Population Structure and Habitat Characteristics of Dicksonia sellowiana Hook. in the Sierra Madre Oriental, Mexico

Diversity and Genetic Structure of Dicksonia navarrensis (Dicksoniaceae) Populations in the Mexican Sierra Madre Oriental

“…The priority should be to categorize all populations in situ, and subsequently carry out ex situ work through the collection of spores or youngest individuals, initially in the populations of highest genetic diversity (Shah et al, 2008) such as POP1 in this study. The ecological characteristics of D. navarrensis populations (Reyes-Ortiz et al, 2019), and genetic information provided here, suggest develop strategies to conservation and management of MCF. If its habitat is conserved, D. navarrensis will be protected properly.…”

“…navarrensis distributed in the Mexican Sierra Madre Oriental were sampled. These populations were relatively close to human settlements, in an elevation interval of 1300 to 2200 m, on steep slopes of up to 70° with northeastern and northwestern orientation, and with canopy covers of 50–78% (Reyes-Ortiz et al, 2019). The distance between populations ranged from 12 to 163 km (Figure 1).…”

“…However, it must be considered that habitat loss and fragmentation in other fern species (Pleopeltis crassinervata and Polypodium rhodopleuron) did not have a strong influence on genetic diversity because it remained high; mean H E = 0.257 and 0.223, respectively (Winkler et al, 2011). In addition to habitat alteration, the density of D. navarrensis populations in the SMO is rapidly declining and geographic isolation is increasing due to illegal harvesting of individuals (Reyes-Ortiz et al, 2019). However, it is necessary to analyze other populations of D. navarrensis to establish the relationship between population size and forest fragment size in the different mountainous regions where it is distributed in Mexico, to complement the results obtained here, since the consequences of habitat reduction on the genetic diversity of species cannot be generalized (Carvalho et al, 2019;Yu et al, 2020).…”

“…Dicksonia navarrensis Hook is a tree fern species that was recently separated from D. sellowiana (Noben et al, 2017). In Mexico, its distribution is limited to the environmental conditions prevailing in the montane cloud forest (MCF) in the southeast (Chiapas, Oaxaca, and Veracruz), Pacific Coast (Guerrero), Trans-Mexican Volcanic Belt (Puebla), and Sierra Madre Oriental, in Hidalgo, Puebla, and Veracruz (Villaseñor, 2010;Reyes-Ortiz et al, 2019) between elevations of 1000 and 2300 m (Large & Braggins, 2004;Mickel & Smith, 2004). Among these regions, the Sierra Madre Oriental is considered of particular relevance because it concentrates more than 25% of the floristic richness of Mexico, in addition to presenting a great variety of ecosystems, which exhibit a wide range of environmental conditions.…”

“…Populations of D. navarrensis in the Mexican Sierra Madre Oriental, are rapidly declining, mainly as a consequence of illegal extraction of individuals, fragmentation, and land use changes (Eleutério & Pérez-Salicrup, 2009). Therefore, it is essential to determine the genetic diversity of their populations, as a first step to establish conservation strategies in this region (Reyes-Ortiz et al, 2019). It has been suggested that low levels of diversity are common in species and populations that are at risk of extinction (Wang & Guan, 2011); the disappearance of even one population implies a serious loss of genetic diversity (De Groot et al, 2012).…”