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The paper reports the share of anthropophytes in small forest complexes i.e. in forest patches along watercourses, tree lines along roadsides, and clumps of trees surrounded by fields in the Żuławy Wiślane. The largest share in the flora of the sites examined represents native species. Alien synanthropic species comprise about 17% of the total flora. Kenophytes represent 48% of the alien species, and archeophytes represent 30%. Synanthropic species were especially numerous in clumps of trees surrounded by fields, where 54 species were found. 42 species of anthropophytes were found in tree lines along roadsides, and 35 species were found in forest patches along watercourses. Among the anthropophytes found were: Lamium album, Padus serotina, Prunus cerasifera and Solidago gigantea. Tree lines along roadsides had the highest values for the anthropophytization index. Forest patches along watercourses had the lowest degree of synanthropization, with the lowest values for the anthropophytization index, the kenophytization index and the fluctuations index.
The paper presents spatial variation in floristic indices in the mediumsize valley of the San River. Indices of species richness and synanthropization rates were calculated for 366 1 x 1 km cartogram squares. The Spearman rank correlation coefficient was used to analyze the relationships between individual indices. Species richness in individual basic plots ranges from 102 to 391, with a mean of 248. The share of anthropophytes ranges from 0.9% to 35.5% , with a mean of 18.1%. In general, the flora of the present valley floor is characterized by a higher species richness and a higher anthropophytization rate than glacial terrace. There was a positive correlation between species richness and the number of anthropophytes present, but no correlation between species richness and the anthropophytization rate. In individual basic plots, their values can be very divergent.
Presented in the paper are characteristics of the meadow communities and assessment of the degree of their synanthropization. The studies were conducted on meadows utilized in Walim District at the base of the Sowie Mountains in 2009 and 2010. Floristic releves were collected using the Braun-Blanquet method. The material obtained served to define the phytosociological affiliation and to estimate the degree of synanthropization on the basis of the following indexes: synanthropization, apophytization and anthropophytization. The meadow communities studied were representative of the class Molinio-Arrhenatheretea. Within this class, four phytosociological units were allocated: Arrhenatheretum elatioris, the community Poa pratensis-Festuca rubra as well as two communities with either Agrostis capillaris or Alopecurus pratensis. The meadows examined were characterized by a high average level of synanthropization. The highest values for the synanthropization and apophytization indices were found in meadows of Arrhenatheretalia, in Poa pratensis-Festuca rubra and of Agrostis capillaris. The lowest values were found in the meadow the class Molinietalia. The high values for the apophytization index show that most of the species found in the meadows are of native origin. The low values for the anthropophytization index confirm that only an small number of geographically foreign species are found in extensively utilized meadow communities.
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.
W dolinie Środkowej Mogilnicy oceniano walory przyrodnicze zbiorowisk łąkowych na podstawie liczby gatunków, wskaźnika różnorodności florystycznej Shannona-Wienera (H’) i metody waloryzacji Oświta oraz ich wartość gospodarczą i użytkową (LWU). Określono ponadto warunki siedliskowe wyróżnionych zbiorowisk: uwilgotnienie (F), odczyn gleby (R) oraz jej zasobność w azot (N), z zastosowaniem liczb wskaźnikowych Ellenberga. Walory przyrodnicze i użytkowe wyróżnionych zbiorowisk zależą od usytuowania w dolinie. Zbiorowiska położone najbliżej rzeki, zaklasyfikowane do klasy Phragmitetea, wykształcone są w formie typowej i przedstawiają duże oraz umiarkowanie duże walory przyrodnicze (od V do VII klasy waloryzacji), jednakże ich ruń ma najczęściej niską wartość użytkową (LWU od 1,63 do 6,90). Aktualnie użytkowane zbiorowiska klasy Molinio-Arrhenatheretea przedstawiają umiarkowane walory przyrodnicze (III i IV klasa waloryzacji). Z łąk tych uzyskuje się wysokie plony I pokosu (4,4 do 5,7 t s.m.· ha-1) o dobrej wartości użytkowej (LWU od 7,37 do 7,56).
Anthropopressure directly and indirectly affects changes in species composition in plant communities, including communities of Phalaridetum arundinaceae. Variations in habitat conditions, especially moisture content, contribute to the disappearance of typical rush associations and lead to the development of lower phytosociological units. The natural value of Phalaridetum arundinaceae syntaxons is affected by the relative share of synanthropic species. Their occurrence is determined by habitat conditions and land use.
This study is part of a long term, multi-faceted research project on rates and directions of spontaneous vegetation dynamics after cessation of agricultural land use, and on the effects of anthropogenic modifications of this process by managed mowing or plowing. The results are based on data from a permanent plot established in Wielkopolski National Park in 1976. This article presents share spectra for certain groups of anthropophytes with after various experimental treatments from a spatial and temporal perspective. An attempt is also made to connect these spectra with successional and fluctuational changes.
The paper presents phytosociological records of the mire nature reserve Torfowisko Kunickie near Legnica, SW Poland, which are compared with previous data. The clear effects of eutrophication of the mire surroundings connected with an increasing drying out (because of existed drainage ditch system and low rainfalls during last years) cause that associations of oligo-/dys- and mesotrophic habitats are superseded by communities which are characteristic for higher level of biogenic elements within substratum. The dominant plant community in the nature reserve is Carici elongatae-Alnetum. The most numerous associations (12) represent the class Phragmitetea australis. 7 valuable plant communities are not confirmed (e.g. Scorpidio- Utricularietum minoris, Caricetum appropinquatae, C. limosae, C. lasiocarpae, C. diandrae). However, 13 others are new for the reserve (e.g. Acoretum calami, Impatientetum parviflorae, community with Urtica dioica, community with Glechoma hederacea, cfr. Urtico-Calystegietum, Ceratophylletum demersi).
Among many threats to global biodiversity, invasion by alien species are perceived as very important. Activities aimed at counteracting this process should be preceded by updating the list of alien species and choosing appropriate terminology and classifications. In the paper, terminology still used by Polish authors is compared with that used in current English-language publications. Some examples are given to support the thesis that particular alien species should be periodically reviewed with respect to distinguished groups of synanthropic plants. The need for review can be supported by many examples of species classified only two decades ago as ephemeral and currently belonging to established elements of the local floras of some regions. Introduction of the EU Strategy on Invasive Alien Species will require compiling different lists of alien plants according to their impact on the environment, the economy or health. Papers published recently in Poland will help elaborate so-called white, black and gray lists of alien plants, but some activities aimed at implementing monitoring of invasive species should be undertaken, as should the elaboration of legal solutions.
The conservation status of the communities of the class Asplenietea trichomanis was studied in 2010 in southern Poland. In all, 81 sites with rocky plant communities were selected, and 270 phytosociological relevés were collected. Alien species were found at 27% of the sites. This indicates that the rocky communities there are exposed to strong pressure of plant invasion. The most common alien species was the neophyte Impatiens parviflora, which occurred at 25% of the sites and 12% of the relevés examined. Robinia pseudoacacia was also locally invasive, especially on partially shaded serpentine rock. The other alien plant species were found only locally and in small numbers, and are not invasive at this time.
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