By seed germination monitoring,transient soil seed bank of nine communities in the Baihua mountainous area of West Beijing City are analyzed.Results showed that the storage capacity of soil seed bank of different vegetation communities ranked from 97 to 1 224 seeds/m2;the number of species,from 9 to 24;Simpson index,from 74 to 0.93;Margalef index,from 1.13 to 42;and Shannon—Wiener,from 0.69 to 94.Effects of litter on soil seed bank were shown in two aspects.First,litter could intercept soil seed bank and the interception rate was between 30.8% and 77.3%.Linear correlation analysis revealed that the interception rate had a positive correlation with litter thickness.Second,litter could affect seedling growth(the experiments used mortality of seedling in three months).In forest communities,mortality of seedling in litter layer(11.9%～20.3%) was higher than that in soil layer(3.2%～8.2%).In shrub and herb communities,mortality of seedling in litter layer(2.6%～4.4%) was lower than that in soil layer(3.2%～5.1%).This indicates a significant positive correlation between mortality of seedling in litter layer and litter thickness.