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The research was carried out on two meadow objects with clearly different geo- chemical conditions of the soil environment (a small Ciemięga river valley and meadows surrounding three lakes of Uściwierz Bikcze and Nadrybie). Soil and plant samples (6 species - mainly meadow grasses) were taken in 2 vegetation periods - 1995 and 1996. The results showed that soils from the fertile valley of the Ciemięga river, as the ones derived' from low peat silted-up by carbonates and loess silt, had a neutral reaction and a great content of basic components - especially calcium compounds. Boggy soils occurring in the second object, derived mainly from weakly decomposed low or transitional peat, had low ashness and a very acid reaction. In the chemical composition of almost all plant species there is a clearly more favourable situation in the samples from the Ciemięga river valley meadows. That allows to conclude that the trophism of meadow habitats to a great degree depends on the amount of Ca in the environment, because Ca - by deciding on the soil reaction - indirectly affects the mobility and, therefore, also availability of other nutrients for plants.
The results of measurements of susceptibility to biodegradation and the effect of storage in soil on the mechanical properties of thermoplastic starch films obtained from blends of starch, glycerol and emulsifiers. Studies have shown a varied influence of the blend compositions, extrusion conditions and storage on the scope and efficiency of biodegradation of the products.
In the presented studies, an attempt has been made to utilise enzymatic indicators for the estimation of soil environment reaction to the applied differentiation of organic fertilizers and maize (Zea maysL.) cultivation.The two-year experiment was held on a field. In different development stages of maize, the activities of protease, dehydrogenase and acid phosphatase were determined in the soil. The activity level of the selected enzymes was defined using the spectrometrical method. The results obtained from the studies, show that applied organic fertilization, as well as the cultivation of soil had only a minor effect on the activity of the analysed soil enzymes. In case of dehydrogenases, it was found that their activity in the time of the experiment was the highest after the manure incorporation into the soil. In case of phosphatase, its highest activity was recorded in the soil fertilized with sewage sludge (5 t d.m. ha⁻¹ year⁻²).
Corms of Colchicum autumnale L. (meadow saffron) from plants growing on soils developed from five parent materials (melaphire, serpentine, sandstones, limestone and marls) were collected and analysed to evaluate their colchicine content as well as metal levels (Fe, Mn, Zn, Cu, Pb, Co, Cd, Ni and Cr). For all locations, (mountainous regions in SW Poland far from pollution sources) where corms were collected, soil samples were taken. In the soil samples, the concentration of elements (Fe, Mn, Zn, Cu, Pb, Co, Cd, Ni and Cr) was analyzed and also soil pH, organic matter content and sand, silt and clay content were determined. The results of principal component analysis (PCA) showed that the concentrations of metals in melaphire (except Cr), sandstone and serpentine soils were higher than those in limestone and marl soils. Meadow saffron corms tended to take up a higher amount of Fe and a lower amount of Co and contained in their tissues a higher amount of colchicine in melaphire soil and some sandstone soils than those in limestone and some marl soils. The concentrations of Co, Mn and Zn in corms at limestone site and Ni and Cd in corms at serpentine site and some marl sites were higher than those in other sites. The results of stepwise regression analysis showed that colchicine corm concentration as well as corm Fe content increased with increasing soil Fe, Mn, Zn, Co, Cu, Pb and Cd contents and that corm Fe content has a positive effect on the production of colchicine, whereas corm Co, Mn, Zn, Ni and Cd negative. The corm Fe, Mn, Zn, Co, Ni and Cd concentrations appeared to be the main factors determining the variation pattern of colchicine in C.autumnale corms. The variation explained by these selected variables was higher (79%) than those explained by selected soil variables (53%).
Life form spectrum is an informative parameter in a comparative analysis of ecological structure of Collembola communities, and a valuable indicator of conditions of soil environment. This suggests a search of adequate methods of its determination. In the present study, two methods of evaluation of life form spectra in springtail communities are compared. A usual approach is a determination of the species composition and abundance, with a subsequent formal distribution of the species present among the life form categories of a chosen system, e.g. among epedaphic, hemiedaphic and euedaphic life forms considered as dwellers of litter surface and upper horizon, of litter depth and topsoil, and of soil horizon, respectively (Hopkin 1997). By this method (A) all the specimens of a given species are attributed to the same life form. However, species populations contain juveniles with smaller body size, thinner cuticle and weaker pigmentation, which tend to be more sensitive to environmental constraints and to dwell deeper in soil than adults. Therefore the attribution of juveniles and adults of a given species to the same life form may not be accurate. Another approach is a direct attribution of a life form category to each collembolan individual during the determination process, according to the visual assessment of its morphological characters (body size and development of pigmentation, number and pigmentation of ommatidia). In that case representatives of a given species might be attributed to more than one life form category, e.g. adults to epedaphic whereas juveniles to hemiedaphic life form, or to hemi- and euedaphic life form, respectively (method B). To compare both methods, mass collembolan material of a microcosm experiment carried out in a beech-oak forest at Mikolajki Research Station (NE Poland) and aimed at investigation of mesofauna/ earthworm interactions, was used. The comparison showed a statistically significant bias between the spectra of Collembola life forms estimated by methods A and B: the latter spectrum was shifted to the favour of euedaphic forms. The range of the bias was larger in soil than in litter horizon. Method B is suggested to be closer to a real life form distribution in a collembolan community and may be used for corrections of the data obtained by the traditional taxonomic method A.
This research presents an evaluation of the effect of forecrops (after papilionaceous, root and cereal plants) on the health of the strawberry of the Senga Sengana variety. The diagnostics of diseases were carried out on the basis of symptoms occurring on those parts of the plant above the ground, as well as on the roots, and additionally on the basis of mycological analysis. The results obtained indicate that the main cause of the strawberry dying back and the occurrence of disease symptoms were the species of Fusarium genus after root plant fore crops; Fusarium spp.. Alternaria spp., Botrytis spp., Cylidnrocarpon spp., Phoma spp., Rhizoctonia spp., and Verticillum spp. after papilionaceous plant forecrops and Fusarium spp., Alternaria spp., Pythium spp., Rhizoctonia spp. after cereals.
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