不同治理措施下入侵植物的土壤遗留效应对继发性入侵的影响、机制和生态后果

入侵植物的治理成效是关乎生态安全的重要内容。目前，多种入侵植物共存的现象已经非常普遍，导致治理目标入侵植物后，非目标入侵植物占据空的生态位，形成继发性入侵，再次威胁生态安全。已有研究推断入侵植物治理后的土壤遗留效应是驱动继发性入侵的关键因素。但是，治理措施往往会对土壤理化性质和微生物群落产生干扰，导致我们对“不同治理措施下入侵植物的土壤遗留效应对继发性入侵的影响、机制和生态后果”还知之甚少。本项目采用野外调查和同质园实验，结合土壤理化分析和微生物测定，（1）以恶性入侵植物加拿大一枝黄花为对象，研究火烧、除草剂和人工拔除对其土壤遗留效应的干扰；（2）以与加拿大一枝黄花常常共存的入侵植物为对象，研究土壤遗留效应对继发性入侵的影响；（3）以本地常见植物为对象，研究继发性入侵对本地植物群落恢复的影响。研究结果有助于揭示不同治理措施下继发性入侵的植物种类、发生机制和生态危害，完善入侵植物防治理论。

Effective management of invasive plants has always been a key part of ecological security. To date, the coexistence of invasive plants is very common. This may lead to an increase in abundance of non-target invasive plants following management of targeted invasive plants. This phenomenon is termed as secondary invasion, threatening the ecological security once again. Previous studies indicated that the soil legacy effect of invasive plant after management is the critical factor in driving the secondary invasion. However, different remove methods often have different impacts on soil physical and chemical properties, as well as soil microorganisms. There is little known about how soil legacy effects under different remove methods affect secondary invasion, and what is the potential mechanism and ecological damage. In this proposal, we will firstly examine the effects of fire, herbicide and clear-cutting on soil legacy effect of invasive plant Solidago canadensis. Then, we will explore how these soil legacy effects influence secondary invasion of other invasive plant species that often coexist with Solidago canadensis. Finally, we will evaluate the impact of these secondary invasions on the recovery of local plant communities. To fulfil these targets, we will conduct field surveys and common garden experiments, measure soil physical and chemical properties, and sequence soil fungal and bacteria communities. The results of this study are helpful to reveal the plant species, potential mechanism and ecological damage of secondary invasion under different remove methods, and to improve the theory of prevention and control of invasive plants.