Forest canopy-cover composition and landscape influence on bryophyte communities in Nothofagus forests of southern Patagonia

Abstract

Bryophytes (liverworts, mosses and hornworts) are one of the most diverse plant groups worldwide but one of the least studied in temperate forests from an ecological perspective. In comparison to vascular plants, bryophytes have a broader distribution and a longer altitudinal gradient, and their influence on the landscape is poorly understood. The objective was to evaluate environmental drivers that can influence bryophyte cover, richness, diversity, and nestedness in different forest canopy compositions in two typical landscapes across the natural distribution of bryophytes in Tierra del Fuego (Argentina). Three natural Nothofagus forest types (pure deciduous, pure evergreen, and mixed deciduous-evergreen) in two landscapes (coasts < 100 m.a.s.l. and mountains > 400 m.a.s.l.) were selected (N = 60 plots). In each plot, we established one transect (10 m length) to measure bryophyte cover (point-intercept method). Data were evaluated using generalized linear mixed models and multivariate analyses. The studied environmental drivers were mainly explained by the microclimate, with higher effective annual precipitation and relative air humidity in the coastal forests and higher soil moisture in the mountain forests. Greater liverwort richness was found in evergreen forests at the mountain (9 species) than at the coastal, while mosses showed higher richness in mixed deciduous-evergreen forests at the coastal (11 species) than at the mountain. However, the expected richness according to the rarefaction/extrapolation curves suggested that it is possible to record additional species, except for liverworts in pure deciduous forests on the coasts. Similarities and differences among the studied forest types and among plots of the same forest type and landscape were detected. These differences in the studied indexes (similarity that varied between 0 and 1) ranged from 0.09–0.48 for liverworts and 0.05–0.65 for mosses. Moreover, these results indicated that pure evergreen and mixed deciduous-evergreen forests presented higher moss cover (10.7% and 10.0%, respectively), mainly in the mountains than on the coast. These outputs highlight the need to explore differences at greater altitudinal ranges to achieve sustainability objectives conservation planning for bryophytes in southernmost forests.

Restoration of southern hemisphere beech (Nothofagaceae) forests: a meta‐analysis

“…Providing shelter provided the most consistent benefit identified in the meta-analyses. This shows how essential microclimatic conditions are for establishing Nothofagus seedlings, which aligns with observations that natural Nothofagus recruitment and survival is greater in medium-sized canopy gaps and microsites that provide shade and shelter and retain moisture (Read & Hill 1983;Stewart 1986;Allen 1987;Lusk 1995;Toro Manríquez et al 2018;Sola et al 2019). Some types of shelter provide added benefits such as protecting from herbivores or suppressing the growth of competitive Figure 1.…”

Association between bryophytes and seedlings in Nothofagussub‐Antarctic forests

“…; and (iii) M = mixed deciduous-evergreen forests (with a similar proportion of both species in the upper canopy). Details of forest structure and microclimatic properties of the study sites can be found in Toro Manríquez et al (2020). Also, two contrasting landscapes were analysed, where these three types of forests naturally occur: (i) coastal areas (C) near the Beagle Channel and (ii) mountainous areas (M) towards the interior of the island.…”

Projected shifts in deadwood bryophyte communities under national climate and forestry scenarios benefit large competitors and impair small species

“…Bryophytes that live on top of deadwood (epixylic bryophytes) play an important ecological role in forest ecosystems, by affecting carbon cycles and by providing habitat and shelter for invertebrates (e.g. Müller et al, 2015; Toro Manríques et al, 2020). Bryophytes are generally drought avoiders, they are highly dependent on external water, and many boreal and temperate species are known to be sensitive to relatively high temperatures (Furness & Grime, 1982).…”

“…Richardson et al, 2009; Stokland et al, 2012), and many epixylic bryophytes are further negatively affected by the more open, desiccating conditions of managed forest landscapes (e.g. Boudreault et al, 2018; Opoku‐Nyame et al, 2021; Toro Manríques et al, 2020).…”