ABSTRACT The genus Eucalyptus has been widely introduced into many regions of the world outside its native range and has become invasive in some Mediterranean biomes (e.g. in southern Africa and California). In the Mediterranean Basin and Europe, eucalypts were introduced at the end of the 18th century. However, natural regeneration events in these regions are recent in time and limited in terms of affected areas, except for the Iberian Peninsula. An updated overview about the natural spread of Eucalyptus species in Italy is still lacking. This paper aims to fill this knowledge gap, using both published data and unpublished field data regarding naturalisation events, with a specific focus on Sicily. Three species have naturalised on the island: Eucalyptus camaldulensis, E. globulus and E. occidentalis. According to our data, E. camaldulensis showed a clear ‘switch’ in the past decade towards naturalisation and invasive behaviour on the pebbly shores of watercourses that have a torrential rainfall regime and erodible substrates, threatening native plant communities and species. Alluvial forests with Alnus glutinosa were found to be particularly vulnerable to E. camaldulensis invasion. This is significant because the A. glutinosa communities are a native habitat of particular conservation value and protected under the Habitats Directive 92/43. The uncontrolled spread of Eucalyptus species may represent a higher threat to native biodiversity than previously considered. The situation in Sicily could be indicative of the invasion process by eucalypts currently ongoing around the Mediterranean Basin, the management of which requires special attention, urgent action and sound choices.

中文翻译：

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桉树属的持续归化。在地中海盆地：对本地物种和栖息地的新威胁

摘要 桉树属已被广泛引入其原生范围以外的世界许多地区，并已侵入一些地中海生物群落（例如在南部非洲和加利福尼亚）。在地中海盆地和欧洲，桉树在 18 世纪末被引入。然而，除了伊比利亚半岛外，这些地区的自然再生事件在时间上是最近的，并且在受影响的地区方面是有限的。仍然缺乏关于桉树物种在意大利自然传播的最新概述。本文旨在填补这一知识空白，使用有关归化事件的已发表数据和未发表的现场数据，特别关注西西里岛。三个物种已在岛上归化：Eucalyptus camaldulensis、E. globulus 和 E. occidentalis。根据我们的数据，E. camaldulensis 在过去十年中明显地“转向”，在具有暴雨和可侵蚀基质的水道卵石岸边自然化和入侵行为，威胁着本地植物群落和物种。发现带有桤木的冲积林特别容易受到 E. camaldulensis 的入侵。这很重要，因为 A. glutinosa 群落是具有特殊保护价值的原生栖息地，受到栖息地指令 92/43 的保护。桉树物种不受控制的传播可能对本地生物多样性构成比以前认为的更大的威胁。西西里岛的情况可能表明目前正在地中海盆地周围进行的桉树入侵过程，其管理需要特别注意，