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Ecological indicator values (EIV) are a commonly used tool for assessing habitat conditions in various ecosystems. They are relatively rarely used for the analysis of epiphytic communities, which results from objective difficulties in the study of this group of organisms in full height gradient on settled trees. Windthrows provide a rare opportunity to fully analyse the biota diversity of epiphytic bryophytes and lichens. The aim of the study was to determine and compare the EIV variability for bryophytes and lichens in the vertical gradient, from terrestrial to different epiphytic exposures. The fieldworks were carried out on two windthrow areas in the Kampinos National Park (central Poland). A set of floristic lists was prepared within five distinguished parts of trees (trunk base, lower trunk, upper trunk, lower crown and upper crown) and three parts of their uproots (pit, bottom root plate and top root plate) for three species (oak, birch, pine). Ten individuals of each tree species were selected. The average values of five ecological indicator values (light, temperature, continentality, humidity and acidity) were calculated within the examined parts of trees and their uproots. The significance of differences between bryophyte and lichen EIV within same parts of trees and their uproots was checked using Wilcoxon paired test. The significance of differences of EIV calculated for bryophytes and lichens pulled together between distinguished tree and uproot parts were checked with Kruskal−Wallis or Mann−Whitney tests. Ordination of researched parts in terms of their EIV was carried out using NMDS method. The values of individual EIV obtained with the use of bryophytes and lichens for the examined parts of trees and their uproots differed significantly in most cases. The values of temperature and continentality in most cases were significantly higher for lichen, which may indicate the need for additional calibration of these indicators for these groups of organisms. The use of both groups of organisms in bioindication has increased the quantity and quality of available ecological information. The research confirmed the usefulness of ecological indicator values as a tool for analysing general habitat conditions in forest ecosystems.
Fires that are one of the most classic disturbance of plant communities have had a great impact on the development of Scots pine communities. Restoration of vegetation disturbed by fire in this type of community starts almost immediately after disturbance. The intensity of fire significantly influences the future composition of vascular plant species and also the rate of change. The aim of the study was to describe the effect of intensity of the surface fire on the forest floor vegetation response and to preliminary attempt to characterize the syndynamic processes occurring after the disturbance. The research was conducted in Scots pine forest Peucedano−Pinetum in the Kampinoski National Park (central Poland). We established 45 permanent study plots, including 17 not burnt (control) and 28 burnt ones. Each plot covered area of 100 m². On each plot at first we separated the areas which were not burnt, surface burnt and characterized by complete burnout of the organic horizon of the soil. Than we measured the thickness of this horizon. Additionally the volume of organic matter burnt within each plot was calculated. Vegetation was sampled using Londo scale in the year of fire (2015) and the year after (2016). We used DCA ordination and UPGMA classification methods. Recorded species were divided into forest and non−forest groups and additionally for trees and shrubs, and the others, containing dwarf shrub, herb, bryophyte and lichen species. The linear regression method was used to estimate the relationship between measured parameters, vegetation change and changes in the species richness of distinguished groups. Two processes of vegetation reaction were observed. The first was classified as regeneration and occurred within surface burnt plots. Its characteristic feature included the higher increase in forest species richness than in case of non−forest species. The other process was defined as secondary succession alike. It occurred on plots with highest burnout of soil organic matter horizon. The increase of richness of non−forest species predominated within it. The change between two processes is smooth and depends on the participation of area with complete burnout of soil organic horizon within plot. The results show, that more than one process of recovery of community can occur in the same site and it depends especially on the proportion of soil organic horizon area burnout.
The long−term changes of vegetation cover at the level of woodland community taking place between 1959 and 2016 on the permanent study plot located in the compartment 319 of Białowieża National Park are discussed. In 1959 two distinctive woodland community types occurring on sample plot were distinguished: subboreal mixed pine−oak forest (Serratulo−Pinetum) and hornbeam−lime forest (Tilio−Carpinetum). The phytosociological investigations, carried out almost 60 years later, revealed that in case of both communities, significant, directional changes of their floristic composition took place. Particularly high rate of change occurred in case of the phytocoenosis representing the Serratulo−Pinetum community. In 1959 it contained a full set of characteristic plant species. During the study period, this community type representing the Vaccinio−Piceetea class, was replaced by the initial form of lime−hornbeam forest belonging to the Querco−Fagetea class. Also, in case of the previous Tilio−Carpinetum association, the significant changes in the floristic composition occurred, although not as large as in case of Serratulo−Pinetum community. 60 years ago this community type contained several plant species typical for thermophilous oak forests. Nowadays, it represents a typical form of lime−hornbeam association. The changes in both community types were mainly related to the strong expansion of lime and hornbeam, which took place during the study period and involved the whole study plot. As a result, the vegetation occurring on the study plot is much more homogenous now than it was ca. 60 years ago. The maintenance of Serratulo−Pinetum phytocoenoses distinguished by a high floristic diversity calls for active protective measures in all cases where such measures are allowed and where this community type can potentially develop.
Scots pine forest are of the main economic importance to the forest management in lowland Europe. Large areas of spontaneous pine forest, including old−growths, are located on two vast dune belts of the Kampinos National Park (central Poland). These forests grow on oligotrophic sandy soils with deep groundwater level. This makes the area unique to study long−term changes in this type of pine forest communities. The aim of the work was to assess the changes in the species composition and richness of undergrowth of Scots pine forests at the beginning of the XXI century. The study was conducted on 10 permanent and 53 semi−permanent plots located within stands of Peucedano−Pinetum and Querco−Pinetum associations on both dune belts of Kampinos National Park. The fieldworks were performed in 2001 and 2002, and repeated in 2015 and 2018. Based on Ward’s cluster analysis we described five local forms of plant communities. Seven species groups were distinguished and changes in their richness assessed using one sample Wilcoxon test. Each species group included species characteristic and/or differentiating for a given set of syntaxonomical units. The results confirmed the hypothesis of gradual decrease of the total species richness. The median of species richness change was –0.308 species per year and was statistically significant. The changes were bigger within the local forms of the Querco−Pinetum association in comparison to Peucedano−Pinetum. The decrease was connected especially with dry grassland and heathland species (characteristic for syntaxons of Koelerio−Corynephoretea and Nardo−Callunetea classes) as well as with coniferous forest generalist species (characteristic for syntaxons of Vaccinio−Piceetea and Cladonio−Vaccinietalia). The results suggest that the two main processes shaping the species composition at the beginning of XXI century within pine forest located on the dune belts of Kampinos National Park may be identified as (i) fluctuation, and (ii) simplification, manifested by species richness decrease. This is probably connected with forest regeneration after past human use and disturbance.
The dynamics of plant communities is an important issue for sustainable forest management. In case of several parallel dynamic tendencies occurring within a group of research objects similar to each other, their demarcation may be difficult. The aim of the research was to check the applicability of numerical classification to distinguish the dynamic trends of plant communities on the example of multidirectional reaction of oligotrophic pine forest Peucedano−Pinetum W. Mat. (1962) 1973 to surface fire. The research was conducted in the post−fire site originated in spring 2015 in the Kampinoski National Park (central Poland). The set of 45 permanent plots was established. They differed in the degree of disturbance, measured as the share of the total burnout of the soil organic horizon. The phytosociological survey was carried out every year between 2015 and 2018, using the Londo scale. The use of cluster analysis for classification of vegetation changes requires an uniform unit for each of the variables. It was expressed as the ratio of the difference between the positions of the research plots (registered vegetation states) in the indirect space of the ordination analysis and the time elapsed between them. Thus the subject of the classification were the multidimensional changes (beta diversity) expressed in the unit of speed. The obtained material was arithmetically transformed and ordered using the PCoA method with the Bray−Curtis distance. The range of changes was calculated as differences in the plot position in three annual intervals separately for each of the four main gradients of the ordination. The 12 annual change values obtained for each of the plot were subjected to Ward classification. In order to verify the nature of the obtained clusters, collective covers of species belonging to higher syntaxones were calculated and their changes during the research period compared using the Kruskal−Wallis and Mann−Whitney tests. The significance of differences in the degree of initial disturbance was also checked. On the basis of the Ward classification, the division into five dynamic groups of plots was obtained. An analysis of the changes in the coverage of higher syntaxonomic groups revealed the existence of statistically significant differences between the clusters in 55 out of 110 possible cases. The presence of significant differences in the initial degree of disturbance by fire was also noted. The studied plot groups represent the regeneration process (A and B), pine forest regression combined with secondary succession (groups C and D) and the control group – not−disturbed pine forest (E). The cluster analysis method was proved to be an effective tool for classifying objects in terms of different tendencies of vegetation dynamic.
Montia linearis is a vascular plant originating from western North America. The expansion of this species has been observed for several decades. For the first time M. linearis was found in Europe in 1989. Further six populations were documented by 2004 within the continent: three in Poland, two in Denmark and one in Hungary. Apart from discovering a new population of M. linearis, we confirmed two out of the three previously known localities of the species in Poland. All the currently known populations of M. linearis occupied predominantly meadow habitats, especially intensively managed sites. Some individuals were also found in disturbed sites with bare soil. The studied species inhabited soils of various types with broad range of fertility as well as humidity. Montia linearis populations reached densities up to 87 individuals per 0.04 m2. The number of seeds produced by an individual was between 10 and 55 in 90% of the studied specimens, however much more fertile specimens were also observed. As the previously presented hypothesis of M. linearis dispersal with rail transport seemed not to be well supported, the connection between the M. linearis presence and cattle husbandry is considered. It is possible that the species can be transferred with living animals or manure. The species was able to survive for at least 26 years within once inhabited site. Further spread of M. linearis within Europe is highly probable. The aim of the study is to: (i) describe the current state of populations of M. linearis in Poland, (ii) provide information on habitat preferences and biology of the species, (iii) assess the invasiveness potential of M. linearis in Poland.
Cladonio−Pinetum Juraszek 1927 forest is protected in Europe as the Natura 2000 habitat. Nowadays its naturalness is often considered to be doubtful. In spite of the many research, the knowledge about ecology and dynamics of this community is still insufficient. The aim of the research is to define the stability of the community within ‘Bory Tucholskie' National Park. The site is located in the area of the best developed patches of the habitat, in north−western Poland. Two datasets of relevés were used. The first comes from published data and includes 123 relevés made in year 2000. The other comes from own fieldworks performed in 2014. Due to the high homogeneity of geology and soils of the study site, repeated chronosequence method could be used to compare both datasets. The information about herb and moss layers of all relevés was compared using DCA method. The change in community was measured as a shift in the position within the main gradient of DCA over 14−year period. It was calculated for 122 pairs of relevés. Than the model of the speed of community change was computed for the main gradient. We used two methods of calculation of duration of the lichen−rich pine forests. The first was based on the calculated ranges of distinguished associations and the other used the model of cover of species connected to Cladonio−Pinetum forest. As the speed of community change in the gradient and the distance between distinguished communities were known, the time of community duration could be computed. According to obtained results, Cladonia−Scots pine forest (Cladonio−Pinetum) and lichen rich fresh pine forest (Leucobryo−Pinetum with Cladonia) of ‘Bory Tucholskie' National Park will last for 64−109 years. This result shows, that the considered Natura 2000 habitat is unstable. It is the possible development stage within managed forest stands and active conservation is necessary where its preservation is needed.
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