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Urban growth is a prevalent challenge in many countries as it causes unexpected changes in land-uses of surrounding areas of cities and endangers the environment and natural resources. Thus, spatial planners and environmental managers always look for the models that simulate the expansion of urban land-use, and enable them to prevent unbalanced expansion of cities, and guide the developments to the desired areas. Several methods have been devised to simulate the dynamics of land-use development. However, the complexity of urban growth is recognized as a major barrier for such simulation methods. Agent-based models as a dynamic bottom-up approach use the real actors of land-use development as their basic components. Thus, such models have found popularity in simulating land-use development and urban sprawl modeling. This paper introduces a new agent-based model used for simulating urban land-use development in our study area located in Qazvin province, Iran. The orchards that encompass the western, eastern, and southern sides of Qazvin city are the most sensitive zones in the study area. The model uses 2005 data for the purpose of calibration and 2010 data for the goal of evaluation. A Kappa accuracy of 82.78% was finally achieved for the predication of the observed developments. Also, three zones of residential developments around Qazvin city were found to be endangered. Orchards located on the eastern side of Qazvin city are exposed to destruction and conversion into urban areas. The calibrated model can also be used as a useful tool for predicting future land-use developments and for recognizing endangered environmental zones.
The aim of the research was to assess the chemical composition and sanitary state of sandboxes in Krakow. Samples of sand were collected from 42 sandboxes located on playgrounds in housing estates and municipal (urban) parks. In the samples the following were determined: reaction, organic matter and the content of total and soluble forms of several elements. The sand in the analyzed sandboxes had highest content of Zn, while the concentrations of other metal appeared in the following decreasing order: > Pb > Cr > Ni > Cu > Cd (total forms) and Zn > Pb > Cu > Ni > Cr > Cd (soluble forms). The highest potential for ingesting heavy metals by humans due to accidental consumption of sand was found for Zn, followed by Pb > Cu > Ni > Cr > Cd. Children were at a higher risk of exposition to heavy metals than adults. On no occasion, the permissible limits of heavy metals for urbanized and built-up areas (group B) – set up by the regulation of the Minister for Environment on soil and earth quality – were exceeded. The same applies to the threshold levels of contaminants established for soils polluted by man-made sources. However, the sandboxes were found to be in poor sanitary conditions.
Soils and ground waters have been extensively exposed to pollution by heavy metals from various anthropogenic sources. The presence of these metals in soils poses a significant environmental hazard, and one of most difficult contamination problems to solve. Description of some sorption and migration phenomena involving Pb, Zn, Ni and Cu in the surface layer of soil and sewage sludge compost was the primary objective of this work. A wide range of pH (3.0 - 5.5) of simulated acid rains, used to study the elution of metals from these matrices allowed a qualitative description of these metals' behaviour.
The aim of the study was to investigate the correlation between the level of reactivity in conjunctival provocation test and conjunctival symptoms that develop during the pollination season in grass allergic patients. Conjunctival provocation test with grass pollen allergens was performed in 22 patients suffering from pollinosis. During grass pollination season all patients monitored their symptoms with Symptoms Score Cards. A parallel measurement of the level of grass pollen count was carried out on a daily basis by volumetric method. The mean grass pollen count which triggered the reaction in individual patients depended on the results of conjunctival provocation test. The lowest pollen count level was observed in cases of patients with positive conjunctival provocation test at low allergen extract concentration of 160 and 500 BU/ml, whereas the highest count in cases of 1,600 BU/ml. The difference between the results was found to be statistically significant. A threshold grass pollen concentration for conjunctival symptoms was established at the level of 22 grains/m3. We conclude that the patients with pollinosis and high reactivity in conjunctival provocation test develop conjunctival symptoms earlier during grass pollination season than the patients who are characterised by lower reactivity during conjunctival provocation test.
Environmental hazards posed by unintentional and excessive penetration of chemical substances into water, air and soil is noticeable in its harmful effects on plants, free range animals, quality of environment components and biodiversity in general. The chemicals used in agricultural practices enter the food chain most frequently through their application to soil or crops. Regarding the employment of pest-control preparations, rodenticides play an important role in controlling harmful rodents. The present paper reports the investigation of residues fromKumatox Z rodenticide preparation with an active ingredient – warfarin – applied to cereal crops. Kumatox Z is a rodenticide bait containing the active ingredient warfarin in 0.05% concentration. The preparation was employed in the form of cereal baits to soil surface. The research results showed the presence of warfarin residues in the treated soil and cereals grown over there. Determination of residues was carried out by HPLC; interestingly, they were found in the soil even after three years.
Fast development of the electronics industry and an eminent value of obsolescence of the electronic productions conduce to the uninterrupted production of great amounts of electronic waste or e-wasteworldwide. Due to the frequent commingling of a wide range of reusable, or recyclable, and non-recyclable surplus electronics, the term "e-waste" infer all sorts of these leftovers. Even though the economic benefits are potentially enormous, only a small proportion of the electronic waste is being recycled all around. There is a transaction cost associated with the recycling process due to the environmental protection regulations, hence economically less attractiveat the industry level in developed nations. However, to the least developed nations where owing to low living standard the demand for the better quality environment is low, even nonexistent, recycling e-waste has become a livelihood earning opportunity. The study intends to interpret the socio-economic consequences of e-wastes by focusing the detrimental effects that it have created in China and Ghana, and attempts to outline what developing nations like Bangladesh can do to prevent or reduce the harmful consequences of it.
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