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Field experiments were conducted to evaluate the efficacy of glyphosate (H1) and fluazifop-P-butyl (H2) herbicides with adjuvants on the common reed without cutting and at two different cutting levels (10 and 30 cm). The adjuvants were urea, nitric acid and sulfonic acid. The relative importance value (RIV), leaf chlorophyll content and plant density were determined to assay the efficacy of herbicides. Glyphosate treatment only (H1 a) was more effective than fluazifop-P-butyl (H2 a) on reeds without cutting and at the 10 cm cutting level. However, no significant difference was observed between them at the 30 cm cutting level. A positive effect of plant cutting occurred on the efficacy of all herbicides applied alone or in a tank mix with adjuvants. Furthermore, the 10 cm cutting level was more effective in eradication of reeds than the 30 cm cutting level. The adjuvants significantly improved the efficacy of the recommended (Hb) and half recommended (Hc) herbicide rates in comparison to being used alone on uncut reeds. The reduction percentages were 94.5, 86.99, 76.61 and 69.94 for H1 b, H1 c, H2 b and H2 c treatments, respectively. However, the adjuvants did not improve the glyphosate effect at different levels of cutting. Conversely the reduction percentage of reeds was improved by the recommended rate of fluazifop-P-butyl with adjuvants (H2 b) to 92.77% and 84.62% at 10 and 30 cm cutting levels, respectively.
Differences between 13 common reed (Phragmites australis) populations, growing in urban conditions within the town of Poznań (western Poland), are described by 8 morphological traits of panicles' variability and the frequency of peroxidase (dimeric and monomeric) allozymes. Values of morphological characters were processed statistically using agglomerative clustering by the closest neighbours (UPGMA) method based on Euclidean distances. Proteins were separated in the starch gel electrophoretic procedure, showing cathodic migration. Populations are polymorphic and have a certain level of heterozygosity. The level of populations' diversity (DST = 0.097) is lower than the intra-population variability (GST = 0.187). The gene flow between populations is rather low (Nm = 1.090).
Results of the survey into expansive growth of the common reed (Phragmites australis (Cav.) Trin. ex Steud.) carried out in the upper Narew River valley (NE Poland) within the whole area of Narew National Park (6810 ha) (NNP) are presented in the paper. The Narew River is an anastomosing river in the part subjected to the analysis and an open swampy bog ecosystem has formed within its valley. Sedge communities and to a lesser degree meadow communities are typical plant communities in the study area. Till the end of the 1970’s, the area was agriculturally used. Since the beginning of the 1980’s when grassland mowing was discontinued, expansion of reed communities has been recorded. The analysis of reed expansion has been based upon data on its range originating from interpretation of aerial NIR photos made in 1987 and 1997. The field survey and analysis of the air photos have shown that the reed expansion rate differs depending on the location in the study area. Assessment showed that in 1987 the total area of the common reed stands equalled 1214.75 ha (18% of the NNP area), and in 1997 – 2300.6 ha (34%). Due to considerable homogeneity of habitat features within the valley and habitat requirements of reed, a basic hypothesis has been put forward that the rate of reed expansion in terms of the increase of reed community area is related to bankline density and length. The material obtained and statistical analysis have confirmed that assumption. Besides, it was mentioned that cessation of mowing sedge grasslands along with a change in character of spring surface flooding also contributed to reed expansion.
Some physiological properties and a number of heterotrophic bacteria inhabiting the surface of the root system of the common reed (Phragmites australis [Cav.] Trin. ex Steudel) were studied in two different types of bottom sediments (sandy and silty), and the bacteria were identified. For comparative purposes, samples of the bottom sediments from the sites where the reed grew were subjected to microbiological tests. It was found that the number of bacteria growing on the root system of the common reed and those inhabiting the types of bottom sediments tested increased from spring to summer and then decreased in autumn. On the surface of the rhizomes of the reed growing in silty sediments, a higher number of bacteria was always noted than on the surface of rhizomes growing in sandy sediments. Also, the number of heterotrophic bacteria in samples of bottom sediments was always higher in silty sediments than in sandy sediments. Lipo-, proteo- and amylolytic bacteria and bacteria capable of producing ammonia from organic compounds were dominant among all the isolated strains. The lowest numbers were found of chitinolytic bacteria and those that form hydrogen sulphide from organic compounds. Strains isolated in spring - both from the root system of the plant and from the samples of sediments - were potentially the most active physiologically. As a result of the identification of the isolated bacterial strains, it was found that bacteria from the Arthrobacter-Corynebacterium group and the Achromobacter genus are dominant in the root system of the common reed and in sandy and silty sediments.
This paper reports results of speciation analysis of selected heavy metals (Fe, Mn, Zn, Ni, Cu, Pb, Cd) in bottom sediment samples collected from 11 lakes in the area of Wielkopolski National Park, which is a protected area subjected to limited anthropogenic factors, The main aim of the study was determination of the distribution of the metals among five speciaiton forms defined by Tessier: exchangeable, bound to carbonates, bound to hydrated oxides of iron and manganese, bound to organic matter and others. The particular forms were isolated by sequential extraction..
We collected and examined water plant samples of floating pondweed (Potamogeton natans) and Common reed (Phragmites australis). The samples were taken from places situated along the Drawa River (before, next to and below the military training ground). Cu, Ni, Cd, Pb and Zn content was indicated in plants. The received results showed the essential difference of the heavy metals content between plants from various places. The military training ground is a source of Drawa River contamination by heavy metals.
The population structure of Phragmites australis (Cav.) Trin. ex Steud. was examined in seven categories of overgrowing flood control ditches, differing on time which had elapsed from the last clean-up. Density, biomass, frequency of development stages, as well as the size and habit of the shoots, were determined in the populations. Site conditions in the ditches and the proportion of the common reed in the total biomass of plants were also examined. The rate at which populations in cleaned ditches regenerate is very quick. Three years after the maintenance works in ditches the reed population is already fully regenerated. Well developed reed rushes, which biomass is about 650 g d.w.m⁻², are dominant. Its density amounts to 76 ± 25 shoots m⁻². Flowering and fruiting shoots are the most numerous. The first signs of population regression were observed in the ditches left without cleaning for more than 5 years. Population density is gradually lower, the proportion of generative shoots is reduced, and the reed is lighter and has smaller assimilation area. In the 11-year-old and older ditches the reed is replaced by other plant species, mainly grasses and shrubs.
In natural environment plants are exposed to many different stress factors, including heavy metals, whose elevated concentration causes oxidative stress, connected with formation of reactive oxygen species (ROS). Therefore, plants have developed defence systems, including enzymatic antioxidant system, able to remove ROS. The work concerns the accumulation of two heavy metals, cadmium (Cd) and lead (Pb), as well as the phenomenon of oxidative stress caused by increased concentration of these metals in common reed (Phragmites australis), a dominant species in the littoral zone of many water reservoirs. The plants were obtained from four water bodies situated in Poznan: Kierskie Lake, Rusałka Lake, Strzeszyńskie Lake and Sołacki Pond. The aim of the study was to examined the accumulation of heavy metals and the relation between activity of antioxidant enzymes in rhizome, stem and reed leaves during the vegetative period. Three antioxidant enzymes were analyzed: ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and superoxide dismutase (SOD). The statistical analysis was done to determine the influence of the heavy metals on the activity of the antioxidant enzymes, involved in limiting and removing results of oxidative stress. Heavy metals were accumulated in common reed in all the four water reservoirs, but the activity of enzymes was variable during the observation period. Statistical analyses suggest that there are some correlations among concentration of metals and the activity of antioxidative enzymes. However, the results do not provide an unambiguous determination of the effect of heavy metals on enzymatic activity. Summing up, the contamination of the water ecosystems caused by heavy metals was so low that it did not influence the activity of the analysed enzymes.
The studies were carried out on common reed (Phragmites australis) growing on the shores of Lake Glinno and forming rush communities of the alliance Phragmition. 10 plants with disease symptoms were gathered from each of five sites. The isolation and marking of pathogens were performed twice from fragments of leaf and blade tissues with disease symptoms. First, directly after collecting the plants incubated in sterile humid chambers and microorganism cultures on CDA and PDA medium, and then phytopathogen and saprotroph species occurring on dried green material were identified for 2-A months. The occurrence of 31 species of microscopic fungi overall was observed on the leaves, blades and inflorescences of P. australis, including 2 mycelia of Mycelia sterilia. The most frequently occurring species, present at all sites of Phragmites australis are: Alternaria alternata, Cladosporium cladosporioides, C. herbarum, Doratomyces stemonitis and Puccinia phragmitis, P. magnussiana and two mycelia of Mycelia sterilia. The most common species occurring on blades and inside them are: Acremoniella atra, Acremonium alternatum and Fusarium sambucinum. Sporadically, Ustilago grandis was also observed inside blades. Tiny necrotic stains on leaves and blades were caused by the presence of three species of the genus Leptoshaeria: L. culmifraga, L. eustoma and L. fuckelli. The occurrence of the sclerote of Claviceps microcephala was found in inflorescences.
Badania nad wpływem wybranych parametrów jakości środowiska wodnego (odczynu, ilość tlenu i jonów chlorkowych) na perifiton zasiedlający trzcinę prowadzono w czterech sezonach 2007 roku w kanałach melioracyjnych Lasku Południowego w Słupsku zarówno stale obfitych w wodę, jak i wysychających. W czasie badań wody w kanałach melioracyjnych charakteryzowały się znaczną zmiennością warunków tlenowych, natomiast porównywalnym odczynem i zasoleniem. Obserwowano natomiast znaczne różnice analizowanych parametrów w poszczególnych punktach. Gorsze warunki tlenowe, a częściowo również większe zasolenie i pH (st. 5) panowały w wysychających kanałach, niż w stale napełnionym wodą kanale głównym. Obserwowano równocześnie mniejsze natlenienie, zasolenie i pH na stanowisku zlokalizowanym przed kolektorem ściekowym niż za nim. W czasie analiz stwierdzono występowanie bogatego jakościowo zespołu organizmów poroślowych, składającego się z 19 taksonów (3 roślin i 16 zwierząt). Glony perifitonowe zdominowane zostały przez okrzemki (87%), którym towarzyszyły sinice (12%) oraz zielenice (< 1%), natomiast wśród mikrofauny poroślowej przeważały Peritricha (47,5%) a w makrofaunie Asellus aquaticus (22,4%). W celu uchwycenia wpływu wybranych parametrów fizyczno-chemicznych wód na skład jakościowy i ilościowy organizmów poroślowych zastosowano metody korelacji nieparametrycznej oraz ordynacyjne (PCA, CCA, DCA, RDA). Projekcja taksonów wskazała, że sedymentatory (Rotatoria) rozwijają się intensywniej w warunkach lepszego natlenienia i przy wyższym pH. Na stanowiskach oddalonych od zrzutu wód deszczowych obserwowano większe zagęszczeniem Testacea, Nauplius i Harpacticoida. Wyższa temperatura sprzyja wzrostowi zagęszczenia Testacea, Cyanophyta i Ciliata libera.
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