Climate warming and atmospheric nitrogen(N)deposition have profound influences on the terrestrial biosphere.However,how these two global change drivers affect phytoplankton which are important primary producers in wet...Climate warming and atmospheric nitrogen(N)deposition have profound influences on the terrestrial biosphere.However,how these two global change drivers affect phytoplankton which are important primary producers in wetlands with large carbon stocks and complex hydrological fluctuations remain largely unclear.As part of a two-year field experiment in a freshwater wetland,this study was conducted to investigate the effects of nighttime warming and N addition on phytoplankton biomass in the North China Plain.The results showed that neither nighttime warming nor N addition influenced the Shannon-Wiener index of phytoplankton community.Nighttime warming did not change phytoplankton biomass,likely due to the different warming impacts on dominant phyla and in different seasons.Decreased phytoplankton biomass in spring because of the increased water pH and submerged plant coverage was compensated by the enhanced biomass in autumn due to the reduced dissolved oxygen and submerged plant coverage,leading to the neutral change of phytoplankton biomass under warming.Nitrogen addition elevated phytoplankton biomass by 11.6%,which could be attributed to the enhanced nutrient availability and reduced submerged plant coverage.Positive relationships of methane(CH4)emission rates at the water-air interface with phytoplankton biomass indicated the potentially crucial role of phytoplankton in mediating wetland CH4 cycling through photosynthesis-driven metabolisms.The findings suggested the seasonal variation of phytoplankton and their potential responses to nighttime warming and N deposition,which may provide a more accurate basis for assessing the global change-carbon feedback in wetland ecosystems.展开更多
Brackish water(BW)irrigation may cause soil quality deterioration and thereby a decrease in crop yields.Here we examined the impacts of applying gasification filter cake(GFC),intercropping with Portulaca oleracea(PO),...Brackish water(BW)irrigation may cause soil quality deterioration and thereby a decrease in crop yields.Here we examined the impacts of applying gasification filter cake(GFC),intercropping with Portulaca oleracea(PO),and their combination on soil quality,nutrient uptake by plants and tomato yields under BW irrigation.The treatments evaluated included(i)freshwater irrigation(Control),(ii)BW irrigation,(iii)GFC application under BW irrigation(BW+GFC),(iv)intercropping with PO under BW irrigation(BW+PO),and(v)the combined application of GFC and PO under BW irrigation(BW+PO+GFC).Overall,the use of BW for irrigation resulted in a decline in both soil quality(assessed by a soil quality index(SQI)integrating a wide range of key soil properties including salinity,nutrient availability and microbial activities)and crop yields.Nevertheless,when subjected to BW irrigation,the application of GFC successfully prevented soil salinity.Additionally,the intercropping of PO decreased the soil sodium adsorption ratio and improved the absorption of nutrients by plants.As a result,the BW+GFC+PO treatment generally showed higher tomato yield as compared to other BW-related treatments(i.e.BW,BW+GFC and BW+PO).Compared to BW,the BW+GFC+PO treatment had an average increase of 24.7% in the total fruit yield of four Cropping Seasons.Furthermore,the BW+GFC+PO treatment consistently exhibited the highest fruit quality index(FQI).Taken together,the combined application of GFC and PO is effective in promoting soil quality and crop yields under BW irrigation.展开更多
We report here arsenic speciation in 1643 freshwater fish samples,representing 14 common fish species from 53 waterbodies in Alberta,Canada.Arsenic species were extracted from fish muscle tissue.Arsenic species in the...We report here arsenic speciation in 1643 freshwater fish samples,representing 14 common fish species from 53 waterbodies in Alberta,Canada.Arsenic species were extracted from fish muscle tissue.Arsenic species in the extracts were separated using anion-exchange high-performance liquid chromatography(HPLC)and quantified using inductively coupled plasma mass spectrometry(ICPMS).The total arsenic concentrations in fish ranged from 2.8 to 1200μg/kg(in wet weight of sample)(mean 71±101μg/kg),which are all below the 2000μg/kg(wet weight)maximum allowable total arsenic in fish,recommended by the Ontario Ministry of the Environment.In 99.7%,or 1638 of all 1643 freshwater fish samples analyzed,arsenobetaine(AsB)was detectable,with concentrations higher than the method detection limit of 0.25μg/kg(wet weight).Dimethylarsinic acid(DMA)was detectable(concentration>0.25μg/kg)in 92.1%,or 1514 of the 1643 freshwater fish samples.Inorganic arsenate(iAs^(Ⅴ))was detectable(>0.25μg/kg)in 1119 fish(i.e.,68.1% of 1643 samples).Monomethylarsonic acid(MMA)was detectable(>0.25μg/kg)in 418 fish(25.4%of 1643 samples).The concentrations of arsenic species in the 1643 fish samples varied by as much as three orders of magnitude,ranging from below the method detection limit of 0.25μg/kg to the maximum concentrations of 380μg/kg for AsB,150μg/kg for DMA,70μg/kg for iAs^(Ⅴ),and 51μg/kg for MMA.AsB made up 46.1%±26.2% of total arsenic species.Arsenic speciation patterns varied between lake whitefish,northern pike,and walleye,the three most common types of fish analyzed.The relative proportion of DMA in northern pike was larger than in lake whitefish and walleye,and conversely,the relative proportion of iAs^(Ⅴ) was lower in northern pike.Seven unknown arsenic species were detected,and their chromatographic retention time did not match with those of available arsenic standards.At least one unknown arsenic species was detected in 33.4%,or 549 of 1643 freshwater fish samples.The concentrations of unknown arsenic species were as high as 61μg/kg.Future research is necessary to identify unknown arsenic species and to determine contributing factors to the observed arsenic species patterns and concentrations.展开更多
Fish constitutes the main protein source for the Amazonian population.However,the impact of different anthropogenic activities on trace element and metal accumulation in fish and their risks for human health at a regi...Fish constitutes the main protein source for the Amazonian population.However,the impact of different anthropogenic activities on trace element and metal accumulation in fish and their risks for human health at a regional scale remain largely unexplored.Here we assessed exposure levels of 10 trace elements andmetals(Cr,Mn,Fe,Ni,Cu,Zn,As,Cd,Pb,and Hg)in 56 samples belonging to 11 different species of fish from the Brazilian Amazon.We studied the relationship between exposure levels,fish origin,and fish feeding habits,and assessed toxicological and carcinogenic risks for the Amazonian population.No significant correlation was found between sampling site and exposure levels to the studied elements,but a significant difference was found between the accumulation of some metals and the position of the fish species in the food chain.The concentrations of Cr and Hg in fish flesh were found to exceed the Brazilian limits for human consumption.This study shows that current fish consumption patterns can lead to estimated daily intakes of Hg,As and Cr that exceed the oral reference dose,thus posing a toxicological concern.Furthermore,carcinogenic risks may be expected due to the continued exposure to Cr and As.The results of this study show that the consumption of wild caught fish in the Amazon region should be controlled.Moreover,continued monitoring of trace element and metal contamination in fish and on the health of the Amazonian population is recommended,particularly for riverine and indigenous communities.展开更多
Nearly a quarter of animals living in rivers,lakes and other freshwater sources are threatened with extinction,according to new research published on Wednesday.“Huge rivers like the Amazon River can appear mighty,but...Nearly a quarter of animals living in rivers,lakes and other freshwater sources are threatened with extinction,according to new research published on Wednesday.“Huge rivers like the Amazon River can appear mighty,but at the same time,freshwater environments are very weak,”said the study's co⁃author Patricia Charvet,a biologist at Brazil's Federal University of Ceará.展开更多
Most fish exhibit remarkable morphological diversity,which is often influenced by genetic variation and ecological pressures.Consequently,these are the outcomes of organisms’responses to their environment.Meanwhile,m...Most fish exhibit remarkable morphological diversity,which is often influenced by genetic variation and ecological pressures.Consequently,these are the outcomes of organisms’responses to their environment.Meanwhile,modern morphometrics can quantify shape variation within species of the same group.This study aims to determine the body shape variation of Glossogobius giuris from Lake Mainit,Agusan Del Norte,Philippines.60 adult,uniform-sized fish samples were collected and subjected to standardized laboratory procedures.Further,the samples were digitized for 16 homologous landmark points and loaded into Symmetry Asymmetry Geometric Data(SAGE)Software.Across the tested factors—individuals,sides,and individual x sides—result shows that shape variations among individuals were highly significant(F=2.1045,p<0.0001),along with among males(F=3.2711,p<0.0001).Females exhibited higher Fluctuating Asymmetry(FA)(F=18.99,p<0.0001)compared to males(F=7.0964,p<0.0001).It suggests morphological shape differences across the sexes,and the shape variation observed could be a response to environmental perturbations.Shape variations were associated with swimming,food hunting,and predator defense.Moreover,Principal Component Analysis(PCA)demonstrates higher scores of FA in females(81.96%)than in males(74.76%).It was noticed that females had a high fluctuating asymmetry.It might be due to various physiological and ecological pressures compared to males.The observed levels of directional and fluctuating asymmetry in males and females,respectively,may indicate sex-linked morphological and developmental processes,which are important to consider in ecological or evolutionary contexts.Thus,utilizing geometric morphometrics can depict subtle differences across the same populations.展开更多
The integrated technology of interfacial solar steam generation and photo-Fenton oxidation has emerged as a promising way to simultaneously mitigate freshwater scarcity and degrade organic pollutants.However,fabricati...The integrated technology of interfacial solar steam generation and photo-Fenton oxidation has emerged as a promising way to simultaneously mitigate freshwater scarcity and degrade organic pollutants.However,fabricating low-cost,multi-functional evaporators with high water evaporation and catalytic ability still presents a significant challenge.Herein,we report the functional upcycling of waste polyimide into semiconducting Fe-BTEC and subsequently construct Fe-BTEC-based composite evaporators for simultaneous freshwater production and photo-Fenton degradation of pollutants.Firstly,through a two-step solvothermal-solution stirring method,Fe-BTEC nanoparticles with the size of 20-100 nm are massively produced from waste polyimide,with a band gap energy of 2.2 eV.The composite evaporator based on Fe-BTEC and graphene possesses wide solar-spectrum absorption capacity,high photothermal conversion capacity,rapid delivery of water,and low enthalpy of evaporation.Benefiting from the merits above,the composite evaporator achieves a high evaporation rate of 2.72kgm^(-2) h^(-1) from tetracycline solution,as well as the photothermal conversion efficiency of 97%when exposed to irradiation of 1 Sun,superior to many evaporators.What is more,the evaporator exhibits the tetracycline degradation rate of 99.6%with good recycling stability,ranking as one of the most powerful heterogeneous Fenton catalysts.COMSOL Multiphysics and density functional theory calculation results prove the synergistic effect of the concentrated heat produced by interfacial solar steam generation and catalytic active sites of Fe-BTEC on promoting H_(2)O_(2) activation to form reactive oxidation radicals.This work not only provides a green strategy for upcycling waste polyimide,but also proposes a new approach to fabricate multi-functional evaporators.展开更多
Salinity is a fundamental variable of watermass chemistry,often varying strongly in coastal,estuarine,lagoonal,restricted-marine basinal,and non-freshwater lacustrine systems(Figure 1).Salinity variation commonly cont...Salinity is a fundamental variable of watermass chemistry,often varying strongly in coastal,estuarine,lagoonal,restricted-marine basinal,and non-freshwater lacustrine systems(Figure 1).Salinity variation commonly controls other watermass properties(e.g.,redox,temperature,p H,and chemical composition)as well as nutrient levels(and thus bioproductivity).展开更多
Despite most eel gobies(Gobionellidae:Amblyopinae)have inhabited brackish or marine waters,few species(such as Taenioides sp.)have been found to invade multiple inland freshwaters via artificial water transfer project...Despite most eel gobies(Gobionellidae:Amblyopinae)have inhabited brackish or marine waters,few species(such as Taenioides sp.)have been found to invade multiple inland freshwaters via artificial water transfer projects.The habitat transfers from brackish water to freshwater zones of Taenioides sp.have caused severe damage to Chinese aquatic ecosystems in recent years.Unfortunately,the molecular mechanism underlying freshwater invasion remains poorly understood.Considering changes of environmental factors,especially salinity,are bound to adjust the demands for energy affected by mitochondria via oxidative phosphorylation,13 Amblyopinae mitogenomes were compared,including the newly assembled Taenioides sp.mitogenome in this study.Comparative mitogenomic analyses revealed a highly conserved structure,composition and arrangements,with the exception of variable control region(CR).All of the CRs possessed tandem repeat sequences except Trypauchenopsis sp.G341,differing in motifs and number of copies,which was the dominant factor resulting in length heterogeneity of CR.The phylogenetic trees reconfirmed the paraphyletic origin of Amblyopinae with respect to Oxudercinae,supporting that these two subfamilies should be merged as an expansion of phenotypic variation within the“terrestrial goby”clade.Furthermore,four protein coding genes(COI,ND3,ND5 and Cyt b)in Taenioides sp.mitogenome have experienced adaptive evolution,indicating their important roles in enhancing the efficiency of ATP production to cope with the osmotic regulation adjustment and reach its current widespread distribution in multiple inland freshwaters of China.These results revealed the functional importance of mitochondrial genes,and provided fresh insights into the molecular mechanisms underlying the freshwater invasion.Also,our results may provide critical reference value for the future control of other invasive species.展开更多
Every year,during the rainy season,a scenic road winding through China's Poyang Lake like a mythical(虚构的)dragon becomes flooded,offering a unique driving and visual experience.Yongwu Road is the only stretch of...Every year,during the rainy season,a scenic road winding through China's Poyang Lake like a mythical(虚构的)dragon becomes flooded,offering a unique driving and visual experience.Yongwu Road is the only stretch of road connecting Wucheng,one of the oldest townships in China,to neighboring townships and counties.Part of the X219 county road,this 5.05 km piece of infrastructure was built straight through Poyang Lake,China's largest freshwater lake,making it one of the most famous tourist attractions of Jiangxi Province.But Yongwu Road is most popular with tourists at the onset of the rainy season,during spring when the water level starts rising.When the level of the surrounding lake reaches about 18.6 meters,water submerges(淹没)part of the road,turning Yongwu Road into“China's most beautiful road under the water”展开更多
Siberian taimen Hucho taimen(Pallas,1773)is a broadly distributed and popular sport fish with high economic value.However,low abundance and hard-to-reach habitat make the Siberian taimen a relatively understudied spec...Siberian taimen Hucho taimen(Pallas,1773)is a broadly distributed and popular sport fish with high economic value.However,low abundance and hard-to-reach habitat make the Siberian taimen a relatively understudied species.Here we describe the morphological variability of two size groups of Siberian taimen juveniles from the eastern(Amur River basin)and western(Kama River basin)parts of the species distribution.The largest morphological differentiation of Siberian taimen juveniles was observed at the inter-basin level.In the Amur River basin,Siberian taimen juveniles also differed morphologically even at sites located at a distance of 20 km from each other,which may be explained by a small home-range inhabitation of juveniles leading to the formation of their morphotype determined by local environmental conditions.The pattern of allometry varies in taimen from different rivers,which could be related to the ontogenetic shift of ecological niches and the level of heterogeneity of the river environment.展开更多
In recent years,microplastics(MPs)in freshwater lake have been receiving increasing attention;however,the microbial communities on the surface of MPs have not been well studied.To investigate the potential risk posed ...In recent years,microplastics(MPs)in freshwater lake have been receiving increasing attention;however,the microbial communities on the surface of MPs have not been well studied.To investigate the potential risk posed by MPs to the lake ecosystem and its surface microbial community structure,MPs samples were collected in September 2023 in the freshwater Dongting Lake,Hunan,China,at five sites,and the differences in bacterial species community composition and structure between MPs and water samples were analyzed.Results show that MPs(13.71±3.32 items/L)in the samples were mostly black in color,fiber in shape,and PES in composition,and those<0.5 mm in size are dominant.The bacterial composition in water was different from that on MPs.At phylum level,Proteobacteria,Actinobacteria,Cyanobacteria,and Bacteroidetes were dominated in relative abundance in both water and MPs.Proteobacteria was more abundant in MPs than in water.The relative abundance of Bacteroidota and Actinobacteriota was significantly lower in MPs than in water.At genus level,Pantoea and Pseudomonas were potentially pathogenic genera in MPs surfaces.The presence of Cyanobacteria and pathogenic bacteria is undoubtedly a potential risk to the deterioration of the water quality.This study revealed the difference in the distribution of bacterial community in water and MPs in Dongting Lake and provided new perspectives to further understanding of MPs pollution in freshwater lakes.展开更多
Biological nitrogen fixation(BNF)is a crucial process that provides bioavailable nitrogen and supports primary production in freshwater lake ecosystems.However,the characteristics of diazotrophic community and nitroge...Biological nitrogen fixation(BNF)is a crucial process that provides bioavailable nitrogen and supports primary production in freshwater lake ecosystems.However,the characteristics of diazotrophic community and nitrogenase activity in freshwater lake sediments remain poorly understood.Here,we investigated the diazotrophic communities and nitrogenase activities in the sediments of three large river-connected freshwater lakes in eastern China using 15N-isotope tracing and nifH sequencing.The sediments in these lakes contained diverse nitrogenase genes that were phylogenetically grouped into Clusters I and III.The diazotrophic communities in the sedimentswere dominated by stochastic processes in Hongze Lake and Taihu Lake,which had heterogeneous habitats and shallower water depths,while in Poyang Lake,which had deeper water and a shorter hydraulic retention time,the assembly of the diazotrophic community in the sediments was dominated by homogeneous selection processes.Temperature and water depth were also found the key environmental factors affecting the sediment diazotrophic communities.Sediment nitrogenase activities varied in the three lakes and within distinct regions of an individual lake,ranging from 0 to 14.58 nmol/(kg·hr).Nitrogenase activity was significantly correlated with ferric iron,total phosphorus,and organic matter contents.Our results suggested that freshwater lake sediment contain high diversity of nitrogen-fixing microorganisms with potential metabolic diversity,and the community assembly patterns and nitrogenase activities varied with the lake habitat.展开更多
To assess the population development of submerged plant species in disturbed lake ecosystems,we need to better understand the genetic diversity and spatial genetic structure at a fine scale,as well as the impact of di...To assess the population development of submerged plant species in disturbed lake ecosystems,we need to better understand the genetic diversity and spatial genetic structure at a fine scale,as well as the impact of disturbances on the populations.Caohai Lake,in southwest China,is a suitable natural sampling lake because of its abundance of submerged plants and the intense human disturbance.Three widely distributed species,Potamogeton lucens,Ceratophyllum demersum,and Myriophyllum spicatum,were sampled;the spatial position of each individual was recorded in two-dimensional coordinates;and the species were analyzed genetically using microsatellite markers.Among the species studied,M.spicatum exhibited the highest genetic and clonal diversities.All P.lucens subpopulations but one showed a significant fine-scale spatial genetic structure(FSGS),which may result from the limited gene dispersal.However,M.spicatum and C.demersum,with a relatively large distance of gene dispersal,had no significant FSGS.The FSGS pattern of P.lucens at the dock site with intense boat disturbance was significantly different from that at other sites.Our results imply that the FSGS of submerged plants is affected by many factors including seed dispersal,vegetative reproduction and disturbance from birds and boats.Most subpopulations of the three species hadσ_(sex)^(2)/σ_(veg)^(2)values greater than one,implying that the sexual dispersal contributes more than vegetative dispersal to total gene dispersal.Therefore,it is worth paying attention to the importance of seed dispersal for population development of submerged plants in lake ecosystems.展开更多
Whether clay-rich shale reservoirs with low-medium maturity can serve as primary exploration targets remains a focal point of debate in the academic community.Clarifying the exploration potential of clayrich shale res...Whether clay-rich shale reservoirs with low-medium maturity can serve as primary exploration targets remains a focal point of debate in the academic community.Clarifying the exploration potential of clayrich shale reservoirs is crucial for the future exploration and development of lacustrine shale.The Triassic Yanchang Formation in the Ordos Basin has been one of most productive lacustrine shale oil systems in China,with substantial oil production capacity already established.While the primary productive layers are currently fine-grained siltstone interbeds,however,it remains a highly debated issue whether the volumetrically more significant clay-rich reservoirs can become viable exploration targets in the near future.To address this issue,we examined the exploration potential of different lithofacies assemblages in Member 7(Mbr 7)of the Triassic Yanchang Formation,using a borehole in the Tongchuan area of the southern Ordos Basin as an example.We identified favorable exploration targets and assessed whether clay-rich reservoirs formed predominantly-freshwater conditions can become viable exploration targets.The results indicate the presence of six lithofacies in clay-rich reservoirs of Mbr 7 of the Yanchang Formation,with two main lithofacies assemblages:laminated organic-rich shale and massive mudstone.From the perspective of sandstone distribution,the sandstone interlayers within laminated organic-rich shale are primarily formed by gravity(hyperpycnal)flows,while sandstones deposited in delta front environments are typically associated with massive mudstone.Laminated organic-rich shale deposition occurred in an anoxic,deep-water environment characterized by high primary productivity,whereas massive mudstone formed in environments with high sedimentation rates and substantial terrigenous debris influx.Currently,the exploration potential of sandstone interlayers exceeds that of clay-rich reservoirs,with the greatest potential observed in the sandstone interlayers associated with laminated organic-rich shale formed by gravity(hyperpycnal)flows.Comparative analysis reveals that clay-rich reservoirs with low to medium maturity present great challenges for exploitation,making interlayer-type reservoirs the main focus of exploration at this stage.Nevertheless,clay-rich reservoirs in closed systems with high thermal maturity and organic matter content also hold considerable potential.展开更多
Donghua University develops novel photothermal fabric to address freshwater crisis 2D photothermal membranes have demonstrated numerous advantages in solar desalination due to their flexibility,scalability,and low cos...Donghua University develops novel photothermal fabric to address freshwater crisis 2D photothermal membranes have demonstrated numerous advantages in solar desalination due to their flexibility,scalability,and low cost.However,their practical applications are limited by the restricted evaporation area and obstructed vapor channels.The research team led by Chen Zhigang,a researcher from the State Key Laboratory of Advanced Fiber Materials and the School of Materials Science and Engineering at Donghua University,has designed a novel biomimetic photothermal fabric,which is composed of two carbon-nanotube-hydrogel-coated polyester(PET)fabrics separated by fiber pillars,with the upper fabric layer having a hole array as stomatal channels.This fabric shows high solar-absorption efficiency(96.1%)and decreased water-evaporation enthalpy(1664.6 kJ kg^(-1)).展开更多
Arsenic speciation in freshwater fish is crucial for providing meaningful consumption guidelines that allow the public to make informed decisions regarding its consumption.While marine fish have attractedmuch research...Arsenic speciation in freshwater fish is crucial for providing meaningful consumption guidelines that allow the public to make informed decisions regarding its consumption.While marine fish have attractedmuch research interest due to their higher arsenic content,research on freshwater fish is limited due to the challenges in quantifying and identifying arsenic species present at trace levels.We describe here a sensitivemethod and its application to the quantification of arsenic species in freshwater fish.Arsenic species from fish tissues were extracted using a methanol/water mixture(1:1 vol.ratio)and ultrasound sonication.Anion-exchange high-performance liquid chromatography(HPLC)enabled separation of arsenobetaine(AsB),inorganic arsenite(iAs^(Ⅲ)),dimethylarsinic acid(DMA),monomethylarsonic acid(MMA),inorganic arsenate(iAs^(Ⅴ)),and three new arsenic species.Inductively coupled plasma mass spectrometry(ICPMS)provided highly sensitive and specific detection of arsenic.A limit of detection of 0.25μg/kg(wet weight fish tissue)was achieved for the five target arsenic species:AsB,iAs^(Ⅲ),DMA,MMA,and iAs^(Ⅴ).A series of experimentswere conducted to ensure the accuracy and validity of the analytical method.The method was successfully applied to the determination of arsenic species in lakewhitefish,northern pike,and walleye,with AsB,DMA,and iAs^(Ⅴ) being frequently detected.Three new arsenic species were detected,but their chromatographic retention times did not match with those of any available arsenic standards.Future research is necessary to elucidate the identity of these new arsenic species detected in freshwater fish.展开更多
The reasonable development and design of high-efficiency and low-cost electrocatalysts for hydrogen evolution reaction(HER)under industrial current densities are imperative for achieving carbon neutrality,while also p...The reasonable development and design of high-efficiency and low-cost electrocatalysts for hydrogen evolution reaction(HER)under industrial current densities are imperative for achieving carbon neutrality,while also posing challenges.In this study,an efficient electrocatalyst is successfully constructed through electrodeposition methods,which consists of monodispersed Pt loaded on amorphous/crystalline nickel–iron layered double hydroxide(Pt-SAs/ac-NiFe LDH).The Pt-SAs/ac-NiFe LDH demonstrates an elevated mass activity of 17.66 A mg_(Pt)^(−1)and a significant turnover frequency of 17.90 s^(−1)for HER in alkaline conditions under the overpotential of 100 mV.Meanwhile,for alkaline freshwater and seawater,Pt-SAs/ac-NiFe LDH exhibits ultra-low overpotentials of 141 and 138 mV to reach 1000 mA cm^(−2),respectively.Remarkably,it maintains stable operation for 100 h at 500 mA cm^(−2),showcasing its robustness and reliability.In situ Raman spectra reveal that Pt single atoms(Pt-SAs)accelerate interfacial water dissociation,thereby enhancing the HER kinetics in Pt-SAs/ac-NiFe LDH.Furthermore,theoretical calculation results show significant electronic interaction between the Pt-SAs and the ac-NiFe LDH support.The interaction significantly enhances water adsorption and dissociation,and balances the adsorption/desorption of hydrogen intermediates,ultimately improving HER performance.This research provides a viable method for designing efficient HER catalysts for water electrolysis in alkaline freshwater and seawater under industrial current densities.展开更多
[Objective] The aim was to establish the water quality evaluation index system for freshwater aquaculture pond.[Method] The expert survey,DELPHI,field research and other methods were used.Based on the analysis of fact...[Objective] The aim was to establish the water quality evaluation index system for freshwater aquaculture pond.[Method] The expert survey,DELPHI,field research and other methods were used.Based on the analysis of factors influencing water quality of freshwater aquaculture pond,and the importance degree of 14 factors influencing water quality of freshwater aquaculture pond was ordered.Then,five factors were selected as index to establish the water quality evaluation index system of freshwater aquaculture with the determination for thresholds of these factors.[Result] The importance degree of water quality of freshwater aquaculture pond showed an order of Dissolved oxygenpHPhytoplankton biomassSecchi depthTotal NitrogenZooplankton biomassWater temperatureBiochemical Oxygen DemandWater colorSalinityTotal hardness;according to the value of importance degree,the dissolved oxygen,pH,secchi depth,phytoplankton biomass and total nitrogen these five factors were selected as the index system of water quality evaluation of pond.The level of water quality of freshwater aquaculture pond was divided into five,and the tolerance range of fish to each index was obtained by expert observation.[Conclusion] This study had provided a scientific basis for water quality evaluation system of freshwater aquaculture pond.展开更多
The establishment of water circulation aquaculture system realized the hi- erarchical use of nitrogen, phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource. H...The establishment of water circulation aquaculture system realized the hi- erarchical use of nitrogen, phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource. However, no research has been reported on the detailed calculation of the relationship between the area of aquaculture pond and purification pond. In this study, referring to the absorption ability of aquatic plants to pollutants in aquaculture wastewater and pollutant generation and discharge coefficient in aquaculture pond, based on the general rules of water quality management in freshwater aquaculture system, a calculation mode was es- tablished to investigate the relationship between the area of aquaculture pond and purification pond in freshwater recirculation aquaculture system, which was feasible to explain related cases and would provide theoretical basis to reduce the economic costs in the construction of water circulation aquaculture system and realize the bal- ance between the ecological benefits and the economic benefits.展开更多
基金supported by the Science and Technology Project of Hebei Education Department(No.QN2023028)the Natural Science Foundation of Hebei Province(No.C2022201042)+1 种基金the High-level Talent Research Funding Project of Hebei University(Nos.521000981405 and 521000981186)the Collaborative Innovation Center for Baiyangdian Basin Ecological Protection and Beijing-Tianjin-Hebei Sustainable Development.
文摘Climate warming and atmospheric nitrogen(N)deposition have profound influences on the terrestrial biosphere.However,how these two global change drivers affect phytoplankton which are important primary producers in wetlands with large carbon stocks and complex hydrological fluctuations remain largely unclear.As part of a two-year field experiment in a freshwater wetland,this study was conducted to investigate the effects of nighttime warming and N addition on phytoplankton biomass in the North China Plain.The results showed that neither nighttime warming nor N addition influenced the Shannon-Wiener index of phytoplankton community.Nighttime warming did not change phytoplankton biomass,likely due to the different warming impacts on dominant phyla and in different seasons.Decreased phytoplankton biomass in spring because of the increased water pH and submerged plant coverage was compensated by the enhanced biomass in autumn due to the reduced dissolved oxygen and submerged plant coverage,leading to the neutral change of phytoplankton biomass under warming.Nitrogen addition elevated phytoplankton biomass by 11.6%,which could be attributed to the enhanced nutrient availability and reduced submerged plant coverage.Positive relationships of methane(CH4)emission rates at the water-air interface with phytoplankton biomass indicated the potentially crucial role of phytoplankton in mediating wetland CH4 cycling through photosynthesis-driven metabolisms.The findings suggested the seasonal variation of phytoplankton and their potential responses to nighttime warming and N deposition,which may provide a more accurate basis for assessing the global change-carbon feedback in wetland ecosystems.
基金supported by the Key Research and Development Program of Ningxia(Grant No.2023BCF01046)。
文摘Brackish water(BW)irrigation may cause soil quality deterioration and thereby a decrease in crop yields.Here we examined the impacts of applying gasification filter cake(GFC),intercropping with Portulaca oleracea(PO),and their combination on soil quality,nutrient uptake by plants and tomato yields under BW irrigation.The treatments evaluated included(i)freshwater irrigation(Control),(ii)BW irrigation,(iii)GFC application under BW irrigation(BW+GFC),(iv)intercropping with PO under BW irrigation(BW+PO),and(v)the combined application of GFC and PO under BW irrigation(BW+PO+GFC).Overall,the use of BW for irrigation resulted in a decline in both soil quality(assessed by a soil quality index(SQI)integrating a wide range of key soil properties including salinity,nutrient availability and microbial activities)and crop yields.Nevertheless,when subjected to BW irrigation,the application of GFC successfully prevented soil salinity.Additionally,the intercropping of PO decreased the soil sodium adsorption ratio and improved the absorption of nutrients by plants.As a result,the BW+GFC+PO treatment generally showed higher tomato yield as compared to other BW-related treatments(i.e.BW,BW+GFC and BW+PO).Compared to BW,the BW+GFC+PO treatment had an average increase of 24.7% in the total fruit yield of four Cropping Seasons.Furthermore,the BW+GFC+PO treatment consistently exhibited the highest fruit quality index(FQI).Taken together,the combined application of GFC and PO is effective in promoting soil quality and crop yields under BW irrigation.
基金supported by Alberta Health,Alberta Innovates,the Canada Research Chairs program,the Canadian Institutes of Health Research,and the Natural Sciences and Engineering Research Council of Canada.
文摘We report here arsenic speciation in 1643 freshwater fish samples,representing 14 common fish species from 53 waterbodies in Alberta,Canada.Arsenic species were extracted from fish muscle tissue.Arsenic species in the extracts were separated using anion-exchange high-performance liquid chromatography(HPLC)and quantified using inductively coupled plasma mass spectrometry(ICPMS).The total arsenic concentrations in fish ranged from 2.8 to 1200μg/kg(in wet weight of sample)(mean 71±101μg/kg),which are all below the 2000μg/kg(wet weight)maximum allowable total arsenic in fish,recommended by the Ontario Ministry of the Environment.In 99.7%,or 1638 of all 1643 freshwater fish samples analyzed,arsenobetaine(AsB)was detectable,with concentrations higher than the method detection limit of 0.25μg/kg(wet weight).Dimethylarsinic acid(DMA)was detectable(concentration>0.25μg/kg)in 92.1%,or 1514 of the 1643 freshwater fish samples.Inorganic arsenate(iAs^(Ⅴ))was detectable(>0.25μg/kg)in 1119 fish(i.e.,68.1% of 1643 samples).Monomethylarsonic acid(MMA)was detectable(>0.25μg/kg)in 418 fish(25.4%of 1643 samples).The concentrations of arsenic species in the 1643 fish samples varied by as much as three orders of magnitude,ranging from below the method detection limit of 0.25μg/kg to the maximum concentrations of 380μg/kg for AsB,150μg/kg for DMA,70μg/kg for iAs^(Ⅴ),and 51μg/kg for MMA.AsB made up 46.1%±26.2% of total arsenic species.Arsenic speciation patterns varied between lake whitefish,northern pike,and walleye,the three most common types of fish analyzed.The relative proportion of DMA in northern pike was larger than in lake whitefish and walleye,and conversely,the relative proportion of iAs^(Ⅴ) was lower in northern pike.Seven unknown arsenic species were detected,and their chromatographic retention time did not match with those of available arsenic standards.At least one unknown arsenic species was detected in 33.4%,or 549 of 1643 freshwater fish samples.The concentrations of unknown arsenic species were as high as 61μg/kg.Future research is necessary to identify unknown arsenic species and to determine contributing factors to the observed arsenic species patterns and concentrations.
基金supported by the National Geographic Society through an early career grant to A.Rico (EC-59809C-19)Support Programme-PlanGenT (CIDEGENT/2020/043)of the Generalitat ValencianaR.Oliveira acknowledges"Fundacao de Amparo a Pesquisa do Estado de Sao Paulo"-FAPESP (Project 2018/03108-0).
文摘Fish constitutes the main protein source for the Amazonian population.However,the impact of different anthropogenic activities on trace element and metal accumulation in fish and their risks for human health at a regional scale remain largely unexplored.Here we assessed exposure levels of 10 trace elements andmetals(Cr,Mn,Fe,Ni,Cu,Zn,As,Cd,Pb,and Hg)in 56 samples belonging to 11 different species of fish from the Brazilian Amazon.We studied the relationship between exposure levels,fish origin,and fish feeding habits,and assessed toxicological and carcinogenic risks for the Amazonian population.No significant correlation was found between sampling site and exposure levels to the studied elements,but a significant difference was found between the accumulation of some metals and the position of the fish species in the food chain.The concentrations of Cr and Hg in fish flesh were found to exceed the Brazilian limits for human consumption.This study shows that current fish consumption patterns can lead to estimated daily intakes of Hg,As and Cr that exceed the oral reference dose,thus posing a toxicological concern.Furthermore,carcinogenic risks may be expected due to the continued exposure to Cr and As.The results of this study show that the consumption of wild caught fish in the Amazon region should be controlled.Moreover,continued monitoring of trace element and metal contamination in fish and on the health of the Amazonian population is recommended,particularly for riverine and indigenous communities.
文摘Nearly a quarter of animals living in rivers,lakes and other freshwater sources are threatened with extinction,according to new research published on Wednesday.“Huge rivers like the Amazon River can appear mighty,but at the same time,freshwater environments are very weak,”said the study's co⁃author Patricia Charvet,a biologist at Brazil's Federal University of Ceará.
文摘Most fish exhibit remarkable morphological diversity,which is often influenced by genetic variation and ecological pressures.Consequently,these are the outcomes of organisms’responses to their environment.Meanwhile,modern morphometrics can quantify shape variation within species of the same group.This study aims to determine the body shape variation of Glossogobius giuris from Lake Mainit,Agusan Del Norte,Philippines.60 adult,uniform-sized fish samples were collected and subjected to standardized laboratory procedures.Further,the samples were digitized for 16 homologous landmark points and loaded into Symmetry Asymmetry Geometric Data(SAGE)Software.Across the tested factors—individuals,sides,and individual x sides—result shows that shape variations among individuals were highly significant(F=2.1045,p<0.0001),along with among males(F=3.2711,p<0.0001).Females exhibited higher Fluctuating Asymmetry(FA)(F=18.99,p<0.0001)compared to males(F=7.0964,p<0.0001).It suggests morphological shape differences across the sexes,and the shape variation observed could be a response to environmental perturbations.Shape variations were associated with swimming,food hunting,and predator defense.Moreover,Principal Component Analysis(PCA)demonstrates higher scores of FA in females(81.96%)than in males(74.76%).It was noticed that females had a high fluctuating asymmetry.It might be due to various physiological and ecological pressures compared to males.The observed levels of directional and fluctuating asymmetry in males and females,respectively,may indicate sex-linked morphological and developmental processes,which are important to consider in ecological or evolutionary contexts.Thus,utilizing geometric morphometrics can depict subtle differences across the same populations.
基金supported by the National Natural Science Foundation of China(No.52373099)the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(No.B21003)。
文摘The integrated technology of interfacial solar steam generation and photo-Fenton oxidation has emerged as a promising way to simultaneously mitigate freshwater scarcity and degrade organic pollutants.However,fabricating low-cost,multi-functional evaporators with high water evaporation and catalytic ability still presents a significant challenge.Herein,we report the functional upcycling of waste polyimide into semiconducting Fe-BTEC and subsequently construct Fe-BTEC-based composite evaporators for simultaneous freshwater production and photo-Fenton degradation of pollutants.Firstly,through a two-step solvothermal-solution stirring method,Fe-BTEC nanoparticles with the size of 20-100 nm are massively produced from waste polyimide,with a band gap energy of 2.2 eV.The composite evaporator based on Fe-BTEC and graphene possesses wide solar-spectrum absorption capacity,high photothermal conversion capacity,rapid delivery of water,and low enthalpy of evaporation.Benefiting from the merits above,the composite evaporator achieves a high evaporation rate of 2.72kgm^(-2) h^(-1) from tetracycline solution,as well as the photothermal conversion efficiency of 97%when exposed to irradiation of 1 Sun,superior to many evaporators.What is more,the evaporator exhibits the tetracycline degradation rate of 99.6%with good recycling stability,ranking as one of the most powerful heterogeneous Fenton catalysts.COMSOL Multiphysics and density functional theory calculation results prove the synergistic effect of the concentrated heat produced by interfacial solar steam generation and catalytic active sites of Fe-BTEC on promoting H_(2)O_(2) activation to form reactive oxidation radicals.This work not only provides a green strategy for upcycling waste polyimide,but also proposes a new approach to fabricate multi-functional evaporators.
文摘Salinity is a fundamental variable of watermass chemistry,often varying strongly in coastal,estuarine,lagoonal,restricted-marine basinal,and non-freshwater lacustrine systems(Figure 1).Salinity variation commonly controls other watermass properties(e.g.,redox,temperature,p H,and chemical composition)as well as nutrient levels(and thus bioproductivity).
基金The National Natural Science Foundation of China under contract Nos 42171069 and 41976121.
文摘Despite most eel gobies(Gobionellidae:Amblyopinae)have inhabited brackish or marine waters,few species(such as Taenioides sp.)have been found to invade multiple inland freshwaters via artificial water transfer projects.The habitat transfers from brackish water to freshwater zones of Taenioides sp.have caused severe damage to Chinese aquatic ecosystems in recent years.Unfortunately,the molecular mechanism underlying freshwater invasion remains poorly understood.Considering changes of environmental factors,especially salinity,are bound to adjust the demands for energy affected by mitochondria via oxidative phosphorylation,13 Amblyopinae mitogenomes were compared,including the newly assembled Taenioides sp.mitogenome in this study.Comparative mitogenomic analyses revealed a highly conserved structure,composition and arrangements,with the exception of variable control region(CR).All of the CRs possessed tandem repeat sequences except Trypauchenopsis sp.G341,differing in motifs and number of copies,which was the dominant factor resulting in length heterogeneity of CR.The phylogenetic trees reconfirmed the paraphyletic origin of Amblyopinae with respect to Oxudercinae,supporting that these two subfamilies should be merged as an expansion of phenotypic variation within the“terrestrial goby”clade.Furthermore,four protein coding genes(COI,ND3,ND5 and Cyt b)in Taenioides sp.mitogenome have experienced adaptive evolution,indicating their important roles in enhancing the efficiency of ATP production to cope with the osmotic regulation adjustment and reach its current widespread distribution in multiple inland freshwaters of China.These results revealed the functional importance of mitochondrial genes,and provided fresh insights into the molecular mechanisms underlying the freshwater invasion.Also,our results may provide critical reference value for the future control of other invasive species.
文摘Every year,during the rainy season,a scenic road winding through China's Poyang Lake like a mythical(虚构的)dragon becomes flooded,offering a unique driving and visual experience.Yongwu Road is the only stretch of road connecting Wucheng,one of the oldest townships in China,to neighboring townships and counties.Part of the X219 county road,this 5.05 km piece of infrastructure was built straight through Poyang Lake,China's largest freshwater lake,making it one of the most famous tourist attractions of Jiangxi Province.But Yongwu Road is most popular with tourists at the onset of the rainy season,during spring when the water level starts rising.When the level of the surrounding lake reaches about 18.6 meters,water submerges(淹没)part of the road,turning Yongwu Road into“China's most beautiful road under the water”
文摘Siberian taimen Hucho taimen(Pallas,1773)is a broadly distributed and popular sport fish with high economic value.However,low abundance and hard-to-reach habitat make the Siberian taimen a relatively understudied species.Here we describe the morphological variability of two size groups of Siberian taimen juveniles from the eastern(Amur River basin)and western(Kama River basin)parts of the species distribution.The largest morphological differentiation of Siberian taimen juveniles was observed at the inter-basin level.In the Amur River basin,Siberian taimen juveniles also differed morphologically even at sites located at a distance of 20 km from each other,which may be explained by a small home-range inhabitation of juveniles leading to the formation of their morphotype determined by local environmental conditions.The pattern of allometry varies in taimen from different rivers,which could be related to the ontogenetic shift of ecological niches and the level of heterogeneity of the river environment.
基金Supported by the National Natural Science Foundation of China(Nos.52209048,52109083)the Hunan Provincial Natural Science Foundation(Nos.2024JJ5207,2021JJ40100)+1 种基金the Special Fund for Building Chenzhou National Sustainable Development Agenda Innovation Demonstration Zone in Hunan Province(No.2022sfq51)the China National University Student Innovation&Entrepreneurship Development Program(No.S202310536023)。
文摘In recent years,microplastics(MPs)in freshwater lake have been receiving increasing attention;however,the microbial communities on the surface of MPs have not been well studied.To investigate the potential risk posed by MPs to the lake ecosystem and its surface microbial community structure,MPs samples were collected in September 2023 in the freshwater Dongting Lake,Hunan,China,at five sites,and the differences in bacterial species community composition and structure between MPs and water samples were analyzed.Results show that MPs(13.71±3.32 items/L)in the samples were mostly black in color,fiber in shape,and PES in composition,and those<0.5 mm in size are dominant.The bacterial composition in water was different from that on MPs.At phylum level,Proteobacteria,Actinobacteria,Cyanobacteria,and Bacteroidetes were dominated in relative abundance in both water and MPs.Proteobacteria was more abundant in MPs than in water.The relative abundance of Bacteroidota and Actinobacteriota was significantly lower in MPs than in water.At genus level,Pantoea and Pseudomonas were potentially pathogenic genera in MPs surfaces.The presence of Cyanobacteria and pathogenic bacteria is undoubtedly a potential risk to the deterioration of the water quality.This study revealed the difference in the distribution of bacterial community in water and MPs in Dongting Lake and provided new perspectives to further understanding of MPs pollution in freshwater lakes.
基金supported by the National Natural Science Foundation of China(Nos.51839011,42203079,and U2240208)the Carbon Peak/Neutralization Technology Innovation Project of Jiangsu Province,China(No.BK20220043)the Excellent Postdoctoral Project of Jiangsu Province,China(No.2022ZB452).
文摘Biological nitrogen fixation(BNF)is a crucial process that provides bioavailable nitrogen and supports primary production in freshwater lake ecosystems.However,the characteristics of diazotrophic community and nitrogenase activity in freshwater lake sediments remain poorly understood.Here,we investigated the diazotrophic communities and nitrogenase activities in the sediments of three large river-connected freshwater lakes in eastern China using 15N-isotope tracing and nifH sequencing.The sediments in these lakes contained diverse nitrogenase genes that were phylogenetically grouped into Clusters I and III.The diazotrophic communities in the sedimentswere dominated by stochastic processes in Hongze Lake and Taihu Lake,which had heterogeneous habitats and shallower water depths,while in Poyang Lake,which had deeper water and a shorter hydraulic retention time,the assembly of the diazotrophic community in the sediments was dominated by homogeneous selection processes.Temperature and water depth were also found the key environmental factors affecting the sediment diazotrophic communities.Sediment nitrogenase activities varied in the three lakes and within distinct regions of an individual lake,ranging from 0 to 14.58 nmol/(kg·hr).Nitrogenase activity was significantly correlated with ferric iron,total phosphorus,and organic matter contents.Our results suggested that freshwater lake sediment contain high diversity of nitrogen-fixing microorganisms with potential metabolic diversity,and the community assembly patterns and nitrogenase activities varied with the lake habitat.
基金Supported by the National Natural Science Foundation of China(No.31600325)the Self-determined Research Funds of the Central China Normal University(CCNU)from the Colleges’Basic Research and Operation of MOE(No.CCNU20TS022)。
文摘To assess the population development of submerged plant species in disturbed lake ecosystems,we need to better understand the genetic diversity and spatial genetic structure at a fine scale,as well as the impact of disturbances on the populations.Caohai Lake,in southwest China,is a suitable natural sampling lake because of its abundance of submerged plants and the intense human disturbance.Three widely distributed species,Potamogeton lucens,Ceratophyllum demersum,and Myriophyllum spicatum,were sampled;the spatial position of each individual was recorded in two-dimensional coordinates;and the species were analyzed genetically using microsatellite markers.Among the species studied,M.spicatum exhibited the highest genetic and clonal diversities.All P.lucens subpopulations but one showed a significant fine-scale spatial genetic structure(FSGS),which may result from the limited gene dispersal.However,M.spicatum and C.demersum,with a relatively large distance of gene dispersal,had no significant FSGS.The FSGS pattern of P.lucens at the dock site with intense boat disturbance was significantly different from that at other sites.Our results imply that the FSGS of submerged plants is affected by many factors including seed dispersal,vegetative reproduction and disturbance from birds and boats.Most subpopulations of the three species hadσ_(sex)^(2)/σ_(veg)^(2)values greater than one,implying that the sexual dispersal contributes more than vegetative dispersal to total gene dispersal.Therefore,it is worth paying attention to the importance of seed dispersal for population development of submerged plants in lake ecosystems.
基金supported by the National Natural Science Foundation of China(Projects 42090022)。
文摘Whether clay-rich shale reservoirs with low-medium maturity can serve as primary exploration targets remains a focal point of debate in the academic community.Clarifying the exploration potential of clayrich shale reservoirs is crucial for the future exploration and development of lacustrine shale.The Triassic Yanchang Formation in the Ordos Basin has been one of most productive lacustrine shale oil systems in China,with substantial oil production capacity already established.While the primary productive layers are currently fine-grained siltstone interbeds,however,it remains a highly debated issue whether the volumetrically more significant clay-rich reservoirs can become viable exploration targets in the near future.To address this issue,we examined the exploration potential of different lithofacies assemblages in Member 7(Mbr 7)of the Triassic Yanchang Formation,using a borehole in the Tongchuan area of the southern Ordos Basin as an example.We identified favorable exploration targets and assessed whether clay-rich reservoirs formed predominantly-freshwater conditions can become viable exploration targets.The results indicate the presence of six lithofacies in clay-rich reservoirs of Mbr 7 of the Yanchang Formation,with two main lithofacies assemblages:laminated organic-rich shale and massive mudstone.From the perspective of sandstone distribution,the sandstone interlayers within laminated organic-rich shale are primarily formed by gravity(hyperpycnal)flows,while sandstones deposited in delta front environments are typically associated with massive mudstone.Laminated organic-rich shale deposition occurred in an anoxic,deep-water environment characterized by high primary productivity,whereas massive mudstone formed in environments with high sedimentation rates and substantial terrigenous debris influx.Currently,the exploration potential of sandstone interlayers exceeds that of clay-rich reservoirs,with the greatest potential observed in the sandstone interlayers associated with laminated organic-rich shale formed by gravity(hyperpycnal)flows.Comparative analysis reveals that clay-rich reservoirs with low to medium maturity present great challenges for exploitation,making interlayer-type reservoirs the main focus of exploration at this stage.Nevertheless,clay-rich reservoirs in closed systems with high thermal maturity and organic matter content also hold considerable potential.
文摘Donghua University develops novel photothermal fabric to address freshwater crisis 2D photothermal membranes have demonstrated numerous advantages in solar desalination due to their flexibility,scalability,and low cost.However,their practical applications are limited by the restricted evaporation area and obstructed vapor channels.The research team led by Chen Zhigang,a researcher from the State Key Laboratory of Advanced Fiber Materials and the School of Materials Science and Engineering at Donghua University,has designed a novel biomimetic photothermal fabric,which is composed of two carbon-nanotube-hydrogel-coated polyester(PET)fabrics separated by fiber pillars,with the upper fabric layer having a hole array as stomatal channels.This fabric shows high solar-absorption efficiency(96.1%)and decreased water-evaporation enthalpy(1664.6 kJ kg^(-1)).
基金supported by Alberta Health,Alberta Innovates,the Canada Research Chairs Program,the Canadian Institutes of Health Research,and the Natural Sciences and Engineering Research Council of Canada。
文摘Arsenic speciation in freshwater fish is crucial for providing meaningful consumption guidelines that allow the public to make informed decisions regarding its consumption.While marine fish have attractedmuch research interest due to their higher arsenic content,research on freshwater fish is limited due to the challenges in quantifying and identifying arsenic species present at trace levels.We describe here a sensitivemethod and its application to the quantification of arsenic species in freshwater fish.Arsenic species from fish tissues were extracted using a methanol/water mixture(1:1 vol.ratio)and ultrasound sonication.Anion-exchange high-performance liquid chromatography(HPLC)enabled separation of arsenobetaine(AsB),inorganic arsenite(iAs^(Ⅲ)),dimethylarsinic acid(DMA),monomethylarsonic acid(MMA),inorganic arsenate(iAs^(Ⅴ)),and three new arsenic species.Inductively coupled plasma mass spectrometry(ICPMS)provided highly sensitive and specific detection of arsenic.A limit of detection of 0.25μg/kg(wet weight fish tissue)was achieved for the five target arsenic species:AsB,iAs^(Ⅲ),DMA,MMA,and iAs^(Ⅴ).A series of experimentswere conducted to ensure the accuracy and validity of the analytical method.The method was successfully applied to the determination of arsenic species in lakewhitefish,northern pike,and walleye,with AsB,DMA,and iAs^(Ⅴ) being frequently detected.Three new arsenic species were detected,but their chromatographic retention times did not match with those of any available arsenic standards.Future research is necessary to elucidate the identity of these new arsenic species detected in freshwater fish.
基金funded by the National Key Research and Development Program of China(2022YFB3803600)the National Natural Science Foundation of China(22368050,22378346)+4 种基金the Key Research and Development Program of Yunnan Province(202302AF080002)Yunnan Basic Applied Research Project(202401AT070460,202401AU070229)Xingdian Talent Support Program Project in Yunnan Province,the Scientific Research Fund Project of Yunnan Education Department(2024J0014,2024J0013)the Open Project of Yunnan Precious Metals Laboratory Co.,Ltd(YPML-2023050259,YPML-2023050260,YPML-20240502008)the Scientific Research and Innovation Project of Postgraduate Students in the Academic Degree of Yunnan University.
文摘The reasonable development and design of high-efficiency and low-cost electrocatalysts for hydrogen evolution reaction(HER)under industrial current densities are imperative for achieving carbon neutrality,while also posing challenges.In this study,an efficient electrocatalyst is successfully constructed through electrodeposition methods,which consists of monodispersed Pt loaded on amorphous/crystalline nickel–iron layered double hydroxide(Pt-SAs/ac-NiFe LDH).The Pt-SAs/ac-NiFe LDH demonstrates an elevated mass activity of 17.66 A mg_(Pt)^(−1)and a significant turnover frequency of 17.90 s^(−1)for HER in alkaline conditions under the overpotential of 100 mV.Meanwhile,for alkaline freshwater and seawater,Pt-SAs/ac-NiFe LDH exhibits ultra-low overpotentials of 141 and 138 mV to reach 1000 mA cm^(−2),respectively.Remarkably,it maintains stable operation for 100 h at 500 mA cm^(−2),showcasing its robustness and reliability.In situ Raman spectra reveal that Pt single atoms(Pt-SAs)accelerate interfacial water dissociation,thereby enhancing the HER kinetics in Pt-SAs/ac-NiFe LDH.Furthermore,theoretical calculation results show significant electronic interaction between the Pt-SAs and the ac-NiFe LDH support.The interaction significantly enhances water adsorption and dissociation,and balances the adsorption/desorption of hydrogen intermediates,ultimately improving HER performance.This research provides a viable method for designing efficient HER catalysts for water electrolysis in alkaline freshwater and seawater under industrial current densities.
基金Supported by National Natural Science Foundation of China (40801227)Foundation of Key Laboratory of Aquatic Genetic Resources and Aquacul-tural Ecology,Ministry of Agriculture (KFT2006-7)~~
文摘[Objective] The aim was to establish the water quality evaluation index system for freshwater aquaculture pond.[Method] The expert survey,DELPHI,field research and other methods were used.Based on the analysis of factors influencing water quality of freshwater aquaculture pond,and the importance degree of 14 factors influencing water quality of freshwater aquaculture pond was ordered.Then,five factors were selected as index to establish the water quality evaluation index system of freshwater aquaculture with the determination for thresholds of these factors.[Result] The importance degree of water quality of freshwater aquaculture pond showed an order of Dissolved oxygenpHPhytoplankton biomassSecchi depthTotal NitrogenZooplankton biomassWater temperatureBiochemical Oxygen DemandWater colorSalinityTotal hardness;according to the value of importance degree,the dissolved oxygen,pH,secchi depth,phytoplankton biomass and total nitrogen these five factors were selected as the index system of water quality evaluation of pond.The level of water quality of freshwater aquaculture pond was divided into five,and the tolerance range of fish to each index was obtained by expert observation.[Conclusion] This study had provided a scientific basis for water quality evaluation system of freshwater aquaculture pond.
基金Supported by Special Fund for the Construction of Modern Agricultural Industry Technology System(CARS-46)Special Fund for Basic Research and Operating Expenses of Central-level Research Institutes(2007JBFA03)~~
文摘The establishment of water circulation aquaculture system realized the hi- erarchical use of nitrogen, phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource. However, no research has been reported on the detailed calculation of the relationship between the area of aquaculture pond and purification pond. In this study, referring to the absorption ability of aquatic plants to pollutants in aquaculture wastewater and pollutant generation and discharge coefficient in aquaculture pond, based on the general rules of water quality management in freshwater aquaculture system, a calculation mode was es- tablished to investigate the relationship between the area of aquaculture pond and purification pond in freshwater recirculation aquaculture system, which was feasible to explain related cases and would provide theoretical basis to reduce the economic costs in the construction of water circulation aquaculture system and realize the bal- ance between the ecological benefits and the economic benefits.
