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The populations of 11 rare species of vascular plants of were found in meadow and psammophilous grasslands communities on the territory of Wildlife and Landscape Protection Area „Morasko" in Poznań. All noted species are also known as taxa endangered by extinction on the territory of the town. 1 of them - Carex arenaria - has here its only locality in Poznań. 9 others taxa (Trollius europaeus, Tetraionolobus maritimus, Achillea salicifolia, Serratula tinctoria, Scirpus maritimus, Carex cespitsa, Carex elata, Carex otrubae and Carex vesicaria) represent the category of badly vulnerable species. The last one - Achillea ptarmica - is being classified as potentially endangered species. The presence of numerous populations of rare taxa on the territory being a part of the large town makes this area very valuable as a site of protection of biodiversity.
The territory of the Wildlife and Landscape Protection Area in Morasko is a very valuable object with a seminatural landscape, covered by meadows, small paths of forests and fields. Unfortunately, the terrain is an area of intensive urbanization since about 10 years . Chosen species of genus Carex growing in the humid hay meadows have been monitored during last 8 years. In the case of populations of Carex acuta, Carex riparia and Carex acutiformis, the area covered by each species and conditions of the populations were significantly decreasing. In the case of the population of Carex panicea the area, density and condition of population were slightly increasing during the years of study. Observed effects can be connected with the changes of ground water level, which are probably the effects of influence of building-sites. The regression of populations of species of wetland ecosystems is a sign of harmful processes of simplification of landscape and decreasing of local biodiversity.
This paper presents the results of the study on the morphological variability of the populations of Carex spicata Huds., growing in different types of plant communities. The three morphotypes of C. spicata were determinated. The connections between the occurrence of the morphotypes and the type of plant community were proved.
In the city of Częstochowa a total of 122 valuable trees of 25 species from 12 families were inventoried. The most numerous group comprises trees with circumferences of natural monuments (55), followed by already registered natural monuments (25), trees with circumferences comparable to those of natural monuments and impressive trees (18 specimens each) and the category of “other trees” (6). The status of natural monuments presently found in the city of Częstochowa was confirmed. Described trees are typically native deciduous species, of which the most numerous are Acer platanoides (18 trees) and Tilia cordata (16 trees). Approximately 60% of them have circumferences from 201 to 300 cm. The health condition of surveyed trees is usually very good (84%). A total of 45 trees were selected with circumferences of natural monuments and characterised by a very good health condition, which may be proposed as worthy of protection as natural monuments.
Sedges are attractive ornamental plants, thanks to the specific structure of their inflorescences, perigynium morphology, an interesting habit and extended dates of individual phenological stages varying between species. Analyses were conducted on 15 sedge species differing in traits of their inflorescence shoots and varying in the shape and size of perigynia. Species characteristic of diverse habitats were selected so that they would meet the full spectrum of requirements of landscape architects. A nine-point scale was applied in this study, in which the decorative value of the investigated sedges was assessed. The greatest decorative value scores were recorded for Carex spicata, C. remota and C. pallescens (19 points each) and C. paniculata (18). In contrast, the lowest scores were found for C. ericetorum (12), C. digitata (13) and C. curta (14). Sedges planted in gardens are highly desirable elements of the landscape, particularly thanks to the phenotypic plasticity observed practically in all species throughout the entire vegetative season.
Flowering and fruit setting was analyzed in specimens of Chamedaphne calyculata (L.) Moench growing in a natural stand in the “Sicienko” reserve in the Drawa National Park. Seed production, seed viability and shoot rooting was investigated. It was shown that Chamaedaphne calyculata has abundant flowers but sets few fruits. Numerous seeds (even up to 87) were found in fruits; however, the percentage of developed seeds was low and ranged from 17% to 45%. The viability of developed seeds was similarly low (maximum 29%). The performed germination test showed a positive effect of stratification on the breaking of seed dormancy. Obtaining seedlings from seeds sown in vitro on agar medium was a considerable success. Shoots cut perpendicularly to the shoot axis, with a 1-cm incision on the side and treated with a rooting agent, rooted 100%. Shoots which were not treated with a rooting agent, irrespective of their having been incised or not, rooted 78%.
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