干旱沙区藓类植物凭借其极强的抗旱能力在地表拓殖形成藓结皮对维持生态系统健康和稳定具有重要作用，但近年来发现其抗旱能力对气候变化、干扰和人工培养表现出极强的敏感性，并导致其生态功能的极大不确定性。对藓类植物抗旱和拓殖机理认知不足是当前对其保护和利用过程中遇到的瓶颈问题。防御警备(priming)是学术界新发现的植物防御外界胁迫的一种策略，具有应用到干旱沙区藓类植物抗旱和拓殖机理研究的可行性，但目前还没有相关报道。本项目以腾格里沙漠不同演替阶段固沙植被区藓类植物为研究对象，通过野外调查、控制实验和室内分析相结合的方法，探明藓类植物形成抗旱防御警备的激发条件和状态特征；根据干旱胁迫下，抗旱防御警备形成前后藓类植物无性繁殖能力变化及其对藓类植物自身和环境因子变化的响应规律，揭示抗旱防御警备在干旱沙区藓类植物拓殖过程中的作用及其调控机制，为干旱沙区藓类植物的保护、利用及抗旱固沙新材料的研发提供依据。

Mosses play an important role in maintaining ecosystem health and stability in arid sandy area through colonizing the soil surface and forming moss crusts by virtue of their strong anti-drought ability, but their anti-drought ability has been found to be highly sensitive to climate change, disturbance and artificial cultivation in recent years, which leads to large uncertainty of their ecological functions. Insufficient understanding of anti-drought and colonization mechanisms of mosses in arid sandy areas is the bottleneck in their protection and utilization. Defense priming is a newly recognized strategy to defend against external stresses and has great potential to be applied to the studies on anti-drought and colonization mechanisms of mosses in arid sandy areas. However, there is no related report up to date. This project takes mosses thriving in different successional stages of sand-fixing vegetation areas of the Tengger Desert as the research object. Through the combination of field investigation, controlled experiment and laboratory analysis, the triggering conditions for mosses to form anti-drought defense priming and the primed state characteristics are explored. In addition, the effects of anti-drought defense priming on moss colonization and the underlying regulation mechanisms are discovered based on the investigations of the changes in the asexual reproductive capacities of mosses before and after the formation of anti-drought defense priming, as well as their responses to the variations of mosses’ intrinsic and external environmental factors under drought stress. From above, this research project is aimed to provide theoretical bases for the protection and utilization of mosses as well as the researches in the new, anti-drought sand-fixing materials in arid sandy areas.