Filamentous green algae play an important functional role in element cycling and productivity in the diff erent water bodies. In hypersaline lakes and lagoons of the Crimea, filamentous green algae are present and for...Filamentous green algae play an important functional role in element cycling and productivity in the diff erent water bodies. In hypersaline lakes and lagoons of the Crimea, filamentous green algae are present and form bottom and floating mats that occupy large areas with high biomass, up to 4–5 kg(wet biomass)/m2. Cladophora spp. dominated in those mats. Five species of filamentous green algae(Chlorophyta) in Lake Chersonesskoye: C ladophora vadorum(Aresch.) Kütz., C. siwaschensis C. Meyer, C. echinus(Biasol.) Kütz., Ulothrix implexa(Kütz.) Kütz., Rhizoclonium tortuosum(Dillw.) Kütz., and seagrass(Angiospermae) R uppia cirrhosa(Petagna) Grande were found. Cladophora spp. and R. cirrhosa were found in the lake throughout the year, other types of algae were encountered episodically. In most cases the biomass of bottom mat exceeded that of the floating mat. In general, the total biomass of the bottom and floating mats in the lake areas at depths up to 30 cm was in a stable range of values from 100 to 290 mg(dry weight)/cm2. Animal and infusorian average abundance in mats reach high values: infusorians—up to 15 000 000 ind./m2, Cletocamptus retrogressus(Copepoda, Harpacticoida)—up to 730 000 ind./m2, Eucypris mareotica(Ostracoda)—up to 91 000 ind./m2 and Chironomidae larvae(Insecta, Diptera)—up to 140 ind./m2. Those values were much higher than in the plankton.展开更多
A pool of dormant stages of planktonic organisms in saline lakes is a substantial component in the plankton communities;we need to take it into account to understand plankton dynamics.Hypersaline water bodies in Crime...A pool of dormant stages of planktonic organisms in saline lakes is a substantial component in the plankton communities;we need to take it into account to understand plankton dynamics.Hypersaline water bodies in Crimea,the largest peninsula in the Black Sea,constitute a very characteristic and peculiar habitat type in the region.We examined the presence of crustacean resting stages in sediments of dried up sites of the Crimean hypersaline lakes.Sediment samples were taken in 9 different lakes.Experiments performed on the hatching of these resting stages showed the presence of Moina salina(Cladocera),parthenogenetic Artemia and Artemia urmiana(Anostraca),Eucypris mareotica( inflata)(Ostracoda),and Cletocamptus retrogressus(Harpacticoida).Comparing the experimental results obtained with clean dried brine shrimp cysts and those kept in sediment samples,it was noted that clean cysts hatched much faster than those from sediments did.Some components in bottom sediments slow down and desynchronize hatching from resting eggs in different groups of crustaceans.The sediments of different lakes inhibited the nauplii output from Artemia and ostracod resting eggs to different degrees.More data are needed before we can discuss the reasons of this inhibition.The nonsynchronous output of active stages from the bottom resting ones may be an adaptation that allows crustacean species to exist in extreme and unpredictably changing environments,avoiding the risk that all may emerge at once under unsuitable conditions.展开更多
Dissolved organic matter(DOM)plays a vital role in promoting carbon and nutrient cycling.It is a food source for organisms and controls the migration and transformation of trace metals and other contaminants in aquati...Dissolved organic matter(DOM)plays a vital role in promoting carbon and nutrient cycling.It is a food source for organisms and controls the migration and transformation of trace metals and other contaminants in aquatic systems.The contributions of aquatic DOM to the environment and ecology of a system are closely related to its abundance and chemical structure.In this study,the chemical composition and binding properties of DOM in a hypersaline lake watershed were investigated for the fi rst time using dissolved organic carbon(DOC)analysis,absorption spectroscopy,Fourier transform infrared spectroscopy,pyrolysis-GC-MS(Py-GC-MS),and fl uorescence parallel factor(PARAFAC)analysis combined with Pb(II)titration techniques.The results showed that DOM from the tributaries that fl owed into the lake had a lower DOC content,higher molecular weight,and higher specifi c UV absorbance than the DOM in lake water.Protein-like fl uorophores were mainly found in tributary and lake surface water DOM(LSDOM)and humic-like substances were abundant in lake groundwater DOM(LGDOM).Using this multi-methodological approach,we found that the DOM from the hypersaline lake watershed was mainly from microbial origins,and consisted of aromatics,carbohydrates,and aliphatics.The results from quantitative analysis showed that DOM from the infl owing tributaries contained more aromatics,lower carbohydrates,and lower aliphatics than DOM in the lake.Monocyclic aromatic hydrocarbons and carbohydrates were more abundant in LSDOM than LGDOM.The results from the Pb(II)titration technique coupled with PARAFAC analysis suggested that PARAFAC-derived components had relatively low condition stability constants(log K_(M)<2).Of the two types of lake DOM,the LGDOM had a higher Pb(II)binding potential than the LSDOM.From this study we have improved our understanding of how DOM within a hypersaline lake watershed varies in its composition and potential to bind with metals.展开更多
1 Introduction Copepods are a group of small crustaceans,which play an important ecological role in aquatic ecosystems.They occupy different ecological niches in aquatic food webs,contributes to biogenic element cycle...1 Introduction Copepods are a group of small crustaceans,which play an important ecological role in aquatic ecosystems.They occupy different ecological niches in aquatic food webs,contributes to biogenic element cycles,and transfer of organic matter from primary producers to higher secondary consumers.Copepods also have the potential to展开更多
Saline and hypersaline wetlands account for almost half of the volume of inland water globally.They provide pivotal habitat for a vast range of species,including crucial ecosystem services for humans such as carbon si...Saline and hypersaline wetlands account for almost half of the volume of inland water globally.They provide pivotal habitat for a vast range of species,including crucial ecosystem services for humans such as carbon sink storage and extractive resource reservoirs.Despite their importance,effective ecological assessment is in its infancy compared to current conventional surveys carried out in freshwater ecosystems.The integration of environmental DNA(eDNA)analysis and traditional techniques has the potential to transform biomonitoring processes,particularly in remote and understudied saline environments.In this context,this preliminary study aims to explore the potential of eDNA coupled with conventional approaches by targeting five hypersaline lakes at Rottnest Island(Wadjemup)in Western Australia.We focused on the invertebrate community,a widely accepted key ecological indicator to assess the conservational status in rivers and lakes.The combination of metabarcoding with morphology-based taxonomic analysis described 16 taxa belonging to the orders Anostraca,Diptera,Isopoda,and Coleoptera.DNA-based diversity assessment revealed more taxa at higher taxonomic resolution than the morphology-based taxonomic analysis.However,certain taxa(i.e.,Ephydridae,Stratyiomidae,Ceratopogonidae)were only identified via net surveying.Overall,our results indicate that great potential resides in combining conventional net-based surveys with novel eDNA approaches in saline and hypersaline lakes.Indeed,urgent and effective conservational frameworks are required to contrast the enormous pressure that these ecosystems are increasingly facing.Further investigations at larger spatial temporal scales will allow consolidation of robust,reliable,and affordable biomonitoring frameworks in the underexplored world of saline wetlands.展开更多
Brine resource is rich in China,but its exploitation has been a problem.Hypersaline brine will corrode equipment and materials seriously during the brine exploitation and transportation.The corrosion problem can cause...Brine resource is rich in China,but its exploitation has been a problem.Hypersaline brine will corrode equipment and materials seriously during the brine exploitation and transportation.The corrosion problem can cause great展开更多
In order to investigate the feasibility of biological treatment of bypersaline wastewater produced from toilet flushing with seawater at low temperature, pilot-scale studies were established with plug-flow activated s...In order to investigate the feasibility of biological treatment of bypersaline wastewater produced from toilet flushing with seawater at low temperature, pilot-scale studies were established with plug-flow activated sludge process at low temperature （5-9℃） based on bench-scale experiments. The critical salinity concentration of 30 g/L, which resulted from the cooperation results of the non-halophilic bacteria and the halophilic bacteria, was drawn in bench-scale experiment. Pilot-scale studies showed that high COD removal efficiency, higher than 85 %, was obtained at low temperature when 30 percent seawater [ seawater/（seawater ＋ sewage） ] was introduced. The salinity improved the settleability of activated sludge, and average SV dropped down from 38% to 22. 5% after adding seawater. Sludge bulking could be forborne effectively because filamentous bacteria couldn＇t subsist under high salinity concentration.展开更多
Pilot-scale studies on biological treatment of hypersaline wastewater at low temperature were conducted and results showed that seawater salinity had a strong negative effect on notrouomonas and nitrobaeter growth, bu...Pilot-scale studies on biological treatment of hypersaline wastewater at low temperature were conducted and results showed that seawater salinity had a strong negative effect on notrouomonas and nitrobaeter growth, but much more on the nitrobaeter. The nitrification action was mainly accomplished by nitrosomonas. Bench-scale experiments using two SBRs were carried out for further investigation under different conditions of salinities, ammonia loadings and temperatures. Biological nitrogen removal via nitrite pathway from wastewater containing 30 percent seawater was achieved, but the ammonia removal efficiency was strongly related not only to the influent ammonia loading at different salinities but also to temperatures. When the ratio of seawater to wastewater was 30 percent, and the ammonia loading was below the critical value of 0. 15 kgNH4 ^＋ -N/（ kgMLSS · d） , the ammonia removal efficiency via nitrite pathway was above 90 %. The critical level of ammonia loading was 0. 15, 0. 08 and 0. 03 kgNH4 ^＋ -N/（ kgMLSS · d） respectively at different temperatures of 30℃, 25℃ and 20℃ when the influent ammonia concentration was 60 - 80 mg/L and pH was 7.5 - 8.0.展开更多
1 Introduction The Great Salt Lake(GSL)is the defining hydrological feature of the Great Basin,North America’s largest desert--and it is the largest waterbody in the western USA.Despite the early(Eardley,1938)recogni...1 Introduction The Great Salt Lake(GSL)is the defining hydrological feature of the Great Basin,North America’s largest desert--and it is the largest waterbody in the western USA.Despite the early(Eardley,1938)recognition of"bioherms,"algal layers,and mats covering hundreds of square km of lake area,these features have not been the展开更多
Cellulases are a group of enzymes that are used in many biotechnological processes. Since most of the enzymes synthesised by mesophilic microorganisms are unstable in industrial environments, it is necessary to direct...Cellulases are a group of enzymes that are used in many biotechnological processes. Since most of the enzymes synthesised by mesophilic microorganisms are unstable in industrial environments, it is necessary to direct research towards extremophile cellulolytic microorganisms because the enzymes synthesised by them are stable and active even in harsh physicochemical conditions. In the present investigation, our aim was to isolate and identify some microbial cellulolytic strains from a hypersaline lake located in Romania and to determine their optimal growth conditions. Of a total of 25 microbial strains isolated, only one extreme halotolerant bacterial strain was able to produce an endoglucanase. Based on molecular identification, we identified this cellulolytic strain as a species of Bacillus genus, most closely related to Bacillus zhangzhouensis. Optimal growth conditions were found to be at 15°C, pH 7.5 and 2 M NaCl. Endoglucanase activity of this bacterial strain is influenced by both salinity and temperature. The most significant endoglucanase activity was detected in the presence of 3 M NaCl, after 72 h of incubation at 15°C. In this situation, the amount of glucose released from a volume of 0.5 mL of 2% (w/v) carboxymethyl cellulose substrate is equivalent to 2.05 mg. In conclusion, this study represents the first preliminary characterization of a B. zhangzhouensis strain that has the ability to degrade cellulose and that demonstrates tolerance to high salt concentrations.展开更多
基金support of the Russian Academy of Sciences for the A.O.Kovalevsky Institute of Marine Biological Research of RAS
文摘Filamentous green algae play an important functional role in element cycling and productivity in the diff erent water bodies. In hypersaline lakes and lagoons of the Crimea, filamentous green algae are present and form bottom and floating mats that occupy large areas with high biomass, up to 4–5 kg(wet biomass)/m2. Cladophora spp. dominated in those mats. Five species of filamentous green algae(Chlorophyta) in Lake Chersonesskoye: C ladophora vadorum(Aresch.) Kütz., C. siwaschensis C. Meyer, C. echinus(Biasol.) Kütz., Ulothrix implexa(Kütz.) Kütz., Rhizoclonium tortuosum(Dillw.) Kütz., and seagrass(Angiospermae) R uppia cirrhosa(Petagna) Grande were found. Cladophora spp. and R. cirrhosa were found in the lake throughout the year, other types of algae were encountered episodically. In most cases the biomass of bottom mat exceeded that of the floating mat. In general, the total biomass of the bottom and floating mats in the lake areas at depths up to 30 cm was in a stable range of values from 100 to 290 mg(dry weight)/cm2. Animal and infusorian average abundance in mats reach high values: infusorians—up to 15 000 000 ind./m2, Cletocamptus retrogressus(Copepoda, Harpacticoida)—up to 730 000 ind./m2, Eucypris mareotica(Ostracoda)—up to 91 000 ind./m2 and Chironomidae larvae(Insecta, Diptera)—up to 140 ind./m2. Those values were much higher than in the plankton.
文摘A pool of dormant stages of planktonic organisms in saline lakes is a substantial component in the plankton communities;we need to take it into account to understand plankton dynamics.Hypersaline water bodies in Crimea,the largest peninsula in the Black Sea,constitute a very characteristic and peculiar habitat type in the region.We examined the presence of crustacean resting stages in sediments of dried up sites of the Crimean hypersaline lakes.Sediment samples were taken in 9 different lakes.Experiments performed on the hatching of these resting stages showed the presence of Moina salina(Cladocera),parthenogenetic Artemia and Artemia urmiana(Anostraca),Eucypris mareotica( inflata)(Ostracoda),and Cletocamptus retrogressus(Harpacticoida).Comparing the experimental results obtained with clean dried brine shrimp cysts and those kept in sediment samples,it was noted that clean cysts hatched much faster than those from sediments did.Some components in bottom sediments slow down and desynchronize hatching from resting eggs in different groups of crustaceans.The sediments of different lakes inhibited the nauplii output from Artemia and ostracod resting eggs to different degrees.More data are needed before we can discuss the reasons of this inhibition.The nonsynchronous output of active stages from the bottom resting ones may be an adaptation that allows crustacean species to exist in extreme and unpredictably changing environments,avoiding the risk that all may emerge at once under unsuitable conditions.
基金Supported by the Natural Science Foundation of Qinghai Province(Nos.2020-ZJ-940Q,2014-ZJ-937Q)the West Light Foundation of the Chinese Academy of Sciences(No.E010GC09)the Youth Innovation Promotion Association CAS(No.E010GC15)。
文摘Dissolved organic matter(DOM)plays a vital role in promoting carbon and nutrient cycling.It is a food source for organisms and controls the migration and transformation of trace metals and other contaminants in aquatic systems.The contributions of aquatic DOM to the environment and ecology of a system are closely related to its abundance and chemical structure.In this study,the chemical composition and binding properties of DOM in a hypersaline lake watershed were investigated for the fi rst time using dissolved organic carbon(DOC)analysis,absorption spectroscopy,Fourier transform infrared spectroscopy,pyrolysis-GC-MS(Py-GC-MS),and fl uorescence parallel factor(PARAFAC)analysis combined with Pb(II)titration techniques.The results showed that DOM from the tributaries that fl owed into the lake had a lower DOC content,higher molecular weight,and higher specifi c UV absorbance than the DOM in lake water.Protein-like fl uorophores were mainly found in tributary and lake surface water DOM(LSDOM)and humic-like substances were abundant in lake groundwater DOM(LGDOM).Using this multi-methodological approach,we found that the DOM from the hypersaline lake watershed was mainly from microbial origins,and consisted of aromatics,carbohydrates,and aliphatics.The results from quantitative analysis showed that DOM from the infl owing tributaries contained more aromatics,lower carbohydrates,and lower aliphatics than DOM in the lake.Monocyclic aromatic hydrocarbons and carbohydrates were more abundant in LSDOM than LGDOM.The results from the Pb(II)titration technique coupled with PARAFAC analysis suggested that PARAFAC-derived components had relatively low condition stability constants(log K_(M)<2).Of the two types of lake DOM,the LGDOM had a higher Pb(II)binding potential than the LSDOM.From this study we have improved our understanding of how DOM within a hypersaline lake watershed varies in its composition and potential to bind with metals.
文摘1 Introduction Copepods are a group of small crustaceans,which play an important ecological role in aquatic ecosystems.They occupy different ecological niches in aquatic food webs,contributes to biogenic element cycles,and transfer of organic matter from primary producers to higher secondary consumers.Copepods also have the potential to
基金Supported by the Curtin-BHP alliance within the framework of the“eDNA for Global Environment Studies(eDGES)”program。
文摘Saline and hypersaline wetlands account for almost half of the volume of inland water globally.They provide pivotal habitat for a vast range of species,including crucial ecosystem services for humans such as carbon sink storage and extractive resource reservoirs.Despite their importance,effective ecological assessment is in its infancy compared to current conventional surveys carried out in freshwater ecosystems.The integration of environmental DNA(eDNA)analysis and traditional techniques has the potential to transform biomonitoring processes,particularly in remote and understudied saline environments.In this context,this preliminary study aims to explore the potential of eDNA coupled with conventional approaches by targeting five hypersaline lakes at Rottnest Island(Wadjemup)in Western Australia.We focused on the invertebrate community,a widely accepted key ecological indicator to assess the conservational status in rivers and lakes.The combination of metabarcoding with morphology-based taxonomic analysis described 16 taxa belonging to the orders Anostraca,Diptera,Isopoda,and Coleoptera.DNA-based diversity assessment revealed more taxa at higher taxonomic resolution than the morphology-based taxonomic analysis.However,certain taxa(i.e.,Ephydridae,Stratyiomidae,Ceratopogonidae)were only identified via net surveying.Overall,our results indicate that great potential resides in combining conventional net-based surveys with novel eDNA approaches in saline and hypersaline lakes.Indeed,urgent and effective conservational frameworks are required to contrast the enormous pressure that these ecosystems are increasingly facing.Further investigations at larger spatial temporal scales will allow consolidation of robust,reliable,and affordable biomonitoring frameworks in the underexplored world of saline wetlands.
基金Fiancial support for this work by National High-tech Research and Development Projects (863)the key technology of efficient exploiting deep brine in the YellowRiver delta (Contracts 2012AA061705)
文摘Brine resource is rich in China,but its exploitation has been a problem.Hypersaline brine will corrode equipment and materials seriously during the brine exploitation and transportation.The corrosion problem can cause great
基金Sponsored by the Key Items of National Natural Science Foundation of China (Grant No. 50138010) and National 10th5 -year Scientific Research Project of Ministry of Science and Technology of China (Grant No.2001BA610A-09).
文摘In order to investigate the feasibility of biological treatment of bypersaline wastewater produced from toilet flushing with seawater at low temperature, pilot-scale studies were established with plug-flow activated sludge process at low temperature （5-9℃） based on bench-scale experiments. The critical salinity concentration of 30 g/L, which resulted from the cooperation results of the non-halophilic bacteria and the halophilic bacteria, was drawn in bench-scale experiment. Pilot-scale studies showed that high COD removal efficiency, higher than 85 %, was obtained at low temperature when 30 percent seawater [ seawater/（seawater ＋ sewage） ] was introduced. The salinity improved the settleability of activated sludge, and average SV dropped down from 38% to 22. 5% after adding seawater. Sludge bulking could be forborne effectively because filamentous bacteria couldn＇t subsist under high salinity concentration.
基金Sponsored by the National Natural Science Foundation of China (No. 50138010, 20877086)National 10th 5 Scientific Research Project of Ministry of Science and Technology of China (Grant No.2001BA610A-09)+1 种基金Knowledge Innovation Program of the Chinese Academy of Sciences (RCEES-QN-200706)the Special Funds for Young Scholars of RCEES
文摘Pilot-scale studies on biological treatment of hypersaline wastewater at low temperature were conducted and results showed that seawater salinity had a strong negative effect on notrouomonas and nitrobaeter growth, but much more on the nitrobaeter. The nitrification action was mainly accomplished by nitrosomonas. Bench-scale experiments using two SBRs were carried out for further investigation under different conditions of salinities, ammonia loadings and temperatures. Biological nitrogen removal via nitrite pathway from wastewater containing 30 percent seawater was achieved, but the ammonia removal efficiency was strongly related not only to the influent ammonia loading at different salinities but also to temperatures. When the ratio of seawater to wastewater was 30 percent, and the ammonia loading was below the critical value of 0. 15 kgNH4 ^＋ -N/（ kgMLSS · d） , the ammonia removal efficiency via nitrite pathway was above 90 %. The critical level of ammonia loading was 0. 15, 0. 08 and 0. 03 kgNH4 ^＋ -N/（ kgMLSS · d） respectively at different temperatures of 30℃, 25℃ and 20℃ when the influent ammonia concentration was 60 - 80 mg/L and pH was 7.5 - 8.0.
文摘1 Introduction The Great Salt Lake(GSL)is the defining hydrological feature of the Great Basin,North America’s largest desert--and it is the largest waterbody in the western USA.Despite the early(Eardley,1938)recognition of"bioherms,"algal layers,and mats covering hundreds of square km of lake area,these features have not been the
文摘Cellulases are a group of enzymes that are used in many biotechnological processes. Since most of the enzymes synthesised by mesophilic microorganisms are unstable in industrial environments, it is necessary to direct research towards extremophile cellulolytic microorganisms because the enzymes synthesised by them are stable and active even in harsh physicochemical conditions. In the present investigation, our aim was to isolate and identify some microbial cellulolytic strains from a hypersaline lake located in Romania and to determine their optimal growth conditions. Of a total of 25 microbial strains isolated, only one extreme halotolerant bacterial strain was able to produce an endoglucanase. Based on molecular identification, we identified this cellulolytic strain as a species of Bacillus genus, most closely related to Bacillus zhangzhouensis. Optimal growth conditions were found to be at 15°C, pH 7.5 and 2 M NaCl. Endoglucanase activity of this bacterial strain is influenced by both salinity and temperature. The most significant endoglucanase activity was detected in the presence of 3 M NaCl, after 72 h of incubation at 15°C. In this situation, the amount of glucose released from a volume of 0.5 mL of 2% (w/v) carboxymethyl cellulose substrate is equivalent to 2.05 mg. In conclusion, this study represents the first preliminary characterization of a B. zhangzhouensis strain that has the ability to degrade cellulose and that demonstrates tolerance to high salt concentrations.
