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检测了丢荒旱作地土壤种子库，其种子含量为（６８５０±３７７）·ｍ－２，共有４１种植物。其中９２．７％的种和 ７５． ８％的种子是分布在 ０～２ ｃｍ的表层中。从丢荒旱作地采挖 １０ ｃｍ深的表层土壤，以 １ｃｍ， ２ ｃｍ， ４ ｃｍ和 ８ ｃｍ 等４种不同厚度分别铺放在铅锌矿尾矿废弃地试验小区上。尽管由于铺土厚度不同，各小区所含有的土壤种子库 中的种子数量也不同，但４种铺土处理试验，其幼苗平均数量分别为每平方米８８３± ４３４，９９５± １５８，１２４２± ３２７ 和８０３±３１株，经检验差异不显著，而不铺放表土的对照区则没有幼苗生长。可见，如果仅仅是作为提供种子资源 而引入土壤种子库，则铺放 １ｃｍ的表土就已足够。然而，经过１年以后，在铺放表土厚度为１ｃｍ， ２ ｃｍ和 ４ ｃｍ处 理上的幼苗全部死亡，只有铺放 ８ ｃｍ厚度表土的小区上实现了植被恢复，共有 １５种植物成功定居，其中有 １１种开 花结果，盖度达１００％。这说明了较薄的表土不足以有效阻隔尾矿与大气的接触，减缓酸化，以及缓冲尾矿酸化的影 响，此外较薄的表土也无法提供植物根系足够的生长空间。因此，如能预先铺放一层阻隔层，如底土、馀坭、垃圾之 类，再引入土壤种子库将有助于土壤种子
A total of 41 species of plants were soil seed bank in the abandoned dryland with the seed content of (6850 ± 377) · m-2. Of which 92.7% of species and 75. 8% of the seeds are distributed in the 0 ~ 2 cm surface layer. The topsoil with depth of 10 cm was excavated from deserted and dry land and placed on the test plot of waste tailings of lead-zinc mine tailings with 4 different thicknesses of 1 cm, 2 cm, 4 cm and 8 cm, respectively. Although the number of seeds in the soil seed bank contained in each plot was also different due to the different thickness of paved soil, the average number of seedlings in the four kinds of soil treatment tests was 883 ± 434,995 ± 158,1242 ± 327 And 803 ± 31 strains, the difference was insignificant, while the control area without topsoil had no seedling growth. As can be seen, a mere 1 cm topsoil is sufficient if introduced into the soil seed bank solely for the purpose of providing seed resources. However, after one year, all the seedlings on the 1 cm, 2 cm and 4 cm of the topsoil were completely destroyed. Only 8 cm thick topsoil was planted for vegetation restoration. A total of 15 plants were successfully settled, among which There are 11 kinds of flowering results, cover up to 100%. This shows that the thinner topsoil is not enough to effectively block the contact between the tailings and the atmosphere, slow down the acidification and buffer the acidification of the tailings. In addition, the thinner topsoil can not provide sufficient root growth space for plants. Therefore, if a layer of barrier can be pre-laid, such as subsoil, waste water, garbage and the like, re-introducing the soil seed bank will help soil seed