Study On Seedling Establishment Process Of Liliaceae Species From The Easterd Qinghai-Tibetan Plateau

The seedling was a crucial stage in the plant life cycle, Plant populations were continuated and expanded by seedling update. The process from seed germination to seed establishment was closely related to the plants update and there were not systematically studied reported about the effects of light, moisture and oxygen microenvironment to seed germination and seedling growth. Ten common Liliaceae species from the eastern Qinghai-Tibetan Plateau was used in this article. The effects of light gradients (100%,67%,35%and4%full natural sunlight) and seeds size on their seeding emergence rate, seeding survival probability and seeding establishment rate were investigated as well. The results showed that:(1)light intensity had a significant impact on seed germination and seedling establishment, which was not significant on seeding survival probability;(2)Seed size also played an important role in seedling establishment process, the small seeds had a lower seeding emergence, but a higher survival probability, which was very different from big seeds. On the different light conditions, seeding emergence rate and seeding establishment rate of seeds in different size were not same, the smallest difference was in the light conditions of L100and the biggest difference was in the light conditions of L4;(3)There were great differences between the root-shoot ratio of10species of the Liliaceae in the study under the different light conditions;(4)Under different light conditions,the relationship between root-shoot ratio and seeding establishment rate was different. Because of the important roles of seeding emergence, survival probability and establishment in community assembly, we suggested that the consideration of the seed size of different species and local lighting conditions was critical to effective natural grassland restoration and artificial grassland reconstruction.