梵净山栲树种群结实特征研究

STUDIES OF THE FRUIMNG HABIT OF CASTANOPSIS FARCESII IN THE FANJING MOUNTAINS

栲树结实有大小年．不论大年还是小年，都有足够的营养供开花之用．由于授粉不足和遗传败育使花的损失率极大（达９０％左右）．大小年结实的差异主要发生在种子发育期间，这差异是由于营养不足引起．大年的成熟种子产量约为小年的５倍．动物采自成熟种子，在种子雨中，小年能用于更新的有效种子很少，而在大年则剩有较多的成熟种子供更新之用．大年在栲树种群的更新中起着重要作用，而小年对种群更新作用不大．

The tructification of Castanopsis fargesii varies from year to year;hence the bumper year and the lean year. The nutrients in the tree are enough for flowering not only in the bumper ye but also in the lean year. A lot of flowers (about 90%)are shed because of pollination failure or developmental failure due to genetic defects.The amount of production of tipe seeds in the bumper year is five times ae large as that in the lean year. The difference of prodution,which is caused by the nutrient defichncy,nainly occurs in the developmental process of the seed,of the seed.Because of the predation by animals,there are few germinative seeds in the seed rain in the lean year but many in the bumper year for the regeneration of Castanopsis fargesii,It is the bumper year that Plays an important role in the regeneration