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The new look at the forest economy takes into considerationmaximum protection of forest ecosystems, first of all. The purpose of the research was to estimate the influence of wood harvesting and skidding technologies on forest environment, particularly on soil and remained stand. The traditional wood harvesting and skidding technology (compact sawing machine, tractor with winch) was more friendly for soil environment than the newest technology (harwarder). Decrease of the negative influence of engineering wood harvesting and skidding process on forest environment is possible through application of both technologies and technical means correctly selected for the purpose. Besides, the operator’s practice is of a significant meaning.
There has been a growing interest over the last years in techniques using alternative and pharmaceutical plants due to their wide potential applications. These species are characterised by valuable and multidirectional usable features, due to which their practical application is superior to their physiognomic features. These plants may provide a raw material for production of medicines, cosmetics or may be used for animal feeds. Moreover they may be used as ornamental, melliferous and energy plants. Owing to their generally low soil requirements they are used in the reclamation of degraded land. Among the species characterized by multidirectional use are Silphium perfoliatum, Helichrysum arenarium and Stevia rebaudiana. These plants are characterized by a high content of active compounds and a number of pro-health characteristics. Because raw materials for production of medicines and cosmetics should be standardized, cultures maintained under controlled conditions are a good source of seedlings.
The main goal of this article is to attract attention of junior scientists interested in evolutionary and ecological parasitology, to some very interesting articles dealing with the methodology of such investigations. The authors review some problems related to terminology used in the studies of host-parasite relationships and then recapitulate the subjects of five articles, in which new indices of the range and characters of hosts specificity are proposed. These are: the article of Caira et al. (2003), Poulin et Mouillot (2003, 2005), Krasnov et al. (2011) and Poulin et al. (2011).
Background. Monogenean parasites from mixohaline areas of the South Atlantic coast of Argentina are very poorly reported. The aim of this paper is report a new host and locality for Absonifibula bychowskyi, a monogenean confined to fish living in estuarine areas. Some ecological considerations about the host-parasite relationship are also discussed. Materials and Methods. Parasites collected from whitemouth croaker, Micropogonias furnieri (Desmarest, 1823) (Actinopterygii: Sciaenidae), were studied from fixed- and live specimens, with standard procedures used in parasitology. Prevalence, mean intensity, and abundance of parasites were calculated and related to the host body size. Spearman′s rank correlation coefficient was calculated to determine possible correlations between host length, parasite intensity, and prevalence. Results. Absonifibula bychowskyi (Monogenea: Diclidophoridae) Lawler et Overstreet, 1976 is reported for the first time from the gills of whitemouth croaker, at the Samborombón Bay, a mixohaline area in the Buenos Aires Province, Southwest Atlantic Ocean. The parasite was found only in juveniles of M. furnieri that use the Samborombón Bay as the main estuarine nursery ground area. When the croaker migrated seawards, A. bychowskyi disappeared from the gills may be related to the increased salinity. Conclusion. This is the first record for Absonifibula bychowskyi in the Southwest Atlantic and M. furnieri. (It constitutes a new host record.) The presence of A. bychowskyi in M. furnieri could be indicative of the origin of the fish.
This paper presents the first extensive data on the helminth community of the wood mouse Apodemus sylvaticus in a coastal sand dune area in Portugal. The 557 hosts analysed in this study were trapped seasonally between autumn 2002 and summer 2005 across 6 habitat types. Twelve helminth species were detected among which, Taenia parva larvae, Angiostrongylus dujardini, Heligmosomoides polygyrus, Syphacia stroma and S. frederici constitute the component species, accounting for 98.7% of all worms. H. polygyrus was the most prevalent helminth parasite. Species richness varied according to habitat and season. The highest species richness was found in sand dunes during winter whereas the lowest was detected along lake margins also during the winter. Some differences in prevalence and mean intensity values were found in relation to year (T. parva larvae and H. polygyrus), habitat (A. dujardini), season (T. parva larvae, H. polygyrus, A. dujardini and S. stroma) and host sex (T. parva larvae and S. stroma). These differences are discussed both in view of the host’s biology and habitat characteristics.
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