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algae

人与生物圈 1996年第2期 47-48页

作者： Tian Xiaojing

algae are the most ancient green plants in the world. Blue algae (Cyanophyceae) originated in the vast sea about 3200 million years ago. The great significance of this event lies in not only making the sea water blue green, but most importantly oxygen being released for the first time into the air by blue algae during their photosynthetic reaction, which changes the atmosphere from a reduced state

关键词： algae

Microscopic analysis on eukaryotic algae and cyanobacteria in nine seasonal lakes and ponds in Vestfjella,Dronning Maud Land,Antarctica

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Advances in Polar Science 2024年第2期35卷 206-218页

作者： Lauri ARVOLA Matti LEPPÄRANTA LI Zhijun Lammi Biological Station University of HelsinkiLammi FI-16900Finland Department of Physics University of HelsinkiHelsinki FI-00014Finland State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116023China

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 *** 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 *** 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 *** taxon with highest frequency among the samples(n=79)was Mesotaenium ***,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 *** 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 *** suggests the importance of sediment in supporting biological diversity in these ultraoligotrophic lakes and ponds.

关键词： Antarctic continental lakes Antarctic continental ponds cyanobacteria algae protozoa rotifers tardigrada

Dynamic Analysis of an algae-Bacteria Ecological Model

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Journal of Applied Mathematics and Physics 2024年第1期12卷 362-382页

作者： Gaopeng Sun Hengguo Yu School of Mathematics and Physics Wenzhou University Wenzhou China

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.

关键词： algae Algicidal Bacteria Transcritical Bifurcation Saddle-Node Bifurcation Coexistence Mode

Interaction between Biochar and algae on Problem Soil

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Journal of Materials Science and Chemical Engineering 2024年第1期12卷 56-68页

作者： Tazeen Fatima Khan Abdullah Al Mamun Nipu Department of Soil Water and Environment University of Dhaka Dhaka Bangladesh Department of Virology International Centre for Diarrhoeal Disease Research Bangladesh (ICDDR B) Dhaka Bangladesh

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.

关键词： Biochar algae Problem Soil Interaction Phosphorus

algae (Raphidocelis subcapitata) mitigate combined toxicity of microplastic and lead on Ceriodaphnia dubia

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Frontiers of Environmental Science & Engineering 2020年第6期14卷 65-74页

作者： Xuesong Liu Jianmin Wang Department o f Civil Architectural and Environmental EngineeringMissouri University of Science and TechnologyRollaMO 65409USA The Center for Research in Energy and Environment(CREE) Missouri University of Science and TechnologyRollaMO 65409USA

Microplastics(MPs)have been recognized as a new class of emerging contaminants in recent *** not only directly impact aquatic organisms,but also indirectly impact these organisms by interacting with background toxins in the ***,under realistic environmental conditions,algae,a natural food for aquatic organisms,may alter the toxicity pattern related to *** this research,we first examined the toxicity of MPs alone,and their effect on the toxicity of lead(Pb)on Ceriodaphnia dubia(***),a model aquatic organism for toxicity ***,we investigated the effect of algae on the combined toxicity of MPs and *** observed that,MPs significantly increased Pb toxicity,which was related to the increase in soluble Pb concentration and the intake of Pb-loaded MPs,both of which increased the accumulation of Pb in *** presence of algae mitigated the combined toxicity of MPs and Pb,although algae alone increased Pb ***,the toxicity mitigation through algae uptake came from mechanisms other than Pb accumulation,which will need further investigation.

关键词： Microplastic Lead Toxicity algae C.dubia

algae （Microcystis and Scenedesmus） absorption spectra and its application on Chlorophyll a retrieval

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Frontiers of Earth Science 2013年第4期7卷 522-530页

作者： Di WU Maosi CHEN Qiao WANG Wei GAO Satellite Environment Center Ministry of Environmental Protection Beijing 100094 China USDA UV-B Monitoring and Research Program Natural Resource Ecology Laboratory Colorado State University Fort Collins CO 80521 USA Department of Ecosystem Science and Sustainability Colorado State University Fort Collins CO 80521 USA

Blue algae and green algae are the dominant phytoplankton groups that contribute to the eutrophication and the water bloom in inland water of China. The absorption coefficients （spectra） of the algae, which do not change with its intrinsic optical characteristics and the observation geometry, are strictly additive quantities. The characteristics of the absorption spectra of the two algae are presented. The pure blue algae and the pure green algae cultured in the laboratory environment are diluted and mixed at ten volume ratios. The Quantitative Filter Technique was applied to measure their absorption spectra. The ＂hot-ethanol extraction＂ method was chosen to calculate their concentration of Chlorophyll a. The retrieval algorithm developed in this study extracts the mapping information between each individual alga and their Chlorophyll a concentration via Continuous Wavelet Transform, and retrieves the Chlorophyll a concentration of each alga in their mixture using a trust region optimizer. The results show that the retrieved and the measured Chlorophyll a concentrations of the blue algae and the green algae components in the ten mixture match well with the average relative error of 5.55%.

关键词： algae absorption coefficient spectra Chlorophyll a trust region Continuous Wavelet Transform

Discovering the Association of algae with Physicochemical Variables in Erhai Lake

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Chinese Journal of Electronics 2020年第2期29卷 265-272页

作者： LIU Chuanlu WANG Shuliang YUAN Hanning GENG Jing School of Computer Science and Technology Beijing Institute of Technology

Erhai Lake is the seventh largest freshwater lake in China where has been encountered with water pollution by the algae. One of important indicator of the water quality is the density of algae in the water, and the growth rate of algae is eutrophication.A novel method is proposed to discover the association of algae with physicochemical variables related to the algae growth in Erhai Lake, by integrating Maximal information coefficient(MIC) and association rules. To measure the correlation between variables, a new aspect on association rules with non-occurring domain is purposed,which decreases one item in antecedent. The correlation results present significantly in the density levels of algae,which is beneficial to control the level of physicochemical in the water for preventing the increasing number of algae.

关键词： Erhai Lake algae Maximal information coefficient(MIC) Association rules

Toxic effects of three perfluorinated or polyfluorinated compounds(PFCs)on two strains of freshwater algae:Implications for ecological risk assessments

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Journal of Environmental Sciences 2023年第9期131卷 48-58页

作者： Liangliang Zhang Xiaowei Zheng Xianglin Liu Jue Li Yanyao Li Zeming Wang Nan Zheng Xiangrong Wang Zhengqiu Fan Department of Environmental Science and Engineering Fudan UniversityShanghai 200433China Laboratory of Industrial Water and Ecotechnology Department of Green Chemistry and TechnologyGhent UniversityKortrijk 8500Belgium Jinan Environmental Research Academy Jinan 250102China

Perfluorinated or polyfluorinated compounds(PFCs)continue entering to the environmental as individuals or mixtures,but their toxicological information remains largely ***,we investigated the toxic effects and ecological risks of Perfluorooctane sulfonic acid(PFOS)and its substitutes on prokaryotes(Chlorella vulgaris)and eukaryotes(Microcystis aeruginosa).Based on the calculated EC50 values,the results showed that PFOS was significantly more toxic to both algae than its alternatives including Perfluorobutane sulfonic acid(PFBS)and 6:2 Fluoromodulated sulfonates(6:2 FTS),and the PFOS-PFBS mixture was more toxic to both algae than the other two PFC *** action mode of binary PFC mixtures on Chlorella vulgaris was mainly shown as antagonistic and on Microcystis aeruginosa as synergistic,by using Combination index(CI)model coupled with Monte Carlo *** mean risk quotient(RQ)value of three individual PFCs and their mixtures were all below the threshold of 10^(−1),but the risk of those binary mixtures were higher than that of PFCs individually because of their synergistic *** findings contribute to enhance the understanding of the toxicological information and ecological risks of emerging PFCs and provide a scientific basis for their pollution control.

关键词： Toxicity Combination index model Monte Carlo simulation Action mode algae

Organic matter produced by algae and cyanobacteria: Quantitative and qualitative characterization

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Journal of Environmental Sciences 2013年第6期25卷 1089-1097页

作者： Maud Leloup Rudy Nicolau Virginie Pallier Claude Yprmian Geneviève Feuillade-Cathalifaud University of Limoges EA 4330Groupement de Recherche EauSolEnvironnement(GRESE)ENSILParc d'ESTER Technople16 rue AtlantisF-87068 Limoges CedexFrance UMR 7245 MCAM MNHN-CNRS Equipe CyanobactériesCyanotoxines et EnvironnementMuséum National d'Histoire NaturelleCase 3912 rue BuffonF-75231 Paris Cedex 05France

This work aims at characterizing organic matter produced by an alga Euglena gracil~ and a cyanobacteria Microcystis aeruginosa and assessing the evolution of its characteristics during growth. A culture medium was optimized. The species growth phases were monitored using both visible spectrophotometry and flow cytometry cell counting. Organic matter fractionation according to hydrophobicity and specific UV absorbance （SUVA） index were used to specifically characterize the produced algal organic matter （AOM）. The AOM characteristics were both growth phase and species dependent. However, a similar evolution was observed. The hydrophilic fraction （HPI） was the major fraction whatever the growth phases and was almost the only one produced during lag and exponential phases. It represented around 75% of AOM during exponential phase and then decreased when the stationary phase appeared. It represented 46% and 60% of the AOM during late decline phase for the cyanobacteria and the alga respectively. The hydrophobic （HPO） and transphilic （TPH） fractions started to appear from the beginning of the stationary phase with more hydrophobic compounds coming from intracellular organic material of dying cells. HPO and TPH percentages still increased during the decline phase probably because of two additional processes： photo-dissolution and leaching of particulate organic matter from cells fragments. A comparison of AOM during late decline phase and natural organic matter （NOM） from Glane River （France） underlined that AOM was more fiydrophilic and presented a lower SUVA for each fractions than NOM. However, the difference between NOM and AOM hydrophobicity narrowed during decline phase.

关键词： algae cyanobacteria organic matter XAD fractionation SUVA flow cytometry