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Sea-buckthorn is an important species especially in terms of land reclamation, but it has also an appreciable commercial value. The aim of this review paper was to highlight the multiple uses of this shrub species across world. Data regarding taxonomy, chorology, ecological requirements and biological characteristics were also presented. Special attention has been given to the role of sea-buckthorn in land reclamation. The importance of this species is expected to increase in the future due to its high ecological amplitude and biological characteristics that make it suitable for many types of land, including arid terrains.
The aim of this papers is to discuss the expected effect of increasing phosphorus accumulation in cultivated soils. The global consumption of phosphorus fertilisers since 1954 exceeded 1 billion tons of P2O5, and about a half of this amount was used in European countries. More than 95% of mined phosphate rocks are provided to food production. That resulted that the total phosphorus content in agricultural used soils was doubled or tripled in European countries up to now. A further increase of phosphorus accumulation in the- cultivated soils would conduct to eutro- phication of water and terrestrial ecosystems. The euthrophication of surface water is rather good known phenomena, but the euthrophication of terrestrial ecosystem need broader identification. Main sources of phosphorus in environment is food production and consumption. In agriculture, a renewed attentions is required to ensure that phosphorus in modern farming systems is managed in a manner which is sustainable from the point of view of both agriculture and environment. The mitigation of eutrophication originated from phosphorus accumulation in agricultural soils could be achieved only on scientific basis followed with country and regional abatement programs.
The paper contains the results of eight-year-long studies on the runoff of nitrates from heavy soils used as croplands. The runoffs of nitrates from a drainage catchment and a catchment drained with ditches were compared. The drainage system was found to carry away twice as much water, with a five-fold higher concentration of nitrates and 20-fold higher load of nitrates, than the system of ditches. High runoff of nitrates (22 kg ha-1 annually) from the soils drained by drains was distributed quite evenly throughout the year, with maximum peaks in March and June. Nitrate runoff through the system of ditches was low (1.15 kg ha-1 annually), reaching maximum peaks in March and April (62% of the load), but disappearing in the summer.
The study was located in a Scots pine plantation established on the outer dumping ground of the Lignite Mine in Bełchatów using different seedling production methods. The seedlings used in the study were raised in a bare-root forest nursery, a foil greenhouse and a container nursery mycorrhized and not-mycorrhized with the fungus Hebeloma crustuliniforme. The survival of seedlings in the first year after planting, their growth based on height and root collar diameter measurements and the degree of root mycorrhization were determined. The Scots pine seedlings growing under the outer dumping ground conditions were evaluated for their usefulness in silvicultural practice taking account of the method of their production.
Research concerning the influence of sludge and ash composts on the heavy metal contents in reclaimed soil was conducted on experimental plots located on the area of mechanically devastated and intensively acidified soil. Once the plots of 15 m² surface area were deacidified with floated lime, 6-month-old composts were used on each in the ratio of 3, 6, and 9% of dry matter (90, 180 and 270 t·ha⁻¹) in the following variations: compost of municipal sewage sludge; compost: sludge (80%) + ash (20%); compost: sludge (70%) + ash (30%). Fertilizing the devastated soil with composts examined brought about an increase in the contents of analysed heavy metals, proportional to the dosage, but the values were still lower than the permissible levels for soils where sludge is used both for recultivation and agriculture. Taking into account metals present in the soil of 0-20 cm layers, the composts examined fell into following series: Pb, Cu, Zn: sludge + 30% ash compost > sludge compost > sludge + 20% ash compost; Cd: sludge + 30% ash compost > sludge + 20% ash compost; sludge compost.
The release of sludge-born bacteria and their further subsurface transport was studied. The migration of bacteria was investigated in column experiments which were carried out under the conditions correspond­ing to naturally occurring extreme rainfall. Coal fly ash as well as coarse and medium grained sand, whose properties are similar to the soils present in degraded areas, were used as column beds. Sewage sludge was applied on the top of column beds in the quantity corresponding to the best land-reclamation practice. Clos­tridium perfringens and fecal coliforms were used as bio-tracers of fecal pollution. The obtained results showed the dynamic of bacterial cells' leaching from the sludge matrix, and the dynamic of their infiltration through the column beds to the effluents. The bacterial breakthrough curves obtained for the fly ash and for the sandy media differ significantly, reflecting the differences in transport processes and in the survival of bacterial cells. It has been found that the fly ash layer, whose thickness equals 0.80 m, can be regarded as an effective filter, which limits bacterial migration. When sludge is applied to the sandy soils, about 0.02% of the initial number of sludge bacteria can migrate downwards the sandy layer and can cause contamination of potentially shallow aquifers.
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