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The study is focused on evaluating changes in the presence of alien species in ruderal vegetation. Two datasets comprising phytosociological relevés of ruderal communities during two time periods within the Bratislava City (in southwestern Slovakia) were analyzed. The old dataset consisted of 387 relevés recorded in the years 1975–1982, and the more recent dataset consisted of 308 relevés from the years 2011–2014. The relevés from both time periods were assigned to phytosociological classes via the same procedure – numerical classification (hierarchical clustering) using HIERCLUS software. The average values of the percentage number and percentage cover of the archaeophytes and neophytes as groups in the earlier and more recent relevés of each class were compared by the main effects ANOVA analysis in the STATISTICA 7.0 software. The proportion of each taxon of archaeophytes and neophytes in both datasets was also calculated. The invasive status, origin, and life forms of alien species in both datasets were compared. In total, both datasets comprised 120 archaeophytes and 71 neophytes. The old dataset contained more archeaophytes than the more recent dataset. On the contrary, the more recent dataset contained more neophytes than the old dataset. In the years 2011–2014, more invasive neophytes were recorded than in the past. The results revealed a statistically significant decrease in the average percentage number of archaeophytes in the classes Stellarietea mediae, Artemisietea vulgaris, and Galio-Urticetea, and a decrease in the average percentage cover of archaeophytes in the class Artemisietea vulgaris, compared to the past. On the contrary, a statistically significant increase in the average percentage number and cover of neophytes in the classes Artemisietea vulgaris and Galio-Urticetea was recorded. Some rare species of archaeophytes were only recorded 30 years ago (e.g., Kickxia elatine, Silene gallica). Furthermore, several species of neophytes (including some invasive taxa, e.g., Fallopia japonica, Helianthus tuberosus, Juncus tenuis) occur only currently in the ruderal vegetation of Bratislava.
In 2009 and 2010, monitoring of conservation status and future prospects of the forest communities of Quercetea robori-petraeae Br.-Bl. et R.Tx. 1943 class was conducted in the Sudetes and their foothills. 31 sites were selected. At each site, three phytosociological releves were collected. An important component of the global assessment of oak forest communities is the occurrence of synanthropic species as measured by three indicators: occurrence of alien species (kenophytes), occurrence of synanthropic native species (apophytes) and occurrence of geographically alien tree species. At most sites, alien species and native expansive species were not observed or were represented by single specimens. For each site and releve, the index of synanthropization was calculated. The main role in the synanthropization of the investigated acidophilous oak forests is played by apophytes. The values for the synanthropization index suggest that this process is not advanced. However. the impact of synanthropization on species richness and floristic diversity of communities within oak forests is noticeable.
The aim of the study was to determine the degree of the enrichment of the flora of peat bogs and transition mires in anthropophytes and apophytes. The study included the flora of 87 bogs and mires in the Kashubian Lakeland and Kashubian Coastal Region. 149 species of synanthropic plants were found, most of which were found at a single site. Apophytes represented nearly half of the total number of synanthropic species. Archeophytes were the most numerous anthropophytes. Most of the species locations were noted in the most disturbed parts of mires: rural roads, eutrophic lags and sites with allochtonic substrate. A few species such as Quercus rubra, Picea abies and Larix decidua prefer seminatural habitats. CCA analysis revealed that the degree of synanthropization is positively correlated with the area of a mire, the roads crossing the mire, signs of peat exploitation, and the presence of nearby meadows or pastures. It was negatively correlated with the presence of nearby forests.
In 2009 and 2010, floristic research was carried at two sites in Wrocław, Poland. The first site was along 3.5 km stretch of the newly built city ring road between Bielany and Oporów. The second site was along a newly built road near the post office in Oporów. The aim of the study was to determine whether spatial and technical urbanization in the area has favored the development of a variety of segetal and ruderal communities. The sites examined were divided into four parts. Part 1 comprised the 2 to 3 meter wide zone immediately adjacent to the road. Part 2 comprised the 10 to 15 meter wide zone which had been used to load soil when the road was being built. Part 3 comprised wastelands, and Part 4 comprised cultivated fields. 11 species were found in Part 1, 64 in Part 2, 42 in Part 3, and 17 in Part 4. The appearance of different species did not last long because during construction, the soil screes in Part 2 were eliminated and the plants growing there were damaged. For two or three years after road construction was finished, many species were found in Parts 1 and 3, which increased the richness of the flora along the the Wrocław ring road.
One of the many areas where Matteucia struthiopteris (L.) Tod. is found in Poland is the upper part of the Vistula River Valley, mainly in the Silesian Foothills and the Silesian Beskid. From 2005 to 2010, floristic and phytosociological studies were carried out to determine the presence of ostrich fern stands and plant communities that contain this species. As a result of this study, 31 sites on which the species was found were identified. With the help of phytosociological relevés collected using the Braun-Blanquets method, six plant associations were identified that are subject to different levels of anthropopressure. The most commonly observed form the degeneration of plant communities containing the species is neophytisation. In all of the phytocoenoses studied, from two to nine kenophytes were identified. Of these, Impatiens glandulifera, Reynoutria japonica and Robinia pseudoacacia play a significant role in shaping phytocoenoses and pose a threat to the Matteucia struthioptheris population. In order to protect sites on which Matteucia struthiopteris grows, it is necessary to mechanically combat invasive plant species and extend legal protection to the best preserved phytocoenoses which contain the species.
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