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Segetal flora of the Middle Vistula River Valley

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The objective of the study was to describe the segetal flora of the Middle Vistula River Valley. A total of 367 species were recorded in spring and winter cereals, tuber crops, and stubble fields. Such floristic abundance may be due to the fact that the study area is located in the proximity of a river where semi-natural communities interact directly with communities inhabiting cultivated fields and that fields are fragmented and characterised by different habitats. There were more apophytes (62%) than anthropophytes (38%) in the flora studied. Meadow apophytes were the dominant native species (35%) and archeophytes were the dominant anthropophytes (69%). The analysis of the life spectrum revealed that there were more therophytes (50%) than hemicryptophytes (39%). What is more, non-perennial species constituted 56% and perennials 44% of the segetal flora established in the Middle Vistula River Valley. The large proportion of archeophytes (26%) may indicate that traditional farming predominated in the study area.
Badania składu i struktury agrofitocenoz ziemniaka przeprowadzono w latach 2003-2006 na obszarze Doliny Środkowej Wisły metodą fitosocjologiczną Braun- Blanqueta. Obserwacje wykonano na 143 plantacjach rozmieszczonych w różnych warunkach siedliskowych. Warunki siedliskowe określono wykorzystując mapy glebowo-rolnicze w skali 1 : 5 000 oraz oznaczono pH gleby metodą kolorymetryczną. Ekologiczne wskaźniki dominacji i bioróżnorodności policzono według wzoru Shannona (H’) i Simpsona (SI). Celem przeprowadzonych badań było określenie gatunków dominujących na różnych siedliskach oraz przedstawienie różnorodności florystycznej zbiorowisk zachwaszczających plantacje ziemniaka w oparciu o wskaźniki ekologiczne. W uprawach ziemniaka odnotowano ogółem 202 gatunki chwastów, w tym 126 krótkotrwałych i 76 wieloletnich. Najuboższą florą charakteryzowały się uprawy na glebach kompleksu żytniego bardzo słabego i słabego. Obliczone wskaźniki dominacji gatunków w tych fitocenozach były wysokie, co wynikało z małej bioróżnorodności zbiorowisk oraz udziału gatunków w wysokim stopniu zachwaszczenia. Natomiast najbogatsze fitocenozy wystąpiły na siedliskach żyznych i charakteryzowały się wysokim indeksem bioróżnorodności oraz wysoką średnią liczbą gatunków chwastów.
The work presents the results of a study on the biodiversity of agrocenoses using ecological indices. In order to calculate the measures, phytosociological relevés were made and exact methods were applied in winter cereals, spring cereals, tuber crops and stubble fields. The objective of the work was to compare ecological indices (Simpson’s index of dominance C, Simpson’s index of species richness D, and Shannon-Wiener index of biodiversity H’) calculated using the number of plants and their cover determined based on the degree of presence. Moreover, correlation analysis was conducted between the indices computed using the two approaches applied. The results of the study revealed significant differences between all the indices calculated using the exact and approximate methods. In turn, comparisons of the measures computed for individual crops showed significant differences only for potato crops and winter cereals. No significant differences were found between the indicators calculated for spring cereals and stubble fields.
Growing winter wheat in five-year monoculture caused a very high reduction in yield and increased weed infestation. The both facts were closely correlated. A light response of wheat to chemical weed control was observed. A remarkable yield-increasing effect was obtained using standard doses of herbicide Glean 75 DF. The weed growth was most effectively limited by the application of double and triple doses of Glean. Weed infestation level was considered to be one of the most important yield-decreasing factors in wheat monoculture till the fourth year of cultivation. A rapid yield decrease in the next years of winter wheat cultivation, regarding to all variants of chemical weed control, was observed. The increase of weed control intensity did not prevent negative effects of wheat monoculture.
The characteristics of communities found in unploughed stubble fields of the Mazowiecki Landscape Park and its agricultural buffer zone are presented in the paper. The association Echinochloo-Setarietum divided into a typical variant, the variant with Galinsoga parviflora, and the variant with Bidens tripartite, was the most frequently noted and floristically differentiated association. Patches of Digitarietum ischaemi were also frequently observed in stubble fields on the poorest habitats. Rarely, on fertile soils, small patches of floristically rich communities with Veronica agrestis were recorded. Periodically, excessively wet habitats were seldom occupied by the speciesrichest phytocoenoses of Centunculo-Anthoceretum punctati. Single patches of the community with Setaria pumila, the form with Aphanes arvensis, were observed only in the south-eastern part of the Park.
This paper presents a description of segetal communities in potato crops cultivated in the Masovian Landscape Park. The communities were analysed based on 64 phytosociological relevés made at 45 localities. 4 associations were found in the study area, that is, Digitarietum ischaemi, Echinochloo-Setarietum, Galinsogo-Setarietum, and Lamio-Veronicetum politae. Phytocenoses representing the associations Digitarietum ischaemi and Echinochloo-Setarietum were most varied floristically. Lower syntaxonomical units were determined within these associations, that is, subassociations and variants. These phytocenoses were frequently found; they occurred in various habitats characterized by different trophic and moisture conditions. Patches of the association Lamio-Veronicetum polita were rare and they occurred only on fertile soils and on small areas.
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