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Introductions of new species by polar expeditions to Antarctica, and to the Arctic, had started by the turn of 19th century, with old polar expedition of Cook, Lisianskij, Bellingshausen, Kotzebue. Place and species were listed.
Rubus occidentalis L., native to eastern North America, is recorded for the first time as naturalized in Poland. Its spontaneous occurrence in Europe has hitherto been mentioned only from several stands in the Czech Republic and from single localities in Slovakia and Russia. The increasing popularity of black raspberry cultivation and its ability to survive under different environmental conditions suggest that the number of instances of its appearances in semi-natural habitats will grow over time. At the moment, R.occidentalis can be considered as a locally established, non-invasive neophyte.
Authors give the first record of introduced dermestid beetle species Reesa vespulae (MILL.) in Poznan in the chambers of University of Life Sciences, and summarize data about its range in the world.
Edible dormice Glis glis Linnaeus, 1766 were monitored from 1996–2008 inclusive. This has been the first population study of this non-native species since its introduction to Britain in 1902. Dormice were present in nest boxes from May or June until October or November. Numbers recorded varied greatly from year to year, and breeding failure occurred in 6 of the 13 years, apparently in response to environmental cues such as food availability. Litter sizes declined with growth of the young but some of the largest litters resulted from females aggregating their offspring. Males used more nest boxes than females, some of whom showed clear site fidelity from year to year. Survival rates were high and some individual lifespans exceeded 9 years. Longevity, compensating for periodic reproductive failure, and an extremely short active season, make the life history of edible dormice exceptional among small rodents, perhaps unique. Population density, rate of population increase and evidence for local emigration in non-breeding years are discussed, issues of particular significance in populations of recently-established introduced species such as this.
For the plant species, effective phenology and pollination syndromes can increase viable seeds which enhance the species to colonize new areas. So the species with a suit of advantageous characteristics inherent in its reproductive ecology is critical to its dispersion. Spartina alterniflora – a perennial grass native to coastal marshes of America was introduced to China in 1979 and now it is distributed in the Tianjin coastal wetlands of northern China. Flowering phenology was examined and indicated that in northern localities, flowering initiated in mid-August and senescence occurred by the end of October. The pollen-ovule ratio was 9875 (±2150). Abundant pollen grains compensated for a lack of pollen viability. Pollen viability was 10% approximately when pollen released 4 hours, but stigma receptivity was above 10% when stigmas exserted 7 hours. Stigmas maintained viability longer than the period of pollen release, ensuring successful pollination. Scanning electron microscopy was used to observe stigma surface characters and pollen viability. Further investigation proved stigma adaptations to increase pollen capture and exterior pollen tube growth following pollination was beneficial to fertilization. The results suggested that flowering phenology and pollination traits are vital to pollination and production of viable seed, enabling the species to spread rapidly and succeed in new habitats of northern China.
Lobiopa insularis (CASTELNAU, 1840) was found on Canary Islands. It originates from the New World. The species is new to the Palaearctic fauna.
Dendroclimatological research based on the response function and the Huber's method concerned 5 populations oř Douglas fir (Pseudotsuga menziesii Franco) from the territories of Western Pomerania, Great Poland and the Beskid Żywiecki. The aim of the research was to determine the influence of the climate on the formation of cambial growth of the species that had been introduced into die Polish forests. It was concluded that thermic conditions of winter time had a very big impact on the annual growth of Douglas fir which grows on the lowlands, and a smaller impact on that from the mountains. Pluvial conditions played a less important role in the tree-ring formation process.
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