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The present study was the determination the correlation between values of two chlorophyll meters: SPAD-502 and N-tester, indulging in comparison scientific results with these two different devices. To this purpose, the six kinds of cereals in stage of heading were examined on “index of greenest”: oat, barley Rataj and Nagrad, triticale, wheat and rye. Statistical analysis carried out afterwards demonstrated that, between measurements received from two chlorophyll meter founded high efficiency of linear regression. To recount values between the chlorophyll meters can be use equation: (N-tester reading) = 14.5·(SPAD reading) – 73.4.
In an agricultural landscape small midfield ponds fulfill biocenotic and physiocenotic functions. A variety of species settle in areas of midfield ponds. The aim of our studies was to determine whether the occurrence of aquatic and marsh species in the studied bodies of water is a random effect or a result of spatial autocorrelation. On the basis of conclusions from ESDA, the hypothesis of spatial randomness can be rejected, which opens the way for searching spatial regimes. The review analysis of the spatial data (ESDA) with the use of join-count statistics showed that there is a positive spatial correlation for the midfield ponds in the agricultural area of the Pyrzyce-Stargard Plain in the distribution of ten aquatic and rush species for a distance of 1,250 m. The results of statistical analysis (ESDA) can constitute the basis for the choice and protection of midfield ponds as stop islands fulfilling functions of "mini" ecological corridors in spreading plant species.
Oznaczono zawartość chlorofilu a + b w liściach żyta ozimego, pszenżyta ozimego, jęczmienia jarego, pszenicy jarej, pszenicy ozimej, jęczmienia ozimego i owsa standardową metodą Arnona oraz za pomocą chlorofilometru SPAD- 502. Pomiary wykazały wysoką korelację między obiema zastosowanymi metodami. Analiza statystyczna udowodniła podobieństwo w przebiegu prostych regresji dla żyta i pszenżyta ozimego oraz dla jęczmienia jarego i pszenicy jarej.
The water quality of small bodies of water is largely differentiated due to the type of use of the catchment area. The water ponds in agricultural regions can be classified according to different characteristics of the neighborhood (villages, afforestation, meadows, fields). In our study, using statistical analysis CA, a hypothesis about the significance of the influence of the type of neighborhood on the chemical composition of the water of the studied bodies of water situated on soils of high productivity was verified. It was observed that differences between types of environment were related to parameters such as: concentration of K, NO₃⁻, Mn, Li, Cd, and pH of water. The smallest concentrations of macro- and microelements were characteristic of the water bodies surrounded by trees. The conducted studies and the results of statistical analysis FA and PCA made it possible to reduce the number of main factors affecting water quality to 60%.
Due to their small size (0.02-1.0 ha), distinct boundaries, and conditions highly contrasting with those in the surrounding area, midfi eld water bodies are regarded as the so-called habitat islands. Their effective conservation calls for knowledge on their inhabitants’ dispersal potential. However, direct empirical data are available for very few species only, but dispersal potential of a species may be inferred indirectly, from its distribution. The study addressed the question whether there is spatial autocorrelation in the distribution of plant species in midfi eld water bodies, or if the distribution is random. Spatial distribution of the midfi eld water bodies surveyed was analysed using the CrimeStat software, while spatial autocorrelation in distribution of 29 species was explored with the joincount.test routine of R CRAN software. Explorative spatial data analysis (ESDA) involving join-count statistics showed the presence of positive spatial autocorrelation in the distribution of ten hydro- and helophytic species. In their case, ESDA made it possible to reject the random distribution hypothesis, which opens up an avenue for exploring spatial patterns. Activities promoting the occurrence of species with limited dispersal potential should take into account their preferences in terms of shorter distances between neighbouring sites. This should make it possible to plan conservation of midfi eld water bodies not only as refuges, but also as stepping stone habitats facilitating migrations of wild species growing in an agricultural landscape.
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