The Study on Key Factors of Soil Seed Bank in Vegetation Restoration

The soil seed bank (SSB) is regarded as “potential genetic pool” of ground vegetation, which has functions of recalling vegetation history.In practical vegetation restoration engineering,the transplantation of alien species is the most popular method,which will influence the stability of ecological system.The soil seed bank has the advantage ofnatural regeneration,so it will become new afforestation materials.In order to enhance the feasibility of engineering application, orthogonal tests were set with three factors (the top soil thickness, the covering thickness and the number of adding seeds) and three levels.The results showed that:1) compared with blank tests,the orthogonal testshad improved species richness and density of soil seed bank significantly.2) the differences between nine plots in the number of germinated seedlings were very obvious,but in the number of arbor seedlings were not obvious.3)Overall,the Shannon-Wiener index, Simpson index and Pielou index were not high,the distribution of diversity indexes between nine plots was very even,the effect of three factors in the orthogonal testwas not obvious.4)The dominant factors of all the three factors was the topsoil thickness,for it determined the number of contained active seedsdirectly,but the specific influenceshould be determined by range analysis.