It is important to select suitable organisms to adapt the requirement of different environment monitoring purposes.Following our previous study,the behavioral responses of Daphnia magna and Japanese madaka （Oryzias l...It is important to select suitable organisms to adapt the requirement of different environment monitoring purposes.Following our previous study,the behavioral responses of Daphnia magna and Japanese madaka （Oryzias latipes） were investigated and compared under flow-through conditions in an on-line biomonitoring system.The results showed that both D.magna and Japanese madaka had similar biological clock,but the circadian rhythms of Japanese madaka was more clearly recorded than that of D.magna.And the sensitivity of D.magna was about two orders of magnitudes higher than that of Japanese madaka in different types of toxic chemicals （dichlorovos,deltamethrin and cadmium chloride）.However,when both animals were used in an on-line biomonitoring system,the life span of D.magna was less than 7 days and Japanese madaka could last for more than one month without feeding.Therefore,D.magna was proposed to be a more sensitive bioindicator and was suitable for short term monitoring the pollution events at concentration level closing to the water quality standard,while Japanese madaka was more suitable for the long-term monitoring for accidental discharges.展开更多
The potential effects of nanoscale CuO（nCuO）,nanoscale ZnO（nZnO） and their mixtures on Daphnia magna were investigated,including 48-h acute toxicity and 21-d chronic toxicity tests as well as a feeding experiment....The potential effects of nanoscale CuO（nCuO）,nanoscale ZnO（nZnO） and their mixtures on Daphnia magna were investigated,including 48-h acute toxicity and 21-d chronic toxicity tests as well as a feeding experiment.The results of acute toxicity show that nCuO/nZnO mixture was the most toxic followed by nCuO and nZnO.The nanoparticles（NPs） inhibited both the growth and reproduction of Daphnia magna during the testing period.Concentration dependence was apparent in all the cases and the intrinsic rate of natural increase was confirmed to be a very sensitive parameter to NPs exposure.Binary mixture appeared to be more toxic than the corresponding individual exposures at most cases except for the feeding behavior.展开更多
Cyanobacterial blooms in eutrophic freshwater systems are a worldwide problem, creating adverse effects for many aquatic organisms by producing toxic mierocystins and deteriorating water quality. In this study, microc...Cyanobacterial blooms in eutrophic freshwater systems are a worldwide problem, creating adverse effects for many aquatic organisms by producing toxic mierocystins and deteriorating water quality. In this study, microcystins （MCs） in Microcystis aeruginosa, and Daphnia magna exposed to M. aeruginosa, were analyzed by HPLC-MS, and the effects of M. aeruginosa on D. magna were investigated. When D. magna was exposed to M. aeruginosa for more than 2 h, Microcystin-LR （MC-LR） was detected. When exposed to 1.5× 10^6, 3× 10^6, 0.75× 10^7, and 1.5× 10^7 cell/mL of M. aeruginosa for 96 h, average survival of D. magna for treatments were 23.33%, 33.33%, 13.33%, 16.67%, respectively, which were significantly lower than the average 100% survival in the control group （P 〈 0.05）. The adverse effects ofM. aeruginosa on body length, time for the first brood, brood numbers, gross fecundity, lifespan, and population growth olD. magna were density-dependent. These results suggest that the occurrence of M. aeruginosa blooms could strongly inhibit the population growth of D. magna through depression of survival, individual growth and gross fecundity. In the most serious situations, M. aeruginosa blooms could undermine the food web by eliminating filter-feeding zooplankton, which would destroy the ecological balance of aquaculture water bodies.展开更多
The acute and chronic toxic effects of bifenthrin on Daphnia magna were studied. The results showed that 24 h-EC 50 , 48 h-LC 50 and 96 h-LC 50 of bifenthrin on D. magna were 3.24, 12.40 and 1.40 μg/L r...The acute and chronic toxic effects of bifenthrin on Daphnia magna were studied. The results showed that 24 h-EC 50 , 48 h-LC 50 and 96 h-LC 50 of bifenthrin on D. magna were 3.24, 12.40 and 1.40 μg/L respectively. And the LOEC and NOEC of bifenthrin were 0.02 and 0.004 μg/L respectively. The recovery test of bifenthrin on Daphnia magna was presented. Daphnia magna(F 0 generation) were exposed during 21 d to different bifenthrin concentrations. Offspring(animals from the first and third brood: F 1(1st) and F 1(3rd), respectively) were transferred to a free pesticide medium during a 21 d recovery period. In this recovery study, survival, growth, reproduction(mean total young per female, onset of reproduction and number broods per female) and the intrinsic rate of natural increase (r) were assessed as parameters. Reproduction such as number of young per female as well as length was still reduced in F 1(1st) generation daphnids from parentals(F 0) exposed to the bifenthrin. However F 1(3rd) individuals from parentals exposed to pesticide concentrations were able to restore reproduction when a recovery period of 21 d was allowed, but the length of F 1(3rd) from parentals exposed to the 0.5 and 0.75 μg/L bifenthrin concentration was still significantly effected(P<0.05).展开更多
In order to study toxicological effects of perfluorononanoic acid （PFNA）, perfluorooctane sulfonate （PFOS）, and their mixtures （PFNA/ PFOS） on Daphnia magna （D. magna）, a suite of comprehensive toxicity tests ...In order to study toxicological effects of perfluorononanoic acid （PFNA）, perfluorooctane sulfonate （PFOS）, and their mixtures （PFNA/ PFOS） on Daphnia magna （D. magna）, a suite of comprehensive toxicity tests were conducted, including a 48-h acute toxicity test, a 21-day chronic test, a feeding experiment, and a biomarker assay. D. magna were exposed to aqueous solutions of PFNA and PFOS （alone and in combination） at concentrations ranging from 0.008 to 5 mg/L. The survival, growth, and reproduction of D. magna were monitored over a 21- day life cycle. The biomarkers, including acetylcholinesterase （ACHE）, superoxide dismutase （SOD）, and catalase （CAT） activities, were determined after seven days of exposure. PFOS was more toxic than PFNA based on the results of the acute toxicity test. Perfluorinated compounds （PFCs） inhibited both growth and reproduction of D. magna during the testing period. The ingestion rates and the biomarkers, including ACHE, SOD, and CAT activities, were significantly inhibited by PFCs in most cases. Moreover, the combined effects related to the growth and reproduction showed the antagonistic effects of PFCs.展开更多
基金supported by the National Key Program for Water Pollution Control (No. 2009ZX07210-009,2009ZX07209-005,2009ZX07527-002)the State Key Laboratory of Environmental Aquatic Chemistry (No.08K07ESPCR)
文摘It is important to select suitable organisms to adapt the requirement of different environment monitoring purposes.Following our previous study,the behavioral responses of Daphnia magna and Japanese madaka （Oryzias latipes） were investigated and compared under flow-through conditions in an on-line biomonitoring system.The results showed that both D.magna and Japanese madaka had similar biological clock,but the circadian rhythms of Japanese madaka was more clearly recorded than that of D.magna.And the sensitivity of D.magna was about two orders of magnitudes higher than that of Japanese madaka in different types of toxic chemicals （dichlorovos,deltamethrin and cadmium chloride）.However,when both animals were used in an on-line biomonitoring system,the life span of D.magna was less than 7 days and Japanese madaka could last for more than one month without feeding.Therefore,D.magna was proposed to be a more sensitive bioindicator and was suitable for short term monitoring the pollution events at concentration level closing to the water quality standard,while Japanese madaka was more suitable for the long-term monitoring for accidental discharges.
基金Supported by the National Basic Research Program of China(No.2010CB429006)the Fundamental Research Funds for the Central Universities of China(No.2010B05714)
文摘The potential effects of nanoscale CuO（nCuO）,nanoscale ZnO（nZnO） and their mixtures on Daphnia magna were investigated,including 48-h acute toxicity and 21-d chronic toxicity tests as well as a feeding experiment.The results of acute toxicity show that nCuO/nZnO mixture was the most toxic followed by nCuO and nZnO.The nanoparticles（NPs） inhibited both the growth and reproduction of Daphnia magna during the testing period.Concentration dependence was apparent in all the cases and the intrinsic rate of natural increase was confirmed to be a very sensitive parameter to NPs exposure.Binary mixture appeared to be more toxic than the corresponding individual exposures at most cases except for the feeding behavior.
基金Supported by the Aquaculture and Fisheries Collaborative Research Support Program of USAID (No. 1366)the Shanghai Rising-Star Program (No. 08QA1405900)+1 种基金the Innovation Program of Shanghai Municipal Education Commission (No. 09YZ277)the Shanghai Leading Academic Discipline Project (No. Y1101)
文摘Cyanobacterial blooms in eutrophic freshwater systems are a worldwide problem, creating adverse effects for many aquatic organisms by producing toxic mierocystins and deteriorating water quality. In this study, microcystins （MCs） in Microcystis aeruginosa, and Daphnia magna exposed to M. aeruginosa, were analyzed by HPLC-MS, and the effects of M. aeruginosa on D. magna were investigated. When D. magna was exposed to M. aeruginosa for more than 2 h, Microcystin-LR （MC-LR） was detected. When exposed to 1.5× 10^6, 3× 10^6, 0.75× 10^7, and 1.5× 10^7 cell/mL of M. aeruginosa for 96 h, average survival of D. magna for treatments were 23.33%, 33.33%, 13.33%, 16.67%, respectively, which were significantly lower than the average 100% survival in the control group （P 〈 0.05）. The adverse effects ofM. aeruginosa on body length, time for the first brood, brood numbers, gross fecundity, lifespan, and population growth olD. magna were density-dependent. These results suggest that the occurrence of M. aeruginosa blooms could strongly inhibit the population growth of D. magna through depression of survival, individual growth and gross fecundity. In the most serious situations, M. aeruginosa blooms could undermine the food web by eliminating filter-feeding zooplankton, which would destroy the ecological balance of aquaculture water bodies.
文摘The acute and chronic toxic effects of bifenthrin on Daphnia magna were studied. The results showed that 24 h-EC 50 , 48 h-LC 50 and 96 h-LC 50 of bifenthrin on D. magna were 3.24, 12.40 and 1.40 μg/L respectively. And the LOEC and NOEC of bifenthrin were 0.02 and 0.004 μg/L respectively. The recovery test of bifenthrin on Daphnia magna was presented. Daphnia magna(F 0 generation) were exposed during 21 d to different bifenthrin concentrations. Offspring(animals from the first and third brood: F 1(1st) and F 1(3rd), respectively) were transferred to a free pesticide medium during a 21 d recovery period. In this recovery study, survival, growth, reproduction(mean total young per female, onset of reproduction and number broods per female) and the intrinsic rate of natural increase (r) were assessed as parameters. Reproduction such as number of young per female as well as length was still reduced in F 1(1st) generation daphnids from parentals(F 0) exposed to the bifenthrin. However F 1(3rd) individuals from parentals exposed to pesticide concentrations were able to restore reproduction when a recovery period of 21 d was allowed, but the length of F 1(3rd) from parentals exposed to the 0.5 and 0.75 μg/L bifenthrin concentration was still significantly effected(P<0.05).
基金supported by the National Natural Science Foundation of China(Grant No.51279061)the Qing Lan Project of Jiangsu Province
文摘In order to study toxicological effects of perfluorononanoic acid （PFNA）, perfluorooctane sulfonate （PFOS）, and their mixtures （PFNA/ PFOS） on Daphnia magna （D. magna）, a suite of comprehensive toxicity tests were conducted, including a 48-h acute toxicity test, a 21-day chronic test, a feeding experiment, and a biomarker assay. D. magna were exposed to aqueous solutions of PFNA and PFOS （alone and in combination） at concentrations ranging from 0.008 to 5 mg/L. The survival, growth, and reproduction of D. magna were monitored over a 21- day life cycle. The biomarkers, including acetylcholinesterase （ACHE）, superoxide dismutase （SOD）, and catalase （CAT） activities, were determined after seven days of exposure. PFOS was more toxic than PFNA based on the results of the acute toxicity test. Perfluorinated compounds （PFCs） inhibited both growth and reproduction of D. magna during the testing period. The ingestion rates and the biomarkers, including ACHE, SOD, and CAT activities, were significantly inhibited by PFCs in most cases. Moreover, the combined effects related to the growth and reproduction showed the antagonistic effects of PFCs.
