The effectiveness of Elodea nuttallii combined with a mixture of hydrous ferric oxide,zeolite and calcite(HZC)to reduce the internal loading of phosphorus(P)from sediment and its mechanism were studied,and the effect ...The effectiveness of Elodea nuttallii combined with a mixture of hydrous ferric oxide,zeolite and calcite(HZC)to reduce the internal loading of phosphorus(P)from sediment and its mechanism were studied,and the effect of Elodea nuttallii combined with HZC on the composition and function of the microbial communities in the surface sediment was also investigated.The results showed that the combination utilization of Elodea nuttallii and HZC can decrease the risk of phosphorus liberation from sediment to the overlying water,and the controlling efficiency of Elodea nuttallii combined with HZCwas higher than that of Elodea nuttallii or HZC alone.The passivation of labile P measured by diffusive gradient in thin film device and mobile P played a crucial role in the control of internal P loading from sediment by the combined Elodea nuttallii+HZC treatment.HZC capping had a promoting effect on the growth of Elodea nuttallii.This was beneficial to the absorption of phosphorus from sediment by Elodea nuttallii.The combined application of Elodea nuttallii and HZC not only had a certain negative effect on the diversity of bacteria in the surface sediment,but also changed themicrobial compositions of the surface sediment at the levels of phylum and genus.However,the microbial communities in the surface sediment still can perform good ecological function.The above results suggest that the combined application of Elodea nuttallii and HZC has a high potential in the management of internal P loading from sediment.展开更多
In a microcosm system where Elodea nuttallii and Bisphenol A （BPA） coexist, with the help of Liquid chromatography-mass spectrometer （LC-MS） and gas chromatography-mass spectrometer （GC-MS）, the dynamics of phyt...In a microcosm system where Elodea nuttallii and Bisphenol A （BPA） coexist, with the help of Liquid chromatography-mass spectrometer （LC-MS） and gas chromatography-mass spectrometer （GC-MS）, the dynamics of phytodegradation of BPA with concentration 1-20 mg/L and the products of phytodegradation was studied. Antioxidation activity and phospholipids fatty acids were measured to evaluate the effects of BPA on E.nuttallii. The results showed that the half life period of phytodegradation of BPA was less than 15 days. 2-（4-hydroxypheny）-2-（3,4-o-dihydroxypheny） propane and 2, 2-bis（4-hydroxypheny） propyl alcohol were identified to be as two possible products of BPA. The peroxidase （POD） activity of E.nuttallii decreased by 50% to 100% compared with that controlled at the end of the experiment. The fatty acid methanol esters （FAMEs） changed obviously too. It showed that oxidation stress and membrane damage would be the two effcting aspects of BPA on E.nuttallii.展开更多
Aims both high and low densities of macrophyte vegetation can impair its ecosystem service function.Harvesting is often applied to macrophyte vegetation to maintain an appropriate density.Vegetation harvesting has occ...Aims both high and low densities of macrophyte vegetation can impair its ecosystem service function.Harvesting is often applied to macrophyte vegetation to maintain an appropriate density.Vegetation harvesting has occasionally gone awry and caused catastrophes,such as vegetation disappearance and cyanobacterial dominance in waterways and lakes.because water depth influences macrophyte density at all life stages,the simultaneous influences of harvesting and water depth should be carefully examined.Thus,this study aims to quantify the effects of differently harvesting Elodea nuttal-lii on its growth and reproduction at different water depths in field experiments.Methods Four harvest intensities(harvesting E.nuttallii plant heights equal to 25%,50%,75%and 100%of the water depth)were applied to E.nuttallii growing at four different water depths(60,90,120 and 150 cm).Plant length and root length were measured.The node number,root number of each plant and number of floating plants were counted before harvesting.The harvested plant were dried to a constant weight for dry weight determination.Important Findings The rate of increase in the length and shoot number of E.nuttallii varied from−0.012 to 0.440 day^(−1) and from−0.020 to 0.639 day^(−1),respec-tively.Water depth>150 cm would limit E.nuttallii growth.Elodea nuttallii responded to increasing water depths and low-intensity har-vesting by increasing internodal length and decreasing shoot number.The larger internodal length of E.nuttallii observed in relatively deeper water was also induced by the physical strain generated by its buoy-ancy as its specific gravity was less than water’s.The physical mecha-nism of removing the plant canopy by harvesting decreased E.nuttallii buoyancy and prevented floating.Harvesting increased plant produc-tion in shallow waters<90 cm deep.moreover,it is also necessary to perform three medium-intensity harvests at a water depth of 120 cm and one low-intensity harvest or no harvesting at a water depth of 150 cm to achieve longer lifetimes and less biomass near the water surface when the plants reach or approach the water surface.展开更多
基金supported by the Capacity Building Project of Local University of Shanghai Municipal Science and Technology Commission(No.10230502900)the Program for Shanghai Collaborative Innovation Center for Cultivating Elite Breeds and Green-culture of Aquaculture animals(No.2021-KJ-02-12)the Innovation Project for Chongming Agriculture Industry from Chongming District Agriculture Commission of Shanghai(No.2022CNKC-01-05).
文摘The effectiveness of Elodea nuttallii combined with a mixture of hydrous ferric oxide,zeolite and calcite(HZC)to reduce the internal loading of phosphorus(P)from sediment and its mechanism were studied,and the effect of Elodea nuttallii combined with HZC on the composition and function of the microbial communities in the surface sediment was also investigated.The results showed that the combination utilization of Elodea nuttallii and HZC can decrease the risk of phosphorus liberation from sediment to the overlying water,and the controlling efficiency of Elodea nuttallii combined with HZCwas higher than that of Elodea nuttallii or HZC alone.The passivation of labile P measured by diffusive gradient in thin film device and mobile P played a crucial role in the control of internal P loading from sediment by the combined Elodea nuttallii+HZC treatment.HZC capping had a promoting effect on the growth of Elodea nuttallii.This was beneficial to the absorption of phosphorus from sediment by Elodea nuttallii.The combined application of Elodea nuttallii and HZC not only had a certain negative effect on the diversity of bacteria in the surface sediment,but also changed themicrobial compositions of the surface sediment at the levels of phylum and genus.However,the microbial communities in the surface sediment still can perform good ecological function.The above results suggest that the combined application of Elodea nuttallii and HZC has a high potential in the management of internal P loading from sediment.
基金Supported by the National High Technology Research and Development Program of China (863 Program) (2002AA601021)the National Basic Research Program of China (973 Program) (2002CB412309)+1 种基金the Na-tional Science Foundation for Distinguished Youth Scholar (39925007)the National Natural Science Foundation of China (30123004)
文摘In a microcosm system where Elodea nuttallii and Bisphenol A （BPA） coexist, with the help of Liquid chromatography-mass spectrometer （LC-MS） and gas chromatography-mass spectrometer （GC-MS）, the dynamics of phytodegradation of BPA with concentration 1-20 mg/L and the products of phytodegradation was studied. Antioxidation activity and phospholipids fatty acids were measured to evaluate the effects of BPA on E.nuttallii. The results showed that the half life period of phytodegradation of BPA was less than 15 days. 2-（4-hydroxypheny）-2-（3,4-o-dihydroxypheny） propane and 2, 2-bis（4-hydroxypheny） propyl alcohol were identified to be as two possible products of BPA. The peroxidase （POD） activity of E.nuttallii decreased by 50% to 100% compared with that controlled at the end of the experiment. The fatty acid methanol esters （FAMEs） changed obviously too. It showed that oxidation stress and membrane damage would be the two effcting aspects of BPA on E.nuttallii.
基金the Natural Science Foundation of China(NSFC41230853)the China National Fund for Water Pollution Control and Management Project(2014ZX07101-011)the Key Deployment Project of Chinese Academy of Sciences(KZZD-EW-10).
文摘Aims both high and low densities of macrophyte vegetation can impair its ecosystem service function.Harvesting is often applied to macrophyte vegetation to maintain an appropriate density.Vegetation harvesting has occasionally gone awry and caused catastrophes,such as vegetation disappearance and cyanobacterial dominance in waterways and lakes.because water depth influences macrophyte density at all life stages,the simultaneous influences of harvesting and water depth should be carefully examined.Thus,this study aims to quantify the effects of differently harvesting Elodea nuttal-lii on its growth and reproduction at different water depths in field experiments.Methods Four harvest intensities(harvesting E.nuttallii plant heights equal to 25%,50%,75%and 100%of the water depth)were applied to E.nuttallii growing at four different water depths(60,90,120 and 150 cm).Plant length and root length were measured.The node number,root number of each plant and number of floating plants were counted before harvesting.The harvested plant were dried to a constant weight for dry weight determination.Important Findings The rate of increase in the length and shoot number of E.nuttallii varied from−0.012 to 0.440 day^(−1) and from−0.020 to 0.639 day^(−1),respec-tively.Water depth>150 cm would limit E.nuttallii growth.Elodea nuttallii responded to increasing water depths and low-intensity har-vesting by increasing internodal length and decreasing shoot number.The larger internodal length of E.nuttallii observed in relatively deeper water was also induced by the physical strain generated by its buoy-ancy as its specific gravity was less than water’s.The physical mecha-nism of removing the plant canopy by harvesting decreased E.nuttallii buoyancy and prevented floating.Harvesting increased plant produc-tion in shallow waters<90 cm deep.moreover,it is also necessary to perform three medium-intensity harvests at a water depth of 120 cm and one low-intensity harvest or no harvesting at a water depth of 150 cm to achieve longer lifetimes and less biomass near the water surface when the plants reach or approach the water surface.
