the biomass of ice algal communities in coastal sea ice off zhongshan Station, antarctica were monitored from april to december 1992. The maximum Thickness of ice cover was 1. 74 m in november/december and covered-sno...the biomass of ice algal communities in coastal sea ice off zhongshan Station, antarctica were monitored from april to december 1992. The maximum Thickness of ice cover was 1. 74 m in november/december and covered-snow was less than35 cm in depth throughout the study period. Brown layers occurred in 2～5 cm of theIce bottom in late april and november, with chlorophyll a peak values of 360. 7 and2810 mg/m3 respectively. The integrated chlorophyll a values ranged from 1. 17 to59. 7 mg/m2 with the peak occurring in november when ice algae bloomed, and theValues never exceeded 6 mg/m2 before mid october except at one site, the highest valueOccurred in april and then decreased nuctuatedly throughout the year. The biomassWas concentrated mainly in the bottom of the ice, and might be also partly concentratedIn the interior sections where autumn bloom had occurred. The dominant diatoms wereComposed of nitzschia lecointei, n. Barkleyi, n. Cylindrus in austral autumn and Amphiphiprora kjellmanii, berkeleya rutilans, nitzschia lecointei in austral spring, andShowed some difference at sites owing to the environmental conditions.展开更多
This paper reports the results of separation and identification of the pigments from ice algae in the adjacent waters (62°12′30″S～62°14′30″S, 58°53′W～ 58°57′W) of Great Wall Station, Antarc...This paper reports the results of separation and identification of the pigments from ice algae in the adjacent waters (62°12′30″S～62°14′30″S, 58°53′W～ 58°57′W) of Great Wall Station, Antarctica during the icing Pened (from June 1988～ December 1988) and the discussion is also made on the composition and seasonal variations of the pigments of ice algae in that area as well as their roles in marine ecosystems. The results indicate that 15 kinds of pigments have been separated from ice algae, of which 13 kinds can be identified. They are respeCtively: carotene, pheophytin-a, chlorophyll-a, -b, -c, xanthophyll, fucoxanthin, chlorophyllide-a, violaxanthin, pheophorbide-a, chlorophyllin-a, derivative of chlorophyll-c (diadinoxanthin), but two kinds of pigments can not be identified. There are distinct seasonal variations in the pigments of ice algae at that sea area.展开更多
Antarctic ice microalgae Chlamydomonas sp.ICE-L can survive and thrive in Antarctic sea ice.In this study,Chlamydomonas sp.ICE-L could survive at the salinity of 132‰ NaCl.SDS-PAGE showed that the density of 2 bands...Antarctic ice microalgae Chlamydomonas sp.ICE-L can survive and thrive in Antarctic sea ice.In this study,Chlamydomonas sp.ICE-L could survive at the salinity of 132‰ NaCl.SDS-PAGE showed that the density of 2 bands（26 and 36 kD） decreased obviously at the salinity of 99‰ NaCl compared to at the salinity of 33‰ NaCl.The soluble proteins in Chlamydomonas sp.ICE-L grown under salinity of 33‰ and 99% NaCl were compared by 2-D gel electrophoresis.After shocking with high salinity,8 protein spots were found to disappear,and the density of 28 protein spots decreased.In addition,19 protein spots were enhanced or induced,including one new peptide（51 kD）.The changes of proteins might be correlated with the resistance for Chlamydomonas sp.ICE-L to high salinity.展开更多
Primary production in the Bering and Chukchi Seas is strongly influenced by the annual cycle of sea ice. Here pelagic and sea ice algal ecosystems coexist and interact with each other. Ecosystem modeling of sea ice as...Primary production in the Bering and Chukchi Seas is strongly influenced by the annual cycle of sea ice. Here pelagic and sea ice algal ecosystems coexist and interact with each other. Ecosystem modeling of sea ice associated phytoplankton blooms has been understudied compared to open water ecosystem model applications. This study introduces a general coupled ice-ocean ecosystem model with equations and parameters for 1-D and 3-D applications that is based on 1-D coupled ice-ocean ecosystem model development in the landfast ice in the Chukchi Sea and marginal ice zone of Bering Sea. The biological model includes both pelagic and sea ice algal habitats with 10 compartments： three phytoplankton （pelagic diatom, flagellates and ice algae： D, F, and Ai） , three zooplankton （copepods, large zooplankton, and microzooplankton ： ZS, ZL, ZP） , three nutrients （ nitrate ＋ nitrite, ammonium, silicon ： NO3 , NH4, Si） and detritus （Det）. The coupling of the biological models with physical ocean models is straightforward with just the addition of the advection and diffusion terms to the ecosystem model. The coupling with a multi-category sea ice model requires the same calculation of the sea ice ecosystem model in each ice thickness category and the redistribution between categories caused by both dynamic and thermodynamic forcing as in the physical model. Phytoplankton and ice algal self-shading effect is the sole feedback from the ecosystem model to the physical model.展开更多
Sea-ice algae are a paramount feature of polar marine ecosystems and ice algal standing stocks are characterized by a high spatio-temporal variability. Traditional sampling techniques, e.g., ice coring, are laborinte...Sea-ice algae are a paramount feature of polar marine ecosystems and ice algal standing stocks are characterized by a high spatio-temporal variability. Traditional sampling techniques, e.g., ice coring, are laborintensive, spatially limited and invasive, thereby limiting our understanding of ice algal biomass variability patterns. Thishas consequences for quantifying ice-associated algal biomass distribution, primary production, and detecting responses to changing environmental conditions. Close-range under-ice optical remote sensing techniques have emerged as a capable alternative providing non-invasive estimates of ice algal biomass and its spatial variability. In this review we first summarize observational studies, using both classical and new methods that aim to capture biomass variability at multiple spatial scales and identify the environmental drivers. We introduce the complex multi-disciplinary nature of under-ice spectral radiation profiling techniquesand discuss relevant concepts of sea-ice radiative transfer and bio-optics. In addition, we tabulate and discuss advances and limitations of different statistical approaches used to correlate biomass and under-ice light spectral composition. We also explore theoretical and technical aspects of using Unmanned Underwater Vehicles （UUV）, and Hyperspectral Imaging （HI） technology in an under-ice remote sensing context. The review concludes with an outlook and way forward to combine platforms and optical sensors to quantify ice algal spatial variability and establish relationships with its environmental drivers.展开更多
The ice algal and phytoplankton assemblages were studied from Nella Fjord near Zhongshan Station, East Antarctica from April 12 to December 30, 1992. Algal blooms occurred about 3 cm thick on the bottom of sea ice in ...The ice algal and phytoplankton assemblages were studied from Nella Fjord near Zhongshan Station, East Antarctica from April 12 to December 30, 1992. Algal blooms occurred about 3 cm thick on the bottom of sea ice in late April and mid November to early December respectively, and a phytoplankton bloom appeared in the underlying surface water in mid December following the spring ice algal bloom. The biomass in ice bottom was 1 to 3 orders of magnitude higher than that of surface water. Amphiprora kjellmanii, Berkeleya sp., Navicula glaciei, Nitzschia barkelyi, N. cylindrus /N. curta, N. lecointei and Nitzschia sp. were common in the sea ice temporarily or throughout the study period. The biomass in a certain ice segment was decreased gradually and the dominant species were usually succeeded as the season went on. Nitzschia sublineata and Dactyliosolen antarctica were two seasonal dominant species only observed in underlying water column. The assemblages between bottom of ice and underlying surface water were different except when spring ice algae bloomed. The evidence shows that the ice algal blooms occurred mainly by in situ growth of ice algae, and the phytoplankton bloom was mostly caused by the release of ice algae.展开更多
Abundance, biomass and composition of the ice algal and phytoplankton communities were investigated in the southeastern Laptev Sea in spring 1999. Diatoms dominated the algal communities and pennate diatoms dominated ...Abundance, biomass and composition of the ice algal and phytoplankton communities were investigated in the southeastern Laptev Sea in spring 1999. Diatoms dominated the algal communities and pennate diatoms dominated the diatom population. 12 dominant algal species occurred within sea ice and underlying water column, including Fragilariopsis oceanica, F. cylindrus, Nitzschla frigida, N. promare, Achnanthes taeniata, Nitzschia neofrigida, Navicula pelagica , N. vanhoef fenii, N. septentrionalls, Melosiraarctica , Clindrotheca closterium and Pyramimonas sp. The algal abundance of bottom 10cm sea ice varied between 14.6 and 1562.2 × 10^4 cells 1^-1 with an average of 639.0 × 10^4 cells 1^-1 , and the algal biomass ranged from 7.89 to 2093.5μg C 1^-1 with an average of 886.9μg C1^-1 , which were generally one order of magnitude higher than those of sub-bottom ice and two orders of magnitude higher than those of underlying surface water. The integrated algal abundance and biomass of lowermost 20 cm ice column were averagely 7.7 and 12.2 times as those of upper 20 m water column, respectively, suggesting that the ice algae might play an important role in maintaining the coastal marine ecosystem before the thawing of sea ice. Ice algae influenced the phytoplankton community of the underlying water column. However, the ＂seeding＂ of ice algae for phytoplankton bloom was negligible because of the low phytoplankton biomass within the underlying water column.展开更多
Marine biological and environmental investigations were carried out on the coastatl waters off Great Wall Station (62°13's, 58°58'W) on King George Island, Antarctica, from November 17, 1988, to Marc...Marine biological and environmental investigations were carried out on the coastatl waters off Great Wall Station (62°13's, 58°58'W) on King George Island, Antarctica, from November 17, 1988, to March 3,1989. Coastal fast ice covered inner part of Great Wall Bay until mid-December 1988, which allowed us to take ice core sampling and observations from mid-November to early December 1988. During this period, ice thickness ranged from 90 to 70cm with baout 20cm of snow cover. About 5cm brown layer occured in the middle part of fast ice core collected on November 20, 1988 at site 2, and two brown layers occured in the interior of ice core collected on November 17,20 and 26, 1988 at site 5.In comparison to the water column, chlorophyll-a concentration in fast ice was higher, which ranged from 2.55 to 56.84mg/m8, and most of them were concentracted in the interior layers of sea ice rather than in the bottom layer often observed in other sea ice areas, such as in Syowa, Davis, Casey Station and McMurdo Sound areas, etc. This might be a result of the difference in structure and formation procese of sea ice.Meanwhile, temperature, transparency, nutrients and chlorophyll-a in water column were measured. Microalgal assemblages both in fast ice and water column of Great Wall Bay were reported.展开更多
Antarctic ice microalga Chlamydomonas sp. can thrive undisturbed under high UV radiation in the Antarctic ice layer. However, it is unknown that the initial adaptation mechanisms in protein level occurring in response...Antarctic ice microalga Chlamydomonas sp. can thrive undisturbed under high UV radiation in the Antarctic ice layer. However, it is unknown that the initial adaptation mechanisms in protein level occurring in response to high UV radiation. Global-expression profiling of proteins in response to stress was analyzed by two-dimensional electrophoresis （2-DE） and image analysis. In the 2-DE analysis, protein preparation is the key step. Three different protein extract methods were compared, and the results showed that the trichloroacetic acid （TCA）-acetone fractional precipitation method was the fittest one. At the same time, the proteins in Chlamydomonas sp. were compared in 2-DE way, and the synthesis of seven protein spots was found disappeared and 18 decreased after exposed to UV-B radiation. In addition, 14 protein spots were enhanced or induced, among which two new peptides （20 and 21 kDa） appeared whose isoelectric point （pI） was 7.05 and 4.60 respectively. These changed proteins might act as key role in the acclimation of Antarctic ice microalga to UV-B radiation展开更多
Nitrogen removal from media by microalgae provides the potential benefit of producing lipids for biodiesel and biomass. However, research is limited on algal growth and biomass under different nitrogen sources and pro...Nitrogen removal from media by microalgae provides the potential benefit of producing lipids for biodiesel and biomass. However, research is limited on algal growth and biomass under different nitrogen sources and provides little insight in terms of biofuel production. We studied the influences of nitrogen sources on cell growth and lipid accumulation of Chlamydomonas sp. ICE-L, one of a promising oil rich micro algal species. Chlamydomonas sp.ICE-L grown in NH_4 Cl medium had maximum growth rate. While the highest dry biomass of 0.28 g/L was obtained in media containing NH_4NO_3, the highest lipid content of 0.21 g/g was achieved under nitrogendeficiency condition with a dry biomass of 0.24 g/L. In terms of total polyunsaturated fatty acids（PUFAs）production, NH_4NO_3 and NH_4 Cl media performed better than nitrogen-deficiency and KNO_3 media.Furthermore, NH_4NO_3 and NH_4 Cl media elucidated better results on C18：3 and C20：5 productions while KNO_3and-N conditions were better in C16：0, C18：1 and C18：2, comparatively.展开更多
文摘the biomass of ice algal communities in coastal sea ice off zhongshan Station, antarctica were monitored from april to december 1992. The maximum Thickness of ice cover was 1. 74 m in november/december and covered-snow was less than35 cm in depth throughout the study period. Brown layers occurred in 2～5 cm of theIce bottom in late april and november, with chlorophyll a peak values of 360. 7 and2810 mg/m3 respectively. The integrated chlorophyll a values ranged from 1. 17 to59. 7 mg/m2 with the peak occurring in november when ice algae bloomed, and theValues never exceeded 6 mg/m2 before mid october except at one site, the highest valueOccurred in april and then decreased nuctuatedly throughout the year. The biomassWas concentrated mainly in the bottom of the ice, and might be also partly concentratedIn the interior sections where autumn bloom had occurred. The dominant diatoms wereComposed of nitzschia lecointei, n. Barkleyi, n. Cylindrus in austral autumn and Amphiphiprora kjellmanii, berkeleya rutilans, nitzschia lecointei in austral spring, andShowed some difference at sites owing to the environmental conditions.
文摘This paper reports the results of separation and identification of the pigments from ice algae in the adjacent waters (62°12′30″S～62°14′30″S, 58°53′W～ 58°57′W) of Great Wall Station, Antarctica during the icing Pened (from June 1988～ December 1988) and the discussion is also made on the composition and seasonal variations of the pigments of ice algae in that area as well as their roles in marine ecosystems. The results indicate that 15 kinds of pigments have been separated from ice algae, of which 13 kinds can be identified. They are respeCtively: carotene, pheophytin-a, chlorophyll-a, -b, -c, xanthophyll, fucoxanthin, chlorophyllide-a, violaxanthin, pheophorbide-a, chlorophyllin-a, derivative of chlorophyll-c (diadinoxanthin), but two kinds of pigments can not be identified. There are distinct seasonal variations in the pigments of ice algae at that sea area.
基金supported by the National Natural Science Foundation of China(No.40876107No.40876102)Marine Science Foundation for Young Scientists of the State Oceanic Administration(2010122)
文摘Antarctic ice microalgae Chlamydomonas sp.ICE-L can survive and thrive in Antarctic sea ice.In this study,Chlamydomonas sp.ICE-L could survive at the salinity of 132‰ NaCl.SDS-PAGE showed that the density of 2 bands（26 and 36 kD） decreased obviously at the salinity of 99‰ NaCl compared to at the salinity of 33‰ NaCl.The soluble proteins in Chlamydomonas sp.ICE-L grown under salinity of 33‰ and 99% NaCl were compared by 2-D gel electrophoresis.After shocking with high salinity,8 protein spots were found to disappear,and the density of 28 protein spots decreased.In addition,19 protein spots were enhanced or induced,including one new peptide（51 kD）.The changes of proteins might be correlated with the resistance for Chlamydomonas sp.ICE-L to high salinity.
基金supported by North Pacific Research Board(NPRB) grant 607(paper contribution number 202)NSF grant ARC-0652838+1 种基金DOE/EPSCoR grant DE-FG02-08ER46502.This is GLERL Contribution No.1499 and DOE/EPS-CoRInternational Arctic Research Center,University of Alaska Fairbanks supported this study through the JAMSTEC-IARC Research Agreement.
文摘Primary production in the Bering and Chukchi Seas is strongly influenced by the annual cycle of sea ice. Here pelagic and sea ice algal ecosystems coexist and interact with each other. Ecosystem modeling of sea ice associated phytoplankton blooms has been understudied compared to open water ecosystem model applications. This study introduces a general coupled ice-ocean ecosystem model with equations and parameters for 1-D and 3-D applications that is based on 1-D coupled ice-ocean ecosystem model development in the landfast ice in the Chukchi Sea and marginal ice zone of Bering Sea. The biological model includes both pelagic and sea ice algal habitats with 10 compartments： three phytoplankton （pelagic diatom, flagellates and ice algae： D, F, and Ai） , three zooplankton （copepods, large zooplankton, and microzooplankton ： ZS, ZL, ZP） , three nutrients （ nitrate ＋ nitrite, ammonium, silicon ： NO3 , NH4, Si） and detritus （Det）. The coupling of the biological models with physical ocean models is straightforward with just the addition of the advection and diffusion terms to the ecosystem model. The coupling with a multi-category sea ice model requires the same calculation of the sea ice ecosystem model in each ice thickness category and the redistribution between categories caused by both dynamic and thermodynamic forcing as in the physical model. Phytoplankton and ice algal self-shading effect is the sole feedback from the ecosystem model to the physical model.
基金supported by the Australian Research Council’s Special Research Initiative for Antarctic Gateway Partnership (Project ID SR140300001)EC was supported by the Antarctic Gateway Partnership+3 种基金the University of Tasmania’s Institute for Marine and Ph.D. programKMMs contribution to this work was supported by the Australian Governments Cooperative Research Centres Program through the Antarctic Climate and Ecosystems Cooperative Research Centre, through Australian Antarctic Science project #4298 and through a fellowship at the Hanse-Wissenschaftskolleg (Delmenhorst, Germany)LCLH’s contribution to the work was supported by AUFF (Aarhus University Research Foundation) grant nr. 20858. (Delmenhorst, Germany)LCLH’s contribution to the work was supported by AUFF (Aarhus University Research Foundation) grant nr. 20858
文摘Sea-ice algae are a paramount feature of polar marine ecosystems and ice algal standing stocks are characterized by a high spatio-temporal variability. Traditional sampling techniques, e.g., ice coring, are laborintensive, spatially limited and invasive, thereby limiting our understanding of ice algal biomass variability patterns. Thishas consequences for quantifying ice-associated algal biomass distribution, primary production, and detecting responses to changing environmental conditions. Close-range under-ice optical remote sensing techniques have emerged as a capable alternative providing non-invasive estimates of ice algal biomass and its spatial variability. In this review we first summarize observational studies, using both classical and new methods that aim to capture biomass variability at multiple spatial scales and identify the environmental drivers. We introduce the complex multi-disciplinary nature of under-ice spectral radiation profiling techniquesand discuss relevant concepts of sea-ice radiative transfer and bio-optics. In addition, we tabulate and discuss advances and limitations of different statistical approaches used to correlate biomass and under-ice light spectral composition. We also explore theoretical and technical aspects of using Unmanned Underwater Vehicles （UUV）, and Hyperspectral Imaging （HI） technology in an under-ice remote sensing context. The review concludes with an outlook and way forward to combine platforms and optical sensors to quantify ice algal spatial variability and establish relationships with its environmental drivers.
文摘The ice algal and phytoplankton assemblages were studied from Nella Fjord near Zhongshan Station, East Antarctica from April 12 to December 30, 1992. Algal blooms occurred about 3 cm thick on the bottom of sea ice in late April and mid November to early December respectively, and a phytoplankton bloom appeared in the underlying surface water in mid December following the spring ice algal bloom. The biomass in ice bottom was 1 to 3 orders of magnitude higher than that of surface water. Amphiprora kjellmanii, Berkeleya sp., Navicula glaciei, Nitzschia barkelyi, N. cylindrus /N. curta, N. lecointei and Nitzschia sp. were common in the sea ice temporarily or throughout the study period. The biomass in a certain ice segment was decreased gradually and the dominant species were usually succeeded as the season went on. Nitzschia sublineata and Dactyliosolen antarctica were two seasonal dominant species only observed in underlying water column. The assemblages between bottom of ice and underlying surface water were different except when spring ice algae bloomed. The evidence shows that the ice algal blooms occurred mainly by in situ growth of ice algae, and the phytoplankton bloom was mostly caused by the release of ice algae.
基金supported by the National Nature Science Foundation of China(30270112,40006010)the Basic Research Special Project of Chinese Science and Technology Administration(2003DEB5J057)Oceanic Science Foundation of State 0ceanic Administration of China(2003122).
文摘Abundance, biomass and composition of the ice algal and phytoplankton communities were investigated in the southeastern Laptev Sea in spring 1999. Diatoms dominated the algal communities and pennate diatoms dominated the diatom population. 12 dominant algal species occurred within sea ice and underlying water column, including Fragilariopsis oceanica, F. cylindrus, Nitzschla frigida, N. promare, Achnanthes taeniata, Nitzschia neofrigida, Navicula pelagica , N. vanhoef fenii, N. septentrionalls, Melosiraarctica , Clindrotheca closterium and Pyramimonas sp. The algal abundance of bottom 10cm sea ice varied between 14.6 and 1562.2 × 10^4 cells 1^-1 with an average of 639.0 × 10^4 cells 1^-1 , and the algal biomass ranged from 7.89 to 2093.5μg C 1^-1 with an average of 886.9μg C1^-1 , which were generally one order of magnitude higher than those of sub-bottom ice and two orders of magnitude higher than those of underlying surface water. The integrated algal abundance and biomass of lowermost 20 cm ice column were averagely 7.7 and 12.2 times as those of upper 20 m water column, respectively, suggesting that the ice algae might play an important role in maintaining the coastal marine ecosystem before the thawing of sea ice. Ice algae influenced the phytoplankton community of the underlying water column. However, the ＂seeding＂ of ice algae for phytoplankton bloom was negligible because of the low phytoplankton biomass within the underlying water column.
文摘Marine biological and environmental investigations were carried out on the coastatl waters off Great Wall Station (62°13's, 58°58'W) on King George Island, Antarctica, from November 17, 1988, to March 3,1989. Coastal fast ice covered inner part of Great Wall Bay until mid-December 1988, which allowed us to take ice core sampling and observations from mid-November to early December 1988. During this period, ice thickness ranged from 90 to 70cm with baout 20cm of snow cover. About 5cm brown layer occured in the middle part of fast ice core collected on November 20, 1988 at site 2, and two brown layers occured in the interior of ice core collected on November 17,20 and 26, 1988 at site 5.In comparison to the water column, chlorophyll-a concentration in fast ice was higher, which ranged from 2.55 to 56.84mg/m8, and most of them were concentracted in the interior layers of sea ice rather than in the bottom layer often observed in other sea ice areas, such as in Syowa, Davis, Casey Station and McMurdo Sound areas, etc. This might be a result of the difference in structure and formation procese of sea ice.Meanwhile, temperature, transparency, nutrients and chlorophyll-a in water column were measured. Microalgal assemblages both in fast ice and water column of Great Wall Bay were reported.
基金supported by the National Natural Science Foundation of China under contract No.40506005
文摘Antarctic ice microalga Chlamydomonas sp. can thrive undisturbed under high UV radiation in the Antarctic ice layer. However, it is unknown that the initial adaptation mechanisms in protein level occurring in response to high UV radiation. Global-expression profiling of proteins in response to stress was analyzed by two-dimensional electrophoresis （2-DE） and image analysis. In the 2-DE analysis, protein preparation is the key step. Three different protein extract methods were compared, and the results showed that the trichloroacetic acid （TCA）-acetone fractional precipitation method was the fittest one. At the same time, the proteins in Chlamydomonas sp. were compared in 2-DE way, and the synthesis of seven protein spots was found disappeared and 18 decreased after exposed to UV-B radiation. In addition, 14 protein spots were enhanced or induced, among which two new peptides （20 and 21 kDa） appeared whose isoelectric point （pI） was 7.05 and 4.60 respectively. These changed proteins might act as key role in the acclimation of Antarctic ice microalga to UV-B radiation
基金The National Natural Science Foundation of China under contract No.41576187the National Natural Science Foundation of China–Shandong Joint Fund under contract No.U1406402+6 种基金the Basic Scientific Fund for National Public Research Institutes of China under contract No.2015G10the Polar Strategic Foundation of China under contract No.20150303the Public Science and Technology Research Funds Projects of Ocean under contract No.201405015the Scientific and Technological Innovation Project Financially Supported by Qingdao National Laboratory for Marine Science and Technology and the Science under contract No.2015ASKJ02the Science and Technology Planning Project of Shandong Province under contract No.2014GHY115003the Major Projects of Independent Innovation Achievements Transformation in Shandong Province under contract No.2014ZZCX06202Qingdao Entrepreneurship and Innovation Pioneers Program under contract No.15-10-3-15-(44)-zch
文摘Nitrogen removal from media by microalgae provides the potential benefit of producing lipids for biodiesel and biomass. However, research is limited on algal growth and biomass under different nitrogen sources and provides little insight in terms of biofuel production. We studied the influences of nitrogen sources on cell growth and lipid accumulation of Chlamydomonas sp. ICE-L, one of a promising oil rich micro algal species. Chlamydomonas sp.ICE-L grown in NH_4 Cl medium had maximum growth rate. While the highest dry biomass of 0.28 g/L was obtained in media containing NH_4NO_3, the highest lipid content of 0.21 g/g was achieved under nitrogendeficiency condition with a dry biomass of 0.24 g/L. In terms of total polyunsaturated fatty acids（PUFAs）production, NH_4NO_3 and NH_4 Cl media performed better than nitrogen-deficiency and KNO_3 media.Furthermore, NH_4NO_3 and NH_4 Cl media elucidated better results on C18：3 and C20：5 productions while KNO_3and-N conditions were better in C16：0, C18：1 and C18：2, comparatively.
