Old-Growth Forests and Bryophyte Communities in Italy and the Broader Mediterranean Region: A Literature Review

Beginning with general references to old-growth forests and the numerous benefits that they provide at multiple levels, this review mentions the main surveys conducted in Italy to identify and characterise Italian old-growth forests and offers an overview of the state of knowledge on bryophytes of these ecosystems in Sicily. Then, it focuses on the relationship between bryophyte diversity and old-growth traits (e.g., structural characteristics, long-term continuity), as well as the potential use of bryophytes as bioindicators of forest continuity and naturalness. In this regard, studies on bryophyte floras and communities in old-growth forests were examined in detail not only for Italy but also for the broader Mediterranean region, also taking into account evidence from investigations conducted in other bioclimatic zones. The analysis shows that old-growth forests often provide refuges for rare and noteworthy taxa and host highly diverse bryophyte communities. However, it appears that in Mediterranean forests, which have been less studied than temperate and boreal forests, the influence of certain factors that are known to be important in other contexts, such as deadwood, may be comparatively less relevant. Also, bryophyte species highly related to old-growth stands or with mature and ancient trees in the Mediterranean area are reported.