The Pearl River Delta （PRD） is one of the most developed and densely populated regions in China.Quantifying the amount of pathogens in the source of drinking water is important for improving water quality.We collect...The Pearl River Delta （PRD） is one of the most developed and densely populated regions in China.Quantifying the amount of pathogens in the source of drinking water is important for improving water quality.We collected water samples from six major water storage reservoirs in the PRD region in both wet and dry seasons in 2006.Results showed that external environmental factors,such as precipitation,location,as well as the internal environmental factors,i.e.,physicochemical properties of the water,were closely related with the distribution of coliforms.Seasonally,the coliform bacterial concentrations in wet season were one to two orders of magnitude greater than those in dry season.Spatially,coliform bacterial levels in reservoirs near urban and industrial areas were significantly higher （p 〈 0.05） than those in remote areas.Correlation analyses showed that the levels of coliforms had close relationships with pH,temperature,suspended solid,organic and inorganic nutrients in water.Principal components analysis further demonstrated that total coliforms in the reservoirs were closely related with water physicochemical properties,while fecal coliforms were more associated with external input brought in by seasonal runoff.展开更多
Six common algal fatty acids （FAs） with different numbers of double bonds, lipophilic fractions and proteins extracted from the diatom Navicula pelliculosa and algal ceils were chlorinated to evaluate their potentia...Six common algal fatty acids （FAs） with different numbers of double bonds, lipophilic fractions and proteins extracted from the diatom Navicula pelliculosa and algal ceils were chlorinated to evaluate their potential in generating disinfection by-products （DBPs）. The result showed that the more double bonds in the FAs, the higher the amounts of chloroform and dichloroacetic acid （DCAA） produced, but such a pattern was not observed for trichloroacetic acid （TCAA）. Based on the previously reported composition of fatty acids in algal lipids, the DBP generation potentials of algal lipids were calculated. These predicted values were much lower than those measured in the chlorinated algal lipophilic fraction, suggesting unknown lipophilic fraction（s） served as potent DBPs precursors. Another calculation attempted to predict DBP production in algal cells based on algal lipid and protein composition, given quantified measured DBP production per unit algal lipid and proteins. The analysis showed that the observed DBP production was similar to that predicted （〈 35% difference）, suggesting that algal biochemical compositions may serve as a bioindicator for preliminary estimation of chloroform, DCAA and TCAA formation upon chlorinating algae.展开更多
基金supported by the Scientific Research Foundation for the Doctor of Zhejiang Normal University (No. ZC304009166)
文摘The Pearl River Delta （PRD） is one of the most developed and densely populated regions in China.Quantifying the amount of pathogens in the source of drinking water is important for improving water quality.We collected water samples from six major water storage reservoirs in the PRD region in both wet and dry seasons in 2006.Results showed that external environmental factors,such as precipitation,location,as well as the internal environmental factors,i.e.,physicochemical properties of the water,were closely related with the distribution of coliforms.Seasonally,the coliform bacterial concentrations in wet season were one to two orders of magnitude greater than those in dry season.Spatially,coliform bacterial levels in reservoirs near urban and industrial areas were significantly higher （p 〈 0.05） than those in remote areas.Correlation analyses showed that the levels of coliforms had close relationships with pH,temperature,suspended solid,organic and inorganic nutrients in water.Principal components analysis further demonstrated that total coliforms in the reservoirs were closely related with water physicochemical properties,while fecal coliforms were more associated with external input brought in by seasonal runoff.
基金supported by the Faculty Research Grant(FRG1/08-09/056, FRG1/09-10/047, Faculty of Science of Hong Kong Baptist University) awarded to Y.Liang
文摘Six common algal fatty acids （FAs） with different numbers of double bonds, lipophilic fractions and proteins extracted from the diatom Navicula pelliculosa and algal ceils were chlorinated to evaluate their potential in generating disinfection by-products （DBPs）. The result showed that the more double bonds in the FAs, the higher the amounts of chloroform and dichloroacetic acid （DCAA） produced, but such a pattern was not observed for trichloroacetic acid （TCAA）. Based on the previously reported composition of fatty acids in algal lipids, the DBP generation potentials of algal lipids were calculated. These predicted values were much lower than those measured in the chlorinated algal lipophilic fraction, suggesting unknown lipophilic fraction（s） served as potent DBPs precursors. Another calculation attempted to predict DBP production in algal cells based on algal lipid and protein composition, given quantified measured DBP production per unit algal lipid and proteins. The analysis showed that the observed DBP production was similar to that predicted （〈 35% difference）, suggesting that algal biochemical compositions may serve as a bioindicator for preliminary estimation of chloroform, DCAA and TCAA formation upon chlorinating algae.
