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EN
The montane glades in the Polish Carpathians were created centuries ago and have lasted mainly as a result of mowing and grazing. The observed abandonment of traditional methods of tillage in the last century led to adverse changes in vegetation cover, including a decrease in floristic diversity and the disappearance of many plant species and associations. One of a rare mountain taxa in Poland is the alpine globeflower Trollius altissimus Crantz. The investigations were carried out between June and September 2014 in the Hala Długa glade (Gorce Mts.) at two 36 m2 plots: extensively grazed (P1) and unmanaged (P2). Light intensity, abundance and density of individuals and ramet clusters were significantly greater in the extensively grazed plot, whereas height of plant canopy, length of basal leaf petioles, width of leaf lamina, number and length of generative stems, number of flowers and follicles achieved higher values in the unmanaged plot. The structure of developmental stages and number of basal leaves did not differ remarkably between the studied sites. Also, the soil properties in both plots were very similar. The studies show that extensive sheep grazing has a positive influence on Trollius altissimus. In the studied locality such management contributes to the gradual spreading of this species. However, too intensive pasturage might eliminate this species as it has never been observed in any of the permanently grazed patches in the vicinity.
EN
Salix myrtilloides L. is an endangered species whose western limit of range runs through Poland. The main aim of the study was to increase the knowledge on the ecology and biology of S. myrtilloides populations in the Polesie Lubelskie region (Eastern Poland) in order to create an effective protection program. An 80% decrease in its population was found in this area. Our study was conducted to identify the mechanisms responsible for the process of withdrawal of this species from its natural stands by determining whether the processes of generative reproduction (pollen viability and germinability, seed germination ability and dynamics) in the populations occur properly and by characterizing within- and among-population genetic diversity of S. myrtilloides, using ISSR (Inter-Simple Sequence Repeat) primers. The results confirmed that S. myrtilloides pollen viability was high (84.17±8.67), and so were the seed germination ability (76% of the total number of sown seeds/24 h) and dynamics. The within-population genetic diversity was quite high for this species and the inter-population genetic variation was of medium value (ΦPT=0.148). The condition of two populations, their genetic diversity and sex ratio as well as the correctness of the investigated reproductive cycle stages altogether give prospects for their survival. It seems to be very important to start conservation involving the reintroduction and reconstruction of S. myrtilloides populations in the Polesie Lubelskie region. The proposed method for restoration of S. myrtilloides resources would be possible if ex situ cultivation and in vitro methods were used.
PL
Przedstawiono występowanie gatunków roślin chronionych, zagrożonych i rzadkich na użytkach zielonych usytuowanych w makroregionach: Pogórze Zachodniosudeckie, Sudety Środkowe i Wschodnie. Na podstawie badań florystyczno-fitosocjologicznych, przeprowadzonych w latach 2009-2014, stwierdzono dziesięć gatunków chronionych, w tym cztery taksony objęte ochroną gatunkową ścisłą. W składzie florystycznym użytków zielonych odnotowano dwa taksony podawane jako gatunki zagrożone wyginięciem na terenie Polski oraz osiem zagrożonych gatunków flory naczyniowej Dolnego Śląska o różnych kategoriach zagrożenia. Użytki zielone objęte badaniami, występujące w Sudetach Środkowych, charakteryzują się większym udziałem gatunków zagrożonych i rzadkich niż w Sudetach Wschodnich i Pogórzu Zachodniosudeckim.
EN
An important part of the landscape of the Sudetes are grassland. They account approximately 50% of agricultural area. These are most often semi-natural communities which their origin, complexity of the structure and species composition are due to human activity. Over the past decades, the disappearance of many meadow communities and related taxons are observed. Intensification of this phenomenon makes it necessary to conduct a study on the current state of grassland. The floristic and phytosociological study was carried out in the years 2009-2014 with the Braun-Blanquet method on the grassland in Sudetes Mts (the Western Sudetes Foothills, The Central Sudetes, The East Sudetes). The resulting material was analysed in terms of endangered and rare species. Evaluation of the plant species was based on the Regulation of the Minister of Environment of 9 October 2014, on the protection of species of plants. In addition, a list of endangered and rare vascular plants of Lower Silesia has been taken into account, which was developed based on the International Union for Conservation of Nature (IUNC) and supplemented by criteria and regional categories. The studies showed that in the floristic composition of part of the analysed grasslands there were 4 strictly protected species and 6 partial protected species. To the most commonly reported include: Colchicum autumnale L., reported slightly less frequently: Platanthera bifolia (L.) Rich., Dactylorhiza majalis (Rchb.) P. F. Hunt & Summerh.), Colchicum autumnale L. Occasionally the presence of Gymnadenia conopsea (L.) R. Br. subsp. conopsea, Trollius europaeus L., Iris sibirica L., Lilium martagon L., Epipactis helleborine (L.) Crantz were reported. Most of these species is placed on the endangered species list of vascular flora of Lower Silesia, as a species exposed to extinction and species with a lower risk of extinction (rare). Trollius europaeus L., Gymnadenia conopsea (L.) R. Br. subsp. conopsea. are in danger of becoming extinct. From species close to the threat but at a lower risk of extinction occurred Dactylorhiza majalis (Rchb.) P.F. Hunt & Summerh and poorly threatened - Colchicum autumnale L. and Platanthera bifolia (L.) Rich. Most of the rare and protected species was found on grassland located in the Central Sudetes, which can be associated with taking inventory more research areas (meadows and pastures), than on the Western Sudetes Foothills and in the East Sudetes.
EN
Molinietum caeruleae meadows belong to the most endangered plant communities in Central Europe, nowadays suffering due to the lack of management. The land abandonment promotes strong secondary expansion of macroforbs, sedges or willows, contributing to decrease of the species diversity. In light of these findings very interesting seems to be the evaluation of the variability of features of populations of rare meadow species. In Poland one of strictly protected plant is Gladiolus imbricatus L. It is a tuberous, clonal plant with sword-like leaves and tall stalks bearing purple flowers collected in one-sided inflorescence. The studies of spatio-temporal variability of selected features of subpopoulations of Gladiolus imbricatus were carried out in the years 2009-2011 in Kraków-Kostrze (Southern Poland) in patches of Molinietum caeruleae with different species composition. In Patch I chiefly occurred small meadow species, Patch II was prevailed by shrub willow, Patch III was dominated by tallgrowing macroforbs, Patch IV was characterized by substantial share of large-tussock grasses, while Patch V was overgrown by tall rhizomatous grass Phragmites communis. The plant canopy height and ground moisture raised from Patch I, via Patches II, III and IV, to Patch V. Moreover, in all sites the above mentioned parameters increased moderately in consecutive seasons. The decline of abundance of subpopulations observed in the consecutive years and in the successive patches might be caused by a mortality of individuals, a physical damage of tubers, as well as a prolonged dormancy of genets. The structure of developmental stages were similar in consecutive years but differed significantly among Patches. The increasing trend toward senility noted in successive sites could be an effect of lack of microsites suitable for seedling recruitment or absence of vegetative regeneration. The dimensions of leaf blades, flowering stalks and inflorescences remained similar in the subsequent seasons, but they augmented significantly in the successive patches. The length and the width of capsules did not change significantly between seasons and sites. Concluding, it might be assumed, that the perspectives for survivability of subpopulations diminish gradually from Patch I, via Patches II, III and IV to Patch V. Simultaneously, it should be pointed out that prospects for persistence in each place steadily decrease in effect of continuous deterioration of site conditions.
EN
Climate change is considered one of the greatest threats to biodiversity in future decades. Learning about the habitat preferences and geographical distributions of endangered species is critical for conservation management and planning in the context of climate change. This study investigated the effects of climate change on suitable habitat for Arborophila rufipectus Boulton, an endangered species that is endemic to southwest China. We used the known presence records for this species and a series of environmental variable layers to develop a predictive distribution model using maximum entropy modelling; this model was then used to assess the effects of future climate change on suitable habitat for this species. Our study indicated that climate change might have significant effects on suitable habitat for this species. By 2050, under a no-dispersal hypothesis, more than four-fifths of the habitat currently assessed as suitable would be lost, and the mean latitude of suitable habitat would shift northward by more than 100 kilometres. Based on this model, climate change would also aggravate habitat fragmentation. Under a full-dispersal hypothesis, all four climate trajectories developed by the Canadian Centre for Climate Modelling and Analysis (Ccma) and the Commonwealth Scientific and Industrial Research Organization (CSIRO) present similar trends: the area of suitable habitat is predicted to increase substantially, and habitat fragmentation would be mitigated under the two climate trajectories developed by the Goddard Institute for Space Studies (GISS). Finally, we offer some practical proposals for the future conservation of this endangered species.
EN
The variations in leaf traits of Taxus species in different light conditions are still poorly understood. We sampled leaves of Taxus yunnanensis W. C. Chang L. K. Fu and Taxus chinensis var. mairei (Lemée and Lév.) W. C. Cheng and L. K. Fu along an illumination gradient (full daylight, 40–60% full daylight, <10% full daylight), and analyzed how seven leaf traits and their correlations changed under different light conditions. The leaf trait that showed the greatest variation was specific leaf area (SLA) for T. yunnanensis, followed by leaf dry mass (LM) for both taxa. The smallest variation was in leaf width (LW) for both taxa. Plasticities of all leaf traits in both taxa were higher than 50%, and those of leaf area (LA), LM and SLA were greater than 80%. The light gradient was positively correlated with leaf length (LL), LM, leaf dry matter content (LDMC), and leaf length to width ratio (LWR). LW and SLA were negatively correlated with the light gradient. Analyses of relationships among leaf traits showed that LM of T. yunnanensis, T. chinensis var. mairei and both taxa was positively correlated with LL, LW, LA, LDMC, and LWR, and negatively correlated with SLA under all light conditions. We concluded that leaf traits and their relationships were affected by light conditions.
EN
Primula farinosa L. of Primulaceae family is a protected, rare and critically endangered species of Polish flora. All lowland sites of this species do not longer exist at present. The population number of the only one mountainous site discovered in 1959 in Beskid Sądecki (South Poland) is violently decreasing. The reasons for decrease in the population can be complex and associated with changes in both habitat changes and low effectiveness of propagation. In the course of the study, the population number was estimated and selected aspects of the biology of flowering of P. farinosa were assessed, phytosociological and habitat characteristics of the environment were prepared. The population amounted to 158 flowering specimens in 2011. Improper age structure of the population, characterized by a small share of juvenile plants indicates a possible regression of the population. The share of expansive species increased in the floristic composition of phytocoenosis as compared to historical sources. The assessed elements of generative propagation do not provide any grounds to suppose that the decrease of the population number is caused by disturbances in this field. High- and short-styled flowers are present in the population, a pollen is viable and new seeds are potentially able to germinate.
EN
At present Lychnothamnus barbatus (Meyen) Leonhardi belongs to the rarest species of charophytes in the world. In Europe it is classified as threatened with extinction. The problem of extinction of this species is intriguing, in particular in the context of its widespread occurrence in Europe and Asia till the last decade of the 20th century. Records of L. barbatus from Wielkopolska region (Western Poland) are know from 15 lakes. The most of them was stated in 19th and on beginning of 20th centuries. Now, this species is growing in 6 lakes, from among 2 sites are new. This study was undertaken to a) determine the abundance of L. barbatus and the co-occurring plant species at different sites in lakes, b) determine the most important ecological parameters controlling the structure communities with L. barbatus co-occurring and quantitative responses of this species. In 7 lakes (area 5.5-197 ha, depth max. 7.8-38 m, trophic state: meso-eutrophic) in western Poland the species composition and coverage of vegetation were studied at the 23 plots with L. barbatus occurrence in relation to the measured variables. Seventeen environmental parameters were measured including: depth of water, pH, conductivity, SO[4^2-], NH[4^+], NO[^3-], PO[4^3-], Na[^+], K[^+], Ca[^2+], Mg[^2+], chlorophyll a, Secchi disc visibility, colour, O[2] dissolved, saturation, total Fe during the period July-September. The DCA and CCA analyses were used to assess the relation between vegetation parameters and environmental variables. L. barbatus preferred the water rich in Ca[^+], Mg[^2+] and SO[4^2-] and with high concentrations of nutrients, especially NH[4^+] and PO[4^3-], and moderate values of electrolytic conductivity. In the studied lakes, L. barbatus occupied the separate niche. This species formed the communities in very shallow marginal zones of lakes (0.4-1.5 m) with other macrophytes like: Chara vulgaris, C. tomentosa, Potamogeton nitens, and monospecific stands on margins of steep lake slopes (4-6 m) with Chara globularis fo. hedwigii and Nitella mucronata. The process of extinction of this species seems to be related with increasing turbidity related in turn to algal blooming in lakes and with the spatial competition of vascular macrophytes, especially Ceratophyllum demersum.
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