2014 Vol. 36, No. 10
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2014, 36(10): .
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2014, 36(10): .
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2014, 36(10): 1-11.
doi: 10.3969/j.issn.0253-4193.2014.10.001
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According to a series of important historical maps,i.e.,"Location Map of the South China Sea Islands,Nansha Islands,Zhongsha Islands,Xisha Islands,Yongxing Island and Stone Island,Taiping Island" (drafted by the Internal Ministry of Republic of China in 1946) and "Administration District Map of Republic of China" (published in 1948),the dashed line surrounding the South China Sea Islands represents the determinate maritime boundary of the Republic China. It was shown in these maps that the dashed line is the clear extension of the solid line of China boundary. It should be noted that it was internationally accepted by the worldwide nations and scientific societies that the dashed line was used as the maritime boundary while the solid line was used as the land boundary of a nation. The findings in this work provide historical and scientific evidence for international maritime delimitation over the South China Sea.
According to a series of important historical maps,i.e.,"Location Map of the South China Sea Islands,Nansha Islands,Zhongsha Islands,Xisha Islands,Yongxing Island and Stone Island,Taiping Island" (drafted by the Internal Ministry of Republic of China in 1946) and "Administration District Map of Republic of China" (published in 1948),the dashed line surrounding the South China Sea Islands represents the determinate maritime boundary of the Republic China. It was shown in these maps that the dashed line is the clear extension of the solid line of China boundary. It should be noted that it was internationally accepted by the worldwide nations and scientific societies that the dashed line was used as the maritime boundary while the solid line was used as the land boundary of a nation. The findings in this work provide historical and scientific evidence for international maritime delimitation over the South China Sea.
2014, 36(10): 12-24.
doi: 10.3969/j.issn.0253-4193.2014.10.002
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Carbon and silicon cycles are hot issue of global environmental change,and also an important area of marine science. Base on the investigation in the Bohai sea in May and November 2012,distributions and sources of particulate organic carbon (POC) and biogenic silica (BSi) were discussed. Conclusions are as follows: POC was higher in Spring than in Fall,and its component was consisted by the both the terrestrial and marine materials. BSi distribution showed gradient trend and was influenced by the Huanghe River as well,and a significant linear relationship was found between BSi and POC,which indicated their sources were same to some extent. BSi content in sediment was much higher in the Bohai Sea than other China Sea. Marine phytoplankton and terrestrial phytolith were the main components of BSi in the sediment,and phytoplankton supplied about 62.9% of total BSi. Terrestrial phytolith was found in the sediment,which is of great importance for marine silicon cycle as well.
Carbon and silicon cycles are hot issue of global environmental change,and also an important area of marine science. Base on the investigation in the Bohai sea in May and November 2012,distributions and sources of particulate organic carbon (POC) and biogenic silica (BSi) were discussed. Conclusions are as follows: POC was higher in Spring than in Fall,and its component was consisted by the both the terrestrial and marine materials. BSi distribution showed gradient trend and was influenced by the Huanghe River as well,and a significant linear relationship was found between BSi and POC,which indicated their sources were same to some extent. BSi content in sediment was much higher in the Bohai Sea than other China Sea. Marine phytoplankton and terrestrial phytolith were the main components of BSi in the sediment,and phytoplankton supplied about 62.9% of total BSi. Terrestrial phytolith was found in the sediment,which is of great importance for marine silicon cycle as well.
2014, 36(10): 25-32.
doi: 10.3969/j.issn.0253-4193.2014.10.003
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In the present study,molecular phylogenetic relationships among 16 Sweetlips species collected from Indo-Western Pacific were analyzed based on partial DNA sequences of the molecular marker of mitochondrial NADH dehydrogenase subunit Ⅰ (ND1) gene. The phylogenetic tree was constructed using maximum parsimony and maximum likelihood methods. Two morphologically different groups were formed in the tree. Group Ⅰ was composed of sweetlips with wondrous coloration and diversed patterns,which were mainly found in the Western Pacific. Group Ⅱ was composed of species with monotone color and uniformly dark patterns,which were mostly found in the area of Indian Ocean. Additionally,Diagramma species were all found positionally inside the Plectorhinchus tribe in group Ⅰ in the phylogenetic tree. They were closely related with the sister species Plectorhinchus chaetodonoides and Plectorhinchus picus. Based on the analysis of the genetic distance,the average value between Diagramma and Plectorhinchus was less than that among the interspecies of Plectorhinchus,indicating an extremely close relationship between Diagramma and Plectorhinchus. The result supported the opinion that Diagramma species might be classified into the genus Plectorhinchus.
In the present study,molecular phylogenetic relationships among 16 Sweetlips species collected from Indo-Western Pacific were analyzed based on partial DNA sequences of the molecular marker of mitochondrial NADH dehydrogenase subunit Ⅰ (ND1) gene. The phylogenetic tree was constructed using maximum parsimony and maximum likelihood methods. Two morphologically different groups were formed in the tree. Group Ⅰ was composed of sweetlips with wondrous coloration and diversed patterns,which were mainly found in the Western Pacific. Group Ⅱ was composed of species with monotone color and uniformly dark patterns,which were mostly found in the area of Indian Ocean. Additionally,Diagramma species were all found positionally inside the Plectorhinchus tribe in group Ⅰ in the phylogenetic tree. They were closely related with the sister species Plectorhinchus chaetodonoides and Plectorhinchus picus. Based on the analysis of the genetic distance,the average value between Diagramma and Plectorhinchus was less than that among the interspecies of Plectorhinchus,indicating an extremely close relationship between Diagramma and Plectorhinchus. The result supported the opinion that Diagramma species might be classified into the genus Plectorhinchus.
2014, 36(10): 33-47.
doi: 10.3969/j.issn.0253-4193.2014.10.004
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Using microwave satellite remote sensing data,the sea ice conditions in key regions of Arctic Northeast Passage and Northwest Passage in recent summers were analyzed and the navigable status from 2002 to 2013 were summarized. The navigable period of Northeast Passage was mainly in late August to early October,and navigable windows was 40 to 50 days; South line of Northwest Passage was free to navigate mainly in early-middle August to early October,and about 50 to 60 days; North line of Northwest Passage was navigable mainly in September. For the Northeast Passage,the ice condition in Severnaya Zemlya,which connecting the Kara Sea and Laptev Sea,was the most complex,which was the key region determining North Passage navigable or not. The key regions affecting South line of Northwest Passage navigation were King William Island near Victoria Strait,North Peel Channel and Barrow Strait; and the key regions affecting North line of Northwest Passage were Northwest Banks Island,McClure Strait and Melville Sound. Arctic Northeast Passage is easier for navigation compared with the Northwest Passage. Sea ice extent in Arctic was reducing but the ice kinetic ability was enhanced due to sea ice thickness thinner and friable,which induced the sea ice complexity in local area. The capacity of sea ice monitoring and forecasting should be strengthened for the safety of Arctic navigation.
Using microwave satellite remote sensing data,the sea ice conditions in key regions of Arctic Northeast Passage and Northwest Passage in recent summers were analyzed and the navigable status from 2002 to 2013 were summarized. The navigable period of Northeast Passage was mainly in late August to early October,and navigable windows was 40 to 50 days; South line of Northwest Passage was free to navigate mainly in early-middle August to early October,and about 50 to 60 days; North line of Northwest Passage was navigable mainly in September. For the Northeast Passage,the ice condition in Severnaya Zemlya,which connecting the Kara Sea and Laptev Sea,was the most complex,which was the key region determining North Passage navigable or not. The key regions affecting South line of Northwest Passage navigation were King William Island near Victoria Strait,North Peel Channel and Barrow Strait; and the key regions affecting North line of Northwest Passage were Northwest Banks Island,McClure Strait and Melville Sound. Arctic Northeast Passage is easier for navigation compared with the Northwest Passage. Sea ice extent in Arctic was reducing but the ice kinetic ability was enhanced due to sea ice thickness thinner and friable,which induced the sea ice complexity in local area. The capacity of sea ice monitoring and forecasting should be strengthened for the safety of Arctic navigation.
2014, 36(10): 48-55.
doi: 10.3969/j.issn.0253-4193.2014.10.005
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Based on the data observed by drifting automatic weather station (DAWS) from August 2012 to February 2013 and NOAA re-analyzing data over the Arctic Centre,the track,movement velocity of drifting sea ice and the evolution of temperature,humidity,radiation of drifting sea ice,atmospheric processes,including the evolvement of flow pattern and temperature field and its relative dynamic and thermodynamic processes over the Arctic troposphere in 500 and 1000 hPa during period of autumn and winter around north polar are analyzed. The results show that,before 6 January 2013,sea ice moves mainly from the east to the northwest,and appearing the unstable trajectory of roundabout and turning process,then drifting towards to the south east. Its average drift velocity is 0.06 m/s,the maximum speed up to 0.4 m/s. The mutation and accelerated in the direction of polar sea ice drifting is associated with the activities of across the polar cyclone and jet stream in polar troposphere. Sea ice surface net radiation repeated short-term mutation process,resulting in the ice surface to absorb energy from the air,reduced the radiation cooling of sea ice in the Arctic area. In the autumn and winter it emerges sudden warming process in many time with the maximum increased of temperature reaches 30℃,caused conveying the warm and wet air flow. This kind of phenomenon is very rare in area of low and middle latitude. In the warming process it transports heat to the ice surface from the middle or up layer atmosphere may lead to ice floe rupture,fragile sea ice hardness,thickness of the slow growth of sea ice to accelerate the movement of the channel. This process may be one of the important mechanisms of the Arctic sea ice area and thickness reduction.
Based on the data observed by drifting automatic weather station (DAWS) from August 2012 to February 2013 and NOAA re-analyzing data over the Arctic Centre,the track,movement velocity of drifting sea ice and the evolution of temperature,humidity,radiation of drifting sea ice,atmospheric processes,including the evolvement of flow pattern and temperature field and its relative dynamic and thermodynamic processes over the Arctic troposphere in 500 and 1000 hPa during period of autumn and winter around north polar are analyzed. The results show that,before 6 January 2013,sea ice moves mainly from the east to the northwest,and appearing the unstable trajectory of roundabout and turning process,then drifting towards to the south east. Its average drift velocity is 0.06 m/s,the maximum speed up to 0.4 m/s. The mutation and accelerated in the direction of polar sea ice drifting is associated with the activities of across the polar cyclone and jet stream in polar troposphere. Sea ice surface net radiation repeated short-term mutation process,resulting in the ice surface to absorb energy from the air,reduced the radiation cooling of sea ice in the Arctic area. In the autumn and winter it emerges sudden warming process in many time with the maximum increased of temperature reaches 30℃,caused conveying the warm and wet air flow. This kind of phenomenon is very rare in area of low and middle latitude. In the warming process it transports heat to the ice surface from the middle or up layer atmosphere may lead to ice floe rupture,fragile sea ice hardness,thickness of the slow growth of sea ice to accelerate the movement of the channel. This process may be one of the important mechanisms of the Arctic sea ice area and thickness reduction.
2014, 36(10): 56-60.
doi: 10.3969/j.issn.0253-4193.2014.10.006
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Mohns ridge in the north of Atlantic Ocean is a very important expansive band. One of the key for the Fifth Chinese National Arctic Research Expedition is to acquire the magnetic data on Mohns ridge. According to the magnetic,gravity and seismic data,the Mohns ridge expansion,characteristics of crustal structure and thickness are researched. These studies contribute to better understanding of the earth's geological process,seafloor spreading and crust mantle.
Mohns ridge in the north of Atlantic Ocean is a very important expansive band. One of the key for the Fifth Chinese National Arctic Research Expedition is to acquire the magnetic data on Mohns ridge. According to the magnetic,gravity and seismic data,the Mohns ridge expansion,characteristics of crustal structure and thickness are researched. These studies contribute to better understanding of the earth's geological process,seafloor spreading and crust mantle.
2014, 36(10): 61-68.
doi: 10.3969/j.issn.0253-4193.2014.10.007
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High resolution single channel seismic operation was carried out in the Bering Sea during the 5th Chinese National Expedition. Asymmetric sand waves were identified on line BL11-12 seismic profile in the head of Navarinsky Canyon. The steep faces of asymmetric sand waves were on-shelf direction, the averaged wave height was 9 m and length was 882 m. There was a sedimentary depression at the end of line BL11-12 seismic profile. Combined the sedimentation rate of site U1345 and Vp of superficial sediment at site U1344, Infered that sand waves began deposit and sedimentary depression was filled since the Middle Pleistocene(about 0.258 Ma). Stratum was divided into three sediments. Analyzing changes of grain size on the profile, we can speculate the surface relating to the maximum regression combined with the change of the bering sea level. Taking every aspect into consideration, draw conclusion that sand waves formed during the low sea level in Middle Pleistocene, and internal wave played a significant role.
High resolution single channel seismic operation was carried out in the Bering Sea during the 5th Chinese National Expedition. Asymmetric sand waves were identified on line BL11-12 seismic profile in the head of Navarinsky Canyon. The steep faces of asymmetric sand waves were on-shelf direction, the averaged wave height was 9 m and length was 882 m. There was a sedimentary depression at the end of line BL11-12 seismic profile. Combined the sedimentation rate of site U1345 and Vp of superficial sediment at site U1344, Infered that sand waves began deposit and sedimentary depression was filled since the Middle Pleistocene(about 0.258 Ma). Stratum was divided into three sediments. Analyzing changes of grain size on the profile, we can speculate the surface relating to the maximum regression combined with the change of the bering sea level. Taking every aspect into consideration, draw conclusion that sand waves formed during the low sea level in Middle Pleistocene, and internal wave played a significant role.
2014, 36(10): 69-79.
doi: 10.3969/j.issn.0253-4193.2014.10.008
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On the basis of high-resolution bathymetry,gravity,magnetic and multi-channel reflection seismic data,the geomorphology and geophysical characteristic of the Chukchi Borderland and its adjacent area was synthetically analyzed and the tectonic division was made. The results shows that the Chukchi Borderland is a relatively isolated tectonic unit and has different geophysical and structural features from the peripheral units,they are Canada Oceanic Basin,Alpha-Mendeleev Large Igneous Province,North Chukchi Continental Shelf Basin and Alaska Passive Continental Margin. Chukchi Borderland is a micro-continental plate with thinned crust,where a large scale E-W oriented tectonic stretching had happened during the early and middle stage of the Cenozoic. Basement uplifting and subsiding is the controlling factor of the modern geomorphic features and sediments accumulation. The Chukchi micro-continental plate was supposed to result from the rifting process of the North Chukchi Basin in Jurassic to early Cretaceous Period,while its modern tectonic framework with juxtaposition of basins and ridges might be the result of isostatic regulation after the cease of subduction of oceanic crust in Canada Basin to the Borderland.
On the basis of high-resolution bathymetry,gravity,magnetic and multi-channel reflection seismic data,the geomorphology and geophysical characteristic of the Chukchi Borderland and its adjacent area was synthetically analyzed and the tectonic division was made. The results shows that the Chukchi Borderland is a relatively isolated tectonic unit and has different geophysical and structural features from the peripheral units,they are Canada Oceanic Basin,Alpha-Mendeleev Large Igneous Province,North Chukchi Continental Shelf Basin and Alaska Passive Continental Margin. Chukchi Borderland is a micro-continental plate with thinned crust,where a large scale E-W oriented tectonic stretching had happened during the early and middle stage of the Cenozoic. Basement uplifting and subsiding is the controlling factor of the modern geomorphic features and sediments accumulation. The Chukchi micro-continental plate was supposed to result from the rifting process of the North Chukchi Basin in Jurassic to early Cretaceous Period,while its modern tectonic framework with juxtaposition of basins and ridges might be the result of isostatic regulation after the cease of subduction of oceanic crust in Canada Basin to the Borderland.
2014, 36(10): 80-89.
doi: 10.3969/j.issn.0253-4193.2014.10.009
Abstract:
Kongsfjorden is located in the northwest of Svalbard,Arctic,and the water is affected by Arctic glacier and the Atlantic Ocean. In order to study the affects of glacier water and Atlantic water on distribution of nutrients and the ecosystem in Kongsfjorden,seawater and runoff water were sampled and analyzed for the nutrients and Chlorophyll a during the Yellow River Station expedition in summer 2010. The results showed that,it was a weak year of the Atlantic water in kongsfjorden 2010,and the transformed local water with low temperature,low salinity and high nutrients was in control. The Kongsfjorden water in July 2010 could be divided into 4 water masses,including surface water (SW),transformed intermediate water (TIW),transformed local water (TLW) and transformed Atlantic water (TAW),of which,the nutrient concentration were low in SW and TIW,while,as the depth went deeper,nutrient concentrations were higher in TLW and TAW. The water column below 200 m was mainly controlled by TAW,and its nutrient concentration was lower than those in the bottom of TLW. The higher nutrients of TLW were mainly derived from the nutrient regeneration of the particulates in the water column. The glacier melting water and runoff water controlled the SW,and these freshwater inputs and the primary production of the phytoplankton together determined the nutrient concentrations and structures in SW. In the water column at about 100 m of TLW,the high ammonia concentration was connected with the metabolic processes of the zooplankton and/or microorganism.
Kongsfjorden is located in the northwest of Svalbard,Arctic,and the water is affected by Arctic glacier and the Atlantic Ocean. In order to study the affects of glacier water and Atlantic water on distribution of nutrients and the ecosystem in Kongsfjorden,seawater and runoff water were sampled and analyzed for the nutrients and Chlorophyll a during the Yellow River Station expedition in summer 2010. The results showed that,it was a weak year of the Atlantic water in kongsfjorden 2010,and the transformed local water with low temperature,low salinity and high nutrients was in control. The Kongsfjorden water in July 2010 could be divided into 4 water masses,including surface water (SW),transformed intermediate water (TIW),transformed local water (TLW) and transformed Atlantic water (TAW),of which,the nutrient concentration were low in SW and TIW,while,as the depth went deeper,nutrient concentrations were higher in TLW and TAW. The water column below 200 m was mainly controlled by TAW,and its nutrient concentration was lower than those in the bottom of TLW. The higher nutrients of TLW were mainly derived from the nutrient regeneration of the particulates in the water column. The glacier melting water and runoff water controlled the SW,and these freshwater inputs and the primary production of the phytoplankton together determined the nutrient concentrations and structures in SW. In the water column at about 100 m of TLW,the high ammonia concentration was connected with the metabolic processes of the zooplankton and/or microorganism.
2014, 36(10): 90-102.
doi: 10.3969/j.issn.0253-4193.2014.10.010
Abstract:
On the basis of the measured oxygen isotopic composition of seawater,the S and δ18O mass balance was employed to determine the fraction of river water and sea-ice melted water in Chukchi Sea in summer 2008. The spatial patterns of river water and sea-ice melted water were revealed and the affecting factors were disccussed. The fractions of river water decreased with the increasing depth,with a range from 1.9% to 18.4%. The integrated heights of river water (IfR) were 1.3~16.6 m,with an average of (4.8±4.0)m. IfR showed a spatial characteristic with high values in the east and north and low values in the west and south. This spatial variation of river water was ascribed to the difference amount of river water carried by the Pacific inflows (e.g.,high river water components in the Alaska Current Water and low river water components in the Bering Shelf water),the pathway of the Pacific inflows and the Ekman pumping of Beaufort Gyre. The fractions of sea-ice melted water decreased dramaticly with the increasing depth. A negative value was observed at depth of about 20 m to 30 m. The integrated heights of sea-ice melted water (IfI) were from -3.2 m to 1.7 m,with an average of (0.3±1.2)m. IfI was higher in the west and south,but lower in the east and north. The spatial variation of sea-ice melted water was attributed to the strength and time of the Pacific inflows,as well as the topographically impact which diverted the Pacific inflow westward.
On the basis of the measured oxygen isotopic composition of seawater,the S and δ18O mass balance was employed to determine the fraction of river water and sea-ice melted water in Chukchi Sea in summer 2008. The spatial patterns of river water and sea-ice melted water were revealed and the affecting factors were disccussed. The fractions of river water decreased with the increasing depth,with a range from 1.9% to 18.4%. The integrated heights of river water (IfR) were 1.3~16.6 m,with an average of (4.8±4.0)m. IfR showed a spatial characteristic with high values in the east and north and low values in the west and south. This spatial variation of river water was ascribed to the difference amount of river water carried by the Pacific inflows (e.g.,high river water components in the Alaska Current Water and low river water components in the Bering Shelf water),the pathway of the Pacific inflows and the Ekman pumping of Beaufort Gyre. The fractions of sea-ice melted water decreased dramaticly with the increasing depth. A negative value was observed at depth of about 20 m to 30 m. The integrated heights of sea-ice melted water (IfI) were from -3.2 m to 1.7 m,with an average of (0.3±1.2)m. IfI was higher in the west and south,but lower in the east and north. The spatial variation of sea-ice melted water was attributed to the strength and time of the Pacific inflows,as well as the topographically impact which diverted the Pacific inflow westward.
2014, 36(10): 103-115.
doi: 10.3969/j.issn.0253-4193.2014.10.011
Abstract:
Size fractionated standing stock and primary production of phytoplankton in the Chukchi Sea and the adjacent sea area were studied during the 5th Chinese National Arctic Research Expedition in the summer of 2012. The results clearly showed that there was marked feature of spatial zonation in the sea areas investigated. In the shelf region, the standing stock and primary production were much higher than those of deep-sea area. The water column integrated average values of Chl a concentration varied from 0.32 to 15.66 mg/m3 [on average (2.77±3.96)mg/m3] during the outward voyage. The high values appeared in the southern Chukchi Sea, coast areas near Point Barrow of Alaska and northern ice edge area. The lowest and highest value of primary production (PP) were 50.11 mg/(m2·d) and 943.28 mg/(m2·d), and the high value was encountered in the ice edge where phytoplankton bloom happened. During the return voyage, the water column integrated average value of Chl a concentration was an order of magnitude lower than the outward voyage. The values of PP were 12.31~41.35 mg/(m2·d), with the high value appearing in the shelf region. The results of size-fractionated Chl a and PP showed that photosynthetic picoplankton was the greatest contributor to phytoplankton stocks and production in deep-sea area (46.1% and 56.9% respectively), and the differences between contributions of microplankton and nanoplankton to Chl a and PP were very small. But in the shelf region, microplankton took the dominant position of Chl a(59.8%) and PP (60.6%), picoplankton second and nanoplankton the minimum.
Size fractionated standing stock and primary production of phytoplankton in the Chukchi Sea and the adjacent sea area were studied during the 5th Chinese National Arctic Research Expedition in the summer of 2012. The results clearly showed that there was marked feature of spatial zonation in the sea areas investigated. In the shelf region, the standing stock and primary production were much higher than those of deep-sea area. The water column integrated average values of Chl a concentration varied from 0.32 to 15.66 mg/m3 [on average (2.77±3.96)mg/m3] during the outward voyage. The high values appeared in the southern Chukchi Sea, coast areas near Point Barrow of Alaska and northern ice edge area. The lowest and highest value of primary production (PP) were 50.11 mg/(m2·d) and 943.28 mg/(m2·d), and the high value was encountered in the ice edge where phytoplankton bloom happened. During the return voyage, the water column integrated average value of Chl a concentration was an order of magnitude lower than the outward voyage. The values of PP were 12.31~41.35 mg/(m2·d), with the high value appearing in the shelf region. The results of size-fractionated Chl a and PP showed that photosynthetic picoplankton was the greatest contributor to phytoplankton stocks and production in deep-sea area (46.1% and 56.9% respectively), and the differences between contributions of microplankton and nanoplankton to Chl a and PP were very small. But in the shelf region, microplankton took the dominant position of Chl a(59.8%) and PP (60.6%), picoplankton second and nanoplankton the minimum.
2014, 36(10): 116-123.
doi: 10.3969/j.issn.0253-4193.2014.10.012
Abstract:
Culturable bacteria were isolated by use of marine Zobell 2216E medium and spread plate method. Molecular identification and phylogenetic analysis were carried out on the basis of 16S rRNA gene. According to the distinct morphological character of bacterial colony on the marine Zobell 2216E medium plate,a total of 570 isolates were obtained from Arctic sediments. Molecular identification and phylogenetic analysis showed that these isolates belonged to four phylum of the bacteria domain,5 classes,47 genera,and 102 species in total. 14 isolates had 16S rRNA gene similarity less than 97% with the closest type strain were grouped into 6 clusters. It indicated that these isolates might be potential novel species. A high diversity of culturable bacteria were isolated from marine sediment of Arctic in term of both species number and phylogenetic composition,which deserves further study and exploitation,such as novel bioactive substances and functional genes.
Culturable bacteria were isolated by use of marine Zobell 2216E medium and spread plate method. Molecular identification and phylogenetic analysis were carried out on the basis of 16S rRNA gene. According to the distinct morphological character of bacterial colony on the marine Zobell 2216E medium plate,a total of 570 isolates were obtained from Arctic sediments. Molecular identification and phylogenetic analysis showed that these isolates belonged to four phylum of the bacteria domain,5 classes,47 genera,and 102 species in total. 14 isolates had 16S rRNA gene similarity less than 97% with the closest type strain were grouped into 6 clusters. It indicated that these isolates might be potential novel species. A high diversity of culturable bacteria were isolated from marine sediment of Arctic in term of both species number and phylogenetic composition,which deserves further study and exploitation,such as novel bioactive substances and functional genes.
2014, 36(10): 124-130.
doi: 10.3969/j.issn.0253-4193.2014.10.013
Abstract:
In order to explore the diversity of fungi in the Arctic land and reveal their ecological roles, fungi were isolated and identified from 24 samples collected from Yellow River Station during the 5th Chinese Artic Scientific Expedition in the present study. Sixty strains of fungi were totally isolated by plate spreading and streaking. More fungal species and quantity were isolated in humus than in other samples. Classification and phylogenetic analysis based on ITS rDNA showed that 28 representative fungal strains belonged to 4 classes, including Eurotiomycetes, Sordariomycetes, Dothideomycetes and Phycomycetes, and 12 genus. Geomyces was one of the most dominant genera among them. The data indicated that abundant fungal diversity existed in Arctic. The relationship between physicochemical parameters of soil and fungal diversity was explored through determination of physical and chemical properties of the representative soil. The organic carbon and nitrogen and soluble nutrient content are important factors affecting the fungal diversity in Arctic.
In order to explore the diversity of fungi in the Arctic land and reveal their ecological roles, fungi were isolated and identified from 24 samples collected from Yellow River Station during the 5th Chinese Artic Scientific Expedition in the present study. Sixty strains of fungi were totally isolated by plate spreading and streaking. More fungal species and quantity were isolated in humus than in other samples. Classification and phylogenetic analysis based on ITS rDNA showed that 28 representative fungal strains belonged to 4 classes, including Eurotiomycetes, Sordariomycetes, Dothideomycetes and Phycomycetes, and 12 genus. Geomyces was one of the most dominant genera among them. The data indicated that abundant fungal diversity existed in Arctic. The relationship between physicochemical parameters of soil and fungal diversity was explored through determination of physical and chemical properties of the representative soil. The organic carbon and nitrogen and soluble nutrient content are important factors affecting the fungal diversity in Arctic.
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