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11.
This paper focuses on environmental concerns regarding used antifreeze. It shows the results of laboratory respirometric tests conducted to evaluate the potential impact of antifreeze on activated sludge. In this first step of the study, only the components of virgin antifreeze were addressed, i.e. ethylene glycol, and antifoaming and corrosion inhibitory substances. The plateau resulting from oxygen uptake rate measurements of mixed liquor taken at the end of an aeration tank is used as a reference to evaluate the response of biomass to pulse injection of increasing dosages of new antifreeze, compared to that of formaldehyde, a known toxic compound. While 200 mg/L of formaldehyde steadily decreased the biomass activity (7 mg O2/Lh), there were no toxicity effects for doses up to 5000 mg/L of ethylene glycol from new antifreeze coolant (23 mg O2/Lh, compared to the initial 15 mg O2/Lh for the mixed liquor). It is estimated that ethylene glycol concentration in municipal wastewaters should be several order of magnitude lower then the 1000 mg/L shown to be tolerated by the biomass in this work, but at the present stage, the research does not provide enough information to recommend a definitive management scheme for antifreeze discharge. Many other management issues for used antifreeze must be addressed in future studies before any decision on tolerating sewer discharge in Mexico, as a transitory management option that will conciliate the actual practices with legality, can be made. 相似文献
12.
Farmers’ Perceptions of Climate Change and Agricultural Adaptation Strategies in Rural Sahel 总被引:17,自引:3,他引:14
Farmers in the Sahel have always been facing climatic variability at intra- and inter-annual and decadal time scales. While
coping and adaptation strategies have traditionally included crop diversification, mobility, livelihood diversification, and
migration, singling out climate as a direct driver of changes is not so simple. Using focus group interviews and a household
survey, this study analyzes the perceptions of climate change and the strategies for coping and adaptation by sedentary farmers
in the savanna zone of central Senegal. Households are aware of climate variability and identify wind and occasional excess
rainfall as the most destructive climate factors. Households attribute poor livestock health, reduced crop yields and a range
of other problems to climate factors, especially wind. However, when questions on land use and livelihood change are not asked
directly in a climate context, households and groups assign economic, political, and social rather than climate factors as
the main reasons for change. It is concluded that the communities studied have a high awareness of climate issues, but climatic
narratives are likely to influence responses when questions mention climate. Change in land use and livelihood strategies
is driven by adaptation to a range of factors of which climate appears not to be the most important. Implications for policy-making
on agricultural and economic development will be to focus on providing flexible options rather than specific solutions to
uncertain climate. 相似文献
13.
Dione Cheikh Tidiane Ndiaye Momar Delhomme Olivier Diebakate Cheikhna Ndiaye Birame Diagne Ibrahima Cisse Dame Hane Maoudo Dione Mame Mor Diouf Sitor Diop Abdoulaye Millet Maurice 《Environmental science and pollution research international》2023,30(2):2374-2391
Environmental Science and Pollution Research - Environmental pollution is one of the major problems facing human health, ecosystems, and biodiversity. This is particularly the case for water... 相似文献