全球变暖增强土壤线虫群落促进外来植物成功入侵的作用及机制

With the acceleration of economic trade and social globalization, the threats of biological invasion are increasing. The deeper understanding of alien plants invasion mechanisms is required to maintain national ecological security. Existing studies of the soil fauna functioning on the alien plant successful invasion are largely focused on soil microbial communities. However, soil nematode communities, as an important component of soil ecosystem, are lacking of extensive attention. In this research, an invasive plant (Wedelia trilobata), which is known as one of the very serious invasive plants in China) and a native plant (Wedelia chinensis), which has the similar niche with the invasive plant at the invasion sites, were selected as the main research targets. Based on the theories, methods, and techniques of invasion ecology, phytoecology, global change ecology, nematode ecology and molecular bioinformatics, we intend to analyze the interactive relationship between alien plant invasion and soil nematode, explore the enhancement effect of global warming on the facilitation of soil nematode community on alien plants successful invasion and elucidate ecological mechanism of the promoting role of soil nematode community on alien plants successful invasion under global warming circumstances. The accomplishment of this research could not only enrich the invasive mechanisms of alien plants, but also provide a strong support for the prevention and control of alien invasive plants in the warming world.

随着经济贸易和社会全球化进程的加快，生物入侵所带来的危害急剧增加，为了维护国家生态安全，需要更深入解析外来植物入侵机制。目前，外来植物成功入侵的土壤生物机制研究主要集中于土壤微生物，而土壤线虫作为土壤生态系统重要组成之一，其对外来植物入侵的促进作用尚缺乏广泛关注。为了诠释全球变暖背景下土壤线虫群落对外来植物成功入侵的促进作用及其机制，我们拟以在我国暴发十分严重的外来入侵植物南美蟛蜞菊及入侵地对应相似生态位近缘植物蟛蜞菊为主要研究对象，结合入侵生态学、植物生态学、全球变化生态学、线虫生态学以及分子生物信息学等理论、方法与技术，解析外来植物成功入侵与土壤线虫群落间互作关系，阐明全球变暖增强土壤线虫群落促进外来植物成功入侵的作用及机制，诠释全球变暖背景下外来植物成功入侵的土壤线虫生态学机制。研究结果不仅可以完善外来植物成功入侵机制，还可以在实践上特别是全球变暖背景下为外来植物入侵的防控提供支持。

如何应对生物入侵带来的危害是人类社会共同面临的重大挑战。阐明外来入侵植物与入侵地土壤生物的互作关系及其对土壤生态过程的影响是科学预测并防控外来入侵植物成功入侵的关键。基于此，本项目综合野外调查采样、温室栽培试验法、现代分子生物学方法，以“世界百种恶性入侵物种”中的加拿大一枝黄花与其入侵地对应相似生态位本地植物为主要研究对象，从外来植物成功入侵与土壤线虫群落间的互作关系、全球气候变化（气候变暖与氮沉降）是如何增强土壤线虫群落对外来植物成功入侵的促进作用等方面，全面揭示全球气候变化下土壤线虫群落促进外来植物成功入侵的生态机制。项目研究结果表明，外来入侵植物通过影响土壤养分可利用性及其化学计量平衡与土壤生态过程来影响土壤线虫群落组成、结构和功能。而入侵地土壤线虫群落和生态学功能的相应改变，又营造一个更利于外来植物生长扩张的土壤微环境，进而促进外来植物的进一步入侵，增加外来入侵植物在入侵地的扩散。同时模拟全球气候变化处理下，土壤线虫促进效果更为明显，表明全球气候变化促进了土壤线虫群落与外来入侵植物的互作关系。本项目负责人及项目组成员严格遵守《国家自然科学基金条例》规定并受益于本项目的资助，项目组紧密围绕项目研究内容开展了一系列富有成效的研究工作，项目研究成果已发表SCI学术论文5篇（其中标注基金号5篇）；申请1项发明专利；培养了博士毕业研究生1名、硕士毕业研究生1名，在读硕士研究生5名。