High-density aquaculture often causes the emission of polluted water to the marine environment in the coastal areas of China.To solve the aquaculture-related water quality problems,it is appropriate to adapt eco-frien...High-density aquaculture often causes the emission of polluted water to the marine environment in the coastal areas of China.To solve the aquaculture-related water quality problems,it is appropriate to adapt eco-friendly methods,such as using microbes and their metabolic products to purify polluted water.In this study,the purifying effects ofBacillus amyloliquefaciens(IAE635)metabolites(poly-γ-glutamic acid;PP)and IAE635 combined with their metabolites(MP)on turbidity,COD,NO3--N,NH4+-N,Vibrio spp.andcoliform bacteria in coastal aquaculture wastewater were conducted in the lab and in situ ponds.The results showed that the removal ofturbidity,COD,NH4+-Nand NO3--Nwith PP and MP was more significant(p<0.05).Compared to Control treatment(Co),the turbidity,COD,NH4+-Nand NO3--N concentrations at 24thhour were evidently reduced by 86.6%,87.5%,83.3%and 58.0%for PP,87.9%,93.5%,86.5%and 78.0%for MP,respectively.The populations of water pathogens under PP and MP were also significantly(p<0.05)removed compared with those of Co;at 24thhour,the Vibriospp.and coliform bacteria were decreased by 68.7%and 66.3%forPP,75.0%and 67.1%for MP,respectively.The water purifying effect of MP was slightly better than that of PP.In situ pond purification test demonstrated that MP significantly lowered the concentrations of turbidity,COD,NH4+-N,NO3--N and NO2--N,which was more effective than EM.A significantly higher(p<0.05)γ-PGA concentration and the total bacterial population for MP compared to PP indicatedthatMPpurifies the coastal aquaculture wastewaterby both flocculation and microbial decomposition.The application of MP will benefit the aquaculture industry by providing a novel method for the removal of chemical pollutants and pathogens.展开更多
Establishing strategies of organic amendments application to mitigate the adverse effects of saline irrigation are essential for the sustainable agriculture.A two-year pot experiment was conducted using combinations o...Establishing strategies of organic amendments application to mitigate the adverse effects of saline irrigation are essential for the sustainable agriculture.A two-year pot experiment was conducted using combinations of organic amendments including effective microorganisms(EM),biochar(BC)and digestate(Di)to investigate their effects on soil and melon(Cucumis melo L.)compared with the recommended NPK fertilizer and Control(CK)under two levels of irrigation water salinity(SL0:0.25 dS/m,SL1:2.0 dS/m).Results showed combined applications of organic amendments could significantly(p<0.05)increase soil pH and organic matter(OM)compared to NPK and CK.Application of organic amendments containing BC evidently increased the sodium adsorptive capacity(SAC)under saline water solution.The combined application of EM,BC and Di(EM+BC+Di)could significantly(p<0.05)improve soil available water retention under SL0 and SL1 compared with other treatments.Results also showed organic amendments application can significantly(p<0.05)enhance the photosynthetic rate(Pr)and reduce sodium ion(Na+)content in melon leaves.EM+BC+Di could significantly(p<0.05)increase water use efficiency(WUE)and fruit yield of melon under SL0 and SL1 in comparison to other treatments.It proved that EM+BC+Di had a positive effect on soil improvement,melon growth,WUE and fruit yield.Moreover,EM+BC+Di could be used as an alternative strategy for mineral NPK fertilization of melon at reasonable dosages and frequencies under saline irrigation.展开更多
基金This work was financially supported by the Major Science and Technology Program for Water Pollution Control and Treatment of China(Grant No.2017ZX07108-001)the Fundamental Research Funds for the Central Universities(Grant No.2019B18314)+2 种基金the Jiangsu Scientific Research Program(Grant No.BE2017765)This work was also supported by a grant from the Science and Technology Project for Nanjing Water Conservancy Bureau(2019-208-6)China Scholarship Council(CSC).
文摘High-density aquaculture often causes the emission of polluted water to the marine environment in the coastal areas of China.To solve the aquaculture-related water quality problems,it is appropriate to adapt eco-friendly methods,such as using microbes and their metabolic products to purify polluted water.In this study,the purifying effects ofBacillus amyloliquefaciens(IAE635)metabolites(poly-γ-glutamic acid;PP)and IAE635 combined with their metabolites(MP)on turbidity,COD,NO3--N,NH4+-N,Vibrio spp.andcoliform bacteria in coastal aquaculture wastewater were conducted in the lab and in situ ponds.The results showed that the removal ofturbidity,COD,NH4+-Nand NO3--Nwith PP and MP was more significant(p<0.05).Compared to Control treatment(Co),the turbidity,COD,NH4+-Nand NO3--N concentrations at 24thhour were evidently reduced by 86.6%,87.5%,83.3%and 58.0%for PP,87.9%,93.5%,86.5%and 78.0%for MP,respectively.The populations of water pathogens under PP and MP were also significantly(p<0.05)removed compared with those of Co;at 24thhour,the Vibriospp.and coliform bacteria were decreased by 68.7%and 66.3%forPP,75.0%and 67.1%for MP,respectively.The water purifying effect of MP was slightly better than that of PP.In situ pond purification test demonstrated that MP significantly lowered the concentrations of turbidity,COD,NH4+-N,NO3--N and NO2--N,which was more effective than EM.A significantly higher(p<0.05)γ-PGA concentration and the total bacterial population for MP compared to PP indicatedthatMPpurifies the coastal aquaculture wastewaterby both flocculation and microbial decomposition.The application of MP will benefit the aquaculture industry by providing a novel method for the removal of chemical pollutants and pathogens.
基金by the National Nature Science Foundation of China(51779182)the Fundamental Research Funds for the Central Universities(2017B20414)+1 种基金the National Key Research and Development Program(2020YFD0900705)the Science and Technology Project for Nanjing Water Conservancy Bureau(2019-208-6).
文摘Establishing strategies of organic amendments application to mitigate the adverse effects of saline irrigation are essential for the sustainable agriculture.A two-year pot experiment was conducted using combinations of organic amendments including effective microorganisms(EM),biochar(BC)and digestate(Di)to investigate their effects on soil and melon(Cucumis melo L.)compared with the recommended NPK fertilizer and Control(CK)under two levels of irrigation water salinity(SL0:0.25 dS/m,SL1:2.0 dS/m).Results showed combined applications of organic amendments could significantly(p<0.05)increase soil pH and organic matter(OM)compared to NPK and CK.Application of organic amendments containing BC evidently increased the sodium adsorptive capacity(SAC)under saline water solution.The combined application of EM,BC and Di(EM+BC+Di)could significantly(p<0.05)improve soil available water retention under SL0 and SL1 compared with other treatments.Results also showed organic amendments application can significantly(p<0.05)enhance the photosynthetic rate(Pr)and reduce sodium ion(Na+)content in melon leaves.EM+BC+Di could significantly(p<0.05)increase water use efficiency(WUE)and fruit yield of melon under SL0 and SL1 in comparison to other treatments.It proved that EM+BC+Di had a positive effect on soil improvement,melon growth,WUE and fruit yield.Moreover,EM+BC+Di could be used as an alternative strategy for mineral NPK fertilization of melon at reasonable dosages and frequencies under saline irrigation.
