ABSTRACT
A simple colorimetric method has been developed for the detection of lead (Pb2+) in water samples using lipoic acid-functionalized gold nanoparticles. The lipoic acid-functionalized gold nanoparticles are induced to aggregate in the presence of the Pb2+ which results in a change in the color of the functionalized gold nanoparticles. The change in color and the amount of Pb2+ producing the change could be monitored via UV-visible spectrophotometry. A good correlation coefficient of 0.9927 was obtained for the calibration curve of the colorimetric method. The method was applied in the determination of Pb2+ in water samples and the results compared to that of measurement carried out with Atomic Absorption Spectroscopy.
ABSTRACT
BACKGROUND: The availability and quality of irrigation water have become a serious concern because of global climate change and an increased competition for water by industry, domestic users and the environment. Therefore, exploring environmentally friendly water-saving irrigation strategies is essential for achieving food and environmental security. In northern Ethiopia, where traditional furrow irrigation is widely practiced, water mismanagement and its undesirable environmental impact are rampant. A 2-year field study was undertaken to compare the traditional irrigation management with surge and deficit irrigation practices on a Vertisol plot. RESULT: Results have shown that surge and deficit irrigation practices increase water productivity by 62% and 58%, respectively, when compared to traditional management. The study also found out that these practices reduce the adverse environmental impacts (waterlogging and salinity) of traditional management by minimizing deep percolation and tail water losses. Total irrigation depth was reduced by 12% (for surge) and 27% (for deficit) when compared to traditional management. CONCLUSION: Based on the results, the study concluded that surge and deficit irrigation technologies not only improve water productivity but also enhance environmental sustainability.
