【目的】探明莫高窟优势病害昆虫仿爱夜蛾Apopestes spectrum(Esper)成虫在模拟壁画表面的运动行为,以揭示壁画损坏过程及其机理。【方法】本研究依据古代敦煌壁画制作工艺制作模拟壁画。利用扫描电镜观察了仿爱夜蛾成虫爬行足跗节的微观形态,定量分析了成虫翅面鳞粉量及其对壁画的污染程度,观测动物运动行为并系统记录了病害昆虫在90°模拟壁画表面的运动行为特征,分析了仿爱夜蛾成虫运动参数与模拟壁画表面粗糙度间的关系。【结果】仿爱夜蛾成虫主要依靠胸足的侧爪、中垫、掣爪片和微刺的协调作用在壁画表面黏附和爬行,在90°模拟壁画表面依然具有很强的爬行能力。仿爱夜蛾成虫通过调整步态实现在不同粗糙度表面的稳定爬行,壁画粗糙度决定了其是否需要扇动翅膀,以增大在垂直壁画表面稳定爬行的前进动力。【结论】仿爱夜蛾成虫爬行时的爪部接触冲击和拍翅行为均易造成壁画损坏,对于带有起甲、酥碱等病害的脆弱质壁画危害的风险更大。
【Aim】 This study aims to elucidate the creeping behavior on simulated murals of Apopestes spectrum (Esper), a dominant insect pest in Mogao Grottoes, Dunhuang, so to reveal the damage process and mechanism caused by insects to wall paintings. 【Methods】 The simulated murals were made according to the technology of ancient Dunhuang murals. The scanning electronic microscope was used to observe the microscopic morphology of A. spectrum adult crawling tarsus, the quantitative analysis was used to determine the adult wing scales and degree of pollution to murals, and the observation platform was used to record the dynamics of A. spectrum adult crawling vertically on the simulated murals. Moreover, the relationship between creeping parameters and surface roughness of murals was analyzed. 【Results】 The results showed that thoracic legs of the moth could adhere and move on mural surface by the coordination of claws, arolium, unguitractor and microtrichia, and had strong ability to creep on vertical surfaces. A. spectrum adults could creep stably on mural surface by adjusting their locomotive gait pattern. Furthermore, the roughness of murals determined whether the wing flapping was necessary for A. spectrum adults, which increased the motivation forces to make them creep stably on vertical simulated mural surfaces. 【Conclusion】 Both contact shock of claws and wings flutter of A. spectrum adults can cause damages to murals, which present more risks for wall paintings with diseases such as flaking, disruption and falling off.