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Earthworms are creatures living in different kind of soils. Scientific interest in earthworms is on the rise. In the world the subject of the earthworm is not only a theoretical one. Several big companies in the United States, Canada and Europe have seriously begun sampling institutional and municipal organics as feedstocks for earthworms. Small scale vermiculture - "worm bins" has entered the American schools. The school children actively participate in constructing the bins, preparing the bedding, and introducing the residues to the worm bins. They become to know earthworms better. In Polish schools children need ecological education too. The fantastic idea of worm bins, useful for solving some ecological problems, should be introduced into the school program on different levels of education. Possibilities of the use of earthworms as an object for ecological education are numerous. Experiments on "seeding" earthworms -in the fields if necessary to replace a significant portion of the fertilizer applied, or to reduce compaction and perhaps the number of cultivations necessary, seem to be economically and ecologically justifiable too.
Earthworms, as ecosystem engineers, strongly regulate microbial activities and microorganism-mediated processes in the soil; their effects differ among species and ecological groups. Lumbricids are suggested to have density-dependent regulation of species populations, but it is not known whether their effects on soil processes are density-dependent. In a field experiment, litter/soil microcosms contained monocultures of five common lumbricid species belonging to epigeic, anecic and endogeic ecological groups, at various density levels. After 6 and 15 weeks, respiration rates of soil systems were measured and (after subtraction of approximately calculated earthworm respiration) microbial respiration rates estimated. In the presence of earthworms, respiration of soil systems tended to increase. After 6 weeks, this increment was explained by earthworm's own respiration. However, after 15 weeks earthworm respiration comprised 12–80% of the respiration increment; hence, microbial respiration was stimulated by earthworm activities. In any earthworm species, total community and microbial respiration were correlated with its density increase. However, specific respiration increments (per unit earthworm biomass) were not significantly affected by lumbricid density. The lack of density-dependent patterns indicates a weak impact of lumbricid intraspecific interactions on soil respiration. However, specific respiration increments and stimulation of microbial respiration varied across earthworm species, being higher for endogeic than for epigeic/anecic species. This is explained by a relatively lower microbial grazing by endogeics and a depletion of litter (a resource and environment for the microbial community) by epigeic/anecic earthworms. Overall, the results support the view that microbial community adapts to the presence of earthworms by switching to a smaller, but a more active one.
The earthworms occurrence in pine forests was analyzed. The communities of earthworms in studied areas are characterized by poor species composition and low density. D. octaedra was the dominant.
Odpady organiczne (osady ściekowe z oczyszczalni ścieków komunalnych, odpady z Zakładów Mięsnych, wykorzystane podłoże do produkcji pieczarek, trociny) wykorzystano jako podłoże do hodowli dżdżownic i produkcji biohumusu, cennego nawozu organiczno-mineralnego. W uzyskanych ośmiu biohumusach średnia zawartość węgla ogółem wynosiła (w mg/g): 134.9 a azotu 11.75. Biohumusy ekstrahowano 0.1M NaOH, uzyskując dwa wyciągi alkaliczne. W I wyciągu alkalicznym stwierdzono w stosunku do zawartości ogółem 54.8% węgla i 10.1% azotu a w II odpowiednio 20.2% i 4.9%. Stosunek Ch:Cf w I wyciągu wynosił 3.52 a w II wyciągu 1.36.
W pracy przedstawiono wyniki badań drugiego roku prowadzenia doświadczeń wazonowych dotyczących określenia przydatności nawozowej niektórych materiałów organicznych kompostowanych przez dżdżownice kalifornijskie. Stwierdzono, że rozkład obornika i osadu ściekowego nie wpłynął w istotny sposób na wielkość plonów kukurydzy. Wyższą masę plonów roślin uzyskano jedynie tam, gdzie stosowano obornik zwykły, najniższą natomiast na węglu brunatnym. Zawartość składników pokarmowych i wielkość ich pobrania przez kukurydzę uzależniona była od dawki i formy nawozu wprowadzonego do gleby. Najbardziej widoczne różnice w zawartości i pobraniu wystąpiły dla azotu i fosforu, którego najwięcej stwierdzono w roślinach nawożonych obornikiem. Pobranie wapnia i magnezu nie było zróżnicowane między obiektami.
Analysing possibilities of indicating threats of earthworms for protection demands, it was shown that at the current stage of faunistical work it is not possible to choose the most threatened species in the Polish fauna, which could qualify to one of the threat of the European categories. In the case of this group of animals it is not possible basing, on current knowledge, to determine the category of threat. Although, it is assumed that there are four endemic species (e.g. connected with Carpathian Mts) in this group. The criteria stated in the Polish Red Data Book do not apply to oligochaete. Nearly none of the species can be characterized with demanded precision for chosen criteria, because the lack of quantity and quality data. It is only possible to distinguish „groups of non-determined species”, which are treated as „rare species”, but the lack of enough data does not allow to determine to which group they really belong. The determining of factors affecting the habitation of particular species belongs to a group of the least known subjects. A group of factor affecting one particular earthworm species was not considered yet.
In the present work a comparison was made of microflora abundance and activity of two enzymes in earthworm casts and in hydrogenous soil. The studies were conducted on variously mucked sedge-moss and alder peat at Kuwasy in the Biebrza river valley. Biomass of eathworms ranged from 42.7 to 119.7 g/m² season, whereas production of casts varied from 38 to 107 t/ha/season. Abundance of fungi in earthworm casts was 2-6 times greater than in mucked soil. Also greater development of cellulolytical microorganism and a higher activity of urease was recorded. On all the examined meadows there was noted a smaller (by ca 10-76 %) abundance of actinomycetes in casts than in soil.
Species composition, density and biomass of earthworms were studied on 84 differently managed and polluted sites (field, grassland, deciduous forest, coniferous forest, alluvial sites and mine spoil). All these sites are constantly monitored since a decade. In 13 sites amounts of heavy metals increased from: Cd – 3 to 6 mg kg⁻¹, Zn – 303 to 606 mg kg⁻¹, Pb – 95 to 317 mg kg⁻¹, Ni – 31 to 55 mg kg⁻¹, Cr – 58 to 80 mg kg⁻¹, and Cu – 59 to 114 mg kg⁻¹ soil, that is up to 2000, 880, 1090, 295, 320, and 520% higher, respectively, than in unpolluted field sites. Results show that metal pollution is not a dominating factor determining the species diversity and densities of earthworms. Remarkable differences in the distribution of ecological groups were found between biotope types. The endogeic species (Aporrectodea caliginosa Savigny, Aporrectodea rosea Savigny, Allolobophora chlorotica Savigny, Octolasion cyaneum Savigny) dominate in field and grassland habitats. The anecic species (Lumbricus terrestris L., Aporrectodea longa Ude), however, appear mostly in grassland. Epigeic species (Lumbricus rubellus Hoffmeister, Lumbricus castaneus Savigny, Dendrobaena octaedra Savigny) are found exclusively (in addition to the other two life forms) in grassland and the forest habitats. Differences in earthworm biomass between monitoring sites are not related to ecological risk assessment. These differences may be largely dependant on soil properties e.g. pH and organic matter. A matrix with the ecological requirements of earthworm species was developed.
The introductory lecture of the 5th, jubilee conference on „Ecological and economic significance of earthworms” presented the meaning of the research on earthworms and vermiculture from the point of view of popularizing the environmental basis of sustainable development. Educational actions in that field are important for popularizing the sustainable usage of soil, sustainable organic waste management (especially in small communes that cannot afford investing in organizing waste management), or improving the society’s health (the possibility of using manure vermicompost to produce the vegetables of high nutritivity). Presented problems and their earthworm-involving solutions, according to the law in force, are to be get familiar to the whole society by means of suitable education in schools of all types, the mass-media and various publications. The need of continuous education is noticed worldwide and therefore UNESCO pronounces the years 2005-2015 the decade of education for sustainable development. Need of continuous education is noticed worldwide and therefore UNESCO pronounces the years 2005-2015 the decade of education for sustainable development. The paper pointed out also what directions of research on the earthworms were being realized at various centers in Poland and presented during conferences „Ecological and economic meaning of earthworms”.
The studies were conducted in vegetative seasons of 1987 and 1988 at 7 experimental sites. 10 samples were taken at each site four times every season. Earthworms were extracted from soil by formalin method. The present results show a close similarity of the examined meadows in respect of earthworm density and biomass. In the view of the persent findings, the studied habitats cannot be regarded as degraded habitats where earthworms practically do not occur. Depending on season and site, earthworms excrete 10-100 t/ha d.w. of casts in vegetative season, it seems that 3.5-35% of soil in 0-10 cm layer pass yearly through alimentary canal of earthworms.
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