Drinking water supply for the Main Ethiopian Rift (MER) area principally relies on groundwater wells and springs and is characterized by fluoride contamination. New analyses reveal that the F^- geochemical anomaly is ...Drinking water supply for the Main Ethiopian Rift (MER) area principally relies on groundwater wells and springs and is characterized by fluoride contamination. New analyses reveal that the F^- geochemical anomaly is associated with other potentially toxic elements such as As,B,Mo,U,Al,Fe and Mn. Particularly,35%of the 23 investigated groundwater wells and 70%of the 14 hot springs(and展开更多
This study shows for the first time a chemical and morphological characterization of agricultural aerosols released during three important agricultural operations： threshing, plowing and sowing. The field campaigns w...This study shows for the first time a chemical and morphological characterization of agricultural aerosols released during three important agricultural operations： threshing, plowing and sowing. The field campaigns were carried out in the eastern part of the Po Valley, Italy, in summer and autumn 2009. The aerosol particles were sampled on quartz fiber filters and polytetrafluoroethylene membranes in order to allow Inductively Coupled Plasma Mass Spectrometry （ICP-MS） analysis and Scanning Electron Microscopy equipped with an Energy Dispersive X-ray Spectrometer （SEM-EDS） investigations, respectively. The organic carbon mass concentrations were measured with a Sunset Laboratory Dual-Optical Organic Carbone/Elemental Carbon （OCEC） Aerosol analyzer. The morphological and chemical analyses by SEM-EDS allowed recognizing four main particle classes： organic, silica, calcite and clay minerals. The organic particles contribute to both fine and coarse aerosol fractions up to ca. 50% for all three agricultural activities. This was also confirmed by OCEC analysis for fine fraction. Most of the agricultural aerosols, about 60%, were single particles and the remaining 40% were agglomerations of particles. The ICP-MS results showed that threshing and plowing produce more aerosol particles than sowing, which was characterized by important amounts of clay minerals produced from land soils.展开更多
文摘Drinking water supply for the Main Ethiopian Rift (MER) area principally relies on groundwater wells and springs and is characterized by fluoride contamination. New analyses reveal that the F^- geochemical anomaly is associated with other potentially toxic elements such as As,B,Mo,U,Al,Fe and Mn. Particularly,35%of the 23 investigated groundwater wells and 70%of the 14 hot springs(and
基金This work is part of the MINNI (Integrated National Model in support to the International Negotiation on Air Pollution) projectfunded by the Italian Ministry of the Environment and carried out by ENEA
文摘This study shows for the first time a chemical and morphological characterization of agricultural aerosols released during three important agricultural operations： threshing, plowing and sowing. The field campaigns were carried out in the eastern part of the Po Valley, Italy, in summer and autumn 2009. The aerosol particles were sampled on quartz fiber filters and polytetrafluoroethylene membranes in order to allow Inductively Coupled Plasma Mass Spectrometry （ICP-MS） analysis and Scanning Electron Microscopy equipped with an Energy Dispersive X-ray Spectrometer （SEM-EDS） investigations, respectively. The organic carbon mass concentrations were measured with a Sunset Laboratory Dual-Optical Organic Carbone/Elemental Carbon （OCEC） Aerosol analyzer. The morphological and chemical analyses by SEM-EDS allowed recognizing four main particle classes： organic, silica, calcite and clay minerals. The organic particles contribute to both fine and coarse aerosol fractions up to ca. 50% for all three agricultural activities. This was also confirmed by OCEC analysis for fine fraction. Most of the agricultural aerosols, about 60%, were single particles and the remaining 40% were agglomerations of particles. The ICP-MS results showed that threshing and plowing produce more aerosol particles than sowing, which was characterized by important amounts of clay minerals produced from land soils.
