Epiphyllous Bryophytes Research Articles

Ecological niches of epiphyllous bryophytes along Afrotropical elevation gradient

Understanding multiple environmental drivers governing tropical organisms' distribution and ecological niches is crucial for predicting their responses to ongoing rapid deforestation. While macroclimatic effects via energy and water availability are well predicted, less is known about locally modulating factors such as canopy structure, light and edaphic conditions. Here we show that minimum temperatures and ambient humidity drive the abundance and richness of leaf‐inhabiting epiphyllous bryophytes across 4‐km elevation gradient on Mount Cameroon, West Africa, separating epiphyll‐rich rainforests (0–2200 m a.s.l.) from epihyll‐poor fire‐driven afromontane savanna (2300–4000 m a.s.l.). However, local factors contribute more than half to the total abundance and richness variation, either directly (light) or indirectly (edaphic conditions) via their effects on host plant composition. The most abundant epiphyllous communities occur in vertically stratified upland rainforests between 600 and 1100 m elevation, where N‐fixing tree legumes dominate. Their canopy is relatively sparse, due to nutrient‐poor soils leached by high rainfall, leaving room for the development of diverse subcanopy tree and understory shrub and herb layers with epiphyll‐rich communities. Vertically homogenous lowland rainforests on fertile soils below 500 m, with dense overstory and shaded and species‐poor understory, have less developed epiphylls, as do seasonally dry montane forests between 2000 and 2300 m, or elephant fragmented forests between 1200 and 1600 m. We conclude that high temperature and humidity together with a vertically stratified canopy support epiphylls, whereas precipitation seasonality, disturbed vegetation with unstable microclimate, or dense, unstratified canopy discourage the development of epiphyllous communities. Our study illustrates that ecological niches of epiphyllous bryophytes are shaped by a complex interplay of multiple drivers, knowledge of which is essential for more realistic predictions of the impacts of current accelerated habitat loss on species distribution and diversity changes in the tropics.

Epiphyllous Bryophyte Diversity in Lowland Rain Forest and Lowland Cloud Forest of French Guiana

Diversité des bryophytes épiphylles dans une forêt pluviale de plaine et une forêt nuageuse de plaine de Guyane française. La forêt tropicale nuageuse de plaine (LCF) est seulement connue en Guyane française mais pourrait être plus répandue dans les tropiques. Elle se distingue botaniquement de la forêt pluviale de plaine (LRF) par la diversité et la composition des groupements d'épiphytes présents dans la canopée. Pour faciliter la détection de la LCF, des indicateurs fiables au niveau du sol sont nécessaires. Une première comparaison de la diversité des bryophytes épiphylles dans le sous-bois de la LRF et de la LCF de Guyane française a révélé une richesse en espèces cinq fois plus élevée dans la LCF. L'abondance des espèces était également beaucoup plus élevée dans la LCF. L'efficacité de l'échantillonnage était d'environ 80 % dans chaque type de forêt. Six espèces (11 %) ont été trouvées dans les deux types de forêt, 43 espèces (80 %) ont été trouvées uniquement dans la LCF et cinq espèces (9 %) uniquement dans la LRF. Les espèces exclusives à la LCF n'étaient cependant pas uniques à la forêt nuageuse à une plus grande échelle. Les Lejeuneaceae Rostovzev ont contribué à 100 % de la diversité épiphylle dans la LRF et à 70 % dans la LCF. La plus faible représentation des Lejeuneaceae dans la LCF concorde avec le fait que la diversité des espèces épiphytes dans la LCF est similaire à celle des forêts montagnardes. La diversité des bryophytes épiphylles, plus que la composition des espèces, peut être un outil approprié pour la reconnaissance de la forêt nuageuse de plaine au niveau du sol, sans implication de l'escalade des arbres.

Spatial variation in human disturbances and their effects on forest structure and biodiversity across an Afromontane forest

ContextHuman disturbances can have large impacts on forest structure and biodiversity, and thereby result in forest degradation, a property difficult to detect by remote sensing.ObjectivesTo investigate spatial variation in anthropogenic disturbances and their effects on forest structure and biodiversity.MethodsIn 144 plots of 20 × 20 m distributed across a forest area of 750 km2 in Southwest Ethiopia, we recorded: landscape variables (e.g., distance to forest edge), different human disturbances, forest structure variables, and species composition of trees and epiphyllous bryophytes. We then first assessed if landscape variables could explain the spatial distribution of disturbances. Second, we analysed how forest structure and biodiversity were influenced by disturbances.ResultsHuman disturbances, such as coffee management and grazing declined with distance to forest edges, and penetrated at least a kilometer into the forest. Slope was not related to disturbance levels, but several types of disturbances were less common at higher elevations. Among human disturbance types, coffee management reduced liana cover and was associated with altered species composition of trees. The presence of large trees and basal area were not related to any of the disturbance gradients.ConclusionsAlthough most anthropogenic disturbances displayed clear edge effects, surprisingly the variation in the chosen forest degradation indices were only weakly related to these disturbances. We suggest that the intersection between edge effects and forest degradation is very context specific and relies much on how particular societies use the forests. For example, in this landscape coffee management seems to be a key driver.

Epiphyllous bryophytes in Arboretum Stradch (Ukraine)

This work done in Arboretum Stradch (Ukraine) extended the investigation of the epiphyllous bryophytes diversity in the temperate zone started by Pundiak and Michalko (2020) in Arboretum Mlyňany (Slovakia). It was identified two taxa of not typically epiphyllous bryophytes, all belonging to mosses and considered as generalists and obligate members of bryoflora of Ukraine at low risk of extinction: Brachythecium salebrosum (Hoffm. ex F. Weber & D. Mohr) Schimp. and Hypnum  cupressiforme  Hedw. As epiphylls these taxa were also the most abundant in Mlyňany. The both identified epiphylls occurred mainly on young individuals of a gymnosperm phorophyte Abies alba Mill., which grew near the trunks of 50 years lindens Tilia cordata Mill.  abundantly covered by mosses. H. cupressiforme also occurred rarely on leaves of two deciduous angiosperm phorophytes: Corylus avellana  L. and Ulmus glabra Huds. growing near trunks of 140 years oaks Quercus robur L. densely covered by the same moss species. B. salebrosum occurred also on one species of evergreen angiosperm phorophyte Rubus caesius L. (near mentioned trunks of T. cordata )  and on one species of deciduous angiosperm phorophyte Ulmus glabra Huds. (near mentioned trunks of Q. robur ), but scarcely.

Altitudinal gradient drives regional and local diversity and composition patterns of epiphyllous bryophytes in ecological refuges.

'Brejos de altitude' is an ecosystem that has been subjected to severe exploitation, leading to an intense reduction in Brazil. Understanding the patterns of bryophyte diversity and composition, particularly of specialized species such as the epiphylls, to anthropic and abiotic variables is crucial for implementing protection measures. We investigated the relationship between composition and diversity of epiphyllous bryophytes and anthropic (edge effects) and abiotic (altitude) variables at local (within each 'Brejo') and regional (set of three 'Brejos') scale. Abiotic and anthropic variables were correlated with alpha and beta diversity (decomposed into species replacement and richness differences) using GLM. Their effects on species composition were evaluated using PERMANOVA. The localities at higher elevations harboured a richer bryoflora and overall beta diversity patterns were associated with altitude and locality, which acted over different scales. Regionally, the contribution of richness differences was limited with increasing altitude. Yet, dissimilarities among localities were associated with richness differences and replacement, denoting the importance of local factors. The composition was explained by local factors interacting with the regional altitudinal gradient. Anthropic activity was significant only when interacting with local factors and altitudinal gradient. Environmental filtering associated with altitude played a more important role in shaping the diversity and composition of epiphyllous bryophytes, at both regional and local scales. Each 'Brejo' acts as an ecological refuge, harbouring part of the whole environmental gradient, and presents a unique floristic composition. Moreover, partitioning beta diversity highlighted the interplay of local and regional forces shaping diversity patterns.

First floristic study on epiphyllous bryophytes of the state Terengganu, Peninsular Malaysia

A floristic exploration was carried out of the epiphyllous bryophytes in Mount Tebu Forest Reserve, in the state of Terengganu, Peninsular Malaysia. Epiphyllous liverworts are reported for the first time from Terengganu. A total of 54 species from 18 genera and seven families of epiphyllous bryophytes were discovered, and of these, 43 liverworts are newly reported from Terengganu. The largest family is represented by Lejeuneaceae, with 44 species (81%) from 12 genera, and the largest genus is Cololejeunea, with 15 species (28%). Most of the species (43 spp., 69%) have an Indo-Pacific distribution.

Bryophytes from Caviana and Mexiana Islands, Archipelago of Marajó, Brazil

The archipelago of Marajo (Para State, Brazil) in the mouth of the Amazon river is the largest fluvial-marine complex worldwide, comprising about 2500 islands. The aim of this study was to investigate floristic and ecological attributes of the bryophyte flora of two major islands of the archipelago, Caviana and Mexiana, as a contribution to environmental conservation. In total, 572 samples were studied. The bryoflora of Caviana was represented by 89 species (39 mosses, 50 liverworts) and Mexiana by 50 species (28 mosses, 22 liverworts). Together, the two islands harbored 100 species (46 mosses and 54 liverworts). No statistical similarity was observed in the species composition between the two islands and 50 species were exclusive to Caviana while 11 species were only found on Mexiana. The latter island harbored a greater richness of mosses while liverworts were more diverse on Caviana. Epiphyllous bryophytes were exclusively found on Caviana. The floristic differences between the two islands are explained by differences in environmental conditions and vegetation cover. Drepanolejeunea lichenicola (Spruce) Steph., Eulacophyllum cultelliforme (Sull.) W.R.Buck & Ireland and Meteoridium remotifolium (Mull.Hal.) Manuel are new to the state of Para and 31 species are recorded for the first time from Marajo.

Epiphyllous bryophytes in Arboretum Mlyňany (Slovakia)

Epiphyllous bryophytes in Arboretum Mlyňany (Slovakia)

Reproductive traits as predictors of assembly chronosequence patterns in epiphyllous bryophyte metacommunities

Abstract Understanding the mechanisms underlying species assembly is a central focus of plant ecology and is crucial to revealing how plant communities are structured. However, the temporal limitations of most terrestrial plant communities preclude collection of species assembly data in a tractable time‐frame. The aim of this study is to investigate the importance of dispersal potential, as estimated by interspecific variation in sexual and asexual expression, as a predictor of patch chronosequence assembly for epiphyllous (leaf‐inhabiting) bryophytes. Secondarily, we investigate whether spatiotemporal patterns in patch turnover and compositional variation infer evidence of local (within‐patch) population processes. The frequency and distribution of 55 epiphyllous bryophytes across five leaf age classes were studied on an understorey shrub Piper grande (Piperaceae) in premontane Panamanian tropical forest. Logistical models were used to test whether interspecific variation in dispersal‐related life‐history traits predicts assembly order. Beta diversity and ordination analyses were employed to examine nestedness vs. turnover, and probe for repeatable patterns in patch chronosequence assembly, respectively. Our results emphasize the importance of dispersal potential on species assembly patterns as earlier arrivals exhibit greater probabilities of sexual and specialized asexual expression. High turnover coupled with temporal convergence in species composition also points to evidence of within‐patch biotic filtering. Synthesis. Epiphylls are locally diverse in humid tropical forests worldwide; however, the mechanisms which maintain their high local diversity are unknown. This study suggests that interspecific variation in dispersal capacity in combination with diffuse indirect effects is the principal contributor to the high alpha‐diversity of these ephemeral metacommunities.

Evaluation of six regions for their potential as DNA barcodes in epiphyllous liverworts from Thailand.

Premise of the StudyStudies on the diversity of epiphyllous bryophytes have been limited because of minute and incomplete specimens and a lack of taxonomic expertise. The recent development of the DNA barcoding approach has allowed taxon identification and species discovery of many obscure groups of organisms.MethodsWith DNA extractions from 99 samples of 16 species, we compared the efficiencies of six DNA markers (rbcL, matK, trnL‐F, psbA, ITS1, and ITS2) in their ability to amplify, using a standard set of primers, as well as their discriminatory power, using distance‐based and tree‐based approaches with nucleotide data.ResultsThe amplification success was relatively high (70–90%) with all of the markers, except for matK, which yielded no success. The barcoding gap, as calculated from the difference between inter‐ and intraspecific genetic distances, was the highest in ITS2, whereas the highest numbers of monophyletic groups were found with ITS2 and rbcL.Discussion rbcL should be used as a main barcoding marker with the addition of ITS2 for epiphyllous species. The development of DNA barcoding as a tool for quantifying species diversity will provide a rapid and reliable identification tool for epiphyllous bryophytes.

A contribution to the knowledge of epiphyllous bryophytes in Tianmushan National Nature Reserve (Zhejiang, China), with remarks on climate warming and nature conservation

Five epiphyllous liverwort species, all members of the family Lejeuneaceae, are newly reported from Tianmushan National Nature Reserve, Zhejiang Province, China. The locality constitutes the northernmost occurrence of epiphyllous bryophytes in eastern China. It is proposed that the establishment of the epiphyllous species in the reserve was the result of a recent dispersal event influenced by climate warming. The site where the species occur is increasingly impacted by ecotourism and forest ecology teaching. Limitation of teaching at the site, reduction of the number of trails and stricter conservation is recommended in order to protect the fragile local epiphyllous community.

Edge effect on epiphyllous bryophytes in Taita Hills fragmented afromontane forests

We investigated forest edge effects on the composition, abundance and species richness of epiphyllous (leaf-inhabiting) bryophytes in tropical cloud-forest fragments in the Taita Hills (Eastern Arc Mountains, Kenya). Six sample plots each of 0.04 ha (20 × 20 m) were established along a disturbance gradient extending in 200 m from the forest edge at three sites. Four leaves were collected from each phorophyte species and the diversity of epiphyllous bryophytes examined. Relative humidity and temperature readings were recorded using time-calibrated data loggers and a digital hygrometer. The epiphyllous species composition among localities and forest-edge distance classes were analysed using multivariate procedures. Overall, 1387 leaves distributed across 489 phorophytes were studied, and 95 species of bryophyte epiphylls were found in the 18 0.04-ha plots selected. The richness and distribution of epiphyllous bryophyte species did not change with the forest-edge distance, but rather depended on phorophyte species composition and (micro-) environmental variables such as sunlight exposure and spatial and dimensional canopy structure. The differences in epiphyll diversity among forest fragments were thus influenced by site-specific characteristics. Our findings suggest that management policies addressed to preserve ancient uncut stands that exhibit as much original phorophyte diversity as possible, need to be urgently achieved to protect epiphyll communities in African tropical cloud forests.

Southern thailand bryophytes II Epiphylls from the Phang-Nga area

The collection of epiphyllous bryophytes in the lowland rainforests of Phang-Nga province and in the neighbouring Phuket and Surat Thani provinces resulted in 54 liverwort and one moss species, of which 14 are new records for the bryoflora of Thailand. Epiphyllous bryophyte assemblages from nine localities are evaluated for species richness and beta diversity, as well as for their phytogeographical status.

Drought Impacts Survivorship and Reproductive Strategies of an Epiphyllous Leafy Liverwort in Central Amazonia

AbstractUnderstanding how changing precipitation patterns impact the population dynamics of Amazonian plants is necessary for predicting their long‐term survival. Most terrestrial plants are characterized by life cycles intractably slow for evaluating such demographic consequences. Due to the demands of surviving on an ephemeral substrate such as a leaf surface, epiphyllous (leaf‐inhabiting) bryophytes have some of the fastest generation times for terrestrial plants. Considering these advantages, we investigated the demographic consequences of seasonality in precipitation during one‐year of the epiphyllous bryophyte Radula flaccida Gott. (Radulaceae) in a central Amazonian rain forest. In a 1‐ha sized study area, 154 epiphyll colonies from 18 phorophytes of the understory shrub Naucleopsis ulei (Warb.) Ducke (Moraceae) were marked and colony growth, extinction, recolonization, as well as rates of sexual and asexual expression were measured in nine demographic censuses. The probability of survivorship decreased in the dry season due to the synergistic effects of both increased leaf fall (e.g., loss of occupied patches) and colony mortality on persisting leaves. Asexual expression also declined significantly during the driest months; however, sexual expression, as measured by sporophyte density, was not related to seasonality. Logistic regression probabilities also indicate a minimum threshold colony size for optimal sporophyte expression. Lower survivorship and colony growth in the dry season along with reduced sporophyte production in smaller colonies implies that both demographic stability as well as population structure of Amazonian epiphyll species may be compromised whether climate models projecting prolonged droughts for the region are accurate.

Microclimate Fluctuation Correlated with Beta Diversity of Epiphyllous Bryophyte Communities

AbstractSite‐to‐site variation in community composition, or beta diversity, is a major component of regional diversity. While many mechanisms, such as dispersal limitation and habitat heterogeneity, have been shown to affect beta diversity, interactions between habitat heterogeneity and environmental fluctuation have not been thoroughly investigated. This study uses leaf‐colonizing (epiphyllous) bryophyte communities as a model system to investigate the effects of microclimate fluctuation on beta diversity. I hypothesized that beta diversity would increase with increasing microclimate fluctuation, as niche breadth of species was reduced with increasing fluctuation. A total of 354 leaf‐colonizing bryophyte communities from 18 sites on the island of Moorea, French Polynesia were collected and identified. At each site, temperature and relative humidity were measured and converted to vapor pressure deficit (VPD). My analyses showed that beta diversity among communities on different host types tended to increase with the increasing daily range of VPD at a given site. It is possible that high fluctuation in microclimate conditions augments the differences in habitat quality among host types, resulting in greater dissimilarities among epiphyllous communities. However, host niche breadths of major epiphyllous species did not decrease with increasing VPD range. Overall, the results suggest that beta diversity may increase with environmental fluctuation, but it is not likely to be the results of reduced niche breadth as theoretically suspected.

Edge effects on understory epiphytic ferns and epiphyllous bryophytes in moist afromontane forests of Ethiopia

Abstract Most studies on edge effects in tropical forests have been conducted in landscapes with low human population density and in situations where the edges have been left unused after logging of the adjacent area. Here we studied forest margins heavily used by local farmers in a forest/agriculture mosaic landscape in Ethiopia. We compared forest structure and plant species composition across 41 forest-agriculture ecotones from 200 m out into the agricultural area to 200 m into the forest. There are strong edge effects from the edge and into the forest on canopy cover and number of stumps and apparently these forest-agricultural edges are intensively used by humans. They are penetrated by paths, beehives are found in the trees, timber of various dimensions is harvested and there is sometimes substantial cover of perennial wild (or semi-wild) crops such as coffee and spices. The number of understory epiphytic fern species as well as number of epiphyllous (i.e., growing on leaves) bryophyte species was lower at 20 m than at 75 m from the edge. The number of fern species was higher in newly created edges and thereafter they declined, which indicates an extinction debt. This pattern was not seen for the epiphyllous bryophytes. It is likely that different human management activities are responsible for many of the found edge effects besides wind and sun effects from the edge. Tropical forest margins provide important resources for people in many landscapes. It is important to understand how such use affects the biota of the forests. This study shows that there are substantial edge effects, but that the edge effects do not seem to become worse over time for epiphyllous bryophytes and only slightly so for ferns.

New methods reveal oldest known fossil epiphyllous moss: Bryiidites utahensis gen. et sp. nov. (Bryidae)

Epiphyllous bryophytes are a highly characteristic feature of many humid tropical forest ecosystems. In contrast to the extensive fossil record for the leaves of their host plants, the record is virtually nonexistent for the epiphylls themselves, despite a fossil record for mosses that begins in the Middle Carboniferous Period, 330 million years ago. Epifluorescence optical microscopy, scanning electron microscopy, and atomic force microscopy were employed to investigate an intimate association between a newly discovered epiphyllous moss and a Lauraceae plant host from the middle Cretaceous. We describe the oldest fossil specimen of an epiphyllous moss, Bryiidites utahensis gen. et sp. nov., identified from an individual specimen only 450 µm long, situated on an approximately one millimeter square fossil leaf fragment. The moss epiphyll is exquisitely preserved as germinating spores and short-celled protonemata with transverse and oblique cross-walls closely matching those of extant epiphyllous mosses on the surface of the plant-leaf hosts. The extension of the epiphyll record back to the middle Cretaceous provides fossil evidence for the appearance of epiphyllous mosses during the diversification of flowering plants, at least 95 million years ago. It also provides substantive evidence for a tropical maritime climate in central North America during the middle Cretaceous.

Fine‐scale changes in connectivity affect the metapopulation dynamics of a bryophyte confined to ephemeral patches

Summary1. We test how fine‐scale (≤ 400 m2) connectivity to conspecifics influences metapopulation dynamics using a field experiment in central Amazonia with the epiphyllous (i.e. leaf‐inhabiting) bryophyte Radula flaccida Gott. (Radulaceae). This is a natural model system with spatially structured ephemeral patches at the leaf and phorophyte scale.2. The aim was to test how the rates of leaf colonization, local abundance, growth and extinction of bryophytes from both leaves and host phorophytes were affected by experimentally manipulated variation in connectivity to conspecifics. We also investigated the relative importance of local stochastic extinctions and deterministic extinctions at both spatial scales.3. Approximately 3500 leaves on 70 phorophytes were censused six times over a 15‐month period by utilizing a repeated block design with control, positive control and three pulse‐style reduction treatments, which varied in connectivity to surrounding conspecifics.4. An increase in stochastic extinction events was only accompanied by a reduction in colonization in the treatment in which focal and neighbouring phorophytes within the 400 m2 plots were experimentally denuded of their natural populations, suggesting that epiphyllous cryptogams are subject to fine‐scale (within phorophyte) rescue effects. Negative density‐dependent growth was also detected in within‐leaf population dynamics, suggesting that resource limitation or intraspecific competition influences local population growth. Finally, stochastic extinctions from viable leaves occurred with nearly the same frequency as deterministic events (e.g. leaf fall), whereas at the phorophyte scale only stochastic extinctions were observed.5. Synthesis. The experiment demonstrates that rescue effects occur at fine scales even for vagile plant taxa, such as cryptogams, which may inhabit spatially isolated substrates characterized by turnover rates as fast as their own population dynamics. Furthermore, the results highlight the importance of quantifying both stochastic and deterministic extinction modes, as underestimating either of these parameters leads to over optimistic projections of future metapopulation size.

Epiphyllous bryophytes in the Appalachian Plateau of Kentucky and Tennessee, U.S.A

Epiphyllous bryophytes are poorly documented for temperate eastern North America. Ten liverwort taxa and one moss species are reported as epiphylls on Rhododendron maximum from the Appalachian Plateau (Fentress County, Tennessee, and Menifee County, Kentucky). The Kentucky localities represent the northernmost documented sites for bryophyte epiphylls in eastern North America. Three North American liverwort endemics, Lejeunea ruthii, Leucolejeunea clypeata, and Radula obconica, and the moss, Platygyrium repens, are newly reported as epiphylls. Colony size ranged from <0.1 mm to 20 mm in diameter. Host plant leaf coverage of epiphylls was as high as 15%. A quantitative study at one locality showed 0% of one-year-old host leaves supported bryoepiphylls with 8.9% of two and 13.3% of three-year-old leaves supporting epiphylls. The frequency and northern limits of bryoepiphylly in eastern North America are likely well underestimated.

Diversity and Rarity of Epiphyllous Bryophytes in a Superhumid Tropical Lowland Forest of Chocó-Colombia

Plant rarity is considered a useful predictor of the extinction risk of species. However, apparent rarity can emerge from incomplete data sets or incorrect sampling. Epiphyllous bryophytes are a poorly collected and taxonomically complicated group, with incompletely known distribution patterns. In this paper we explore the diversity patterns and meso- and micro-habitat specialization of common and rare epiphyllous bryophyte species, and evaluate the threat status of Aphanolejeunea gracilis, Leptolejeunea tridentata, and Otolejeunea schnellii. Epiphylls were collected from 240 samples (10 ×10 cm) in 30 plots of 5 ×5 m in superhumid lowland forest of the Chocó, Colombia. Our results indicate that epiphyll diversity and species composition is similar among palm and non-palm leaves. Disturbance had a negative effect on epiphyll cover, species richness, and diversity of rare species. Data on rare species did not correlate with global or national red lists, indicating that detailed surveys are necessary to accurately assess the threat status of “rare” species.