The epiphytic bryophyte succession of Buxus sempervirens forests in the Firtina Valley, Rize (North Turkiye)

Abstract

In this study, the epiphytic bryophyte succession of the Buxus sempervirens L. forests in Firtina Valley (camlihemsin-Rize, North Turkiye), one of the nine biodiversity hotspots in Turkiye, was investigated. For this purpose, a total of 60 sampling plots were taken from the live trunks of B. sempervirens trees of different ages. Twenty-nine epiphytic bryophyte species were determined (24 mosses and 5 liverworts) within the sample plots. Also, six different life form types and four different habitat affinity categories were determined. Among them, the mat type life form is in first place with 34.4% and the cortico-saxicolous species are the most common with 51.7%. Two-way indicator species analysis (TWINSPAN) classified the epiphytic bryophyte communities on B. sempervirens trunks at the second level into two main clusters (A and B) and three sub-clusters (A1, B1 and, B2). Detrended correspondence analysis (DCA) axis 1 was interpreted as gradient along the height of the epiphytic habitat (from the lower base to the upper zone) on trunks and the DCA axis 2 was interpreted as gradient of moisture (from mesic to xeric). Exsertotheca crispa (Hedw.) S. Olsson, Enroth & D. Quandt was the species with the highest index of ecological significance (IES) value on the lower bases of the aged trees. Species diversity and epiphytic cover in the upper zones were lower than in the basal and middle zones in the study area. While Metzgeria furcata, (L.) Corda, Oxyrrhynchium hians (Hedw.) Loeske, Plagiothecium nemorale (Mitt.) A.Jaeger, and Radula lindenbergiana Gottsche ex C.Hartm were only found on old trees, Ctenidium molluscum (Hedw.) Mitt. and Pseudoleskeella nervosa (Brid.) Nyholm were only found on middle-aged trees.