天然沙冬青土壤种子库特征研究

Researches on Soil Seed Bank of Ammopiptanthus mongolicus

通过野外样方调查、种子鉴定及种子发芽等相结合的方式,对天然沙冬青种群种子库进行研究,以期揭示天然沙冬青土壤种子库特征及与种群更新之间的关系。研究结果显示,天然沙冬青种群土壤种子库比较丰富,平均密度为11粒/m2;种子主要存在于土壤表层,在有结皮存在的情况下,种子才有可能存在于0～2cm土层中,以下土层没有种子;沙冬青种子发芽率与土壤种子库呈负相关,种子库丰富的地方,种子的发芽率较低,这一对矛盾造成幼苗数量的稀少,进而影响天然沙冬青种群的自然更新。

This article researched on soil seed bank of Ammopiptanthus mongolicus by a combination way of quadrates survey, seed identification, germination, to reveal the feature of soil seed bank and the relationship between the soil seed banks and population regeneration. The results showed： the soil seed bank of Ammopiptanthus mongolicus was relatively rich, the average density was 11 seeds/m2 . The seed mainly present on the soil surface. It is possible that there were some seeds in 0-2 cm depth soil if crust exists, there was no seed below that. Seed germination rate and soil seed bank was negatively correlated. A place with high soil seed bank, but had low seed germination rate. This contradiction leads scarce seedling, and then impacts the population regeneration of it.