Bryophyte Species Composition Research Articles

Influence of substrate age and quality on species diversity of lichens and bryophytes on stumps

Stumps from the last felling constitute a large proportion of dead wood in young managed forests. Yet, the knowledge of the diversity of stump-inhabiting organisms is poor. We studied the importance of substrate age and quality to lichen and bryophyte diversity on the cut surface of stumps in south-central Sweden. In total, we found 53 lichens and 35 bryophytes on 449 Norway spruce stumps in a forest stand chronosequence of four age classes: 4-5, 8-9, 12-13 and 16-18 years old stands. The influence of substrate age and substrate quality on species diversity differed between lichens and bryophytes. Lichen species richness was higher for age classes 2-4 compared to age class 1, whereas bryophyte richness was higher in age classes 3-4 than in 1. Further, lichen richness increased with increasing stump height and the presence of surface structural components (chairs and levels), which together with decay also influenced lichen species composition. Conversely, increasing stump height and the presence of levels decreased bryophyte richness, which in turn increased with increasing decay, surface area and number of surrounding trees and shrubs. Only decay explained differences in bryophyte species composition. Stumps in this region seem more important to overall lichen diversity, because there were on average more lichen species per stump and we only found common bryophytes but several uncommon lichens. The different responses of lichens and bryophytes to age and substrate variables indicates, however, the importance of including several organism groups in species diversity studies of dead wood.

The Rengen Grassland experiment: bryophytes biomass and element concentrations after 65 years of fertilizer application

The Rengen Grassland Experiment in Germany, established in 1941, consists of the following fertilizer treatments applied under a two cut management: control, Ca, CaN, CaNP, CaNP-KCl, and CaNP-K(2)SO(4). The aim of this study was (1) to identify effects of fertilizer application on biomass and species composition of bryophytes and (2) to investigate the impact of fertilizer application on macro- (N, P, K, Ca, Mg), micro- (Cu, Fe, Mn, Zn), and toxic (As, Cd, Cr, Pb, Ni) element concentrations in bryophyte biomass. In June 2006, Rhytidiadelphus squarrosus was the only bryophyte species recorded in the control. In treatment Ca, R. squarrosus was the dominant bryophyte species whereas Brachythecium rutabulum occurred sporadically only in a single plot of that treatment. The latter was the only bryophyte species collected in CaN, CaNP, CaNP-KCl, and CaNP-K(2)SO(4) treatments. Dry matter accumulation of bryophytes was highest in the control (180 g m(-2)) followed by Ca (46 g m(-2)), CaNP (25 g m(-2)), CaNP-KCl (15 g m(-2)), CaNP-K(2)SO(4) (9 g m(-2)), and CaN (2 g m(-2)) treatments. A negative correlation between biomass production of bryophytes and dry matter production of vascular plants was revealed up to a threshold value of 400 g m(-2). Above this limit, biomass production of bryophytes remained obviously unaffected by further increase in biomass production of vascular plants. A significant effect of treatment on As, Cd, Cr, Fe, Mn, Ni, Pb, P, Ca, Mg, K, and N concentrations was revealed. Concentrations of these elements were a function of amount of elements supplied with fertilizers. Bryophytes seem to be promising bio-indicators not only for airborne deposition of toxic element but also for fertilizer introduced as well.

Relationship of Bryophyte Occurrence to Rock Type in Upstate New York and Coastal Maine

Bryophytes are often noted for their growth on specific rock types and their value as indicator species. However, some evidence suggests that restriction of a species to specific rock types may be less rigid and could vary under different environmental conditions. We assessed richness and distribution patterns of bryophytes at 22 rock outcrop locations in upstate New York (NY) and coastal Maine (ACAD). At each location, detailed surveys were done in five replicate 5-m by 2-m plots on vertical rock faces. We report on the 194 bryophyte species found in these surveys and present detailed analyses for the 137 species that occurred at two or more of the 22 locations. In general, liverworts were less likely to be dominant within a plot than mosses. Within-site dominance and frequency of liverworts were less well correlated to larger-scale frequency (number of locations and regions of occurrence). In NY, although there was no significant difference in bryophyte richness by rock type, rare species were more often found on calcium-containing rock types. Rock type, soil influence, number of liverwort species, and region were significant correlates with bryophyte species composition patterns. The importance of rock type in explaining species composition patterns was still significant though weaker when ACAD locations were included in the analysis. This difference resulted from a higher prevalence of leafy liverwort species on calcium-containing rock types in ACAD. Our results present further evidence that apparent restrictions to specific rock types may shift depending on environmental conditions such as increased humidity and narrower temperature extremes that occur along the north Atlantic coast.

Cryptogams in Estonian Alvar Forests: Species Composition and their Substrata in Stands of Different Age and Management Intensity

Species-rich alvar forests represent a rare vegetation type in northern Europe. They grow locally on shallow soils formed on calcareous parent material. The aim of this study was to compare cryptogam species richness and composition on various substrata in alvar forests of different age and management rate. Altogether 101 bryophyte and 54 lichen species were recorded. Substratum explained species variance more than did the stand age or management intensity. Younger and older forests had a different bryophyte and lichen species composition. Decaying wood was the richest as cryptogam species substratum. It had quite a unique bryophyte composition, including a high amount of hepatics. Juniperus communis appeared to be an important substratum for cryptogam species diversity in alvar forests. Bryophyte species composition appeared to be similar on the bases of Pinus sylvestris, Betula pendula and Picea abies and different on J. communis. Most of the recorded threatened bryophyte species grew in old subnatural ...

The effects of stand structure on ground-floor bryophyte assemblages in temperate mixed forests

The effect of tree species composition, stand structure characteristics and substrate availability on ground-floor bryophyte assemblages was studied in mixed deciduous forests of Western Hungary. Species composition, species richness and cover of bryophytes occurring on the soil and logs were analysed as dependent variables. The whole assemblage and functional groups defined on the basis of substrate preference were investigated separately. Substrate availability (open soil, logs) was the most prominent factor in determining species composition, cover and diversity positively, while the litter of deciduous trees had a negative effect on the occurrence of forest floor bryophytes. Besides, bryophyte species richness increased with tree species and stand structural diversity, and for specialist epiphytic and epixylic species log volume was essential. Sapling density and light heterogeneity were influential on bryophyte cover, especially for the dominant terricolous species. Many variables of the forest floor bryophyte community can be estimated efficiently by examining stand structure in the studied region. Selective cutting increasing tree species diversity, stand structural heterogeneity and dead wood volume can maintain higher bryophyte diversity in this region than the shelter-wood system producing even-aged, monodominant, structurally homogenous stands.

樹幹着生蘇苔類の保全を目的とした孤立林のあり方の検討

Forest fragmentation has serious negative impact on epiphytic bryophytes on trees. However, few attempts have been made at their conservation because of the difficulties in identifying them. To advance their conservation, we identified what kinds of fragmented forests are effective for epiphytic bryophyte conservation. To reveal these forests, we focused on the effects of several environmental factors in fragmented forests on epiphytic bryophyte species richness, bryophyte life-forms, and the dispersal type. The study sites were 27 fragmented forests in Kyoto. Using detrended correspondence analysis (DCA), we showed that management type was significantly and strongly correlated with the DCA1 axis, whereas patch size only with the DCA2 axis. The DCA1 axis was also significantly and strongly associated with the relative species richness of three life-forms and that of asexually dispersed species, whereas the DCA2 axis with the species richness, the life-form richness, and the relative species richness of one life-forms. Considering the ecological traits of the life-forms and the dispersal type, we revealed that these environmental factors affect the bryophyte species composition through the changes or heterogeneity of moisture availability and light intensity in fragmented forests.

Bryophytes on tree trunks in natural forests, selectively logged forests and cacao agroforests in Central Sulawesi, Indonesia

Forest disturbance and transformations into agricultural land alter tropical landscapes at drastic rates. Here, we investigate bryophyte assemblages on trunk bases in natural forest, selectively logged forest and cacao agroforests that are shaded by remnants of natural forest in Central Sulawesi. Overall, bryophyte richness per site did not differ between forest types. However, mosses and liverworts reacted differently in that moss richness was lowest in cacao agroforests, whereas liverwort communities were equally rich in all forest types. In terms of cover, mosses remained unaffected while liverwort cover decreased significantly in disturbed forest. Species composition of bryophytes clearly changed in cacao agroforests as compared to natural forests and selectively logged forests. In particular some drought-sensitive species were rare or absent in cacao agroforests and were replaced by drought-tolerant ones, thus underlining the importance of microclimatic changes. Moreover, differences in bryophyte species composition between large and small trees were only pronounced in cacao agroforests, presumably due to concomitant changes in stemflow of precipitation water. In conclusion, the bryophyte assemblages of selectively logged forests and cacao agroforests were as rich as in natural forest, but species turn-over was particularly high towards cacao agroforests probably due to microclimatic changes. Maintenance of shade cover is crucial to the conservation of the drought-sensitive forest species.

Bryophyte clusters and sand dune vegetation communities

The National Vegetation Classification (NVC) is a phytosociological treatment of the British vascular and non-vascular vegetation that has been adopted widely. Since its publication between 1991 and 2000 there have been no studies which have attempted to identify clusters of bryophyte species within a site and assess their distribution in relation to NVC communities. The aim of this paper is to undertake such an approach across a variety of sand dune habitats. Detrended Correspondence Analysis (DCA) and cluster analysis utilizing percentage cover data from 97 relevés found seven bryophyte clusters distributed across the study area, which are described in terms of their bryophyte and vascular plant species composition, life-history strategies, life-forms, habitat and NVC communities. Some bryophyte clusters and NVC communities were associated strongly, while in other instances the relationships were less clear. The latter may be due to bryological gaps in the NVC data for sand dune communities and/or variation in bryophyte composition that is not correlated with changes in vascular plant communities. It is concluded that a comprehensive evaluation of the bryological quality of the NVC for habitats that are particularly important for bryophytes may be justified.

Is vascular plant species diversity a predictor of bryophyte species diversity in Mediterranean forests?

This study aimed to (i) investigate the congruence among the species composition and diversity of bryophytes and vascular plants in forests; (ii) test if site prioritization for conservation aims by the maximization of the pooled number of vascular plant species is effective to maximize the pooled number of bryophyte species. The study was performed in six forests in Tuscany, Italy. Four-hundred and twenty vascular plant species (61 of which were woody) and 128 bryophyte species were recorded in 109 plots. Despite the good predictive value of the compositional patterns of both woody plants and total vascular with respect to the compositional pattern of bryophytes, the species richness of the latter was only marginally related to the species richness of the former two. Bryophyte rare species were not spatially related to rare plant species and neither coincided with the sites of highest plant species richness. The species accumulation curves of bryophytes behaved differently with respect to those of woody plants or total vascular plants. Reserve selection analysis based on the maximization of the pooled species richness of either woody plants or total vascular plants were not effective in maximizing the pooled species richness of bryophytes. This study indicates that species diversity of vascular plants is not likely to be a good indicator of the bryophyte species diversity in Mediterranean forests.

The effects of windthrow on plant species richness in a Central European beech forest

The effects of soil disturbance caused by the uprooting of a single or a few canopy trees on species richness and composition of vascular plant species and bryophytes were examined in a temperate beech forest (Fagus sylvatica) in northern Germany. We recorded the vegetation in 57 pairs of disturbed and adjacent undisturbed plots and established a chronosequence of mound ages to study the effect of time since microsite formation on plant species richness and composition. We found significant differences in plant species richness and composition between disturbed and adjacent undisturbed plots. Species richness of both vascular plants and bryophytes was higher in the disturbed than in the undisturbed plots, but these differences were more pronounced for bryophytes. We suggest that three main factors are responsible for this differential response. The availability of microsites on the forest floor that are suitable for the recruitment of bryophytes is lower than for vascular plants. Establishment of bryophytes in disturbed microsites is favoured by a greater abundance of propagules in the close vicinity and in the soil of the disturbed microsites, as well as by a greater variety of regeneration strategies in bryophytes than in vascular plants. Time since mound formation was a major factor determining plant species richness and composition. A significant decrease in the mean number of species was found from young mounds to intermediate and old mounds. However, differences were observed between vascular plants and bryophytes in the course of changes through time in species richness and composition. A large number of exclusive and infrequent vascular plant species was observed on young mounds, among them several disturbance specialists. We suggest that the establishment of many vascular plant species was infrequent and short-lived due to unfavourable light conditions and a low abundance of propagules. By contrast, the development of a litter layer was the main reason for the decreased mean number of bryophytes on old mounds. Our study supports the view that groups of species differing in important life history traits exhibit different responses to soil disturbance.

Species diversity and species composition of epiphytic bryophytes and lichens – a comparison of managed and unmanaged beech forests in NE Germany

AbstractThe impact of forest management on the species diversity and species composition of epiphytic bryophytes and lichens in beech forests (Fagus sylvatica) of NE Germany was analysed. The investigations were carried out in one unmanaged and in one managed forest, with 45 sample plots of 400 m2each. In the sample plots, the presence of the epiphytes on 2–4 randomly chosen trees (100 trees per forest) and seven environmental variables were recorded. The total number of species and the mean lichen density per mantle area was higher in the unmanaged forest than in the managed forest. Regression analyses and DCA revealed the diameter at breast height (dbh) as the most important factor affecting the species diversity and species composition in both forest types. The dbh was positively correlated with the number of growth anomalies and with the bark roughness of the phorophytes and thus a good indicator for the habitat quality. Moreover, the light conditions had a significant impact on the species composition in both forests types and on the species diversity in the managed forest. In particular, epiphytes demanding shady conditions and a consistent humidity may suffer from the abrupt exposition to radiation and the lower humidity after logging. Species typical for the unmanaged forest and most rare species must be considered as stenoecious as they demand the shady and humid conditions of the forest interior and grow on old, large trees. With the aim of sustaining the diversity of epiphytic bryophytes and lichens, forest management should ensure the continuous occurrence of big trees above the target diameter. In addition, a single tree selection felling method should be applied to minimise strong changes in the microclimate. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Bryophyte and Lichen Diversity Under Simulated Environmental Change Compared with Observed Variation in Unmanipulated Alpine Tundra

Effects of simulated environmental change on bryophyte and lichen species richness and diversity in alpine tundra were investigated in a 5-year experiment at Latnjajaure, northern Sweden. The experiment had a factorial design including fertilisation and temperature enhancement in one meadow and one heath plant community. Responses in species richness, biodiversity, and species composition of bryophytes and lichens to experimental treatments were compared to the observed variation in six naturally occurring plant communities. The combination of fertilisation and enhanced temperature resulted in a species impoverishment, for bryophytes in the bryophyte-dominated community, and for lichens in the lichen-dominated communities, but the species composition stayed within the observed natural variation. During the course of the study, no species new to the investigated mid-alpine landscape were recorded, but that scenario is realistic within a decade when comparing with the processes seen in vascular plants.

Causes of the large variation in bryophyte species richness and composition among boreal streamside forests

Abstract:Questions: Boreal forests along small streams are bryophyte diversity hotspots because they are moist, productive and relatively high pH. Do these factors also explain the large differences in species richness and species composition found among streamside sites? Do the species of species‐poor sites represent nested subsets of the species of more species‐rich sites? How do the results apply to conservation?Location: Forests along small streams in mid‐boreal Sweden.Methods: Survey of the flora of liverworts and mosses and habitat properties, including calculation of a pH‐index based on species indicator values, in 37 sites (1000‐m2 plots).Results: The number of bryophyte species per plot ranged from 34 to 125. Neither soil moisture nor basal area of trees (a proxy for productivity) correlated significantly with species richness and composition, whereas pH‐index and cover of boulders did. Species richness and composition were more strongly correlated with pH‐index for mosses than for liverworts. The richness and composition of bryophyte species most frequently found on moist ground, stream channel margins and, most unexpected, woody debris were all more strongly associated with the pH‐index than with other habitat properties. Although species composition was significantly nested, there was still some turnover of species along the first ordination axis.Conclusions To attain high numbers of species, streamside forests need to have boulders and at least pockets with higher soil and stream‐water pH. The number of Red list species was weakly correlated with total species richness and the most species‐rich sites contained many species found more in non‐forest habitats. Hence, bryophyte conservation in streamside forests should not focus on species‐rich sites but on the quality and quantity of substrate available for assemblages of forest species that are strongly disfavoured by forestry.

Bryophyte relationships with environmental and structural variables in Tasmanian old-growth mixed eucalypt forest

The species richness and species composition of bryophytes (mosses and liverworts) was recorded at 33 sites in Tasmanian old growth mixed eucalypt forest. A total of 202 bryophyte taxa were recorded, consisting of 115 liverworts and 87 mosses. This constitutes approximately one third of the total bryophyte flora for Tasmania. Mean liverwort species richness per site was higher than moss species richness. Latitude was found to be a positive predictor in all multiple regression models of bryophyte, moss and liverwort species richness. Mean annual temperature and rainfall of the driest month were positive predictors for bryophyte and liverwort species richness. Basal area of the treefern Dicksonia antarctica Labill. was a negative predictor of liverwort species richness. Latitude, variables relating to moisture, mean annual temperature, rainfall of the driest month and basal area of Dicksonia antarctica were the most significant components in predicting variation in bryophyte, moss and liverwort species composition. There were few relationships between the variables of canopy cover and soil nutrients and bryophyte species richness and composition. Substrate variables were found to be important components in predicting variation in moss and bryophyte species composition.

Causes of the large variation in bryophyte species richness and composition among boreal streamside forests

Questions: Boreal forests along small streams are bryophyte diversity hotspots because they are moist, productive and relatively high pH. Do these factors also explain the large differences in species richness and species composition found among streamside sites? Do the species of species-poor sites represent nested subsets of the species of more species-rich sites? How do the results apply to conservation? Location: Forests along small streams in mid-boreal Sweden. Methods: Survey of the flora of liverworts and mosses and habitat properties, including calculation of a pH-index based on species indicator values, in 37 sites (1000-m2 plots). Results: The number of bryophyte species per plot ranged from 34 to 125. Neither soil moisture nor basal area of trees (a proxy for productivity) correlated significantly with species richness and composition, whereas pH-index and cover of boulders did. Species richness and composition were more strongly correlated with pH-index for mosses than for liverworts. The richness and composition of bryophyte species most frequently found on moist ground, stream channel margins and, most unexpected, woody debris were all more strongly associated with the pH-index than with other habitat properties. Although species composition was significantly nested, there was still some turnover of species along the first ordination axis. Conclusions To attain high numbers of species, streamside forests need to have boulders and at least pockets with higher soil and stream-water pH. The number of Red list species was weakly correlated with total species richness and the most species-rich sites contained many species found more in non-forest habitats. Hence, bryophyte conservation in streamside forests should not focus on species-rich sites but on the quality and quantity of substrate available for assemblages of forest species that are strongly disfavoured by forestry. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Community structure and diversity of bryophytes and vascular plants in abandoned fen meadows

We examined effects of abandonment on species diversity and species composition by comparing 21 calcareous fen meadows in the pre-alpine zone of central and northeastern Switzerland. Meadows were divided into three classes of successional stages (mown: annually mown in late summer, young fallow: 4 –15 years, and old fallow: >15 years of abandonment). In each fen, we measured litter mass in four 20 cm20 cm plots, as well as (aboveground) biomass and species density (number of species per unit area) of bryophytes and vascular plants. Bryophyte biomass was reduced in abandoned fens, whereas litter mass and aboveground biomass of vascular plants increased. Species density of both taxonomic groups was lower in abandoned than in mown fens. Young and old successional stages were not different except for bryophytes, for which old successional stages had higher species density than young stages. We used litter mass and aboveground biomass of vascular plants as covariables in analyses of variance to reveal their effects on species density of both taxonomic groups. For bryophytes, litter mass was more important than vascular plant biomass in explaining variance of species density. This indicates severe effects of burying by litter on bryophyte species density. For species density of vascular plants, both vascular plant biomass and litter mass were of similar importance in explaining the decreased species density. Canonical correspondence analyses showed that abandonment also had an effect on species composition of both bryophytes and vascular plants. However, young and old successional stages were not different indicating fast initial changes after abandonment, but slow secondary succession afterwards. Furthermore, indicator species analysis showed that there was no establishment of new species after abandonment that might dramatically alter fen communities. Re-introduction of mowing as a nature conservation strategy may thus be very promising – even for old fallows.

Bryophytes of continental salt meadows in Austria

Continental salt meadows were investigated in the 'Seewinkel', Austria, which is the most important site for this type of vegetation in Europe. Fifty-six sites were surveyed and 64 bryophyte species found, all of them mosses. A distinct group of species occurred in all of these meadows, showing only slight differences in species assemblage regarding soil type or salinity. This is in stark contrast to the vascular plant vegetation. Bryophyte species composition and, particularly, percentage cover depended mainly on the texture of the soils, the duration of wetting and only at the most extremely salty sites on the degree of salinity. Entosthodon hungaricus and Pottia heimii were the only species that were restricted to saline soils.

Management Effects on Bryophytes in Estonian Forests

Bryophyte species richness and composition of six different forest types and three different management rates was analysed in 36 Estonian forests. Analyses were done separately for six different bryophyte species groups: total species number, hepatic, hemerophobic, common, non-epigeic and epigeic species. The differences in species richness between unmanaged and moderately managed forests were significant for all species groups, while the differences between moderately and intensively managed forests were significant only for total species number, and numbers of common and non-epigeic species. Our results showed also that in comparison of unmanaged and moderately managed forests, management effect was significant for species richness of all species groups except non-epigeic species, while in comparison of moderately and intensely managed forests, management rate remained significant only for total species richness and richness of common species. Also the species composition was affected by forest management. Only the compositions of unmanaged forest types were found to be significantly different between each other. In conclusion, even moderate management eliminates a significant number of bryophyte species, and the species composition of different forest types become more similar.

Cryptogam communities on decaying deciduous wood – does tree species diversity matter?

Bryophyte and fungal communities were investigated on fallen trees representing seven deciduous tree species in a mixed near natural nemoral forest. Bryophytes were represented by 41 taxa, including several very frequent species. Of the 296 fungal species, most were recorded with very low frequency and the share of high frequent species was much lower than among the bryophytes. Species turnover was bigger in the fungal communities, compared to the bryophyte communities, and related to a higher extent to measured differences in environmental conditions. Tree species diversity was found to be an important factor for fungal species composition, while only small differences in bryophyte species composition were found between the different tree species. On the other hand bryophyte species richness showed distinct relations to tree species and microclimatic variables, a tendency which was not evident for fungal diversity. It is concluded that the two organism groups to some extent differ in their conservation demands. Thus, conservation of wood-inhabiting bryophytes requires prioritising of large, coherent forest stands in which a stable humid microclimate and a reasonable supply of dead wood is secured. Successful conservation of fungi requires that substantial amounts of dead wood are left for natural decay in a variety of natural forest environments representing different tree species, so that heterogeneity in dead wood types is secured.

Factors Influencing Bryophyte Assemblage at Different Scales in the Western Canadian Boreal Forest

This study examined bryophyte community composition in relation to microsite and microenvironmental variation at different scales in three conifer-dominated stands in the boreal forest of Alberta, Canada. We documented bryophyte assemblage on specific microsite types (physiognomic forms providing substrates for moss colonization: logs, stumps, tree bases, undisturbed patches of forest floor, disturbed patches of forest floor), and at coarser scales: mesosites (625 m2 plots within stands), and stands (10 ha). Patterns of variation in bryophyte composition arising from the microsite sampling were clearly related to microsite type and, for woody substrates, to microsite quality (decay class; hardwood vs. softwood). Microenvironment (moisture, pH, temperature, light) also had some influence on bryophyte composition of woody microsite types. Forest floor moisture, pH, and light were related to bryophyte composition of undisturbed patches of forest floor while forest floor moisture and temperature were significant correlates for disturbed forest floor. At the coarser-scale, surface moisture and forest floor moisture were related to bryophyte assemblage of mesosites; this was partially reflective of differences among stands. We conclude that bryophyte species composition in these forests is related to a hierarchy of factors including fine scale variation in the type and quality of available microsites along with microenvironmental variation at different scales. Management efforts to preserve bryophyte biodiversity will need to incorporate this complexity.