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Study of meadow grass biology were started already in the thirties. After the second world war number and range such kind of studies had increased systematically and their methodology had been improved. The studies were carried out in the control conditions and as field experiments, in pure stands and in mixtures, in specialist as well as in practical experiments. The results obtained have allowed to explain many occurrences which took place in the applied studies and they affected improvement of rational management of grassland and helped in valorisation and characterisation many of grass species. Continuation of grass biology studies is necessary but in complex way and in co-operation with different branches of basic sciences using modern equipment and unify methods of studies.
The aim of the analysis conducted on the street lawns in Warsaw was to specify the share of grasses in the sward. Floristic research was conducted by means of phytosociological record method according to the Braun-Blanquet's school and it analysed plant cover. Furthermore, the research compares grasses share in sward depended on soil salinity. According to research from 1999-2001 the street lawns comprised of 80 species, out of which 16 were grass species. External belts of street lawn sward comprised of 55 plant species, with 12 grass taxa. Internal belts of street lawns comprised of 61 plant species, out of which 14 were grass species. The percentage of plants in middle belts of the street lawns reached 96% of plant cover and in side belts - about 70% of the plant cover. External belts of street lawns comprised from 24 to 33 dicotyledonous plants and 3 to 9 grass species. Grass species constituted 21.0-38.6% of street lawn's plant cover. The electrolitic conductivity reached from 0.8 to 1.2 mS cm⁻¹. Research compared individual species' share in lawn sward and it showed that, among grass species, Agropyron repens, Setaria pumila, Puccinellia distans, Festuca rubra and Bromus hordeaceus have the highest indices of plant cover. Internal belts of street lawns comprised from 20 to 29 dicotyledonous plants and 6 to 10 grass species. Grass species constituted 26.8-40.4% of street lawns' plant cover. The electrolitic conductivity reached from 0.3 to 0.45 mS cm⁻¹. Research compared individual species' share in lawn sward and it showed that, among grass species, Festuca rubra, Lolium perenne, Agropyron repen, Bromus hordeaceus and Dactylis glomerata have the highest indices of plant cover.
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Trawy na grodziskach Wielkopolskich

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In the earthworks of the Wielkopolska region a wide spread of grasses and their significant role in creating of the whole communities can be observed. These historical objects being the remnants of primaeval and medieval settlements are frequent elements of the landscape in Wielkopolska. In the earthworks of Wielkopolska, Poaceate are the second family after Asteraceae as regards their number of species. They comprise 80 species and together with Asteraceae (89 species) they consist over 20% of the fora of earthworks. As regards a number of records indicating frequency of the occurrence of species from a given family, grasses with the result over 3400 records get ahead Asteracae and are without dispute a leader among other families. Most often grasses are found in grasslands, which were formed on embankments and cones of earthworks also in forests and different types of thickets. Grasses were observed most often on early- and late-medieval objects regarding chronology of rescarch sites. Refferring to hemeroby of habitat grasses grow in greater numher in mesohemerobic biotops. In relation to the resources the plants studied occur on the second level which means they covered to 50% of record area. Calamagrostis epigejos, Elymus repens. Poa protensis and Bromus inermis were generally noted whit the biggest resources ("3"). In comparison to the whole flora of the earthworks, among grasses there are more species in higher frequency classes i.e. frequent, very frequent and common ones. The share of moderately frequent species is nearly the same both compared groups. In the Poaceae family similarly as in the whole flora of earthworks dominate native species. Their share is nearly identical in the earthworks 77.4%, among grasses 76.3%. The significant differentiation in the composition of geographical-historical groups can be stated in respective groups of alien species. Among the grasses there are more archaeophytes (2.41% more) and ergasiophytes (1.3 % more) than kenophytes (2.4 %) less). Analysing spectrum of life-forms (Raunkiaer's gropus) in the grass family there were found only three main groups: hemicryptophytes, cryptophytes (geo- and hydrophytes) and therophytes. Dominate hemicryptophytes with 64% share. The number of species in sociological-ecological groups ranges form 2 to 22. In the flora of grasses the most numerous are the plants from the meadow, pasture and grassland communities (groups 3 and 4), together 33 species (over 40%). A very numerous group also are species from mesophilous forest communities and nitrophilous thickets (group 8) and from segetal (group 9) and ruderal (group 10) communities. Altogether, these three groups constitute ovcr 30% of the whole flora of grasses. Within the grasses growing in the earthworks legally protected species were not recorded and share of threatened taxa was rather little, only 2.5%. The species threatened in Wielkopolska and found or objects studied are only Bromus ramosus (category E – endangered), and Trisetum flavescens (V - vulnerable).
Reclamation of the derelict land is very actually problem in reconstructed region - agglomeration of Katowice. This places are colonised, in a spontaneous succession process of the vegetation by some plant species. Investigation of this process are continued in spoil heaps in Upper Silesia region (CABAŁA AND SYPIEŃ, 1987; PATRZAŁEK AND ROSTAŃSKI, 1992; ROSTAŃSKI, 1997a; ROSTAŃSKI 1997b), in other post-industrial sites of Poland (BALCERKIEWICZ AND PAWLAK, 1990) or Europe (JOCHIMSEN ET AL., 1995). The aim of this paper is to present up-to-date floristic list of grasses, which spontaneously exist in post-industrial sites in Upper Silesian region and the short analysis of this list. The flora of grasses consists of 57 spontaneously occurring species. Native species contributed 70% of the total species number. Among alien species (30%) the important groups are archaeophytes (15%) and kenophytes (10%). In total flora the perennial (hemicryptophytes, geophytes), heliophilous, mesophilous and expansive grass species are dominated.
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Dynamika wzrostu wybranych traw w rejonie gorskim

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The investigations were conducted in 1994-1995 in the mountain area situated 650 m a.s.l. Dynamic of growth and development of two grasses Arrhenatherum elatius and Dactylis glomerata was compared with the indigenous wild growing Holcus mollis. Every year the experiments lasted for 8 weeks, which included the period of growth from the beginning of grass vegetation till their cutting maturity. The date of the vegetation start was determined in the studies and the height of plants was assessed every two weeks, and dry mass yields and daily increase of those yields were determined. Arrhenatherum elatius was the species, which started its vegetation at the earliest date and was characterised with the greatest growth dynamic while Holcus mollis was placed the last. The biggest growths of dry mass were detected at the shooting stage. It was on an average twice bigger than in the tillering and earing stages and even between 3 and 5 times bigger than in the period after earing. At the shooting stage daily increase in Arrhenatherum elatius yields were on an average twice bigger than for Dactylis glomerata and Holcus mollis.
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Nasiennictwo traw dla rekultywacji terenow trudnych.

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On the basis of turf cultivars testing in few regions of Poland during 1991-98 and literature studies, the ranking of specics tolerant to common stress conditions was presented. As an example of Poa pratensis cultivars it has been demonstrated relationship of turf quality (OA) under different type of maintenance: extensive (Park and Eko), medium intensive (Relax) and extensive (Sport) and seed yielding character. In other test it has been shown efficiency of resistance to stresses of Festuca rubra, endophyte-containing cultivar. The group of species were proposed to following stresses: drought, high moisture, wearing, low cutting, shade, toxicity of soil and severe winter. It was shown seed production of grass species in Poland and European Union with taking into consideration the species of minor agriculture meaning. Cultivars tests showed high correlation the turf quality between Relax, Park and Eko maintenance (r = 0.73, r = 0.90) and low correlation coefficients between Sport maintenance (r = -0.19, r = 0.22). The cultivars differed significantly in height of plants (max. to 260%) and seed yielding (max. to 270%). It was confirmed that seed infection by Acremonium can improve some stress resistance of cultivar, but these effect in average value OA was not so big.
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Perspektywy hodowli Lolium perenne

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Lolium perenne is a species characterized by wide adaptive variability. This feature is responsible for creative breeding of fodder and turf varieties. This species has been bred for more than 100 years. During this time dozens of fodder varieties were produced with the use of classic breeding methods. The varieties were characterized by high feeding qualities. Besides, many turf varieties were with excellent utility and visual qualities were produced. New trends in biotechnology, especially in molecular diagnosis and genetic engineering, create many opportunities for widening the genetic variability for the breeding of new, improved and specialized varieties.
Na podstawie literatury i prac własnych scharakteryzowano przydatność wybranych gatunków i odmian traw jako komponentów do mieszanek na pastwiska trwale i przemienne. Wyróżniono pod względem wczesności trzy grupy gatunków i odmian: wczesne, średniowczesne i późne. Opracowano skład 15 mieszanek: 9 na pastwiska trwałe i 6 na przemienne.
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