Genetic Structure of a Picea polita Population in a Pinus densiflora Forest

ハリモミ天然林およびそれに隣接するアカマツ林において植生調査を行い,ハリモミの更新状況を調査した。その結果,約100年前に山火事で焼失し再生したアカマツを主林木とする林では,ハリモミが更新しているものの,純林状態で維持されてきた森林は衰退が著しく,ハリモミも更新していないことが明らかになった。また,アカマツ林におけるハリモミの遺伝子構造をアイソザイム分析によって明らかにした。ハリモミは樹高および樹齢により階層構造をなしているが,それぞれの階層での集団の遺伝的な変異は大きくなく,全体としてひとつの遺伝子プールを共有する集団と考えられた。The vegetation was surveyed in a natural forest of Picea polita and in its neighboring secondary forest of Pinus densiflora at Yamanakako, Yamanashi, Japan. Regeneration of P. polita was observed in the P. densiflora forest which was regenerated by forest fire about 100 years ago. However the pure old stand of P. polita had declined considerably and no advanced seedlings and supplings of P. polita were observed. The genetic structure of P. polita in the P. densiflora stand was investigated by isozyme analysis. The regenerated trees of P. polita in the P. densiflora stand had a multi-storied composition. However there was no genetic difference among the stories. The P. polita individuals growing in the different stories are considered to belong to a population holding a gene pool in common