岷江干旱河谷生境恶劣，植物种群呈斑块状单物种聚集分布，研究植物斑块及斑块下土壤种子库的特征，有利于指导植被的自然恢复更新工作。选择岷江干旱河谷广泛存在的10种植物斑块，进行植物斑块特征的调查及斑块内土壤种子库的采样分析，结果表明：白刺花（Sophora davidii）、刺旋花（Convolvulus tragacanthoides）、金花蚤草（Pulicaria chrysantha）、矮探春（Jasminum humile）、川甘亚菊（Ajania potaninii）、小叶杭子梢（Campylotropis wilsonii）斑块有一定的土壤种子库库容量，土壤种子库种子密度在(890.0±282.233)/m2以上，而马鞍羊蹄甲（Bauhinia faberi）、芦苇（Phragmites australis）、竹叶草（Oplismenus compositus）斑块和裸斑的种子库库容量较小，土壤种子库种子密度分别为(437.5±260.615)/m2、(145.0±45.917)/m2、(172.5±69.567)/m2和(105.0±40.104)/m2；各植物斑块及土壤种子库中地面芽和高位芽生活型的植物占的比例较大，以禾本科（Poaceae）、豆科（Leguminosae）、菊科（Compositae）植物较多；各植物斑块瞬时种子库物种比例较大，在干旱河谷的大环境下，各植物斑块内的种子在土壤种子库中留存的时间可能均较短；马鞍羊蹄甲、芦苇和竹叶草斑块土壤种子库与相应地上植被物种组成的较低相似性（Sorensen相似性指数低于0.369）、极显著负相关性，以及较低的密度和物种丰富度，意味着这3种植物斑块依靠土壤种子库进行自然恢复更新的潜力可能比其他植物斑块更低。此外，裸斑的土壤种子库中存在一定量的种子且长期持续种子库的比例较大（占56%），裸斑具有一定的依靠土壤种子库进行植被恢复的潜力。针对具体的斑块特征，充分利用土壤种子库作为种源，促进现有种子的萌发，改善幼苗的定居环境是今后该区域植被恢复更新工作应更多关注的一种途径。另外，对马鞍羊蹄甲、芦苇、竹叶草斑块辅以适当的人为补充种源等措施也是值得考虑的植被恢复更新途径。%Plant populations often gather plaques with single species distribution due to the cruel water-lack habitat in dry valleys of Minjiang River. Understanding the characteristics of the plant patchness and the corresponding soil seed bank may help us develop the natural vegentation restoration and regeneration by using scattered plant community. However, little information has been available on it. Therefore, ten common plant patches were selected to suvery the vegentation characteristics and to sample the soil seed bank in dry valley of Minjiang River. Amounts of soil seeds (more than (890.0±282.233)/m2) were detected in Sophora davidii, Convolvulus tragacanthoides,Pulicaria chrysantha,Jasminum humile,Ajania potaninii,Campylotropis wilsonii patches. In contrast, Bauhinia faberi,Phragmites australisandOplismenus compositus patches had small size seed bank, which seed density were (437.5±260.615)/m2, (145.0±45.917)/m2, (172.5±69.567)/m2 and (105.0±40.104)/m2, respectively. Hemicryptophyte and phaenerophyte dominated both soil seed bank and the corresponding aboveground vegetation in the each vegetation patches, most of these species were Gramineae, Leguminosae and Compositae. Transient seed bank dominated the soil seed bank, which could short the retention time of seeds under the environment of the dry valley. Together with lower density and species richness, the low Sorensen’s coefficient (less than 0.369) and the significant negative correlations were observed between the soil seed bank and aboveground vegetation inBauhinia faberi,Phragmites australis andOplismenus compositus patches, implying that the lower potentation of vegentation restoration and regeneration by using the soil seed bank. In addition, there were much larger proportions (56%) of long-term persistent soil seed bank in the bare patch compared with that in other vegeatation patches, which might make the restoration be feasible. In short, we should take advantage of soil seed bank as the main seed source in the future practice of vegenation restoration and regeneration, but much attetion should be paid to the specific characteristics of each vegetation patch. Artificial supplementary seeds should be considered in the restoration and regeneration work withinBauhinia faberi,Phragmites australisandOplismenus compositus patches. Morover, promote existing seed germination and improve seedling settled environment may be also another efficient way in the future vegetation practice.
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