Marcin K. Dyderski

Climate change, tourism and historical grazing influence the distribution of Carex lachenalii Schkuhr – A rare arctic-alpine species in the Tatra Mts

Mountain vegetation is highly specialized to harsh climatic conditions and therefore is sensitive to any change in environment. The rarest and most vulnerable plants occurring in alpine regions are expected to respond rapidly to environmental changes. An example of such a species is Carex lachenalii subsp. lachenalii Schkuhr, which occurs in Poland on only a few isolated sites in the Tatra Mts. The aim of this study was to assess changes in distribution of C. lachenalii in the Tatra Mts over the past 50-150years and the effects of climate change, tourism and historical grazing on the ecological niche of C. lachenalii. We focused on changes in the importance of functional diversity components in shaping plant species composition. Over the past 50-150years, the elevation of the average distribution of C. lachenalii shifted about 178m upward alongside a significant prolongation of the vegetative season by approximately 20days in the last 50-60years. Species composition of plots without C. lachenalii was characterized by competition between plants, whereas on plots with C. lachenalii habitat filtering was the most important component. Our results suggest that climate change was the main factor driving upward shift of C. lachenalii. Moderate trampling enhanced horizontal spread of this plant, whereas cessation of grazing grazing caused decline of C. lachenalii. The three environmental factors studied that determined shifts in distribution of C. lachenalii may also contribute to changes in distribution of other rare mountain plant species causing changes in ecosystem functioning.

Encroachment of woody species on a drained transitional peat bog in ‘Mszar Bogdaniec’ nature reserve (Western Poland)

Abstract One of the most important threats for open peat bog ecosystems is encroachment of woody species, which causes transformation of habitat conditions and leads to retreat of specialised species. Drainage increases the rate of succession. The aim of study is the assessment of human-accelerated succession in a transitional bog. The study was conducted in ‘Mszar Bogdaniec’ nature reserve (W Poland). The structure of vegetation and tree stands was described and compared using ordination methods. Near the peat bog border, tree stands of Betula pubescens developed. Towards the middle part of the peat bog, the number, cover and height of trees decreased. The central part of the peat bog was covered by Sphagno recurvi–Eriophoretum vaginati in dryer parts and Sphagno recurvi–Eriophoretum angustifolii in wetter parts. The study showed that the successional sequence in these conditions differs from the classical bog succession scheme. Despite high propagule pressure of Pinus sylvestris, the most important woody species was B. pubescens, which performed better than other species. Erechtites hieracifolia, an alien invasive herb species, which previously was rarely recorded in bogs, appeared when the bog was dried by drainage. In this study, it reached high frequency and abundance, which shows that it may be a next serious threat to disturbed wetland ecosystems.

Natural forest remnants as refugia for bryophyte diversity in a transformed mountain river valley landscape

Riparian forests are among the most threatened ecosystem types worldwide. Their exploitation and replacement by coniferous plantations affects species pools and contributes to loss of biodiversity. We aimed to investigate bryophyte species pools within different habitat types in a transformed mountain river valley. We especially focused on the contribution of habitat types (relative to their proportional cover) to the species pool of the whole area. The study was conducted along the Czerwona Woda river - a model stream in the Stołowe Mountains National Park (SW Poland, study area: 91.2 ha) - and an example of coniferous plantations replacing natural broadleaved forest vegetation. Our study revealed the presence of 147 bryophyte species. The most valuable habitats in terms of diversity of bryophyte assemblages were remnants of the natural vegetation - broadleaved forests and streams. These habitats, constituting <5% of the study area, hosted ca 40% of the total species pool (61 and 62 species, respectively), while the species pool of Picea abies forests (92 species) was proportional to cover of this habitat type (ca 60%). Remnants of natural vegetation were hotspots of bryophyte diversity within the heavily altered landscape, and may play a future role as sources of recolonization by forest specialists. Our study also confirmed the important role of riparian areas in maintaining bryophyte species diversity at the landscape scale. The river valley studied contributes >20-fold more to the bryophyte species pool of the whole national park than indicated by its size. Thus, river valleys require special treatment - conservation based on natural restoration, and should remain reserved from wood production, as areas providing a wide range of ecosystem services.

Ecological lands for conservation of vascular plant diversity in the urban environment

Conservation of biodiversity in urban areas has become crucial to urban green area management. There are several legislative solutions for preservation of species and habitats in cities. One of them is ‘ecological lands’ – a low-restrictive form of protected areas in Poland. We aimed to assess their efficiency in vascular flora biodiversity conservation in the urban environment in Poznań (W Poland; 550,000 inhabitants). We hypothesized that ecological lands which cover <2% of the city area comprise over 50% of taxonomic diversity and over 90% of functional trait-level range of the vascular flora. Analysis of five ecological lands, which covered 1.8% of the whole city area confirmed our hypothesis. In ecological lands studied, we found 564 species of vascular plants, which is 52.9% of the whole city flora. These species belonged to 23 of 29 phytosociological classes represented in the whole city (73.9%). Functional trait distributions in ecological lands studied comprised from 95.8 to 100% of trait distributions in the flora of the whole city. Ecological lands seem to be a good way for conservation of biodiversity in urban areas. The legislative simplicity and low restrictiveness for both land management and recreational utility make ecological lands a much easier form of nature conservation which may be adapted to other cities for more efficient biodiversity management.

Habitat preferences of royal fern Osmunda regalis L. in the ‘Baszków’ nature reserve

Abstract The royal fern (Osmunda regalis L.) is a threatened species, which reaches the northeastern border of its natural range in Poland. The number of royal fern stands is decreasing due to decline of its natural habitat - alder carrs. The main aim of this paper was to compare features of stands in habitats representing different levels of anthropogenic transformation and to investigate all stands of the royal fern in the ‘Baszków’ nature reserve (3.76 ha; Krotoszyn Forest District, Poland). We distinguished four plant communities within the nature reserve: Carici elongatae-Alnetum, Molinio-Pinetum, Leucobryo-Pinetum and Pinus-Padus. In total, we found 144 royal fern specimens within the nature reserve area growing in 20 stands: 97 specimens in Carici-Alnetum (9 stands), 32 specimens in Molinio-Pinetum (4 stands) and 15 specimens along a drainage ditch (7 stands). Specimens from Carici-Alnetum had the highest proportion of sporophylles (41%), which shows the habitat preferences of the royal fern. Low proportion of sporophylles and the low number of specimens in the stands in ditches prove lower vitality of royal ferns and possibility of local extirpation in these stands. Royal fern populations in secondary habitats such as ditches and borders of forest divisions should be particularly monitored. Passive royal fern protection in the nature reserve gave positive results due to better availability of light, connected with mortality of some trees.

Response of soil mites (Acari, Mesostigmata) to long-term Norway spruce plantation along a mountain stream

During the nineteenth and twentieth centuries, coniferous monocultures were introduced, replacing natural broadleaved forests in Central Europe, mainly for economic benefits. In the mountains, Norway spruce [Picea abies (L.) H. Karst] was introduced in large areas previously covered with beech forests and also in natural riverside habitat corridors such as river valleys, despite its negative impact on the soil environment by e.g. organic matter accumulation, decrease of soil pH and changes in C/N ratio. We aimed to check how long-term Norway spruce plantations affect species richness and diversity of soil mites along a mountain river in former mixed and broadleaved forests. The study, based on 342 samples, was carried out in Stołowe Mountains National Park (SW Poland). Understory species biomass, soil pH and soil organic layer thickness significantly affected soil mite communities. Although coniferous forests did not differ from either broadleaved or mixed forests in mite density (number of individuals m−2) and species diversity (H′), they were characterized by low species richness and proportional abundance of Uropodina mites typical for broadleaved forests. In total, 4849 mites classified into 57 species were recorded from all forest types and no unique species were found in the sampled forests. Although the mite communities were dominated by the same common species (Veigaia nemorensis, Paragamasus runcatellus, Leptogamasus obesus and Trachytes aegrota), they still maintain the rare species of broadleaved forests and their high recovery potential may be used in forest conversion.

Continuum of floristic composition between two plant communities – Carici elongatae-Alnetum and Fraxino-Alnetum

Abstract One of the crucial debates in vegetation ecology is whether plant communities are discontinuous, distinguishable units or whether they change continuously. Phytosociology assumes discontinuity and its methodology requires subjective sampling during vegetation inventories. For that reason, some researchers argue that phytosociology artificially creates discontinuity among plant communities. Our aim was to assess the continuity between ash-alder riparian forest (Fraxino-Alnetum), and alder swamp forest (Carici elongatae-Alnetum), and to check whether discontinuity observed between these two plant associations is an effect of subjective sample plot choice. We conducted 57 phytosociological relevés within a regular grid covering potential sites of both plant communities. All relevés were arranged in order of decreasing relative cover of the diagnostic species for each plant association resulting in a gentle gradient, indicating a continuous transition from Fraxino-Alnetum to Carici elongatae-Alnetum. Similar results were obtained by detrended correspondence analysis. The proportion of species from the Querco-Fagetea class, typical to Fraxino-Alnetum, was decreasing with increasing proportion of species from the Alnetea glutinosae class, typical to Carici elongatae-Alnetum. This shift followed a gradient of ecological light-moisture indicator values. Our results confirmed continuous transition between two plant communities and led us to the conclusion that discontinuity resulted from the standard sampling protocol used in classical phytosociology. This protocol, however, is useful in searching for typological patterns, required for classification of plant communities, which is the main aim of phytosociology. Nevertheless, it does not provide full insight into the variability of vegetation and introduces uncertainty when trying to understand ecosystem dynamics. This uncertainty should be taken into account when phytosociological data are used for nature conservation recommendations and to draw conclusion about vegetation dynamics.

Changes in vegetation of the Mszar Bogdaniec nature reserve

Abstract Changes of vegetation in forests and wetlands require continuous monitoring and evaluation. Due to the lack of in-depth knowledge, it is still very challenging to predict and record vegetation changes. This study attempts to evaluate changes in forest and transitional bog vegetation over 14 years in the Mszar Bogdaniec nature reserve (West Poland; 21.98 ha). We described the current vegetation using 50 phytosociological relevés conducted in 2012 and 2013. Moreover, we calculated and compared ecological indices describing ecological traits of the vegetation in two different times. We also used Detrended Correspondence Analysis (DCA) to assess changes in floral composition. Most of the studied vegetation traits did not change significantly during the last 14 years. Statistically significant changes occured in the proportion of mosses and cover of the herb layer, both of which increased, as well as species richness in forest plant communities, and the cover of species from Scheuchzerio-Caricetea class in peat bog plant communities, both of which decreased. The current state of the vegetation is a result of former human activity such as drainage and planting monoculture tree stands. The observed changes during the last 14 years were fluctuations rather than direct changes. Encroachment of the woody species into transitional bog is a fluctuation, which may be secondary succession in the long-term.