Freshwater ecosystems are crucial in the global emissions of greenhouse gases(GHGs)such as CH_(4).Macrophytes are the main organic matter(i.e.,detritus)supplier to the sediment of these systems,thus controlling CH_(4)...Freshwater ecosystems are crucial in the global emissions of greenhouse gases(GHGs)such as CH_(4).Macrophytes are the main organic matter(i.e.,detritus)supplier to the sediment of these systems,thus controlling CH_(4) production.However,species-specific differences(structure and composition)may determine contrasting patterns of detritus transformation into CH_(4).Furthermore,eutrophication can affect the degradation and,consequently,CH_(4) production.We performed a 64-day microcosm experiment with anoxic incubations of detritus from seven phylogenetically different macrophytes(two charophytes,filamentous algae–Spirogyra,Cladophora–,three submerged plants and an amphibious one),under two trophic conditions(oligo-versus eutrophic)and with/without sediment.We assessed the CH_(4) and CO_(2) production and the changes in the detritus quality at the end of the experiment.The ranking in the mean cumulative CH_(4) production was:Chara hispida>Nitella hyalina>Najasmarina≈Teucrium scordium>Stuckenia pectinata≈Myriophyllum spicatum>filamentous algae,and it was related to the detritus quality.GHGs maximumproduction rates were 1.6(N.marina)-1.2(C.hispida)mmol CH_(4)/(g OC·day)and 1.7(N.marina)-1.5(C.hispida)mmol CO_(2)/(g OC·day).The CO_(2):CH_(4) ratiowas biased towards CO_(2) during the first 10 days(average ratio of 200)and fell afterwards to about 1 for all macrophyte species and treatments.The sediment favored detritus decomposition(probably due to the“positive priming effect”),increasing GHGs production.The influence of nutrient enrichment was not evident.Delving into themacrophyte detritus quality-GHGs production relationship is needed to forecast the GHGs emissions in macrophyte-dominated systems.展开更多
Marine algae and shellfish are contributing positively to carbon sinks.As the world’s largest algae and shellfish producer,the carbon sinks potential in China is crucial.Here,the situation of algae and shellfish cult...Marine algae and shellfish are contributing positively to carbon sinks.As the world’s largest algae and shellfish producer,the carbon sinks potential in China is crucial.Here,the situation of algae and shellfish cultivation in China’s offshore from 2011 to 2020 was elaborated.The intensity of carbon sequestration by algae and shellfish annually was estimated.In 2020,the production of algae and shellfish in China has already reached to 2.62 million tons and 14.8 million tons,with an annual growth rate of 7.03%and 3.14%,respectively.Their annual productivity also maintained an increasing trend,while the rate of productivity increase decreased over ten years except for Porphyra haitanensis,Sinonovacula constricta,and Haliotis discus hannai.Crassostrea gigas and Rudi-tapes philippinarum were the highest fixed carbon shellfish,and Saccharina japonica was the dominant algae.Meanwhile,the rela-tively high carbon sink intensity was found in Shandong,Fujian,and Liaoning.In the last decade,the total carbon sink of algae and shellfish was 1.62 million tons and 7.16 million tons,with an increase of 90.55%and 31.73%,respectively.This created an economic value of 3.293 billion dollars.Results indicated that China’s offshore mariculture algae and shellfish assumed the considerable car-bon sink capacity.Through rational utilization of the carbon sink resources in algae and shellfish,it provides potential ideas for Chi-na to pursue personalized carbon neutrality.展开更多
Using phosphorus(P)fertilizers has historically increased agricultural productivity,yet the highly dissipative nature of phosphate rock and the low effciency due to soil fxation and runoff raise sustainability concern...Using phosphorus(P)fertilizers has historically increased agricultural productivity,yet the highly dissipative nature of phosphate rock and the low effciency due to soil fxation and runoff raise sustainability concerns.Algae fertilizers have emerged as a promising eco-friendly alternative.However,the potential of algae fertilizers for providing sustained P availability and their impacts on plant growth,soil microbes,and nutrient cycling remains to be explored.In this study,we developed a polyphosphate-enriched algae fertilizer(PEA)and conducted comparative experiments with chemical P fertilizers(CP)through soil and solution cultures,as well as crop growth trials.Soil cultivation experiments showed that PEA released twice as much labile P as initially available in the soil,and it functioned as a slow-release P source.In contrast,soils treated with CP initially exhibited high levels of labile P,which was gradually converted to stable forms,but it dropped to 30%of the labile P level in PEA after three months.Further tests revealed that the slow release of P from PEA was linked to increased microbial activity,and the microbial biomass P(MBP)content was about eight times higher than in soils treated with CP after three months,resulting in a 75%decline in the microbial biomass carbon(MBC)to MBP ratio.Microbial diversity analysis showed that algae fertilizers could recruit more benefcial microbes than CP,like phosphorus-solubilizing bacteria,plant growth-promoting bacteria,and stress-resistant bacteria.Crop pot experiments,along with amplicon and metagenomic analysis of tomato root-associated microbes,revealed that algae fertilizers including PEA promoted plant growth comparable to CP,and enhanced soil P cycling and overall nutrient dynamics.These data showed that algae fertilizers,especially PEA,can stabilize soil P fertility and stimulate plant growth through their slow P release and the recruitment of benefcial microbes.Our study highlights the potential of PEA to foster sustainable agriculture by mitigating the P scarcity and soil P loss associated with chemical fertilizers and improving plant growth and soil health.展开更多
The adhesion of Shewanella algae(S.algae)on the surface of stainless steel induced the formation and coverage of calcium carbonate minerals in the aerobic environment,and the effect of these minerals on the passive fi...The adhesion of Shewanella algae(S.algae)on the surface of stainless steel induced the formation and coverage of calcium carbonate minerals in the aerobic environment,and the effect of these minerals on the passive film of stainless steel was investigated by focused ion beam-scanning electron microscopy/transmission electron microscopy(FIB-SEM/TEM)and electron energy loss spectroscopy(EELS)techniques.The TEM and energy-dispersive X-ray spectroscopy(EDS)results revealed that the passive film in the region covered by mineralized particles underwent chelation between Fe and Cr compounds with CaCO_(3),forming an unstable amorphous layer,which accelerated the loss of Fe and Cr elements.EELS analysis showed that the loss of Fe element in the passive film was the most significant,with a transition from Fe^(3+)to soluble Fe^(2+)occurring,which caused by the iron-reducing property and metabolic activities of the adherent S.algae.The loss of the main metal elements caused the accelerated degradation of the passive film beneath the minerals.展开更多
This study delves into biodiesel synthesis from non-edible oils and algae oil sources using Response Surface Methodology(RSM)and an Artificial Neural Network(ANN)model to optimize biodiesel yield.Blend of C.vulgaris a...This study delves into biodiesel synthesis from non-edible oils and algae oil sources using Response Surface Methodology(RSM)and an Artificial Neural Network(ANN)model to optimize biodiesel yield.Blend of C.vulgaris and Karanja oils is utilized,aiming to reduce free fatty acid content to 1%through single-step transesterification.Optimization reveals peak biodiesel yield conditions:1%catalyst quantity,91.47 min reaction time,56.86℃reaction temperature,and 8.46:1 methanol to oil molar ratio.The ANN model outperforms RSM in yield prediction accuracy.Environmental impact assessment yields an E-factor of 0.0251 at maximum yield,indicating responsible production with minimal waste.Economic analysis reveals significant cost savings:30%-50%reduction in raw material costs by using non-edible oils,10%-15%increase in production efficiency,20%reduction in catalyst costs,and 15%-20%savings in energy consumption.The optimized process reduces waste disposal costs by 10%-15%,enhancing overall economic viability.Overall,the widespread adoption of biodiesel offers economic,environmental,and social benefits to a diverse range of stakeholders,including farmers,producers,consumers,governments,environmental organizations,and the transportation industry.Collaboration among these stakeholders is essential for realizing the full potential of biodiesel as a sustainable energy solution.展开更多
Antarctic continental lakes and ponds are among the most impoverished aquatic environments on earth but many of them support flourishing populations of cyanobacteria,eukaryotic algae,protozoans,and some multicellular ...Antarctic continental lakes and ponds are among the most impoverished aquatic environments on earth but many of them support flourishing populations of cyanobacteria,eukaryotic algae,protozoans,and some multicellular animals.In this study,we present results of a microscopic analysis of cyanobacteria and eukaryotic algae from nine diverse types of Antarctic continental water bodies during one austral summer.The results supplement and enlarge our previous studies on the limnological characteristics of the epiglacial and supraglacial lakes and ponds in Dronning Maud Land,an area that has received little attention from limnologists.The taxon with highest frequency among the samples(n=79)was Mesotaenium cf.berggrenii,a eukaryotic Zygnematophyceae,which occurred in 82%of the samples with a maximum cell density of 68 cells·mL^(-1).The taxa with second and third highest frequency were the prokaryotes Gloeocapsopsis(60%)and Leptolyngbya(41%),followed by Chlamydomonas(34%)and Cyanothece(29%).The number of taxa varied between 7-21 among the lakes and ponds,being highest in a supraglacial lake,and lowest in an epiglacial lake.The results did not reveal any obvious correlation between the abundance of any taxa and the water chemistry,but water bodies with inorganic sediments had higher cell densities and biomasses than those without sediment.This suggests the importance of sediment in supporting biological diversity in these ultraoligotrophic lakes and ponds.展开更多
Phycoerythrin extracted from Antarctic red seaweeds shows promising characteristics to be applied as an anode sensitizer in water-splitting photoelectrochemical cells.Under light irradiation and using an LED lamp,the ...Phycoerythrin extracted from Antarctic red seaweeds shows promising characteristics to be applied as an anode sensitizer in water-splitting photoelectrochemical cells.Under light irradiation and using an LED lamp,the red-colored protein shows an interesting ability to profit the incident light,as confirmed by the presence of oxygen bubbles next to the electrode surface without applying any external potential.Our results showed that the addition of iodide is helpful to allow the regeneration of the dye;nevertheless,oxygen evolution is not favored.Thermodynamics analysis of the involved semi-reactions is also helpful to understand the observed results.The exploration of Antarctic resources offers then an alternative for the development of green energies,with a particular focus on their use as sensitizers to profit from the sunlight in water-splitting as well as in photovoltaic devices.展开更多
An in-vitro experiment was conducted to assess the interaction between biochar and algae on a problem soil. Experiments were performed with and without algae to observe the effectiveness of algae for overcoming the ch...An in-vitro experiment was conducted to assess the interaction between biochar and algae on a problem soil. Experiments were performed with and without algae to observe the effectiveness of algae for overcoming the challenges posed by problem soils. At the end of incubation periods, the adsorption and desorption of phosphorus (P) on a problem soil vis-á-vis algal inoculation were determined. Our results showed that different types of biochars adsorbed different amounts of P suggesting that the source of biochar played a crucial role in determining its behavior towards P. Tannery waste biochar significantly adsorbed 147% and 35% more P compared to that of the chicken litter and orange peel biochars respectively. Significant reductions in adsorption were observed when the biochar was used in combination with the algae which could be due to the beneficial effects of algae leading to the amelioration of the problem soil. Adsorption was reduced to 34%, 24% and 20% for the orange peel biochar + algae, chicken litter biochar + algae and tannery waste biochar + algae, respectively compared to the corresponding biochars present as a single solid. Phosphorus (P) desorption was also reduced significantly in presence of algal inoculation. Overall our findings suggest that the application of algae along with biochar in the problem soil could reduce the adsorption of P which would influence the availability of P.展开更多
With the proceeding of global warming and water eutrophication,the phenomenon of green tide has garnered significant societal interest.Consequently,researchers had increasingly focused on the potential applications of...With the proceeding of global warming and water eutrophication,the phenomenon of green tide has garnered significant societal interest.Consequently,researchers had increasingly focused on the potential applications of green algae biomass,particularly its polysaccharides.The polysaccharide serves as the primary active constituent of green algae and has demonstrated numerous advantageous biological activities,including antioxidant,antiviral,anticoagulant,hypolipidemic and immuno-modulatory activities.The favorable bioavailability and solubility of green algae oligosaccharides are attributed to their low molecular weight.So there has been a growing interest in researching green algae polysaccharides and oligosaccharides for the utilization of marine biological resources.This review summarized the extraction,purification,chemical structure,composition,biological activity,and potential applications prospect of polysaccharides and oligosaccharides derived from green algae.The review could be helpful for expanding the applications of polysaccharides and oligosaccharides of green algae.展开更多
In the paper, under the framework of exploring the interaction between algae and bacteria, an algae-bacteria ecological model was established to analyze the interaction mechanism and growth coexistence mode between al...In the paper, under the framework of exploring the interaction between algae and bacteria, an algae-bacteria ecological model was established to analyze the interaction mechanism and growth coexistence mode between algicidal bacteria and algae. Firstly, mathematical work mainly provided some threshold conditions to ensure the occurrence of transcritical bifurcation and saddle-node bifurcation, which could provide certain theoretical support for selecting key ecological environmental factors and numerical simulations. Secondly, the numerical simulation work dynamically displayed the evolution process of the bifurcation dynamic behavior of the model (2.1) and the growth coexistence mode of algae and algicidal bacteria. Finally, it was worth summarizing that intrinsic growth rate and combined capture effort of algae population had a strong influence on the dynamic behavior of the model (2.1). Furthermore, it must also be noted that transcritical bifurcation and saddle-node bifurcation were the inherent driving forces behind the formation of steady-state growth coexistence mode between algicidal bacteria and algae. In summary, it was hoped that the results of this study would contribute to accelerating the study of the interaction mechanism between algicidal bacteria and algae.展开更多
Bisphenol A (BPA) is the primary chemical used in the production of epoxy resins but as of today is not widely available in a bio-based form. BPA is also classified as a substance of very high concern due to its repro...Bisphenol A (BPA) is the primary chemical used in the production of epoxy resins but as of today is not widely available in a bio-based form. BPA is also classified as a substance of very high concern due to its reproductive toxicity and endocrine-disrupting effects. Phlorotannins, a type of polyphenols, offer a promising structural alternative to bisphenol A as a more sustainable option. They are found in high quantities in brown algae, which are already harvested for alginate production. As a result, phlorotannins present an under-researched yet promising marine resource for the chemical industry, particularly in the area of epoxy resin formulation. In this study, a model epoxy resin compound based on phloroglucinol, the simplest phlorotannin, was chosen to explore its reactivity and the thermo-mechanical properties of epoxy resins based thereof. As hardeners well-established systems like isophorone diamine for ambient temperature cure as well as heat-curing anhydrides and dicyandiamide were used. Across all cases, thermosets with glass transition temperatures above 100?C were achieved under cross-linking conditions similar to those used today. One phthalic anhydride derivative yielded a glass transition temperature of 198?C, highlighting the significant potential of these algae-based epoxy resins for industrial uses, such as impregnating resins for fiber-reinforced plastics.展开更多
By mild PAGE method, 11, 11, 7 and 9 chlorophyll_protein complexes were isolated from two species of siphonous green algae (Codium fragile (Sur.) Hariot and Bryopsis corticulans Setch.), green alga (Ulothrix flacca (D...By mild PAGE method, 11, 11, 7 and 9 chlorophyll_protein complexes were isolated from two species of siphonous green algae (Codium fragile (Sur.) Hariot and Bryopsis corticulans Setch.), green alga (Ulothrix flacca (Dillw.) Thur.), and spinach (Spinacia oleracea Mill.), respectively. Apparent molecular weights, Chl a/b ratios, distribution of chlorophyll, absorption spectra, low temperature fluorescence spectra of these complexes were determined, and compared with one another. PSⅠ complexes of two siphonous green algae are larger in apparent molecular weight because of the attachment of relative highly aggregated LHCⅠ. Four isolated light_harvesting complexes of PSⅡ are all siphonaxanthin_Chl a/b_protein complexes, and they are not monomers and oligomers like those in higher plants. Especially, the absence of 730 nm fluorescence in PSⅠ complexes indicates a distinct structure and energy transfer pattern.展开更多
[Objective] The biological characteristics and pathogenicities of Shewanella algae and Shewanella abalone from Babylonia were studied in this paper. [Method]The hemolytic bacteria were isolated from the hepatopancreas...[Objective] The biological characteristics and pathogenicities of Shewanella algae and Shewanella abalone from Babylonia were studied in this paper. [Method]The hemolytic bacteria were isolated from the hepatopancreas of Babylonia suffered from proboscis edema with blood agar plate. The dominant bacterial community in the ill Babylonia was identified by 16 S r DNA sequence analysis, and the bacterial cultural and biochemical characteristics and pathogenicities were studied. [Result]The Shewanella bacteria, including Shewanella algae and Shewanella abalone, are the dominant bacterial community in Babylonia suffered from proboscis edema.The colony characteristics of Shewanella algae in nutrient agar medium, TCBS agar medium and CHROMagar vibrio colored medium were similar to those of Shewanella abalone. Shewanella algae possessed β-hemolysis and Shewanella abalone possessed α-hemolysis in the blood agar plate. The biochemical reaction of Shewanella algae and Shewanella abalone was all of non-fermentation type. The results of artificial infection test showed that half lethal dose(LD50) of the test strains of Shewanella algae was 10-5.50/0.1 ml. The test strains of Shewanella algae have strong toxicity, and could cause mice and chickens to die of sepsis with mortality of100%. The mortality of Babylonia infected with Shewanella algae was 10%; while the survived Babylonia lost the ability of moving and intaking for a long time, but they were not suffered from proboscis edema. There was no death in mice or chicks infected with Shewanella abalone, but their livers and spleens were slightly hyperemic and swelling. There was also no death in Babylonia infected with Shewanella abalone, but their intaking and moving ability was lost for a short time.[Conclusion] Although Shewanella algae and Shewanella abalone were the dominant bacteria in Babylonia suffered from proboscis edema, they were not the main pathogenic bacteria for proboscis edema. Shewanella algae had strong pathogenicity to mice, chicks and Babylonia, while Shewanella abalone showed no marked pathogenicity to those experimental animals in this study.展开更多
In order to better monitor N and P pollutants, heavy metals, pesticides and other organic pollutants in water areas, we researched sensitivity and tolerance of aquatic algae on water environment and effects of the pol...In order to better monitor N and P pollutants, heavy metals, pesticides and other organic pollutants in water areas, we researched sensitivity and tolerance of aquatic algae on water environment and effects of the pollutants on algae population, analyzing toxin and enrichment of pollutants on algae. The results indicated that aquatic alga is a better indicator for some pollutants in water, for which water contamination can be surveyed and analyzed rapidly.展开更多
To understand the spatial and temporal variation characteristics of blue algae in summer in Lake Dianshan,the phytoplankton in Lake Dianshan from June to September in 2009 was surveyed. It found 11 genera and 28 speci...To understand the spatial and temporal variation characteristics of blue algae in summer in Lake Dianshan,the phytoplankton in Lake Dianshan from June to September in 2009 was surveyed. It found 11 genera and 28 species blue algae in total. Microcystis,Oscillatoria and Chroococcus were the main composition communities of blue algae in Lake Dianshan in summer. In the survey period,the average density of blue algae in Lake Dianshan was 16.48×106 cells/L which changed during 1.01×106-59.76×106 cells/L. The characteristics were:September > July > August > June. The mass propagation and aggregation of Microcystis in September caused that the water blooms phenomenon in the partial water areas was serious. In the space,the average density of blue algae in the west and southwest parts of Lake Dianshan was bigger than in the east and southeast. When the nutritive matter was sufficient,the temperature was the main factor which affected the generation and disappearance of blue algae water blooms. The wind direction was also an important factor which affected the distribution of blue algae.展开更多
[Objective] The research aimed to know the ecological environment pollution characteristics of Hongfeng Lake water area and the evolution rule,which provided the theory basis for improving the water quality condition....[Objective] The research aimed to know the ecological environment pollution characteristics of Hongfeng Lake water area and the evolution rule,which provided the theory basis for improving the water quality condition.[Method] Based on the investigation and research of indoor and outdoor,the water quality,aquatic ecosystem,pollution characteristic of sediment and occurrence law of algae blooms in Hongfeng Lake were comprehensively analyzed by combining with the relevant literatures.[Result] Hongfeng Lake was in moderate-heavy eutrophication situation,and the water quality was V-bad V class.The sediment accumulated a lot of nutrient salt,which was the important pollution source of eutrophication in Hongfeng Lake Reservoir.The aquatic ecosystem degraded,and it was easy to form the algae blooms.[Conclusion] The pollution treatment of Hongfeng Lake was extremely urgent.展开更多
Microcystins (MCYSTs) isolated from blue-green algae,are hepatotoxic polypeptides.It will induce severe intrahepatic hemorrhage and liver necrosis at low concentrations in rats and mice.MCYST- LR is one of MCYSTs whic...Microcystins (MCYSTs) isolated from blue-green algae,are hepatotoxic polypeptides.It will induce severe intrahepatic hemorrhage and liver necrosis at low concentrations in rats and mice.MCYST- LR is one of MCYSTs which consists of 2 variable L- amino acids(leucine and arginine),3 D-amino acids and 2 unusualamino acids(including Adda).MCYSTs bind to protein phosphatase 1 and 2A,and strongly inhibit their activities.The resultant increase of phosphoprotein was referred to be involved in tumor-promoting activity in liver.According to the above results and animal study,MCYST-LR is a potent liver tumor promoter.There were 9 positive from 30 samples of pond-ditch water in high endemic county-Haimen by high-peformance liquid chromatograph and 3 already confirmed by liquid chromograph/mass spectrometer.The quantities of MCYSTs were different between drinking water of liver cancer cases and controls groups.122±0.057and 0.072±0.044μg/200ml respectively) by ELISA. It is not easy to remove by conventional water treatment procedures.The relationship between MCYSTs and oncogenes and anti-oncogenes are under studying.展开更多
[Objective] The research aimed to improve the method of isolation of algae.[Method] The samples were cultured in liquid medium after pre-culture in natural medium.[Result]12 species of algae were isolated from the sam...[Objective] The research aimed to improve the method of isolation of algae.[Method] The samples were cultured in liquid medium after pre-culture in natural medium.[Result]12 species of algae were isolated from the sample.[Conclusion] The method is useful and easy to be handled.展开更多
Algae have become an area of intensive research in many fields of study. Areas of application are becoming increasingly diverse with the advent of technologies particularly in the mass production of algae biomass. Alg...Algae have become an area of intensive research in many fields of study. Areas of application are becoming increasingly diverse with the advent of technologies particularly in the mass production of algae biomass. Algae contain complex bioactive compounds and these are gaining importance in emerging technologies with nutritional and environmental applications. In this study, a preliminary investigation evaluated 15 species of algae from the major categories of marine and fresh water algae for their potential as inclusions in ruminant diets for management of greenhouse gas emissions. It was hypothesized that algae would positively affect rumen fermentation and gas production while reducing methane production. The hypothesis was tested using an Ankom automated gas monitoring system and rumen fluid from Bos indicus steers fed tropical forage diets. The results were variable between algae species with some showing a significant reduction in total gas and methane production, with others increasing gas and fermentation. The red and brown algae stand out as having potential for greenhouse gas mitigation with the brown alga Cystoseira having the most prominent effect. The effects observed on fermentation may be manipulated through dosage management and beneficial effects could be potentially maximized by preparing combinations of algal supplements. It has been demonstrated in this study that algae have the potential to assist in rumen fermentation management for improved gas production, and greenhouse gas abatement.展开更多
Based on the data of 18 cases during the past 30 years from 1978 to 2007,the major meteorological conditions for outbreak of blue-green alga in Hongze Lake were analyzed.The results showed that the main meteorological...Based on the data of 18 cases during the past 30 years from 1978 to 2007,the major meteorological conditions for outbreak of blue-green alga in Hongze Lake were analyzed.The results showed that the main meteorological conditions that affected the production and outbreak of blue-green alga were unusual high monthly average temperature,less precipitation and more sunshine hours in ten days.Through the selection of 1 or 0 factors on the values of above meteorological conditions over the years,if the conditions were accorded with the outbreak of blue-green alga,the factor was signed as 1,or it would be signed as 0;if there was outbreak of blue-green alga within ten days,it was signed as 1,or it would be signed as 0;crossing interrelated and integrated prediction method was adopted to establish the prediction equation for outbreak of blue-green alga,the historical fitting rate was 87.5%,and the predicting accuracy rate in 2008-2009 was 87.5%.In addition to meteorological conditions,outbreak of blue-green alga was also influenced by industrial pollutions,etc.,which should be considered in the forecasting procedures.展开更多
基金supported by Spanish Ministry of Science and Innovation (No.PID2020–116147GB-C22)funded by the European Union (Next Generation UE)+1 种基金funded by the Programa de Posgrado en Ciencias del Mar y Limnología (UNAM)CONAHCYT (CVU:828722).
文摘Freshwater ecosystems are crucial in the global emissions of greenhouse gases(GHGs)such as CH_(4).Macrophytes are the main organic matter(i.e.,detritus)supplier to the sediment of these systems,thus controlling CH_(4) production.However,species-specific differences(structure and composition)may determine contrasting patterns of detritus transformation into CH_(4).Furthermore,eutrophication can affect the degradation and,consequently,CH_(4) production.We performed a 64-day microcosm experiment with anoxic incubations of detritus from seven phylogenetically different macrophytes(two charophytes,filamentous algae–Spirogyra,Cladophora–,three submerged plants and an amphibious one),under two trophic conditions(oligo-versus eutrophic)and with/without sediment.We assessed the CH_(4) and CO_(2) production and the changes in the detritus quality at the end of the experiment.The ranking in the mean cumulative CH_(4) production was:Chara hispida>Nitella hyalina>Najasmarina≈Teucrium scordium>Stuckenia pectinata≈Myriophyllum spicatum>filamentous algae,and it was related to the detritus quality.GHGs maximumproduction rates were 1.6(N.marina)-1.2(C.hispida)mmol CH_(4)/(g OC·day)and 1.7(N.marina)-1.5(C.hispida)mmol CO_(2)/(g OC·day).The CO_(2):CH_(4) ratiowas biased towards CO_(2) during the first 10 days(average ratio of 200)and fell afterwards to about 1 for all macrophyte species and treatments.The sediment favored detritus decomposition(probably due to the“positive priming effect”),increasing GHGs production.The influence of nutrient enrichment was not evident.Delving into themacrophyte detritus quality-GHGs production relationship is needed to forecast the GHGs emissions in macrophyte-dominated systems.
基金funded by the Social Science Research Project of Fujian Provincial Department of Education(No.JAT22073)the Fujian‘Young Eagle Program’Youth Top Talent Program.
文摘Marine algae and shellfish are contributing positively to carbon sinks.As the world’s largest algae and shellfish producer,the carbon sinks potential in China is crucial.Here,the situation of algae and shellfish cultivation in China’s offshore from 2011 to 2020 was elaborated.The intensity of carbon sequestration by algae and shellfish annually was estimated.In 2020,the production of algae and shellfish in China has already reached to 2.62 million tons and 14.8 million tons,with an annual growth rate of 7.03%and 3.14%,respectively.Their annual productivity also maintained an increasing trend,while the rate of productivity increase decreased over ten years except for Porphyra haitanensis,Sinonovacula constricta,and Haliotis discus hannai.Crassostrea gigas and Rudi-tapes philippinarum were the highest fixed carbon shellfish,and Saccharina japonica was the dominant algae.Meanwhile,the rela-tively high carbon sink intensity was found in Shandong,Fujian,and Liaoning.In the last decade,the total carbon sink of algae and shellfish was 1.62 million tons and 7.16 million tons,with an increase of 90.55%and 31.73%,respectively.This created an economic value of 3.293 billion dollars.Results indicated that China’s offshore mariculture algae and shellfish assumed the considerable car-bon sink capacity.Through rational utilization of the carbon sink resources in algae and shellfish,it provides potential ideas for Chi-na to pursue personalized carbon neutrality.
基金supported by the National Key Research and Development Program of China(2021YFF1000404)the National Natural Science Foundation of China(32472823 and 32102478)+1 种基金the Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-CSAL-202301)the China Postdoctoral Science Foundation(2021M693447,2021M693449 and 2022T150707)。
文摘Using phosphorus(P)fertilizers has historically increased agricultural productivity,yet the highly dissipative nature of phosphate rock and the low effciency due to soil fxation and runoff raise sustainability concerns.Algae fertilizers have emerged as a promising eco-friendly alternative.However,the potential of algae fertilizers for providing sustained P availability and their impacts on plant growth,soil microbes,and nutrient cycling remains to be explored.In this study,we developed a polyphosphate-enriched algae fertilizer(PEA)and conducted comparative experiments with chemical P fertilizers(CP)through soil and solution cultures,as well as crop growth trials.Soil cultivation experiments showed that PEA released twice as much labile P as initially available in the soil,and it functioned as a slow-release P source.In contrast,soils treated with CP initially exhibited high levels of labile P,which was gradually converted to stable forms,but it dropped to 30%of the labile P level in PEA after three months.Further tests revealed that the slow release of P from PEA was linked to increased microbial activity,and the microbial biomass P(MBP)content was about eight times higher than in soils treated with CP after three months,resulting in a 75%decline in the microbial biomass carbon(MBC)to MBP ratio.Microbial diversity analysis showed that algae fertilizers could recruit more benefcial microbes than CP,like phosphorus-solubilizing bacteria,plant growth-promoting bacteria,and stress-resistant bacteria.Crop pot experiments,along with amplicon and metagenomic analysis of tomato root-associated microbes,revealed that algae fertilizers including PEA promoted plant growth comparable to CP,and enhanced soil P cycling and overall nutrient dynamics.These data showed that algae fertilizers,especially PEA,can stabilize soil P fertility and stimulate plant growth through their slow P release and the recruitment of benefcial microbes.Our study highlights the potential of PEA to foster sustainable agriculture by mitigating the P scarcity and soil P loss associated with chemical fertilizers and improving plant growth and soil health.
基金supported by the National Natural Science Foundation of China(52161160308)the Basic and Applied Basic Research Foundation of Guangdong Province(2021B1515130009)+1 种基金the China Postdoctoral Science Foundation(2022M720401)the Postdoctoral Fellowship Program of CPSF(GZC20240101).
文摘The adhesion of Shewanella algae(S.algae)on the surface of stainless steel induced the formation and coverage of calcium carbonate minerals in the aerobic environment,and the effect of these minerals on the passive film of stainless steel was investigated by focused ion beam-scanning electron microscopy/transmission electron microscopy(FIB-SEM/TEM)and electron energy loss spectroscopy(EELS)techniques.The TEM and energy-dispersive X-ray spectroscopy(EDS)results revealed that the passive film in the region covered by mineralized particles underwent chelation between Fe and Cr compounds with CaCO_(3),forming an unstable amorphous layer,which accelerated the loss of Fe and Cr elements.EELS analysis showed that the loss of Fe element in the passive film was the most significant,with a transition from Fe^(3+)to soluble Fe^(2+)occurring,which caused by the iron-reducing property and metabolic activities of the adherent S.algae.The loss of the main metal elements caused the accelerated degradation of the passive film beneath the minerals.
基金the financial support provided for this research project entitled“Enhancement of Cold Flow Properties of Waste Cooking Biodiesel and Diesel”under the File Number A/RD/RP-2/345 for the above publication.
文摘This study delves into biodiesel synthesis from non-edible oils and algae oil sources using Response Surface Methodology(RSM)and an Artificial Neural Network(ANN)model to optimize biodiesel yield.Blend of C.vulgaris and Karanja oils is utilized,aiming to reduce free fatty acid content to 1%through single-step transesterification.Optimization reveals peak biodiesel yield conditions:1%catalyst quantity,91.47 min reaction time,56.86℃reaction temperature,and 8.46:1 methanol to oil molar ratio.The ANN model outperforms RSM in yield prediction accuracy.Environmental impact assessment yields an E-factor of 0.0251 at maximum yield,indicating responsible production with minimal waste.Economic analysis reveals significant cost savings:30%-50%reduction in raw material costs by using non-edible oils,10%-15%increase in production efficiency,20%reduction in catalyst costs,and 15%-20%savings in energy consumption.The optimized process reduces waste disposal costs by 10%-15%,enhancing overall economic viability.Overall,the widespread adoption of biodiesel offers economic,environmental,and social benefits to a diverse range of stakeholders,including farmers,producers,consumers,governments,environmental organizations,and the transportation industry.Collaboration among these stakeholders is essential for realizing the full potential of biodiesel as a sustainable energy solution.
基金supported by AF-NSFC mobility program from the Academy of Finland(Grant no.333170)National Natural Science Foundation of China(Grant no.52211530038).
文摘Antarctic continental lakes and ponds are among the most impoverished aquatic environments on earth but many of them support flourishing populations of cyanobacteria,eukaryotic algae,protozoans,and some multicellular animals.In this study,we present results of a microscopic analysis of cyanobacteria and eukaryotic algae from nine diverse types of Antarctic continental water bodies during one austral summer.The results supplement and enlarge our previous studies on the limnological characteristics of the epiglacial and supraglacial lakes and ponds in Dronning Maud Land,an area that has received little attention from limnologists.The taxon with highest frequency among the samples(n=79)was Mesotaenium cf.berggrenii,a eukaryotic Zygnematophyceae,which occurred in 82%of the samples with a maximum cell density of 68 cells·mL^(-1).The taxa with second and third highest frequency were the prokaryotes Gloeocapsopsis(60%)and Leptolyngbya(41%),followed by Chlamydomonas(34%)and Cyanothece(29%).The number of taxa varied between 7-21 among the lakes and ponds,being highest in a supraglacial lake,and lowest in an epiglacial lake.The results did not reveal any obvious correlation between the abundance of any taxa and the water chemistry,but water bodies with inorganic sediments had higher cell densities and biomasses than those without sediment.This suggests the importance of sediment in supporting biological diversity in these ultraoligotrophic lakes and ponds.
文摘Phycoerythrin extracted from Antarctic red seaweeds shows promising characteristics to be applied as an anode sensitizer in water-splitting photoelectrochemical cells.Under light irradiation and using an LED lamp,the red-colored protein shows an interesting ability to profit the incident light,as confirmed by the presence of oxygen bubbles next to the electrode surface without applying any external potential.Our results showed that the addition of iodide is helpful to allow the regeneration of the dye;nevertheless,oxygen evolution is not favored.Thermodynamics analysis of the involved semi-reactions is also helpful to understand the observed results.The exploration of Antarctic resources offers then an alternative for the development of green energies,with a particular focus on their use as sensitizers to profit from the sunlight in water-splitting as well as in photovoltaic devices.
文摘An in-vitro experiment was conducted to assess the interaction between biochar and algae on a problem soil. Experiments were performed with and without algae to observe the effectiveness of algae for overcoming the challenges posed by problem soils. At the end of incubation periods, the adsorption and desorption of phosphorus (P) on a problem soil vis-á-vis algal inoculation were determined. Our results showed that different types of biochars adsorbed different amounts of P suggesting that the source of biochar played a crucial role in determining its behavior towards P. Tannery waste biochar significantly adsorbed 147% and 35% more P compared to that of the chicken litter and orange peel biochars respectively. Significant reductions in adsorption were observed when the biochar was used in combination with the algae which could be due to the beneficial effects of algae leading to the amelioration of the problem soil. Adsorption was reduced to 34%, 24% and 20% for the orange peel biochar + algae, chicken litter biochar + algae and tannery waste biochar + algae, respectively compared to the corresponding biochars present as a single solid. Phosphorus (P) desorption was also reduced significantly in presence of algal inoculation. Overall our findings suggest that the application of algae along with biochar in the problem soil could reduce the adsorption of P which would influence the availability of P.
基金supported by the National Natural Science Foundation of China(32372268)the China Postdoctoral Science Foundation(2023M743532).
文摘With the proceeding of global warming and water eutrophication,the phenomenon of green tide has garnered significant societal interest.Consequently,researchers had increasingly focused on the potential applications of green algae biomass,particularly its polysaccharides.The polysaccharide serves as the primary active constituent of green algae and has demonstrated numerous advantageous biological activities,including antioxidant,antiviral,anticoagulant,hypolipidemic and immuno-modulatory activities.The favorable bioavailability and solubility of green algae oligosaccharides are attributed to their low molecular weight.So there has been a growing interest in researching green algae polysaccharides and oligosaccharides for the utilization of marine biological resources.This review summarized the extraction,purification,chemical structure,composition,biological activity,and potential applications prospect of polysaccharides and oligosaccharides derived from green algae.The review could be helpful for expanding the applications of polysaccharides and oligosaccharides of green algae.
文摘In the paper, under the framework of exploring the interaction between algae and bacteria, an algae-bacteria ecological model was established to analyze the interaction mechanism and growth coexistence mode between algicidal bacteria and algae. Firstly, mathematical work mainly provided some threshold conditions to ensure the occurrence of transcritical bifurcation and saddle-node bifurcation, which could provide certain theoretical support for selecting key ecological environmental factors and numerical simulations. Secondly, the numerical simulation work dynamically displayed the evolution process of the bifurcation dynamic behavior of the model (2.1) and the growth coexistence mode of algae and algicidal bacteria. Finally, it was worth summarizing that intrinsic growth rate and combined capture effort of algae population had a strong influence on the dynamic behavior of the model (2.1). Furthermore, it must also be noted that transcritical bifurcation and saddle-node bifurcation were the inherent driving forces behind the formation of steady-state growth coexistence mode between algicidal bacteria and algae. In summary, it was hoped that the results of this study would contribute to accelerating the study of the interaction mechanism between algicidal bacteria and algae.
文摘Bisphenol A (BPA) is the primary chemical used in the production of epoxy resins but as of today is not widely available in a bio-based form. BPA is also classified as a substance of very high concern due to its reproductive toxicity and endocrine-disrupting effects. Phlorotannins, a type of polyphenols, offer a promising structural alternative to bisphenol A as a more sustainable option. They are found in high quantities in brown algae, which are already harvested for alginate production. As a result, phlorotannins present an under-researched yet promising marine resource for the chemical industry, particularly in the area of epoxy resin formulation. In this study, a model epoxy resin compound based on phloroglucinol, the simplest phlorotannin, was chosen to explore its reactivity and the thermo-mechanical properties of epoxy resins based thereof. As hardeners well-established systems like isophorone diamine for ambient temperature cure as well as heat-curing anhydrides and dicyandiamide were used. Across all cases, thermosets with glass transition temperatures above 100?C were achieved under cross-linking conditions similar to those used today. One phthalic anhydride derivative yielded a glass transition temperature of 198?C, highlighting the significant potential of these algae-based epoxy resins for industrial uses, such as impregnating resins for fiber-reinforced plastics.
文摘By mild PAGE method, 11, 11, 7 and 9 chlorophyll_protein complexes were isolated from two species of siphonous green algae (Codium fragile (Sur.) Hariot and Bryopsis corticulans Setch.), green alga (Ulothrix flacca (Dillw.) Thur.), and spinach (Spinacia oleracea Mill.), respectively. Apparent molecular weights, Chl a/b ratios, distribution of chlorophyll, absorption spectra, low temperature fluorescence spectra of these complexes were determined, and compared with one another. PSⅠ complexes of two siphonous green algae are larger in apparent molecular weight because of the attachment of relative highly aggregated LHCⅠ. Four isolated light_harvesting complexes of PSⅡ are all siphonaxanthin_Chl a/b_protein complexes, and they are not monomers and oligomers like those in higher plants. Especially, the absence of 730 nm fluorescence in PSⅠ complexes indicates a distinct structure and energy transfer pattern.
基金Supported by Special Project for Marine Fisheries Science and Technology and Industrial Development of Guangdong Province(A201508A05)Regional Demonstration Project of Marine Economy Innovation and Development of Guangdong Province(GD2012-A03-012)~~
文摘[Objective] The biological characteristics and pathogenicities of Shewanella algae and Shewanella abalone from Babylonia were studied in this paper. [Method]The hemolytic bacteria were isolated from the hepatopancreas of Babylonia suffered from proboscis edema with blood agar plate. The dominant bacterial community in the ill Babylonia was identified by 16 S r DNA sequence analysis, and the bacterial cultural and biochemical characteristics and pathogenicities were studied. [Result]The Shewanella bacteria, including Shewanella algae and Shewanella abalone, are the dominant bacterial community in Babylonia suffered from proboscis edema.The colony characteristics of Shewanella algae in nutrient agar medium, TCBS agar medium and CHROMagar vibrio colored medium were similar to those of Shewanella abalone. Shewanella algae possessed β-hemolysis and Shewanella abalone possessed α-hemolysis in the blood agar plate. The biochemical reaction of Shewanella algae and Shewanella abalone was all of non-fermentation type. The results of artificial infection test showed that half lethal dose(LD50) of the test strains of Shewanella algae was 10-5.50/0.1 ml. The test strains of Shewanella algae have strong toxicity, and could cause mice and chickens to die of sepsis with mortality of100%. The mortality of Babylonia infected with Shewanella algae was 10%; while the survived Babylonia lost the ability of moving and intaking for a long time, but they were not suffered from proboscis edema. There was no death in mice or chicks infected with Shewanella abalone, but their livers and spleens were slightly hyperemic and swelling. There was also no death in Babylonia infected with Shewanella abalone, but their intaking and moving ability was lost for a short time.[Conclusion] Although Shewanella algae and Shewanella abalone were the dominant bacteria in Babylonia suffered from proboscis edema, they were not the main pathogenic bacteria for proboscis edema. Shewanella algae had strong pathogenicity to mice, chicks and Babylonia, while Shewanella abalone showed no marked pathogenicity to those experimental animals in this study.
基金Supported by China Agriculture Research System (CARS-49)~~
文摘In order to better monitor N and P pollutants, heavy metals, pesticides and other organic pollutants in water areas, we researched sensitivity and tolerance of aquatic algae on water environment and effects of the pollutants on algae population, analyzing toxin and enrichment of pollutants on algae. The results indicated that aquatic alga is a better indicator for some pollutants in water, for which water contamination can be surveyed and analyzed rapidly.
基金Supported by The Project of Shanghai Scientific and Technological Commission(08DZ1203102,08dz1203002,08dz1203101)
文摘To understand the spatial and temporal variation characteristics of blue algae in summer in Lake Dianshan,the phytoplankton in Lake Dianshan from June to September in 2009 was surveyed. It found 11 genera and 28 species blue algae in total. Microcystis,Oscillatoria and Chroococcus were the main composition communities of blue algae in Lake Dianshan in summer. In the survey period,the average density of blue algae in Lake Dianshan was 16.48×106 cells/L which changed during 1.01×106-59.76×106 cells/L. The characteristics were:September > July > August > June. The mass propagation and aggregation of Microcystis in September caused that the water blooms phenomenon in the partial water areas was serious. In the space,the average density of blue algae in the west and southwest parts of Lake Dianshan was bigger than in the east and southeast. When the nutritive matter was sufficient,the temperature was the main factor which affected the generation and disappearance of blue algae water blooms. The wind direction was also an important factor which affected the distribution of blue algae.
基金Supported by Department of Education Key Item in Guizhou Province (200910040)Guizhou Province UNRISD Research Item (SY20103176)Guizhou Province Fund Item(20082239)~~
文摘[Objective] The research aimed to know the ecological environment pollution characteristics of Hongfeng Lake water area and the evolution rule,which provided the theory basis for improving the water quality condition.[Method] Based on the investigation and research of indoor and outdoor,the water quality,aquatic ecosystem,pollution characteristic of sediment and occurrence law of algae blooms in Hongfeng Lake were comprehensively analyzed by combining with the relevant literatures.[Result] Hongfeng Lake was in moderate-heavy eutrophication situation,and the water quality was V-bad V class.The sediment accumulated a lot of nutrient salt,which was the important pollution source of eutrophication in Hongfeng Lake Reservoir.The aquatic ecosystem degraded,and it was easy to form the algae blooms.[Conclusion] The pollution treatment of Hongfeng Lake was extremely urgent.
文摘Microcystins (MCYSTs) isolated from blue-green algae,are hepatotoxic polypeptides.It will induce severe intrahepatic hemorrhage and liver necrosis at low concentrations in rats and mice.MCYST- LR is one of MCYSTs which consists of 2 variable L- amino acids(leucine and arginine),3 D-amino acids and 2 unusualamino acids(including Adda).MCYSTs bind to protein phosphatase 1 and 2A,and strongly inhibit their activities.The resultant increase of phosphoprotein was referred to be involved in tumor-promoting activity in liver.According to the above results and animal study,MCYST-LR is a potent liver tumor promoter.There were 9 positive from 30 samples of pond-ditch water in high endemic county-Haimen by high-peformance liquid chromatograph and 3 already confirmed by liquid chromograph/mass spectrometer.The quantities of MCYSTs were different between drinking water of liver cancer cases and controls groups.122±0.057and 0.072±0.044μg/200ml respectively) by ELISA. It is not easy to remove by conventional water treatment procedures.The relationship between MCYSTs and oncogenes and anti-oncogenes are under studying.
文摘[Objective] The research aimed to improve the method of isolation of algae.[Method] The samples were cultured in liquid medium after pre-culture in natural medium.[Result]12 species of algae were isolated from the sample.[Conclusion] The method is useful and easy to be handled.
文摘Algae have become an area of intensive research in many fields of study. Areas of application are becoming increasingly diverse with the advent of technologies particularly in the mass production of algae biomass. Algae contain complex bioactive compounds and these are gaining importance in emerging technologies with nutritional and environmental applications. In this study, a preliminary investigation evaluated 15 species of algae from the major categories of marine and fresh water algae for their potential as inclusions in ruminant diets for management of greenhouse gas emissions. It was hypothesized that algae would positively affect rumen fermentation and gas production while reducing methane production. The hypothesis was tested using an Ankom automated gas monitoring system and rumen fluid from Bos indicus steers fed tropical forage diets. The results were variable between algae species with some showing a significant reduction in total gas and methane production, with others increasing gas and fermentation. The red and brown algae stand out as having potential for greenhouse gas mitigation with the brown alga Cystoseira having the most prominent effect. The effects observed on fermentation may be manipulated through dosage management and beneficial effects could be potentially maximized by preparing combinations of algal supplements. It has been demonstrated in this study that algae have the potential to assist in rumen fermentation management for improved gas production, and greenhouse gas abatement.
文摘Based on the data of 18 cases during the past 30 years from 1978 to 2007,the major meteorological conditions for outbreak of blue-green alga in Hongze Lake were analyzed.The results showed that the main meteorological conditions that affected the production and outbreak of blue-green alga were unusual high monthly average temperature,less precipitation and more sunshine hours in ten days.Through the selection of 1 or 0 factors on the values of above meteorological conditions over the years,if the conditions were accorded with the outbreak of blue-green alga,the factor was signed as 1,or it would be signed as 0;if there was outbreak of blue-green alga within ten days,it was signed as 1,or it would be signed as 0;crossing interrelated and integrated prediction method was adopted to establish the prediction equation for outbreak of blue-green alga,the historical fitting rate was 87.5%,and the predicting accuracy rate in 2008-2009 was 87.5%.In addition to meteorological conditions,outbreak of blue-green alga was also influenced by industrial pollutions,etc.,which should be considered in the forecasting procedures.