Su Yan-gui, Li Xin-Rong, Jia Rong-Liang, Pan Yan-Xie
Shapotou Desert Research and Experiment Station, Cold and Arid Regions Environmental & Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
Ying Yong Sheng Tai Xue Bao. 2007 Mar;18(3):504-8.
An investigation was made on the soil seed bank at southeast edge of Tengger Desert with moss crust under natural and artificial vegetations. The results showed that the density of soil seed bank increased with the development of moss crust, which was 3.4 times higher under natural vegetation than under 24 years old artificial vegetation. In the seed bank, a total of 12 species belonging to 6 families were identified, among which, annuals occupied more than 70%. No perennial seeds were found under artificial vegetation, but under natural vegetation, 20% of the seeds were of perennials. As for semi-shrub seeds, they occupied 20% and 10% under artificial and natural, vegetation, respectively. Under artificial vegetation, the species richness index of soil seed bank was relatively lower, being about a half of that under natural vegetation. The species diversity index of the seed bank had a slight decrease with the development of moss crust under artificial vegetation, but increased to the maximum (0. 693) under natural vegetation. The species similarity index was 1 among the seed banks under artificial vegetations, and 0.4 between those under artificial and natural vegetation. The development of moss crust increased the roughness of surface soil and improved soil environment significantly, which could have positive effects on seed entrapment and plant establishment.
对腾格里沙漠东南边缘天然植被和人工植被下有苔藓结皮的土壤种子库进行了调查。结果表明，土壤种子库密度随苔藓结皮的发育而增加，天然植被下的种子库密度是24年人工植被下的3.4倍。在种子库中，共鉴定出6科12种植物，其中一年生植物占比超过70%。人工植被下未发现多年生植物种子，而天然植被下多年生植物种子占20%。半灌木种子在人工植被和天然植被下分别占20%和10%。人工植被下土壤种子库的物种丰富度指数相对较低，约为天然植被下的一半。人工植被下，种子库的物种多样性指数随苔藓结皮的发育略有下降，而天然植被下则增至最大值（0.693）。人工植被下种子库间的物种相似性指数为1，人工植被与天然植被下种子库间的物种相似性指数为0.4。苔藓结皮的发育增加了表层土壤的粗糙度，显著改善了土壤环境，这对种子截留和植物定居具有积极影响。
