摘要
基于 6 个典型样地 180 个小样方的调查分析,对子午岭林区辽东栎(Quercus liaotungensis)种群 3 种主要林型土壤种子库及种子命运特征进行研究。结果表明:白桦-辽东栎林、辽东栎纯林和油松-辽东栎林 3 种林型土壤种子库平均储量分别为 60.19 粒/m2、87.58 粒/m2和 72.89 粒/m2;辽东栎林土壤种子密度的季节变异不大,但空间分布变异较大,其中,以油松—辽东栎林空间分布变异最强;辽东栎土壤种子库属瞬时土壤种子库,其种子丧失途径主要有萌发、虫蛀、生理死亡、动物摄食和霉变等,其中萌发是土壤种子库丧失的最主要原因;从种子大小与种子命运关系分析,辽东栎土壤种子库种子生理死亡、萌发后死亡趋向于较大粒径种子,霉变趋向于较小粒径种子,而虫蛀在各粒级种子中均有发生;辽东栎林各林型土壤种子库平均自然发芽率为 43.69 %,但幼苗存活率极低,林下实生幼苗十分匮乏,种群更新主要依赖于萌蘖。
Based on investigation data from 180 quadrats in 6 typical sample plots,the characteristics of seed bank and seed fate in three main forest types of Quercus liaotungensis population were studied. The results showed that the average seed storages of seed banks of three forest types, i.e.Ass.Betula platyphylla-Quercus liaotungensis, Ass.Quercus liaotungensis, Pinus tabulaeformis-Quercus liaotungensis, Ass. were 60.19 grains/m2, 87.58 grains/m2 and 72.89 grains/m2 respectively. Seasonal variance of soil seed density of three forest types was diminutive,but the variance of spatial distribution was evident relatively. The variance of spatial distribution of Ass.Pinus tabulaeformis-Quercus liaotungensis was the most evident among three forest types. Soil seed bank of Q.liaotungensis belonged to transient soil seed bank, in which seed loss occurred mainly in ways of germination, vermiculating, physiological death,predation and removal by animals and mildewing, among which germination was the most primary factor. In line with the relationship between seed size and seed fate of soil seed bank, bigger seeds of Q.liaotungensis tended to take the ways of physiological death and death after germination, the smaller seeds tended to take the ways of mildewing,but the vermiculating occurred in each grade of seed size. The mean spontaneous germination rate of soil seed bank of three forest types was 43.69 %. However, because the seedlings had extremely low survival rate and were greatly sparse,the natural population regeneration of Q.liaotungensis depended mainly on sprouting.
出处
《甘肃农业大学学报》
CAS
CSCD
2005年第1期7-12,共6页
Journal of Gansu Agricultural University
基金
国家"973"资助项目(2002CB111500)
关键词
辽东栎
土壤种子库
种子命运
子午岭
Quercus liaotungensis
soil seed bank
seed fate
Ziwu Mountains
