种子大小和原位埋藏对17种高寒草甸植物种子萌发率和死亡率的影响

本研究以分布于青藏高原高寒草甸的17种植物种子为研究对象，研究种子大小和野外原位埋藏处理对种子萌发率和死亡率的影响，并探讨高寒生态系统植物种群的生态适应策略及其更新机制。研究结果表明：埋藏处理降低了冷地早熟禾（Poa crymophila）、短腺小米草（Euphrasia regelii）、甘肃马先蒿（Pedicularis kansuensis）、圆萼刺参（Morina chinensis）和钉柱委陵菜（Potentilla saundersiana）的种子萌发率，而增加了麻花艽（Gentiana straminea）和异针茅（Stipa aliena）的种子萌发率，显示了原位埋藏处理可以促进或打破某些物种的种子休眠；埋藏处理整体上降低了种子死亡率，尤其是麻花艽和细叶亚菊（Ajania tenuifolia），这表明埋藏处理有利于种子的存活，从而促进土壤种子库的形成；植物种子的萌发率和死亡率与种子大小无显著相关关系。综上所述，原位埋藏可以改变植物种子的休眠程度并减小种子的死亡率，是促进土壤种子库形成的潜在机制。

Effects of Seed Size and In-situ Burial on Seed Germination and Mortality of 17 Species of Alpine Meadow

In this study, effects of seed size and in-situ burial on seed germination for 17 species of alpine meadow were studied, and their ecological adaptation strategies and plant population regeneration mechanism were discussed. Our results showed that:the burial treatment reduced the germination proportion of Poa crymophila, Euphrasia regelii, Pedicularis kansuensis, Morina chinensis and Potentilla saundersiana, and increased the germination proportion of Gentiana straminea and Stipa aliena, indicating that in-situ burial treatment can promote or break seed dormancy of certain species;on the whole, burial treatment reduced the seed mortality rate, especially for Gentiana straminea and Ajania tenuifolia, indicating that the burial treatment was beneficial to the survival of the seeds, and thus promoted the formation of soil seed bank;there was no significant correlation of seed mass with germination proportion and seed mortality rate. In conclusion, in-situ burial can change the degree of seed dormancy and reduce seed mortality rate, and it is a potential mechanism to promote the formation of soil seed banks.