Groundwater comprises a large portion of irrigation for California's agriculture, and sustains a wide diversity of ecosystems as well as consumptive use, but pumping is occurring faster than replenishment. At the sam...Groundwater comprises a large portion of irrigation for California's agriculture, and sustains a wide diversity of ecosystems as well as consumptive use, but pumping is occurring faster than replenishment. At the same time, contaminants from fertilizers and pesticides are infiltrating into the groundwater, becoming increasingly concentrated as water is extracted. It compared space-based observations of groundwater anomalies from California's San Joaquin Valley using the GRACE (gravity recovery and climate experiment) against measurements of 42 organic and inorganic chemicals from 41,667 wells in the valley from 2003 to 2010. It compared Arsenic, Boron, Cadmium, Chloride, Selenium, Trichloroethylene, and TDS (total dissolved solid) concentrations with the groundwater storage anomaly from 2003 to 2010. The results show strong correlations for groundwater depletion against increasing chloride (r2= 0.78, p 〈 0.05) and boron (r2 = 0.88, p 〈 0.05). This indicates increasing contaminant concentrations while groundwater was depleting over the last eight years. Solubilization by complexation with Cl, CO3 and/or organic chelates may account for the increasing concentration of some heavy metals when groundwater depletion occurs. These results are the first to link space-based groundwater mass change with groundwater contaminant concentration change.展开更多
This study aimed at the geographical variation in methods of processing shea butter that has been passed on from generation to generation and storage procedures (materials and containers used/perceived shelf life of ...This study aimed at the geographical variation in methods of processing shea butter that has been passed on from generation to generation and storage procedures (materials and containers used/perceived shelf life of the products used for preservation and local perceptions about rancidity). Little variation was found in indigenous processing methods, utilization and storage across most of the three regions. Only among the Dagomba tribe in the Northern region did women intentionally use shrubs to add yellow colour to butter particularly that for the market. The use of onions and lemon/lime leaves to prevent rancidity and also improve the taste and smell of butter was found to be practiced by only one missionary group. Perception about shelf life of the butter was found to vary widely among the processors and consumers (3 months to 2 years). Though this was the main focus of the study, most of the indigenous processors and consumers apart from the missionary group had little experience as far as this problem was concerned. This was due to the fact that most of them consumed the butter within one or two months after processing and so the product is not kept long enough to give any appreciable signs of rancidity.展开更多
文摘Groundwater comprises a large portion of irrigation for California's agriculture, and sustains a wide diversity of ecosystems as well as consumptive use, but pumping is occurring faster than replenishment. At the same time, contaminants from fertilizers and pesticides are infiltrating into the groundwater, becoming increasingly concentrated as water is extracted. It compared space-based observations of groundwater anomalies from California's San Joaquin Valley using the GRACE (gravity recovery and climate experiment) against measurements of 42 organic and inorganic chemicals from 41,667 wells in the valley from 2003 to 2010. It compared Arsenic, Boron, Cadmium, Chloride, Selenium, Trichloroethylene, and TDS (total dissolved solid) concentrations with the groundwater storage anomaly from 2003 to 2010. The results show strong correlations for groundwater depletion against increasing chloride (r2= 0.78, p 〈 0.05) and boron (r2 = 0.88, p 〈 0.05). This indicates increasing contaminant concentrations while groundwater was depleting over the last eight years. Solubilization by complexation with Cl, CO3 and/or organic chelates may account for the increasing concentration of some heavy metals when groundwater depletion occurs. These results are the first to link space-based groundwater mass change with groundwater contaminant concentration change.
文摘This study aimed at the geographical variation in methods of processing shea butter that has been passed on from generation to generation and storage procedures (materials and containers used/perceived shelf life of the products used for preservation and local perceptions about rancidity). Little variation was found in indigenous processing methods, utilization and storage across most of the three regions. Only among the Dagomba tribe in the Northern region did women intentionally use shrubs to add yellow colour to butter particularly that for the market. The use of onions and lemon/lime leaves to prevent rancidity and also improve the taste and smell of butter was found to be practiced by only one missionary group. Perception about shelf life of the butter was found to vary widely among the processors and consumers (3 months to 2 years). Though this was the main focus of the study, most of the indigenous processors and consumers apart from the missionary group had little experience as far as this problem was concerned. This was due to the fact that most of them consumed the butter within one or two months after processing and so the product is not kept long enough to give any appreciable signs of rancidity.