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July-September, 2019

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Land Cover Change Monitoring In Egypt Using Satellite Imagery

Taher M.H. Yossif

ABSTRACT: An apt and effective automated methodology for monitoring land cover dynamics over time is of great importance to realize sustainable agricultural development. The present study focuses on the assessment of the trends and drivers of land cover change in Egypt for the last two decades (2000- 2019). An approach of multi-temporal mid resolution satellite images of ETM 2000, and OLI 2019 combined with visual interpretation, supervised classification and remotely sensed NDVI and NDWI images to enhance accuracy of land cover classification was used. Results showed that Egypt could be distinguished to several land cover classes; namely, “agro-forest areas”, “shrubs, grasslands and sparsely vegetated areas”, “cropland”, “wetland”, “artificial surfaces”, “bare land” and “water bodies”. Over the last two decades, there has been an improvement in land cover reached around 11976 km2 (1.2 % of the total land area), simultaneously with the degradation of around 1817 km2 (0.18 % of the total land area). The study showed a crucial evidence for a prominent increase in wetland and water bodies and the consequent hazards to the croplands. It is indicated that the application of multi-spectral satellite data proved inevitably efficient, reliable and fast methods and techniques.

[ FULL TEXT PDF 151-161 ] DOI: 10.36632/ije/2019.8.3.1

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Continuous detoxification of carcinogenic aromatic amines by activated sludge treatment

Samir I. Gadow, Habib Md. Ahsan and Yu-You Li

ABSTRACT: During anaerobic treatment of azo dyes containing wastewater, carcinogenic aromatic amines are often produced. Therefore, a plexiglass lab-scale continuous bio-reactor was built for anaerobic effluent of azo dye degradation contained aromatic amines. The system was operated at 35±1oC temperature and pH was maintained between 7.6- 7.9 for over 4 months with an effective volume of 5 liters and hydraulic retention time (HRT) of 72, 48 and 24 h. The results of electrospray ionization (ESI) analysis showed that the main by-products of methanogenesis of C.I. acid red 88 were 2- naphthylamine (2NA) and 4-Amino-1-naphthalene sulfonic acid. Our results suggested that the 2NA cannot be used as the sole carbon and energy source because of its toxicity at substrate level concentrations and the ratio of MLVSS/MLSS was decreased from 0.7 to 0.3 with 3% of COD removal. On the other hand, during the recovery period, approximately 20 days acclimation with glucose (400 mg 1-1) as co-substrate was required to obtain an enrichment culture able to degrade 2NA and other aromatic amines. The maximum 2NA mineralization reached 75.4% removal at HRT of 24h and the system is expected to have a better economic performance under HRT of 24h.

[ FULL TEXT PDF 162-170 ] DOI: 10.36632/ije/2019.8.3.2

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Environmental assessment of natural radioactivity in Mahamid phosphorite and the related phosphatic fertilizers

Ibrahim H. Zidan

ABSTRACT: The natural radioactivity sourced from Mahamid phosphorite and the related fertilizer, single super phosphate (SSP), was measured hence, some radiation indices were calculated to assess the environmental impact of these materials.The activity concentrations were measured in Bqkg-1 based on the recorded activities of the 226Ra, 232Th and 40K radioactive nuclides using the High-Purity Germanium detector (HPGe). The calculated radiation indices included; Radium equivalent activity (Raeq), the absorbed dose rate (D), the annual effective dose (Eff. D.), the internal hazard index (Hin.), the external hazard index (Hex.), gamma index (Iɣ), alpha index (Iα) and Excess lifetime cancer risk (ELCR). All the resulted values were compared with the permissible limits of the corresponding indices as internationally recommended. Although the fabrication process of the SSP fertilizer caused significant reduction in the activity concentration relative to the phosphate source, but both materials commonly appeared as probable additional source for radiation risks for both the surrounding environment and the public. Accordingly, some recommendations were delivered to enhance the radiation protection issue.

[ FULL TEXT PDF 171-179 ] DOI: 10.36632/ije/2019.8.3.3

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