图们江下游湿地土壤种子库特征研究

The Characteristics of Soil Seed Banks in the Wetland in the Downstream Region of Tumen River

为对图们江下游湿地土壤种子库的物种组成、数量、物种多样性、相似性指数以及时空分布等特征进行分析,选取了图们江下游3个切面的河岸样地进行野外调查及选取样地采样,并采用种子萌发实验确定了土壤种子库的种类和数量.结果表明:图们江下游河流湿地种子库共有植被物种19种,种子库的密度最大为17 750粒/m2,最小为1 953粒/m2;种子库的生态优势度在0.63～0.87之间,多样性指数相对较低,其中Shannon-Wiener指数最高为2.30;种子库的垂直分布特征较为明显,其中0～5cm层的种子数量最多,各种子数量层间差异显著或极显著.此外,还研究了土壤种子库萌发随时间变化的规律,发现萌发数量随时间变化呈"S"型曲线增长.

This paper conducted researches on typical wetlands soil seed banks（SSB） in the downstream region of Tumen River and analyzed the composition,diversity and temporal and spatial distribution of SSB in three standard plots through field investigation and germinated seeds.The results showed that there are 19 species in the SSB,with species density 1953-17750/m2 and ecological dominance 0.63-0.84.The diversity index show a relatively low value,and the highest Shannon-Wiener value is 2.30.Vertical distribution demonstrated significantly obvious condition with 0-5cm having the most species.Furthermore,we studied the rules of germination of SSB changes,and got its germination number increased as a ＂S＂ curve growth.