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  • Vermicomposting of communal sewage sludge
    52-60
    Views:
    120

    The proper management of communal sewage sludge is a priority aim in today’s environmental protection. Among the possible technologies one environmentally sustainable sludge treatment technology can be the vermicomposting of communal sewage sludge. Before the successful operational level vermicomposting is absolutely necessary to investigate the process of vermicomposting in laboratory controlled conditions. In our studies vermicomposting of communal sewage sludge was carried out by comparing two earthworm populations in laboratory. During 6-week experimental period the temperature (with soil thermometer) and the redox potential (with ORP portable device) were measured every other day. The weekly, measured, basis parameters were the compost visual appearance, color and smell, pH (H2O), dry matter content, organic matter content, EC (conductivity), from which the total salt content can be calculated, total nitrogen content, phosphorus content (P2O5), potassium content (K2O), calcium and magnesium content, humus content (H%), determining the humus quality according to Hargitai’s method and dehydrogenase enzyme activity. It can be concluded from the results that the vermicomposting of studied communal sewage sludge has started and keeps going. The basic physical and chemical parameters (e.g. temperature, humus quality and quantity) support the changes. The results of humus quality and quantity which are priority variables of agriculture use show average increasing despite the initial recession. The changes of the important chemical parameters (nitrogen, phosphorus, potassium) in nutrient management were developed favorably. In our presentation the previous laboratory results are described.

  • Determination of three small streams’ chemical water quality in Budapest
    69-75
    Views:
    111

    The location and development of cities has been influenced basically by various environmental factors. However, the relationship is bilateral, because not only the environment can affect the city, but the city can affect the environment in different ways, depending on recovery. This is especially true in the case of large cities such as Budapest where the different geological, geomorphological, hydrological, soil and bio-geographical conditions can be changed in very small areas, which implies that land use can be also modified as well. The aim of our study was to determine the chemical water quality of three small streams in Budapest which have same water flow and compare the field and the laboratory test results. Between many natural characteristics of these streams similarity is evident, however, several differences were found between the watersheds in terms of human land use. Statistical data analysis was performed as well, which was the aim to explore the relationship between the parameters. Overall, according to our study it can be concluded, the small streams have similar water chemical properties, but some parameters need special attention in the future, because the investigated small streams can be categorized into polluted and sometimes heavily polluted category.