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Mohamed El-Sayed Mohamed Mahgoub Nico Peter van der Steen Khaled Abu-Zeid Kala Vairavamoorthy 《Journal of Cleaner Production》2010,18(10-11):1100-1106
Urban water authorities and water planers in many countries are struggling to satisfy the growing urban water and sanitation demands, while at the same time achieving sustainability of the urban water system. This research focused on the assessment of the environmental impact of today's Alexandria's urban water system and on the identification of options to improve the sustainability of the system. Therefore, a life cycle assessment (LCA) methodology was used. The urban water system was modelled using SimaPro software, and the impacts of various options on the system were analyzed based on the Eco-indicator 99 assessment method. The results show that the highest impact in today's system is generated by the disposal of primary treated wastewater (68% of the total impact) and by high-energy-consuming water treatment plants (18% of the total impact). The research assessed different scenarios for improving the environmental performance of the system and a paradigm shift (decentralization and separation at-source of different kinds of household wastewater) was found to be the preferred long-term scenario. 相似文献
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Effects of sheep and goat grazing on the species diversity in the alpine meadows of Western Himalaya 总被引:3,自引:0,他引:3
This paper deals with effects of sheep and goat grazing on plant species diversity, species richness and species composition in two important conservation areas of the Western Himalaya; the Valley of Flowers (VOF) National Park and the Great Himalayan National Park (GHNP). The VOF is a completely Protected Area as it is devoid of livestock grazing whereas, 20,000 sheep and goats annually graze in GHNP. Both the National Parks possess sub-alpine and alpine vegetation that is distributed in 13 major habitat types. Present investigations indicate that all the habitat types in VOF are higher in plant species diversity and richness compared to habitat types in GHNP. Similarly, all three eco-climatic zones in VOF are higher in species diversity and richness compared to GHNP. Species diversity also decreases with increasing altitude in both the National Parks. The findings of this study are discussed in the light of the management and conservation of alpine meadows of the Western Himalayas. 相似文献
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