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•Bryophyte species number, cover and composition depend on environmental variables.•Bryophyte species are indicators of forest types and tend to coexist.•Groups of coexisting species ...respond to environmental gradients.•Moist forests are hotspots of the diversity of forest floor bryophytes.•Databases of vegetation-plots provide limited data on bryophyte ecology.
Bryophytes are good indicators of habitat conditions and show associations with different types of forests. In this study we assessed the diversity and distribution of forest floor bryophytes across a wide gradient of Central European forests using vegetation records from the Polish Vegetation Database (PVD). We identified forest types using the Habitat Classification of the European Nature Information System (EUNIS) – the main comprehensive pan-European hierarchical classification of habitats. Based on 9258 plots containing bryophyte species and representing 20 forest types, we assessed the species number and cover, species composition of the bryophyte layer, species tendency for coexistence, and bryophyte diagnostic value for forest types. We explained the observed trends by environmental variables and bryophyte species traits to understand how bryophytes function in forest habitats.
Bryophyte species number and cover were high in forest types on moist sites, both with deciduous and coniferous tree stands. The richness and abundance of bryophyte species, as well as the species composition of the bryophyte layer depended mainly on substrate moisture, fertility and pH, as well as on the percentage cover of coniferous and deciduous tree species in the stand. Species traits which responded to environmental factors were, first of all, requirements for substrate moisture, fertility and pH. Bryophytes of closed forests and short-lived shuttle species preferred deciduous stands, while bryophytes occurring in forests as well as on open land and perennial species were associated with coniferous stands.
Bryophyte species showed a clear preference for forest types, but their fidelity was usually not high. Based on the fidelity of species, we also identified 10 groups of coexisting species which were also indicators of forest types and were dependent on environmental variables.
Forest floor bryophytes respond to environmental gradients by species number, cover and composition, and they play a diagnostic role in forest types. Our research shows the importance of databases in learning about bryophyte ecology. However, the use of vegetation data has some limitations.
Key message
The size of the structural components of the root–pit–mound complex was crucial for high moss species richness. Root plates, pits, and mounds were similar in terms of moss species ...composition, which was mostly determined by forest type.
Context
Uprooted trees may be colonized by different terricolous mosses including common species and specialists.
Aims
The main aim of the present study was to analyze the relative effects of tree uprooting on mosses.
Methods
We used the parametric ZIGLMM and GLMM models to explain the richness and abundance of the moss species and double constrained correspondence analysis (dc-CA) to analyze species composition.
Results
The size of components of RPM complexes had a positive effect on moss species richness. The species cover of mosses was positively correlated with elevation. Species richness was partly dependent on forest type and species cover on component type and age of the RPM complex. The most important factor diversifying species composition was the type of forest. Species traits were also related to forest communities.
Conclusion
Uprooted trees are worth keeping in forest community, especially large ones. Moreover, the conservation value of uprooted trees in woodlands is higher if they are dispersed in different forest types.
We have studied the diversity of bryophytes in planted Polish post‐agricultural forests dominated by the native Scots pine Pinus sylvestris and the alien (North American) red oak Quercus rubra. The ...planted sites would be suitable for a mesic coniferous forest (abbreviation: CFS) or mesic broadleaved forest (abbreviation: BFS). We analysed the structure and composition of the bryophyte assemblages in relation to forest site and substrate availability. Special attention was paid to the introduced Q. rubra as a host species for native bryophytes.
A total of 54 bryophyte species (9 liverworts and 45 mosses) were found in the 90 plots ( = phytosociological relevés, 10 × 10 m in area; 45 at each forest site) studied. DCA analysis showed that the bryophyte assemblages of the P. sylvestris–Q. rubra secondary forest community differed significantly between CFS and BFS sites; the similarity of the composition of bryophyte species was 36.8%. The substrate preferences (epigeic, epixylic, epiphytic), as well as the growth form and life form of the recorded bryophytes, also differed between CFS and BFS, while the proportion of bryophytes that had a particular life strategy was very similar.
The introduced Q. rubra was inhabited by 28 bryophyte species, including two liverworts. This tree hosted 64% of the CFS and 47% of BFS bryophyte flora and as a host for epiphytes the species successfully fulfilled the functional role of the native oaks (Q. robur and Q. petraea). Thus, the introduction of Q. rubra may contribute to the restoration of post‐agricultural forests and to the conservation of epiphytic bryophyte species. On the other hand, the negative impact of Q. rubra observed on the ground flora (including bryophytes) puts the benefits of Q. rubra for the conservation of native biodiversity in general in question.
Continuity in forest habitats is crucial for species diversity and richness. Ancient Scots pine forests are usually under forest management, which disturbs vegetation and causes differentiation in ...terms of tree stand age. To date, vegetation variability in ancient Scots pine forests has not been examined based on tree stand age classes. In the present study the continuity of a large Scots pine forest complex was investigated, and a system of sampling plots established in five tree stand age classes: initiation stands (4-10 years), young stands (20-35 years), middle-aged stands (45-60 years), pre-mature stands (70-85 years) and mature stands (95-110 years). Species composition, including vascular plants, bryophytes and lichens, on soil, tree trunks, and coarse woody debris, was analyzed. Based on existing classifications systems, forest species and ancient forest species groups were distinguished. In the studied ancient Scots pine forests the species pool and richness were relatively low, and the vegetation consisted mostly of generalist species. Cryptogams, which can grow on diverse substrates, were the most abundant species. Moreover, most species could tolerate both forest and non-forest conditions. Age class forests provided different environmental niches for species. Initiation stands were optimal for terrestrial light-demanding species, and in terms of species composition, initiation stands were most specific. Young stands were most preferred by species on coarse woody debris, and at this stage of stand maturation epiphytic species re-appeared. The oldest stands were not rich in forest specialists, i.e. species of closed forest and ancient forest species. Cryptogams of closed forests inhabited different substrates, and they were not associated only with the oldest stands. The low number of forest specialists in the oldest stands may be a general feature of acidophilus pine forests. However, it may also be a result of the lack of species sources in the vicinity of maturing pine stands. In managed forests a frequent diversity pattern is an increase in a species pool and richness after clear-cut logging. In the present study we obtained higher species pools in initiation and young stands, but richness was similar in all tree stand age classes. This resulted from taking into account species of different substrates (terrestrial, epixylous and epiphytic species) which changed their participation in the vegetation of subsequent stages of tree stand development.
•Ancient forest species have a tendency to coexist within distinctive groups.•The coexistence of ancient forest species is an indicator of high species richness.•Groups of coexisting ancient forest ...species indicate forest biodiversity hotspots.•The deciduous forests are important in determining the primary species composition.
Continuity of forest habitats is evaluated by using the indicator value of plants considered as ancient forest species or closed forest species. This is a subjectively defined group, which includes species that prefer old-growth forests. Until now, the fidelity between ancient forest species and its relation to species richness has not been assessed. Analyses were performed using resources of the Polish Vegetation Database, from which we selected relevés containing at least one species from the group of ancient forest species. Subsequently, we examined whether these species demonstrate a tendency to coexist. We established these relations using the phi coefficient of fidelity. We have distinguished eleven groups of coexisting ancient forest species (CAFS groups). Fairly common taxa in the data set constituted the majority of species forming these groups (frequency of >10%). Only one CAFS group found in the dataset was strongly localised geographically. The other groups did not demonstrate specific patterns of distribution and were recorded in relevés throughout the country. The average species richness of forests, in which at least one CAFS group was present, was significantly higher than the average in the forests, where there were no groups of CAFS found. These forests also differed significantly in the total number of ancient forest species and the number of closed forest species. We found that the coexistence of ancient forest species was an indicator of forest communities characterized by a high diversity. In all types of forests identified in the data set, at least one group of coexisting ancient forest species was identified. However, the occurrence of the CAFS groups was not equally frequent in all types of forests. CAFS groups occurred most often in the oak-hornbeam forests, species-rich beech forests and ravine forests, which are zonal types of vegetation. On the other hand, the CAFS groups were rarely found in bog Scots pine woodlands, acidophilous spruce forests, alder carrs and willow-poplar forests of lowland rivers, and these are mostly azonal vegetation types with a limited range.
CAFS groups can be used as a trans-regional indicators of forests with a high diversity of species, however, their usefulness may be limited in relation to forests found in oligotrophic habitats or azonal forest systems.
•Introduced Northern red oak efficiently colonizes European Scots pine forest.•Shrub occurrence and distance to seed source are important predictors of oak spread.•Dense moss layer favours acorn ...germination and seedling growth.•Presence of roads facilitates non-random, long-distance spread of red oak.•Continuous spread (invasion) of red oak in Scots pine monocultures is inevitable.
The effective sustainable management of introduced woody species requires understanding of the mechanisms which affect successful colonization in different forest habitats. We studied the spontaneous spread of the alien species – Northern red oak (Quercus rubra) in the Scots pine (Pinus sylvestris) forest located in Poland. We analysed the impacts of seed source distance, presence of and distance from linear structures (public and forest roads) in the landscape, as well as microhabitat diversity, on the distribution of juvenile red oaks. We also studied the effects of types of acorn deposition sites (under shrubs, within clumps of Vaccinium myrtillus, in the open), and ways of seed burial (in moss wefts, in rodent corridors) by animal seed hoarders on seed germination and seedling growth. Field data were collected in six transect lines divided into 3300 plots (1 m2 each). We found that Q. rubra efficiently colonizes Scots pine monoculture. Results of spatially explicit hierarchical generalized linear models showed that distance from acorn sources and occurrence of sparse shrub layers are the most important predictors of Q. rubra ecological success, defined as establishment of juvenile specimens. The presence of roads – potential migration corridors for avian and mammalian acorn consumers/dispersers – favoured non-random red oak spread. The “nurse effect” of native understory components on red oak seed germination and seedling growth was indicated by higher numbers of juvenile specimens as well as by higher proportions of germinated seeds noted under shrubs than in open areas (without shrubs) or within clumps of V. myrtillus. All red oaks developed from seeds buried in compact moss wefts or in spacious caches and corridors created by rodents in the moss layer, which indicated a positive “burial effect”. We conclude that microhabitats make the Scots pine forests very suitable for Q. rubra invasion. Because of the wide distribution of numerous red oak stands in European temperate forests and the presence of numerous oak seed dispersers, the continuous colonization of widespread Scots pine monocultures by Q. rubra must be expected.
Diversity loss of lichen pine forests in Poland Stefańska-Krzaczek, Ewa; Fałtynowicz, Wiesław; Szypuła, Bartłomiej ...
European journal of forest research,
08/2018, Letnik:
137, Številka:
4
Journal Article
Recenzirano
In Central Europe, deciduous forests are the dominant community type and lichen pine forests are restricted to certain areas with extremely nutrient-poor and xeric soil types. In recent decades, a ...retreat of vegetation of oligotrophic habitats has been observed in Central Europe. In this study, we assessed changes of lichen pine forests in Poland: within the main area of the range in Central Europe. We used two sets of data collected at a local and regional (nation-wide) scale. On the basis of data from semi-permanent plots, we examined changes in the structure and species composition of lichen pine forests over 33 years at the local scale (between 1975 and 2008). To compare trends at the regional scale, we used data collected in the Polish Vegetation Database (PVD). For identification of lichen pine forests we determined a group of co-occurring
Cladonia
species. We analyzed differences in species richness and vegetation structure at the regional scale in tree time periods (1) between 1951 and 1969, (2) 1970 and 1989, and (3) 1990 and 2011. We found that changes in lichen pine forests are primarily quantitative at both scales. Our results indicate that the abundance of
Cladonia
species is limited by strong competitors, i.e., vascular plants and bryophytes, which may be explained by eutrophication and climate warming. Only pine forests with a minor abundance of lichens have chances to persist in the vegetation of Central Europe, while the most valuable communities with high abundance of indicators will disappear. Though an assessment of the total decrease in the area of lichen pine forests is not possible with the available regional data, local observations indicate a large decline in the area of lichen pine forests in Central Europe. Their conservation seems to be a serious challenge, because it is difficult to provide optimal conditions for all indicators.
This paper presents the distribution of questing Ixodes ricinus ticks in suburban forest intensively visited by people. The local-scale observations conducted during a 4-year study at 99 plots (of ...100m
each) located throughout the entire area of a riparian urban forest, showed a high variation in the density of ticks from year to year. Although I. ricinus is generally permanent in the study area, spatial distribution of sample plots harbouring I. ricinus is variable, i.e. mainly random for adults and larvae, and random or clustered for nymphs. Among the most common plant species in the herb layer, there were not any species which had a statistically significant and constant impact on the occurrence of any of the development stages of I. ricinus. Also relations between the density of tick development stages and vegetation variables, including cover of the herb layer, total species number, species number of the herb layer, and percentage coverage of particular species, as well as ecological indices for light, soil moisture, reaction, and nutrients, did not show any constant and predictable pattern in subsequent years of the study. Only tree and shrub layers were found as variables positively affecting the density of ticks. Although small, suburban forests can be considered as tick-borne risk areas, it is impossible to determine in details areas of tick-borne risk.
The Las Osobowicki forest is remnant riparian woodland of the Odra valley. Floristic data were collected from circular 100m2 plots (with a radius of 5.64m) which were systematically chosen in forest ...communities. Four plant communities were determined within data set. They were represented Fagetalia order and Querco-Fagetea class. Flood prevention caused disappearance of riparian forest species, expansion of common hornbeam and Norway maple expansion and a decrease of species richness. However, spatial distribution of phytocoenoses proves the river influence on the vegetation.
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