVpy and $$ \overline{{{\text{CV}}}} _{{{\text{iy}}}} $$ ) to estimate the variability in seed production among years. The $$ \overline{{{\text{CV}}}} _{{{\text{iy}}}} $$ was statistically higher than $$ \overline{{{\text{CV}}}} _{{{\text{it}}}} $$ in 2 of the 11 species: Betula maximowicziana and Sorbus alnifolia. Activities for the regeneration of these species should regard the annual variation in seed production as more important than individual variation. For the nine species in which $$ \overline{{{\text{CV}}}} _{{{\text{it}}}} $$ was similar to $$ \overline{{{\text{CV}}}} _{{{\text{iy}}}} , $$ even if seed production by specific trees was not sufficient for regeneration in a particular year, other trees or stands often had high seed production in that year. We discuss the relative importance of annual and individual variability in determining efficient methods for artificial and natural regeneration of these woody plant species.
Databáze: OpenAIRE
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