目前,自然和城市生态系统受到不同类型的大气沉积的影响,这会损害环境的平衡。塑料污染是生物群的主要威胁之一,包括地衣.附生地衣作为环境污染的生物指标具有价值,气候变化,和人为影响。在这项研究中,我们的目的是研究空气中微塑料沿人为污染梯度的地衣生物积累。我们对来自Cladonia和Xanthoria的地衣进行了采样,以强调地衣作为微塑料被动生物监测工具的有效性。我们选择了三个地点,AltipianidiArcinazzo的“自然遗址”,Castelporziano总统庄园的“受保护站点”和罗马市中心的“城市站点”。总的来说,我们采样了90个地衣,观察到外部塑料截留,在过氧化氢中熔化,并分析塑料截留。要验证该方法,我们计算了地衣中微塑料的回收率。特别是,在90个地衣样品中检测到253个MPs颗粒:97%是纤维,3%是碎片。整个地点的微塑料纤维数量出现了梯度,随着微塑料从自然地点(n=58)到城市地点(n=116)的积累,与空气中的微塑料纤维的长度和丰度之间存在直接关系。此外,我们发现了由地衣包裹的空气中塑料的第一个证据。平均而言,自然遗址经历了最短的纤维长度和最长的罗马中心。这两个属的微塑料积累没有差异。我们的结果表明,地衣可以有效地用于微塑料沉积的被动生物监测。在这种情况下,必须研究地衣在截留微塑料和保护原始区域中的作用。此外,考虑到空气中的微塑料对人体健康的影响以及地衣作为空气中的微塑料生物指标的有效性,他们的使用受到鼓励。
Currently, natural and urban ecosystems are affected by different types of atmospheric deposition, which can compromise the balance of the environment. Plastic pollution represents one of the major threats for biota, including lichens. Epiphytic lichens have value as bioindicators of environmental pollution, climate change, and anthropic impacts. In this study, we aim to investigate the lichen bioaccumulation of airborne microplastics along an anthropogenic pollution gradient. We sampled lichens from the Genera Cladonia and Xanthoria to highlight the effectiveness of lichens as tools for passive biomonitoring of microplastics. We chose three sites, a \"natural site\" in Altipiani di Arcinazzo, a \"protected site\" in Castelporziano Presidential estate and an \"urban site\" in the centre of Rome. Overall, we sampled 90 lichens, observed for external plastic entrapment, melt in oxygen peroxide and analysed for plastic entrapment. To validate the method, we calculated recovery rates of microplastics in lichen. Particularly, 253 MPs particles were detected across the 90 lichen samples: 97 % were fibers, and 3 % were fragments. A gradient in the number of microplastic fibers across the sites emerged, with increasing accumulation of microplastics from the natural site (n = 58) to the urban site (n = 116), with a direct relationship between the length and abundance of airborne microplastic fibers. Moreover, we detected the first evidences of airborne mesoplastics entrapped by lichens. On average, the natural site experienced the shortest fibre length and the centre of Rome the longest. No differences in microplastics accumulation emerged from the two genera. Our results indicated that lichens can effectively be used for passive biomonitoring of microplastic deposition. In this scenario, the role of lichens in entrapping microplastics and protecting pristine areas must be investigated. Furthermore, considering the impact that airborne microplastics can have on human health and the effectiveness of lichens as airborne microplastic bioindicators, their use is encouraged.