2015 Vol. 37, No. 10
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2015, 37(10): .
Abstract:
2015, 37(10): 1-10.
doi: 10.3969/j.issn.0253-4193.2015.10.001
Abstract:
Deep submergence technology is the cutting edge and one of the most advanced deep-sea technologies. With the development of high technology since 1960s,countries such as America,Japan,France and Russia have made a rapid progress in the development and application of manned submersibles; they have mastered this technology successively and are capable of applying it to the in situ observation,detection and sampling at complex deep ocean conditions. To date,the vehicles have been applied to obtain deep-sea geological,geophysical,biological,chemical and environmental information at areas including continental slopes,mid-ocean ridges,seamounts,sea-floor trenches and ocean basins all over the world,based on which,a batch of important findings and innovative results have been achieved and thus improving the deep sea research. China self-designed Jiaolong manned submersible has successfully completed 7 000 m class sea trial. The test operational phase has been conducted since 2013,and rich scientific investigations have been achieved via the successful voyages. This paper briefly describes the current status of the development of manned submersibles of each country and their advantages in deep ocean research,and reviews the application in marine geology,biology and physical oceanography of manned submersibles developed by domestic and foreign countries.
Deep submergence technology is the cutting edge and one of the most advanced deep-sea technologies. With the development of high technology since 1960s,countries such as America,Japan,France and Russia have made a rapid progress in the development and application of manned submersibles; they have mastered this technology successively and are capable of applying it to the in situ observation,detection and sampling at complex deep ocean conditions. To date,the vehicles have been applied to obtain deep-sea geological,geophysical,biological,chemical and environmental information at areas including continental slopes,mid-ocean ridges,seamounts,sea-floor trenches and ocean basins all over the world,based on which,a batch of important findings and innovative results have been achieved and thus improving the deep sea research. China self-designed Jiaolong manned submersible has successfully completed 7 000 m class sea trial. The test operational phase has been conducted since 2013,and rich scientific investigations have been achieved via the successful voyages. This paper briefly describes the current status of the development of manned submersibles of each country and their advantages in deep ocean research,and reviews the application in marine geology,biology and physical oceanography of manned submersibles developed by domestic and foreign countries.
2015, 37(10): 11-25.
doi: 10.3969/j.issn.0253-4193.2015.10.002
Abstract:
Lack of accurate multi-beam bathymetric data,publications on meticulous characteristics of sand wave on Taiwan bank are rare. For this reason,the paper presents an approach to objectively analyze large number of sand waves on their meticulous shape characteristics and distribution using multi-beam bathymetric data. The results show that the average of wavelength of sand wave is up to 13.5 m,which is the about 2/3 of the depth of the water,the depth is 20.42 m at the crest of sand wave and the range of the wavelength is almost between 500 m and 700 m. Three types of sand wave are found,which are trochoidal sand wave,sinusoidal sand wave and bimodal sand wave. The occurrence on the west of the bank is bimodal sand wave,the middle is trochoidal sand wave and sinusoidal sand wave. The whole of bank is almost trochoidal sand wave. The influence factors of sand wave are variation of sea level,the long-term sediment flux from Western Taiwanese rivers and hydrodynamic in Taiwan Bank.
Lack of accurate multi-beam bathymetric data,publications on meticulous characteristics of sand wave on Taiwan bank are rare. For this reason,the paper presents an approach to objectively analyze large number of sand waves on their meticulous shape characteristics and distribution using multi-beam bathymetric data. The results show that the average of wavelength of sand wave is up to 13.5 m,which is the about 2/3 of the depth of the water,the depth is 20.42 m at the crest of sand wave and the range of the wavelength is almost between 500 m and 700 m. Three types of sand wave are found,which are trochoidal sand wave,sinusoidal sand wave and bimodal sand wave. The occurrence on the west of the bank is bimodal sand wave,the middle is trochoidal sand wave and sinusoidal sand wave. The whole of bank is almost trochoidal sand wave. The influence factors of sand wave are variation of sea level,the long-term sediment flux from Western Taiwanese rivers and hydrodynamic in Taiwan Bank.
2015, 37(10): 26-38.
doi: 10.3969/j.issn.0253-4193.2015.10.003
Abstract:
On the basis of satellite remotely sensed monthly chlorophyll a concentration and particle backscattering coefficient,as well as other oceanographic and meteorological parameters,this study analyzed on the correlation coefficients between concentration of chlorophyll a and particulate backscattering on seasonal scale and their coupling relationships with physical parameters in the South China Sea. In addition,a phytoplankton photoacclimation model was utilized to identify the physiological characteristics. The results showed that,due to the influences of specific topography,wind forcing and other physical parameters,both consistency and discrepancy between the seasonal cycles of chlorophyll a and particle backscattering coefficient were found in the South China Sea. In coastal and shallow waters,two properties were strongly coupled; while in the central deep-water basin,chlorophyll a was higher in winter and lower in summer,totally differing from the seasonal evolution of particles,such phenomenon was mainly owing to phytoplankton physiological process. The boundary of "biomass regime" and "photoacclimation regime" in the South China Sea located at the shelf-basin interface,suggesting the influence of water depth on the phytoplankton physiological status. Furthermore,a characteristics of "biomass-photoacclimation joint controlling" was found in the west of Luzon Strait.
On the basis of satellite remotely sensed monthly chlorophyll a concentration and particle backscattering coefficient,as well as other oceanographic and meteorological parameters,this study analyzed on the correlation coefficients between concentration of chlorophyll a and particulate backscattering on seasonal scale and their coupling relationships with physical parameters in the South China Sea. In addition,a phytoplankton photoacclimation model was utilized to identify the physiological characteristics. The results showed that,due to the influences of specific topography,wind forcing and other physical parameters,both consistency and discrepancy between the seasonal cycles of chlorophyll a and particle backscattering coefficient were found in the South China Sea. In coastal and shallow waters,two properties were strongly coupled; while in the central deep-water basin,chlorophyll a was higher in winter and lower in summer,totally differing from the seasonal evolution of particles,such phenomenon was mainly owing to phytoplankton physiological process. The boundary of "biomass regime" and "photoacclimation regime" in the South China Sea located at the shelf-basin interface,suggesting the influence of water depth on the phytoplankton physiological status. Furthermore,a characteristics of "biomass-photoacclimation joint controlling" was found in the west of Luzon Strait.
2015, 37(10): 39-48.
doi: 10.3969/j.issn.0253-4193.2015.10.004
Abstract:
To improve the accuracy of fishing ground forecasting of chub mackerel (Scomber japonicus) in the Yellow and East China Sea,and reduce the fishery production cost,a new fishing ground forecasting model based on boosted regression trees was proposed in this study. Model was fitted with data extracted from electronic logbooks of Chinese mainland large-type lighting purse seine fishery for chub mackerel,with a range from 2003 to 2010. The fishing area with fishing effort was identified as fishing ground and the pseudo non fishing ground data was randomly collected from background field,which is the fishing areas with no records in the logbooks. The predictive variables were sea surface temperature and other environmental factors. The performance of prediction of the model was evaluated with the testing dataset consist of actual fishing locations of year 2011. The results of the evaluation showed that the prediction model had a high prediction performance with an AUC value of 0.897. The results of spatial prediction showed that the predicted fishing ground and its shifting were coincided with the actual fishing locations,which indicated that the forecasting model based on boosted regression trees can be used to forecasting the fishing ground of chub mackerel in the Yellow and East China Sea.
To improve the accuracy of fishing ground forecasting of chub mackerel (Scomber japonicus) in the Yellow and East China Sea,and reduce the fishery production cost,a new fishing ground forecasting model based on boosted regression trees was proposed in this study. Model was fitted with data extracted from electronic logbooks of Chinese mainland large-type lighting purse seine fishery for chub mackerel,with a range from 2003 to 2010. The fishing area with fishing effort was identified as fishing ground and the pseudo non fishing ground data was randomly collected from background field,which is the fishing areas with no records in the logbooks. The predictive variables were sea surface temperature and other environmental factors. The performance of prediction of the model was evaluated with the testing dataset consist of actual fishing locations of year 2011. The results of the evaluation showed that the prediction model had a high prediction performance with an AUC value of 0.897. The results of spatial prediction showed that the predicted fishing ground and its shifting were coincided with the actual fishing locations,which indicated that the forecasting model based on boosted regression trees can be used to forecasting the fishing ground of chub mackerel in the Yellow and East China Sea.
2015, 37(10): 49-58.
doi: 10.3969/j.issn.0253-4193.2015.10.005
Abstract:
Dosidicus gigas is one of the important economic cephalopod in the world. It is widely distributed in the east of Pacific Ocean. Nowadays the yield of Dosidicus gigas occupies more than 50% of the total yield of squid in China mainland. In 2012 ,the yearly catch in China mainland reached 221.1 thousand tons,the number of fishing vessels are more than 250. It is necessary to assess the stock for making the fishery sustainable. Unfortunately little work is done in this field.The stock assessment and risk analysis of alternative management strategies for Dosidicus gigas in the Southeast Pacific Ocean were carried out by using a Bayesian Schaefer model,in which two scenarios,standard scenario and sensitivity analysis scenario,are considered.The Schaefer model was chosen because of the lack of age-data of Dosidicus gigas and also because the migration mechanism and stock structure of the squid was very complex which was not completely understood by us. In many cases,Schaefer model performed better than many other more complex models such as age-data based models or metapopulation model. For parameters K and q in standard scenario,the posterior distribution are approximately normal distributed. It is totally different with the prior distribution which is set to be uniform distribution. Compared with the two scenarios,the results of posterior distribution of the three parameters are similar .The study indicated that the data of yearly yield and CPUE provided sufficient information for the valuation of model parameters. Under standard scenario,the MSY (maximum sustainable yield)is 1.429 million tons. To maintain MSY,the biomass and fishing mortality should be 2.147 million tons and 0.682,respectively. Under sensitivity analysis scenario,the MSY is 1.525 million tons. To maintain MSY,the biomass and fishing mortality should be 2.296 million tons and 0.691,respectively. Under both scenarios,the fishing mortalities and yearly catches from 2003 to 2012 were lower than reference points F0.1 and MSY,and the biomass was greater than target reference point Bmsy. Status of resource was good and it was not suffering overexploiting or exploited. We set 7 indexes to evaluate alternative strategies and simulated 1 000 times for every single harvest rates from 0.1 to 0.8. Strategy and risk analysis indicated that when the harvest rate was up to 0.7,the average yearly catches would be decreasing. And when the harvest rate was set below 0.3,the resource could be well protected and the probability of resource collapse would be very low. It is concluded that the harvest rate of 0.3 appears to be the best management regulation and the MSY will attain at 990 thousand tons. The harvest rate from 2003 to 2012 were all below 0.3,it was a reason for us to be optimistic for this potential resource. However there were many uncertainty factors in the simulation which should be considered in future studies.
Dosidicus gigas is one of the important economic cephalopod in the world. It is widely distributed in the east of Pacific Ocean. Nowadays the yield of Dosidicus gigas occupies more than 50% of the total yield of squid in China mainland. In 2012 ,the yearly catch in China mainland reached 221.1 thousand tons,the number of fishing vessels are more than 250. It is necessary to assess the stock for making the fishery sustainable. Unfortunately little work is done in this field.The stock assessment and risk analysis of alternative management strategies for Dosidicus gigas in the Southeast Pacific Ocean were carried out by using a Bayesian Schaefer model,in which two scenarios,standard scenario and sensitivity analysis scenario,are considered.The Schaefer model was chosen because of the lack of age-data of Dosidicus gigas and also because the migration mechanism and stock structure of the squid was very complex which was not completely understood by us. In many cases,Schaefer model performed better than many other more complex models such as age-data based models or metapopulation model. For parameters K and q in standard scenario,the posterior distribution are approximately normal distributed. It is totally different with the prior distribution which is set to be uniform distribution. Compared with the two scenarios,the results of posterior distribution of the three parameters are similar .The study indicated that the data of yearly yield and CPUE provided sufficient information for the valuation of model parameters. Under standard scenario,the MSY (maximum sustainable yield)is 1.429 million tons. To maintain MSY,the biomass and fishing mortality should be 2.147 million tons and 0.682,respectively. Under sensitivity analysis scenario,the MSY is 1.525 million tons. To maintain MSY,the biomass and fishing mortality should be 2.296 million tons and 0.691,respectively. Under both scenarios,the fishing mortalities and yearly catches from 2003 to 2012 were lower than reference points F0.1 and MSY,and the biomass was greater than target reference point Bmsy. Status of resource was good and it was not suffering overexploiting or exploited. We set 7 indexes to evaluate alternative strategies and simulated 1 000 times for every single harvest rates from 0.1 to 0.8. Strategy and risk analysis indicated that when the harvest rate was up to 0.7,the average yearly catches would be decreasing. And when the harvest rate was set below 0.3,the resource could be well protected and the probability of resource collapse would be very low. It is concluded that the harvest rate of 0.3 appears to be the best management regulation and the MSY will attain at 990 thousand tons. The harvest rate from 2003 to 2012 were all below 0.3,it was a reason for us to be optimistic for this potential resource. However there were many uncertainty factors in the simulation which should be considered in future studies.
2015, 37(10): 59-68.
doi: 10.3969/j.issn.0253-4193.2015.10.006
Abstract:
Since the industrial revolution,large amounts of CO2 released by human activities into the atmosphere not only produce serious greenhouse effect,but also cause ocean acidification (OA). Reef-building corals are thought to the most sensitive to ocean acidification. Ocean acidification is predicted to impact the physiology of corals and reduce the calcification rates. In the present study,the calcification and photosynthesis capacity (Fv/Fm) of hermatypic coral Pocillopora damicornis was measured to study the physiological effect of OA by the simulation of further scenario of ocean acidification based on the gas exchange method. The experiment was conducted for 5 weeks in natural light with the seawater temperature controlled at 27.5℃ (±1℃) by the chiller. Two pH values (7.8 and 8.1,respectively) were set by pH regulation,which mediate the CO2 gas into experimental seawater. The diurnal variation of pH during the experiment was observed,with the pH values varied from 7.69 to 7.91 for the OA treatment and from 7.99 to 8.29 for the control due to the metabolic process (mainly respiration from the organisms). The results showed that the calcification rate of P. damicornis ranged from 1.15%~2.09%·week-1,and no significant difference was found in calcification and Fv/Fm between OA treatment and the control,indicating the low sensitivity of P. damicornis to OA. Compared to those previous publications,species-specific responses were further confirmed facing to OA. It is speculated that the tolerance of P. damicornis to OA may be due to the use of HCO3- in the light and up-regulation of pH in at their site of calcification. The capacity to up-regulate pH may be central to the resilience of P. damicornis to OA because the buffer capacity of pH can maintain relatively high the saturation of aragonite at their site of calcification and thus the calcification of corals at relatively low cost.
Since the industrial revolution,large amounts of CO2 released by human activities into the atmosphere not only produce serious greenhouse effect,but also cause ocean acidification (OA). Reef-building corals are thought to the most sensitive to ocean acidification. Ocean acidification is predicted to impact the physiology of corals and reduce the calcification rates. In the present study,the calcification and photosynthesis capacity (Fv/Fm) of hermatypic coral Pocillopora damicornis was measured to study the physiological effect of OA by the simulation of further scenario of ocean acidification based on the gas exchange method. The experiment was conducted for 5 weeks in natural light with the seawater temperature controlled at 27.5℃ (±1℃) by the chiller. Two pH values (7.8 and 8.1,respectively) were set by pH regulation,which mediate the CO2 gas into experimental seawater. The diurnal variation of pH during the experiment was observed,with the pH values varied from 7.69 to 7.91 for the OA treatment and from 7.99 to 8.29 for the control due to the metabolic process (mainly respiration from the organisms). The results showed that the calcification rate of P. damicornis ranged from 1.15%~2.09%·week-1,and no significant difference was found in calcification and Fv/Fm between OA treatment and the control,indicating the low sensitivity of P. damicornis to OA. Compared to those previous publications,species-specific responses were further confirmed facing to OA. It is speculated that the tolerance of P. damicornis to OA may be due to the use of HCO3- in the light and up-regulation of pH in at their site of calcification. The capacity to up-regulate pH may be central to the resilience of P. damicornis to OA because the buffer capacity of pH can maintain relatively high the saturation of aragonite at their site of calcification and thus the calcification of corals at relatively low cost.
2015, 37(10): 69-79.
doi: 10.3969/j.issn.0253-4193.2015.10.007
Abstract:
The young gametophytic blades of Pyropia dentata, developed from conchospores of the wild-type strain (PD-WT), were treated with 60Co-γ ray to induce mutation in the experiment. After being cultured for 4 weeks, there were many color-mutated cell clusters showing bright red, red brown, red orange and yellow green in the treated blades. The results showed that the percentage of the colored-mutated cell-clusters increased as increasing of the irradiation dose and from the base to the tip of the blades. Single color-mutated cells were isolated enzymatically from the color-mutated blades and were regenerated into blades. An improved strain named as PD-5 strain with the growth advantages was selected from the regenerated blades. In the growth of the blades, the maximum and average absolute growth rates of this improved strain were 3.76 cm/d and 2.71 cm/d, which were 3.60 and 4.22 times that of the PD-WT strain, respectively, during culture from 30 to 70 days. The mean length of F1 gametophytic blades of PD-5 strain was 117.42 cm which was 4.32 times that of the PD-WT strain after being cultured for 70 days. The contents of Chl a and phycobiliprotein of thePD-5 strain were 8.41 mg/g and 97.07 mg/g, respectively, increasing by 25.71% and 104.44% in contrast with that of the PD-WT,respectively. The mean thickness of the 45-day-old blades of the PD-5 was 26.79 μm,decreasing by 35.04% in contrast with that of the PD-WT. The total numbers of the conchospores released from the PD- 5 strain was 421.16×104 per shell,which was 2.19 times that of the PD-WT strain. The aboved results confirmed that the PD-5 strain was characterized by faster growth,higher contents of photosynthetic pigments,larger amount of releasing conchospores than the wild-type strain. Therefore,the improved strain PD-5 had great potential to be applied in commercial cultivation as a new strain.
The young gametophytic blades of Pyropia dentata, developed from conchospores of the wild-type strain (PD-WT), were treated with 60Co-γ ray to induce mutation in the experiment. After being cultured for 4 weeks, there were many color-mutated cell clusters showing bright red, red brown, red orange and yellow green in the treated blades. The results showed that the percentage of the colored-mutated cell-clusters increased as increasing of the irradiation dose and from the base to the tip of the blades. Single color-mutated cells were isolated enzymatically from the color-mutated blades and were regenerated into blades. An improved strain named as PD-5 strain with the growth advantages was selected from the regenerated blades. In the growth of the blades, the maximum and average absolute growth rates of this improved strain were 3.76 cm/d and 2.71 cm/d, which were 3.60 and 4.22 times that of the PD-WT strain, respectively, during culture from 30 to 70 days. The mean length of F1 gametophytic blades of PD-5 strain was 117.42 cm which was 4.32 times that of the PD-WT strain after being cultured for 70 days. The contents of Chl a and phycobiliprotein of thePD-5 strain were 8.41 mg/g and 97.07 mg/g, respectively, increasing by 25.71% and 104.44% in contrast with that of the PD-WT,respectively. The mean thickness of the 45-day-old blades of the PD-5 was 26.79 μm,decreasing by 35.04% in contrast with that of the PD-WT. The total numbers of the conchospores released from the PD- 5 strain was 421.16×104 per shell,which was 2.19 times that of the PD-WT strain. The aboved results confirmed that the PD-5 strain was characterized by faster growth,higher contents of photosynthetic pigments,larger amount of releasing conchospores than the wild-type strain. Therefore,the improved strain PD-5 had great potential to be applied in commercial cultivation as a new strain.
2015, 37(10): 80-87.
doi: 10.3969/j.issn.0253-4193.2015.10.008
Abstract:
Ocean acidification due to increasing anthropogenic CO2 is expected to influence marine primary productivity. In order to investigate the interactive effects of increased light and CO2 changes on macroalgae,we grew Ulva prolifera seedling under the normal CO2 level (400 μL/L) and elevated CO2 level (1 000 μL/L) conditions,the light levels set as 80 and 260 μmol/(m2·s),and measured its physiological performance. Research finding that the specific growth rate and activity of SOD was highest under high light and normal CO2 level . However,the activity of CAT showed the highest value under the high CO2 and low light conditions. Under the different treatments,there was no significant effect on the chlorophyll a and maximal photochemical yield of PSⅡ (Fv/Fm),while the largest ratios of chlorophylla to carotenoid occurred at nomal CO2 and low light conditions. Meanwhile,the content of soluble protein was decreased by high light and high CO2.
Ocean acidification due to increasing anthropogenic CO2 is expected to influence marine primary productivity. In order to investigate the interactive effects of increased light and CO2 changes on macroalgae,we grew Ulva prolifera seedling under the normal CO2 level (400 μL/L) and elevated CO2 level (1 000 μL/L) conditions,the light levels set as 80 and 260 μmol/(m2·s),and measured its physiological performance. Research finding that the specific growth rate and activity of SOD was highest under high light and normal CO2 level . However,the activity of CAT showed the highest value under the high CO2 and low light conditions. Under the different treatments,there was no significant effect on the chlorophyll a and maximal photochemical yield of PSⅡ (Fv/Fm),while the largest ratios of chlorophylla to carotenoid occurred at nomal CO2 and low light conditions. Meanwhile,the content of soluble protein was decreased by high light and high CO2.
2015, 37(10): 88-99.
doi: 10.3969/j.issn.0253-4193.2015.10.009
Abstract:
In situ survey of northeastern South China Sea (20°~24°N,114°~121°E),combined with nutrient (Nitrogen and Phosphorus) enrichment experiments were conducted during a cruise of Shiyan Ⅲ in May 2014. Based on the analysis of environmental variables and water masses,the northeastern South China Sea were divided into three areas: near shore regions,continental shelf regions and deep sea basins. The incubation results showed that phytoplankton did not response significantly to enrichment during incubation in near shore and sea basin stations,whereas increased after 48 h in the area of continental shelf,especially in the group which added both nitrite and phosphate. Trichodesmium were abundant in all experiment stations,while died away quickly during incubation. The phytoplankton species composition and proportion of size fractioned Chl a also changed notably with nutrient enrichment,and the variation was more significant in shelf regions. The results of shelf regions showed that the dominant species shifted from dinoflagellates such as Amphidinium carterae,Dinophysis argus,Prorocentrum sp. to diatoms such as Chaetoceros cinctus,C. curvisetus,C. radicans and Leptocylindrus danicus after incubation. Besides,the results also revealed that phosphate stimulated the growth of picophytoplankton synechococcus in the area of continental shelf significantly.
In situ survey of northeastern South China Sea (20°~24°N,114°~121°E),combined with nutrient (Nitrogen and Phosphorus) enrichment experiments were conducted during a cruise of Shiyan Ⅲ in May 2014. Based on the analysis of environmental variables and water masses,the northeastern South China Sea were divided into three areas: near shore regions,continental shelf regions and deep sea basins. The incubation results showed that phytoplankton did not response significantly to enrichment during incubation in near shore and sea basin stations,whereas increased after 48 h in the area of continental shelf,especially in the group which added both nitrite and phosphate. Trichodesmium were abundant in all experiment stations,while died away quickly during incubation. The phytoplankton species composition and proportion of size fractioned Chl a also changed notably with nutrient enrichment,and the variation was more significant in shelf regions. The results of shelf regions showed that the dominant species shifted from dinoflagellates such as Amphidinium carterae,Dinophysis argus,Prorocentrum sp. to diatoms such as Chaetoceros cinctus,C. curvisetus,C. radicans and Leptocylindrus danicus after incubation. Besides,the results also revealed that phosphate stimulated the growth of picophytoplankton synechococcus in the area of continental shelf significantly.
2015, 37(10): 100-105.
doi: 10.3969/j.issn.0253-4193.2015.10.010
Abstract:
With the increasing application of nanotechnologies,it is no doubt that more and more engineered nanoparticles end up in marine environment. The toxicity of TiO2 particles with different sizes (21 nm,60 nm and 400 nm) to the marine microalga Nitzschia closterium was investigated in this study,including the growth inhibition and oxidative stress. The results showed that the toxicity of 1 mg/L TiO2 particles to N. closterium cells increased with the decrease of particle size,indicating significant nano-effects at 48 h,72 h and 96h exposure,respectively. TiO2 particles induced excessive reactive oxygen species (ROS) which led to oxidative stress on the algal cells. The antioxidant enzyme activities of N. closterium cells could eliminate some ROS in order to protect algae cells. However,the rest could cause oxidative damage and increase malondialdehyde (MDA) levels concomitantly. In addition,the oxidative damage caused by nano-sized TiO2 particles (21nm and 60nm) was greater than micro-sized particles. Superoxide dismutase (SOD) and catalase (CAT) activities of the algal cells had different response under the stress of TiO2 particle with different size. This study shed new light on the assessment of ecological toxicity of engineered nanomaterials.
With the increasing application of nanotechnologies,it is no doubt that more and more engineered nanoparticles end up in marine environment. The toxicity of TiO2 particles with different sizes (21 nm,60 nm and 400 nm) to the marine microalga Nitzschia closterium was investigated in this study,including the growth inhibition and oxidative stress. The results showed that the toxicity of 1 mg/L TiO2 particles to N. closterium cells increased with the decrease of particle size,indicating significant nano-effects at 48 h,72 h and 96h exposure,respectively. TiO2 particles induced excessive reactive oxygen species (ROS) which led to oxidative stress on the algal cells. The antioxidant enzyme activities of N. closterium cells could eliminate some ROS in order to protect algae cells. However,the rest could cause oxidative damage and increase malondialdehyde (MDA) levels concomitantly. In addition,the oxidative damage caused by nano-sized TiO2 particles (21nm and 60nm) was greater than micro-sized particles. Superoxide dismutase (SOD) and catalase (CAT) activities of the algal cells had different response under the stress of TiO2 particle with different size. This study shed new light on the assessment of ecological toxicity of engineered nanomaterials.
2015, 37(10): 106-122.
doi: 10.3969/j.issn.0253-4193.2015.10.011
Abstract:
Multidisciplinary investigations of phytoplankton community in the continental shelf regions of East China Sea (ECS) were performed during four cruises between year 2009-2011 (summer 2009,winter 2009,autumn 2010 and spring 2011). The present study reported the phytoplankton species composition,community structure,its distribution in the ECS in four seasons,and its responses to environmental factors. Phytoplankton in the ECS were mainly composed of diatoms and dinflagellates. A totally,299 taxa (including under defined species) belonging to 88 genera and 5 phyla were identified. The phytoplankton cell abundance was highest in summer,its average was (8 659.572±28 937.27) cell/L,they decreased in turns in autumn,winter and spring. The average of phytoplankton cell abundance was (4 413.726±12 534.573),(218.479±265.897) and (421.773±647.532) cell/L in these three seasons respectively. Diatoms were the major component for the phytoplankton community in three seasons without spring. They took over 96% of the total phytoplankton cell abundance in these three seasons. In spring,dinoflagellates dominanted the whole community occupying 69% of phytoplankton total cell abundance. The high phytoplankton cell abundance appeared near by the Yangtze River Estuary waters,and decreased in offshore reigons. The phytoplankton community displayed species succession and seasonal variations. The species richness was increased in the order of spring,summer,autumn and winter. Shannon-Wiener index and Pielou index shared a similar trend. Margalef index varied with spatio-temporal dimensions. Pearson correlation analysis revealed that phytoplankton community alternating was strongly associated with specific physic-chemical environments.
Multidisciplinary investigations of phytoplankton community in the continental shelf regions of East China Sea (ECS) were performed during four cruises between year 2009-2011 (summer 2009,winter 2009,autumn 2010 and spring 2011). The present study reported the phytoplankton species composition,community structure,its distribution in the ECS in four seasons,and its responses to environmental factors. Phytoplankton in the ECS were mainly composed of diatoms and dinflagellates. A totally,299 taxa (including under defined species) belonging to 88 genera and 5 phyla were identified. The phytoplankton cell abundance was highest in summer,its average was (8 659.572±28 937.27) cell/L,they decreased in turns in autumn,winter and spring. The average of phytoplankton cell abundance was (4 413.726±12 534.573),(218.479±265.897) and (421.773±647.532) cell/L in these three seasons respectively. Diatoms were the major component for the phytoplankton community in three seasons without spring. They took over 96% of the total phytoplankton cell abundance in these three seasons. In spring,dinoflagellates dominanted the whole community occupying 69% of phytoplankton total cell abundance. The high phytoplankton cell abundance appeared near by the Yangtze River Estuary waters,and decreased in offshore reigons. The phytoplankton community displayed species succession and seasonal variations. The species richness was increased in the order of spring,summer,autumn and winter. Shannon-Wiener index and Pielou index shared a similar trend. Margalef index varied with spatio-temporal dimensions. Pearson correlation analysis revealed that phytoplankton community alternating was strongly associated with specific physic-chemical environments.
2015, 37(10): 123-132.
doi: 10.3969/j.issn.0253-4193.2015.10.012
Abstract:
In order to learn the bacterial taxa in unique microhabitat of the surface microalyer,the total numbers of bacteria,culturable bacteria and its community structure were investigated from the surface microlayer and subsurface layer of the northern Yellow Sea. Seawater samples were collected from four sampling times,2010-2011. The total number of bacteria was determined by flow cytometry. The number of culturable bacteria was determined by the plate count method. PCR-16S rDNA and sequencing analysis were used to analyze the features of community structure. The results showed that the average numbers of total bacteria are 1.76×106 CFU/mL in the surface microlayer and 1.07×106 cell/mL in subsurface layer,respectively. The number of culturable bacteria ranged from 1.00×102 CFU/mL to 1.70×106 CFU/mL. The percentage that culturable bacteria occupies in total bacteria were 13.05% and 0.45% in the surface microlayer and subsurface layer,respectively. The enrich factor (EF) of total and cultural bacteria were 2.02 and 74.16 in the surface microlayer. The results showed that the culturable bacteria in this region was attached to four phylogenetic communities: Proteobacteria (94.34%)、Firmicutes (1.89%)、Bacteroidetes (1.89%) and Actinobacteria (1.89%). This research preliminary presented that the surface microlayer in seawater has an high enrichment effect on bacteria,especially for culturable bacteria. The bacterial communities in the surface microlayer and subsurface layer was different,which reflected in wide range of species,diversity of source and function. Therefore,the unique bacterial communities of the surface microlayer is generated towing to its special microhabitat. The ecological function of microorganisms in surface microlayer need to be further understood in the future.
In order to learn the bacterial taxa in unique microhabitat of the surface microalyer,the total numbers of bacteria,culturable bacteria and its community structure were investigated from the surface microlayer and subsurface layer of the northern Yellow Sea. Seawater samples were collected from four sampling times,2010-2011. The total number of bacteria was determined by flow cytometry. The number of culturable bacteria was determined by the plate count method. PCR-16S rDNA and sequencing analysis were used to analyze the features of community structure. The results showed that the average numbers of total bacteria are 1.76×106 CFU/mL in the surface microlayer and 1.07×106 cell/mL in subsurface layer,respectively. The number of culturable bacteria ranged from 1.00×102 CFU/mL to 1.70×106 CFU/mL. The percentage that culturable bacteria occupies in total bacteria were 13.05% and 0.45% in the surface microlayer and subsurface layer,respectively. The enrich factor (EF) of total and cultural bacteria were 2.02 and 74.16 in the surface microlayer. The results showed that the culturable bacteria in this region was attached to four phylogenetic communities: Proteobacteria (94.34%)、Firmicutes (1.89%)、Bacteroidetes (1.89%) and Actinobacteria (1.89%). This research preliminary presented that the surface microlayer in seawater has an high enrichment effect on bacteria,especially for culturable bacteria. The bacterial communities in the surface microlayer and subsurface layer was different,which reflected in wide range of species,diversity of source and function. Therefore,the unique bacterial communities of the surface microlayer is generated towing to its special microhabitat. The ecological function of microorganisms in surface microlayer need to be further understood in the future.
2015, 37(10): 133-140.
doi: 10.3969/j.issn.0253-4193.2015.10.013
Abstract:
Ubiquitin-conjugating enzyme is the second enzyme in the process of protein ubiquitination and plays an important role in ubiquitin transferring and substrate specific recognition. In this study,we cloned the full-length cDNA from the Roughskin sculpin,Trachidermus fasciatus by RACE,and named as TfUbcE2-D2. The cDNA of TfUbcE2-D2 is 993 bp,which contained an open reading frame (ORF) of 444 bp encoding a polypeptide of 147 amino acids. The deduced amino acid sequence had a domain called Ubcc,which was extremely conservative. The mRNA expression of TfUbcE2-D2 in healthy and Vibrio anguillarum challenge was detected by quantitative real-time PCR,results showed that TfUbcE2-D2 was expressed in all the detected tissues,mainly expressed in kidney and gill. The up-regulated of TfUbcE2-D2 post challenge with Vibrio anguillarum in blood,spleen,liver and gill indicated that it might be involved in the innate response of Roughskin sculpin.
Ubiquitin-conjugating enzyme is the second enzyme in the process of protein ubiquitination and plays an important role in ubiquitin transferring and substrate specific recognition. In this study,we cloned the full-length cDNA from the Roughskin sculpin,Trachidermus fasciatus by RACE,and named as TfUbcE2-D2. The cDNA of TfUbcE2-D2 is 993 bp,which contained an open reading frame (ORF) of 444 bp encoding a polypeptide of 147 amino acids. The deduced amino acid sequence had a domain called Ubcc,which was extremely conservative. The mRNA expression of TfUbcE2-D2 in healthy and Vibrio anguillarum challenge was detected by quantitative real-time PCR,results showed that TfUbcE2-D2 was expressed in all the detected tissues,mainly expressed in kidney and gill. The up-regulated of TfUbcE2-D2 post challenge with Vibrio anguillarum in blood,spleen,liver and gill indicated that it might be involved in the innate response of Roughskin sculpin.
2015, 37(10): 141-145.
doi: 10.3969/j.issn.0253-4193.2015.10.014
Abstract:
To compare the capture efficiency for Sagitta crassa(chaetognatha) of three types of plankton nets (505 μm meshed coarse net,200 μm meshed WP-2 net and 77 μm meshed fine net),zooplankton samples were collected in central Bohai Sea in November,2012. The fine net outperformed the other two nets,respectively capturing 1.3 and 2.9 times the abundance of the WP-2 net and the coarse net. The coarse net apparently under-sampled less than 9mm long individuals; the WP-2 net under-sampled less than 4 mm long and a fraction of 4-5 mm long individuals; while the fine net appeared to be slightly less efficient when capturing more than 9 mm long individuals. The capture efficiency was closely correlated to the body size of S. crassa: smaller body size caused greater differences in capture efficiency of the nets. As for more than 9mm long individuals,avoidance of S. crassa probably accounted for the slightly lower capture efficiency of the fine net. We recommend that the fine net be employed for sampling S. crassa during reproduction periods to provide supplementary results to other types of nets,thus more reliable data could be obtained for future research of population dynamics.
To compare the capture efficiency for Sagitta crassa(chaetognatha) of three types of plankton nets (505 μm meshed coarse net,200 μm meshed WP-2 net and 77 μm meshed fine net),zooplankton samples were collected in central Bohai Sea in November,2012. The fine net outperformed the other two nets,respectively capturing 1.3 and 2.9 times the abundance of the WP-2 net and the coarse net. The coarse net apparently under-sampled less than 9mm long individuals; the WP-2 net under-sampled less than 4 mm long and a fraction of 4-5 mm long individuals; while the fine net appeared to be slightly less efficient when capturing more than 9 mm long individuals. The capture efficiency was closely correlated to the body size of S. crassa: smaller body size caused greater differences in capture efficiency of the nets. As for more than 9mm long individuals,avoidance of S. crassa probably accounted for the slightly lower capture efficiency of the fine net. We recommend that the fine net be employed for sampling S. crassa during reproduction periods to provide supplementary results to other types of nets,thus more reliable data could be obtained for future research of population dynamics.
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