摘要
兴安落叶松土壤种子库的支出主要有３个方面：种子萌发、动物取食和生活力丧失。兴安落叶松种子在６月份迅速萌发，占全年总前发量的９０％。７月中下旬，土壤中已经不存在有生活力的种子。在生长季初期，鼠类对种子取食率仅１％，到生长季中后期接近２０％。然而，此时幼苗发生基本结束，被食种子大部分为生活力很弱或丧失生活力者。红背是主要的食种子者。落叶松在时间上逃避了鼠类取食种子。一般，鼠类仅就地取食１０％的落叶松种子，９０％的种子为其所散布。蚁类几乎把所遇到的落叶松种子全部散布出去。鸟类与落叶松土壤种子的关系不密切．种子在６月萌发有几个有利条件：１）土壤的温度和含水量适宜；２）动物密度小，红背周密度仅０．７％（８月份达５．７％）；３）种子在土壤内留存时间短。这样，种子的死亡率就低．也便于幼苗在短暂的生长季结束前迅速生长，顺利度过严冬。
The germination, hervivore foraging and viability losing are major output of Larix gmelini seeds in the soil from seed dispersal to seedling establishment. Most of seeds germinated under the suitable condition in June, accounting for 90% of the total germination. Then,only through a short period of time, the ungerminated seeds died. The animals relevant to soil seed are as following:rodents, ants and birds. Foraging rate at early growing season is only at 1 %, about 20% at the following seasons. Clethrionomys rutilus is the major herhivorer. So,Larix gmelini escape rodent's peak period temporally. Rodents which have close relationship with Larix gmelini seed disperse 90% of seeds, only forage 10%. Ant almost disperse all met L. gmelini seeds. Birds are not closely related to soil seeds. Rapid seed germination at the beginning of the growing season should be attributed to those factors: (1) suitable soil temperature and soil moisture, otherwise, seeds will not germinate or loss their viability owing to high temperature and moisture in the soil. (2) low rodent abundance(0. 7% in May but 5. 7% in August for Clethrionomys rutilus rodent), (3) short growing season, which select seeds that germinate rapidly when the conditions are favorable in order that seedlings may be adequately established by the end of the short growth season.
出处
《生态学报》
CAS
CSCD
北大核心
1996年第5期541-547,共7页
Acta Ecologica Sinica
基金
国家自然科学基金
关键词
兴安落叶松
种子命运
老龄林
Larix gmelini, seeds fate, life history strategy, germination and mortality,herbivore forage and dispersal of seeds, old-growth forests.
