Clone identification of 38 Japanese beech plus-tree clones and possibility of paternity analysis for their open-pollinated progenies were examined using 11 isozyme loci encoding eight enzyme systems to enhance the accuracy of clone archive management and the utilization of seeds produced in masting years. Twenty-four alleles were detected at the 11 loci. The proportion of polymorphic loci, the average number of alleles per locus, the effective number of alleles per locus, and the expected and observed values of average heterozygosity were 54.5%, 2.18, 1.28, 0.159 and 0.158, respectively. Japanese beech clones retained the genetic variability as large as woody plants did. The 38 clones were divided into 28 multilocus genotypes. As 23 clones had unique multi-locus genotypes, clone identification was possible for those clones. Ajigasawa 104 clone had three rare alleles. Therefore, complete paternity identification will be possible for the progenies whose pollen donor was the Ajigasawa 104. Similarly, partial paternity identification was possible in the case of other nine plus-tree clones contributing as pollen donor.

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We examined the extent and the characteristics of the northern coastal forests along the sea of Japan. Firstly, many terms about the forms of the coast were examined and rearranged. Secondly, weather division, coast types distribution, bio-diversity division, coastal disaster distribution and geotectonic division were examined for setting the bounds of the "North-Eastern coast along the sea of Japan", which were applied from the coast of Shibata City to the Tsugaru coast. Thirdly, the coastal forests were defined as "forest community growing not only on the dune area but on the cliffs under a salty wind condition, and the structure and component of the forests are different from those of the inland forests in case of a natural stand". Based upon these findings, the potential vegetation and actual vegetation of "North-Eastern coast along the sea of Japan" were compared to those of the "Pacific coast". The characteristics of coastal forests of "the North-Eastern coast along the sea of Japan" were clarified as follows: Pinus thunbergii were planted in large area on the dunes for the wind break, and the potential vegetation left on the rocky coasts were partially distributed from the nearby volcanic mountains.

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We studied the initial regenerative process of Persea thunbergii in a mature P. thunbergii forest and the surrounding deciduous forest at its northern limit, Yamagata Prefecture, northeastern Japan. A few seeds germinated in the autumn of the year dispersed, but most seeds germinated the next summer under the closed crowns in the P. thunbergii forest. In contrast, at the boundary between the P. thunbergii forest and the deciduous forest, 40% of the seeds germinated in the autumn. The most frequent mortality factor was predation of seeds by rodents; damping-off by fungi for seedlings. Damping-off occurred more frequently in the P. thunbergii forest than in the deciduous forest and the boundary. Twoyear-old seedlings in the P. thunbergii forest were significantly smaller than those in the boundary and the deciduous forest, probably because there was less total light energy in the P. thunbergii forest. Thus the boundary and the deciduous forest have more safe sites for P. thunbergii seedlings than the P. thunbergii forest. The seedlings that germinated in autumn 1996 grew significantly faster than those germinated in summer 1997 in the boundary. This result suggests that the establishment and growth of seedlings were affected by their germination season in the boundary.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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