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Spiders are considered to be sensitive to habitat pollution, but the effect of sulphur contamination on spider communities is poorly known and studied, although the impact of sulphur can be realized by the changes of soils and forest community. This work examined the diversity of ground-dwelling spiders in sulphur-contaminated habitat among three types of studied biotopes (deforested area, thicket, spruce forest) in the area of the Karkonosze Mountains (Sudetes Mountain System) in Poland. In the late 1970s and 1980s, a large-area forest decline in Sudetes Mountains, mainly derived from industrial emissions caused drastic changes in abiotic environment leading to the fundamental forest ecosystem transformation. The results of these damages were studied directly after the forest decline took place. Nowadays, more than 20 years after the ecological disaster, 13 sites were chosen according to habitat type to study the long-term impact of sulphur on spiders. The sites with high and low sulphur content in soil were not significantly different with regard to spider species diversity, although the most deforested sites were characterized by the lower values of sulphur. The only significant positive correlation found was the dependence between spiders' diversity and plant richness. All studied habitats were characterized by different community structure, although thickets was the most diverse with predomination of Linyphiids and Lycosids.
Producer groups are a form of integration of horticultural producers. The main advantages resulting from the association include lowering production costs, increasing the impact on the market and gaining competitive advantage. Despite these benefits, many producers still do not want to associate. The aim of this study was to investigate the types of prejudices discourtaging horticultural farm owners from organizing themselves in groups of producers in the community of Błędów. The study was conducted in 2012, among the owners of horticultural businesses, not belonging to the producer groups. The factors that may act as a barrier to joint action were examined. According to the survey, 38% of respondents do not want to belong to a group, more than half of respondents are undecided, while only 16% expressed a desire for membership in the group. The main barriers of association may include economic, administrative, and psychological factors.
Taxonomic and biological-ecological information as well as literature pertaining to the eleven Polish representatives of glossiphoniid leeches are summarized. Taxonomic status of many species is unclear, and data on their life histories are often fragmentary. The existence of several different conflicting systems of glossiphoniid classification indicates that the taxonomical value of characters is unclear. The family requires a thorough modern revision. A new generic-level classification of the family is needed. Data on behaviour and life cycless of most species should be supplemented; anatomical variation and differences between the purported forms of glossiphoniid species should be re-examined. A detailed study on the life cycles and variation of the Polish members of the Glossiphoniidae would provide new and valuable data and would allow at least for proposing a good, modern standard of species description without which a world-wide revision is hardly possible.
We studied a landfill where toxic sludge derived from copper ore production is deposited. These types of landfills pose a threat to the surrounding environment because of the complete lack of vegetation and dust emission. Thus, the problem refers to the future recultivation of these areas. In order to improve the quality of the affected environment, thus allowing plants development, we applied biopreparations containing biosurfactants and microorganisms for the following plant species: Zea mays, Lupinus luteus, Pisum sativum, Avena sativa, and Sinapsis alba. We studied their influence on both germination and plant growth. It was found that applying biosurfactants before germination stimulates all studied seeds. This effective technique could be used for the reclamation of soil contaminated by post-flotation waste. However, the usefulness of biosurfactants for further plant growth was not proved.
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