It is important to assess the effect on zooplankton when perform the environmental protection or restoration technology, especially removing algal blooms, because algae were the major primary producer in algal lakes. ...It is important to assess the effect on zooplankton when perform the environmental protection or restoration technology, especially removing algal blooms, because algae were the major primary producer in algal lakes. The influence on zooplankton community after half a year of algal blooms removed by chitosan-modified soils in Taihu Lake was assessed and the rationality of carrying out the process semiannually was evaluated in the present study. Morphological composition and genetic diversity of zooplankton community were investigated by microscope checkup and polymerase chain reaction-denatured gradient gel electrophoresis （PCR-DGGE）. A total of 44 zooplankton taxa （23 protozoa, 17 rotifers, 3 copepoda and 1 cladocera） were detected by microscope checkup, and a total of 91 bands （28 bands amplified by primers F1427-GC and R1616, 63 bands amplified by primers Fung-GC and NS1） were detected by PCR-DGGE. The results of cluster analysis or detrended correspondence analysis indicated that there was no considerable difference in morphological composition of zooplankton and DGGE profiles between experimental and control sites, and DGGE profiles could represent the biologic diversity. The study showed that zooplankton community could recover original condition after half year of algal blooms removed by chitosan-modified soils and it was acceptable to apply this process semiannually. In addition, the results revealed that PCR-DCJGE could be applied to investigate the impacts of the environmental protection or restoration engineering on zooplankton community diversity.展开更多
Urban lake ecosystems are significant for social development,but currently we know little about the geographical distribution of algal community in urban lakes at a large-scale.In this study,we investigated the algal ...Urban lake ecosystems are significant for social development,but currently we know little about the geographical distribution of algal community in urban lakes at a large-scale.In this study,we investigated the algal community structure in different areas of urban lakes in China and evaluated the influence of water quality parameters and geographical location on the algal community.The results showed that obvious differences in water quality and algal communities were observed among urban lakes in different geographical areas.Chlorophyta was the dominant phylum,followed by cyanobacteria in all areas.The network analysis indicated that algal community composition in urban lakes of the western and southern area showed more variations than the eastern and northern areas,respectively.Redundancy analysis and structural equation model revealed that nutrients and p H were dominant environmental factors that affected the algal community,and they showed higher influence than that of iron,manganese and COD Mn concentration.Importantly,algal community and density exhibited longitude and latitude relationship.In general,these results provided an ecological insight into large-scale geographical distributions of algal community in urban lakes,thereby having potential applications for management of the lakes.展开更多
Filamentous algae blooms(FABs)have been increasing globally in recent years,and their presence can have both harmful and beneficial effects on aquatic ecosystems.As one of the most common FABs,Cladophora blooms have b...Filamentous algae blooms(FABs)have been increasing globally in recent years,and their presence can have both harmful and beneficial effects on aquatic ecosystems.As one of the most common FABs,Cladophora blooms have been reported in the lakes of the Qinghai-Tibet Plateau during the past few years.However,there have been few studies focused on how FABs impact other aquatic organisms,especially in alpine lakes since these are at the forefront of responding to global climate change.In this study,the phytoplankton communities in different regions of Qinghai Lake were profiled in different seasons using meta-barcode sequencing.The phytoplankton assemblages in areas with Cladophora blooms were compared to those without Cladophora.The phytoplankton community structure correlated with physicochemical properties including water temperature,electrical conductivity,nitrate,and the presence or absence of Cladophora blooms.The relative abundance of Bacillariophytes was found to be higher in zones with Cladophora blooms than in other regions.Significant seasonal changes in phytoplankton biomass andβdiversity were observed in zones with Cladophora blooms.Growth and microbial degradation of Cladophora can change the pH,dissolved oxygen,secchi depth,and nitrate.Together with seasonal temperature and electrical conductivity changes,Cladophora growth can significantly impact the phytoplankton biomass,community dissimilarity and assembly process.These results showed that Cladophora plays a key role in littoral aquatic ecosystem ecology.展开更多
Modified biochar with higher electron transport and adsorption capabilities could significantly improve the performance of anaerobic ammonia oxidation(anammox).However,there are few related investigations on the reinf...Modified biochar with higher electron transport and adsorption capabilities could significantly improve the performance of anaerobic ammonia oxidation(anammox).However,there are few related investigations on the reinforcement of anammox through iron-modified Enteromorpha prolifera biochar(IMEPB).In this study,with the addition of the IMEPB in the anammox system,the enhancing process of anammox performance was studied,the improving feasibility of anammox was evaluated,and the reinforcing mechanism of anammox was elucidated.The results showed that the optimal iron−charcoal ratio(Fe:C)and IMEPB dosage were 1:10 and 10 g L^(−1),respectively.Under the optimal conditions,when the nitrogen loading rate gradually increased to 0.557(kg m^(−3) day^(−1)),the nitrogen removal efficiency and nitrogen removal rate of the anammox process supplemented with IMEPB increased by 11%,and the specific anammox activity increased by 23.8%.Compared with the control,the secretion of extracellular polymeric substances(EPS)of anammox bacteria supplemented IMEPB increased by 24.4%,greatly improving the stability of the anammox system.Meanwhile,EPS secretion further promoted the microbial activity of anammox bacteria,achieving a 19%increase in the abundance of Candidatus Brocadia.These findings demonstrate the potential mechanism of IMEPB in improving anammox,provide new insights into recycling E.prolifera,and provide a novel reinforcement strategy for anammox.In the future,adding IMEPB may be a vital measure for the practical application of anammox in coastal areas.展开更多
Urban lakes were critical in aquatic ecology environments,but how environmental factors affected the distribution and change characteristics of algal communities in urban lakes of Xi’an city was not clearly.Here,we i...Urban lakes were critical in aquatic ecology environments,but how environmental factors affected the distribution and change characteristics of algal communities in urban lakes of Xi’an city was not clearly.Here,we investigated the algal community structure of six urban lakes in Xi’an and evaluated the effects of water quality parameters on algae.The results indicated that the significant differences on physicochemical parameters existed in different urban lakes.The maximum concentration of total phosphorus in urban lakes was(0.18±0.01)mg/L and there was a phenomenon of phosphorus limitation.In addition,51 genera of algae were identified and Chlorella sp.was the dominant algal species,which was affiliated with Chlorophyta.Network analysis elucidated that each lake had a unique algal community network and the positive correlation was dominant in the interaction between algae species,illustrating that mature microbial communities existed or occupied similar niches.Redundancy analysis illustrated that environmental factors explained 47.35% variance of algal species-water quality correlation collectively,indicating that water quality conditions had a significant influence on the temporal variations of algae.Structural equation model further verified that algal community structure was directly or indirectly regulated by different water quality conditions.Our study shows that temporal patterns of algal communities can reveal the dynamics and interactions of different urban ecosystem types,providing a theoretical basis for assessing eutrophication levels and for water quality management.展开更多
基金supported by the Major State Basic Research Development Program of China(No. 2008CB418105)
文摘It is important to assess the effect on zooplankton when perform the environmental protection or restoration technology, especially removing algal blooms, because algae were the major primary producer in algal lakes. The influence on zooplankton community after half a year of algal blooms removed by chitosan-modified soils in Taihu Lake was assessed and the rationality of carrying out the process semiannually was evaluated in the present study. Morphological composition and genetic diversity of zooplankton community were investigated by microscope checkup and polymerase chain reaction-denatured gradient gel electrophoresis （PCR-DGGE）. A total of 44 zooplankton taxa （23 protozoa, 17 rotifers, 3 copepoda and 1 cladocera） were detected by microscope checkup, and a total of 91 bands （28 bands amplified by primers F1427-GC and R1616, 63 bands amplified by primers Fung-GC and NS1） were detected by PCR-DGGE. The results of cluster analysis or detrended correspondence analysis indicated that there was no considerable difference in morphological composition of zooplankton and DGGE profiles between experimental and control sites, and DGGE profiles could represent the biologic diversity. The study showed that zooplankton community could recover original condition after half year of algal blooms removed by chitosan-modified soils and it was acceptable to apply this process semiannually. In addition, the results revealed that PCR-DCJGE could be applied to investigate the impacts of the environmental protection or restoration engineering on zooplankton community diversity.
基金the National Natural Science Foundation of China(No.51978561)the International Science and Technology Cooperation Program in Shaanxi Province(No.2018kw-011)Shaanxi Provincial Key Research and Development Projects(Nos.2019ZDLSF06-01 and 2019ZDLSF06-02).
文摘Urban lake ecosystems are significant for social development,but currently we know little about the geographical distribution of algal community in urban lakes at a large-scale.In this study,we investigated the algal community structure in different areas of urban lakes in China and evaluated the influence of water quality parameters and geographical location on the algal community.The results showed that obvious differences in water quality and algal communities were observed among urban lakes in different geographical areas.Chlorophyta was the dominant phylum,followed by cyanobacteria in all areas.The network analysis indicated that algal community composition in urban lakes of the western and southern area showed more variations than the eastern and northern areas,respectively.Redundancy analysis and structural equation model revealed that nutrients and p H were dominant environmental factors that affected the algal community,and they showed higher influence than that of iron,manganese and COD Mn concentration.Importantly,algal community and density exhibited longitude and latitude relationship.In general,these results provided an ecological insight into large-scale geographical distributions of algal community in urban lakes,thereby having potential applications for management of the lakes.
基金the National Natural Science Foundation of China(U22A20454)the Second Tibetan Plateau Scientific Expedition and Research program(Grant No.2019QZKK0304).
文摘Filamentous algae blooms(FABs)have been increasing globally in recent years,and their presence can have both harmful and beneficial effects on aquatic ecosystems.As one of the most common FABs,Cladophora blooms have been reported in the lakes of the Qinghai-Tibet Plateau during the past few years.However,there have been few studies focused on how FABs impact other aquatic organisms,especially in alpine lakes since these are at the forefront of responding to global climate change.In this study,the phytoplankton communities in different regions of Qinghai Lake were profiled in different seasons using meta-barcode sequencing.The phytoplankton assemblages in areas with Cladophora blooms were compared to those without Cladophora.The phytoplankton community structure correlated with physicochemical properties including water temperature,electrical conductivity,nitrate,and the presence or absence of Cladophora blooms.The relative abundance of Bacillariophytes was found to be higher in zones with Cladophora blooms than in other regions.Significant seasonal changes in phytoplankton biomass andβdiversity were observed in zones with Cladophora blooms.Growth and microbial degradation of Cladophora can change the pH,dissolved oxygen,secchi depth,and nitrate.Together with seasonal temperature and electrical conductivity changes,Cladophora growth can significantly impact the phytoplankton biomass,community dissimilarity and assembly process.These results showed that Cladophora plays a key role in littoral aquatic ecosystem ecology.
基金National Natural Science Foundation of China(Grant Number 51978348).
文摘Modified biochar with higher electron transport and adsorption capabilities could significantly improve the performance of anaerobic ammonia oxidation(anammox).However,there are few related investigations on the reinforcement of anammox through iron-modified Enteromorpha prolifera biochar(IMEPB).In this study,with the addition of the IMEPB in the anammox system,the enhancing process of anammox performance was studied,the improving feasibility of anammox was evaluated,and the reinforcing mechanism of anammox was elucidated.The results showed that the optimal iron−charcoal ratio(Fe:C)and IMEPB dosage were 1:10 and 10 g L^(−1),respectively.Under the optimal conditions,when the nitrogen loading rate gradually increased to 0.557(kg m^(−3) day^(−1)),the nitrogen removal efficiency and nitrogen removal rate of the anammox process supplemented with IMEPB increased by 11%,and the specific anammox activity increased by 23.8%.Compared with the control,the secretion of extracellular polymeric substances(EPS)of anammox bacteria supplemented IMEPB increased by 24.4%,greatly improving the stability of the anammox system.Meanwhile,EPS secretion further promoted the microbial activity of anammox bacteria,achieving a 19%increase in the abundance of Candidatus Brocadia.These findings demonstrate the potential mechanism of IMEPB in improving anammox,provide new insights into recycling E.prolifera,and provide a novel reinforcement strategy for anammox.In the future,adding IMEPB may be a vital measure for the practical application of anammox in coastal areas.
基金supported by the National Science Foundation of China(Nos.51978561 and 51979217)the Youth Innovation Team of Shaanxi Universities in 2021(PI:Zhang Haihan)+1 种基金the Grant from Youth Innovation Team of Shaanxi Universities in 2021(No.21JP061)Natural Science Basic Research Program of Shaanxi Province(No.2022JM-224).
文摘Urban lakes were critical in aquatic ecology environments,but how environmental factors affected the distribution and change characteristics of algal communities in urban lakes of Xi’an city was not clearly.Here,we investigated the algal community structure of six urban lakes in Xi’an and evaluated the effects of water quality parameters on algae.The results indicated that the significant differences on physicochemical parameters existed in different urban lakes.The maximum concentration of total phosphorus in urban lakes was(0.18±0.01)mg/L and there was a phenomenon of phosphorus limitation.In addition,51 genera of algae were identified and Chlorella sp.was the dominant algal species,which was affiliated with Chlorophyta.Network analysis elucidated that each lake had a unique algal community network and the positive correlation was dominant in the interaction between algae species,illustrating that mature microbial communities existed or occupied similar niches.Redundancy analysis illustrated that environmental factors explained 47.35% variance of algal species-water quality correlation collectively,indicating that water quality conditions had a significant influence on the temporal variations of algae.Structural equation model further verified that algal community structure was directly or indirectly regulated by different water quality conditions.Our study shows that temporal patterns of algal communities can reveal the dynamics and interactions of different urban ecosystem types,providing a theoretical basis for assessing eutrophication levels and for water quality management.
