2018 Vol. 40, No. 1
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2018, 40(1): .
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2018, 40(1): .
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2018, 40(1): 1-9.
doi: 10.3969/j.issn.0253-4193.2018.01.001
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In this paper, the research advances in the impacts of Langmuir Circulation (LC) on ocean mixing under the typhoon condition in the past 10 years is reviewed. It has been widely recognized that Langmuir turbulence plays an important role in the forming and deepening of the upper mixed layer. But the mechanism and degree of the LC effects on the upper ocean mixing still have many uncertainties. Observations indicated that, under the action of typhoon, the average vertical kinetic energy of the mixed layer near the eye was strongly depressed, which may be related to the variation of the Langmuir induced turbulence at different locations of typhoon. Under typhoon condition, the existing Langmuir parameterization schemes have appreciable deviations when simulating the upper ocean mixing. Thus, in future studies, an improved approximation of the Stokes drift velocity profile and the explicitly resolving the sea-state-dependent Langmuir turbulence will lead to increased accuracy in predicting the ocean response in coupled tropical cyclone-ocean models,that is a necessary way to reveal the mechanism of the LC effects on the upper ocean mixing under typhoon condition.
In this paper, the research advances in the impacts of Langmuir Circulation (LC) on ocean mixing under the typhoon condition in the past 10 years is reviewed. It has been widely recognized that Langmuir turbulence plays an important role in the forming and deepening of the upper mixed layer. But the mechanism and degree of the LC effects on the upper ocean mixing still have many uncertainties. Observations indicated that, under the action of typhoon, the average vertical kinetic energy of the mixed layer near the eye was strongly depressed, which may be related to the variation of the Langmuir induced turbulence at different locations of typhoon. Under typhoon condition, the existing Langmuir parameterization schemes have appreciable deviations when simulating the upper ocean mixing. Thus, in future studies, an improved approximation of the Stokes drift velocity profile and the explicitly resolving the sea-state-dependent Langmuir turbulence will lead to increased accuracy in predicting the ocean response in coupled tropical cyclone-ocean models,that is a necessary way to reveal the mechanism of the LC effects on the upper ocean mixing under typhoon condition.
2018, 40(1): 10-16.
doi: 10.3969/j.issn.0253-4193.2018.01.002
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Based on the Massachusetts Institute of Technology General Circulation Model, the numerical simulation of the internal tide in the northern South China Sea (SCS) is carried out by using the actual bathymetry, stratification and tidal current force. The differences of the internal tide in the northern South China Sea during the two seasons are analyzed. The results show that the velocity in the K1 and M2 is 10.1% and 44.7% stronger than that in the summer. The results of the vertical modal analysis show that although the tidal kinetic energy density in the first modal is 15.5% lower in winter than that in summer, the second and third modal tides are about 25.1% and 33.2% higher. These high-mode tides may lead to intense vertical shear in the deep basin of SCS in winter, indicating that the stronger high-mode tide may be one of the reasons for the intense mixing of the deep SCS in winter.
Based on the Massachusetts Institute of Technology General Circulation Model, the numerical simulation of the internal tide in the northern South China Sea (SCS) is carried out by using the actual bathymetry, stratification and tidal current force. The differences of the internal tide in the northern South China Sea during the two seasons are analyzed. The results show that the velocity in the K1 and M2 is 10.1% and 44.7% stronger than that in the summer. The results of the vertical modal analysis show that although the tidal kinetic energy density in the first modal is 15.5% lower in winter than that in summer, the second and third modal tides are about 25.1% and 33.2% higher. These high-mode tides may lead to intense vertical shear in the deep basin of SCS in winter, indicating that the stronger high-mode tide may be one of the reasons for the intense mixing of the deep SCS in winter.
2018, 40(1): 17-28.
doi: 10.3969/j.issn.0253-4193.2018.01.003
Abstract:
The monthly sea surface temperature (SST) data of 27 marine observation stations have been detected and adjusted by the Penalized Maximal T test (PMT) and the detailed metadata archive. In this study, the homogenous surface air temperature (SAT) data from neighboring meteorological observation stations are used to construct the reference series by correlation coefficient weighted averaged method. Results show that almost all of the stations along coast of the China Seas, the inhomogenities or change points can be detected. Combined with the detailed metadata of each station, the main reasons causing the inhomogenization problems are instrument change (including the change from artificial observation to automations) and relocation, accounting for about 52.4% and 33.3% of the total change points. It is also found that the annual mean SST trend has changed obviously and homogeneity is improved well after adjustment. The warming rate of SST series along the coast of the China Seas after adjustment is much larger than that before adjustment. This phenomenon links tightly to the SST decreasing after automation which leads to the large proportion of negative correction values.
The monthly sea surface temperature (SST) data of 27 marine observation stations have been detected and adjusted by the Penalized Maximal T test (PMT) and the detailed metadata archive. In this study, the homogenous surface air temperature (SAT) data from neighboring meteorological observation stations are used to construct the reference series by correlation coefficient weighted averaged method. Results show that almost all of the stations along coast of the China Seas, the inhomogenities or change points can be detected. Combined with the detailed metadata of each station, the main reasons causing the inhomogenization problems are instrument change (including the change from artificial observation to automations) and relocation, accounting for about 52.4% and 33.3% of the total change points. It is also found that the annual mean SST trend has changed obviously and homogeneity is improved well after adjustment. The warming rate of SST series along the coast of the China Seas after adjustment is much larger than that before adjustment. This phenomenon links tightly to the SST decreasing after automation which leads to the large proportion of negative correction values.
2018, 40(1): 29-38.
doi: 10.3969/j.issn.0253-4193.2018.01.004
Abstract:
The geostationary optical satellite GF-4 has the unique advantages of high temporal resolution (20s) and high spatial resolution (50m). In order to explore GF-4's potential in ocean disaster monitoring, the maximum cross correlation method (MCC) was applied to four GF-4 satellite images on June 25th, 2016 to extract the drifting velocity of the green tide in the Yellow Sea, and the influences of wind and tide on the green tide movement were analyzed. (1) The MCC method is shown to be capable of automatically tracking the green tide patches movement on the minute scale (8-9 min) in the GF-4 images with a high accuracy, with the absolute percentage difference (APD) of velocity magnitude and direction of 11% and 5%, respectively. When the temporal interval between the two GF-4 images increased to several hours (e.g., 6 h), the accuracy of MCC tracking decreased due to the obvious shape changes of green tide patch. (2) The drifting velocity of the green tide during the daytime can change significantly. At 9:00 am, the green tide patches had an average velocity of (0.36±0.13) m/s and moved southeast. But at 3:00 pm, the velocity increased to (0.69±0.12) m/s and the patches moved toward northwest direction. (3) The drifting velocity of green tide had a close correlation with wind speed (r=0.74); and green tide patches' movement direction was also in good accordance with local tide cycle. The GF-4 data can provide data support for accurate monitoring of green tide short-term movement.
The geostationary optical satellite GF-4 has the unique advantages of high temporal resolution (20s) and high spatial resolution (50m). In order to explore GF-4's potential in ocean disaster monitoring, the maximum cross correlation method (MCC) was applied to four GF-4 satellite images on June 25th, 2016 to extract the drifting velocity of the green tide in the Yellow Sea, and the influences of wind and tide on the green tide movement were analyzed. (1) The MCC method is shown to be capable of automatically tracking the green tide patches movement on the minute scale (8-9 min) in the GF-4 images with a high accuracy, with the absolute percentage difference (APD) of velocity magnitude and direction of 11% and 5%, respectively. When the temporal interval between the two GF-4 images increased to several hours (e.g., 6 h), the accuracy of MCC tracking decreased due to the obvious shape changes of green tide patch. (2) The drifting velocity of the green tide during the daytime can change significantly. At 9:00 am, the green tide patches had an average velocity of (0.36±0.13) m/s and moved southeast. But at 3:00 pm, the velocity increased to (0.69±0.12) m/s and the patches moved toward northwest direction. (3) The drifting velocity of green tide had a close correlation with wind speed (r=0.74); and green tide patches' movement direction was also in good accordance with local tide cycle. The GF-4 data can provide data support for accurate monitoring of green tide short-term movement.
2018, 40(1): 39-46.
doi: 10.3969/j.issn.0253-4193.2018.01.005
Abstract:
Environmental uncertainty often represents the limiting factor in matched-field localization. Within a Bayesian framework, environmental focalization has been widely applied to solve the augmented localization problem, in which the environmental parameters, source ranges and depths are considered to be unknown variables. However, including environmental parameters in multiple-source localization greatly increases the complexity and computational demands of the inverse problem. It has to estimate lots of unknown parameters by limited observation information. In the approach, the closed-form maximum-likelihood expressions for source strengths and noise variance at each frequency allow these parameters to be sampled implicitly, substantially reducing the dimensionality and difficulty of the inversion. Genetic algorithms are used for the optimization and all the samples of the parameter space are used to estimate the a posteriori probabilities of the model parameters. In order to compensate for the precocious disadvantage of genetic algorithm, the likelihood function is expressed as the empirical exponent relation of the cost function. This method integrates the a posterior probability density over environmental parameters to obtain a sequence of marginal probability distributions over source range and depth, from which the most-probable source location and localization uncertainties can be extracted. Examples are presented for multi-frequency localization of two sources in an uncertain shallow water environment, and a Monte Carlo performance evaluation study is carried out.
Environmental uncertainty often represents the limiting factor in matched-field localization. Within a Bayesian framework, environmental focalization has been widely applied to solve the augmented localization problem, in which the environmental parameters, source ranges and depths are considered to be unknown variables. However, including environmental parameters in multiple-source localization greatly increases the complexity and computational demands of the inverse problem. It has to estimate lots of unknown parameters by limited observation information. In the approach, the closed-form maximum-likelihood expressions for source strengths and noise variance at each frequency allow these parameters to be sampled implicitly, substantially reducing the dimensionality and difficulty of the inversion. Genetic algorithms are used for the optimization and all the samples of the parameter space are used to estimate the a posteriori probabilities of the model parameters. In order to compensate for the precocious disadvantage of genetic algorithm, the likelihood function is expressed as the empirical exponent relation of the cost function. This method integrates the a posterior probability density over environmental parameters to obtain a sequence of marginal probability distributions over source range and depth, from which the most-probable source location and localization uncertainties can be extracted. Examples are presented for multi-frequency localization of two sources in an uncertain shallow water environment, and a Monte Carlo performance evaluation study is carried out.
2018, 40(1): 47-56.
doi: 10.3969/j.issn.0253-4193.2018.01.006
Abstract:
In this study, we assessed the burial fluxes and source appointment of different forms of carbon in core sediments collected from culture areas in Sanggou Bay, and preliminarily analyzed the otherness in different position. Water circulation and the propagation and wreckage of shellfish and algae in Sanggou Bay dominated the carbon burial. The average content of total carbon (TC),organic carbon (TOC) and inorganic carbon (TIC) in Sanggou Bay were 1.79%,0.54% and1.25%. TOC accounted for a small proportion in TC, mostly of which derived from terrigenous organic carbon (Ct), and while the proportion of marine-derived organic carbon (Ca) increased significantly since the beginning of large-scale aquaculture. The average TC burial fluxes was 228.9 g/(m2·a), which was dominated by TIC (about 70%). High sedimentation rate and biological wreckage settlement distinguished the source and burial fluxes of carbon in Sanggou Bay from other coastal areas.
In this study, we assessed the burial fluxes and source appointment of different forms of carbon in core sediments collected from culture areas in Sanggou Bay, and preliminarily analyzed the otherness in different position. Water circulation and the propagation and wreckage of shellfish and algae in Sanggou Bay dominated the carbon burial. The average content of total carbon (TC),organic carbon (TOC) and inorganic carbon (TIC) in Sanggou Bay were 1.79%,0.54% and1.25%. TOC accounted for a small proportion in TC, mostly of which derived from terrigenous organic carbon (Ct), and while the proportion of marine-derived organic carbon (Ca) increased significantly since the beginning of large-scale aquaculture. The average TC burial fluxes was 228.9 g/(m2·a), which was dominated by TIC (about 70%). High sedimentation rate and biological wreckage settlement distinguished the source and burial fluxes of carbon in Sanggou Bay from other coastal areas.
2018, 40(1): 57-67.
doi: 10.3969/j.issn.0253-4193.2018.01.007
Abstract:
Using the marine self-potential method could explore the position and size of the seafloor hydrothermal polymetallic sulfide ore body. In the practical marine investigation, we could use the horizontal and vertical measurements. Here we used the numerical simulation method to analyze the detection effection of these two measuring ways. The analysis result indicates that vertical measurements could get a bigger anomaly than horizontal measurements. And the lateral resolution of vertical measurements is higher than horizontal. While vertical observation system's electrode is more close to the seafloor and have bigger operating risk than horizontal measurements. We need choose applicable detection system and observation way according to actual requirements. In the actual detection, there will be an angle between the electrodes and the horizontal direction. It will lead to a change of anomalies. We need to notice it in the data processing and interpretation. It can provide us with some reference about the marine exploration of the seafloor polymetallic sulfide.
Using the marine self-potential method could explore the position and size of the seafloor hydrothermal polymetallic sulfide ore body. In the practical marine investigation, we could use the horizontal and vertical measurements. Here we used the numerical simulation method to analyze the detection effection of these two measuring ways. The analysis result indicates that vertical measurements could get a bigger anomaly than horizontal measurements. And the lateral resolution of vertical measurements is higher than horizontal. While vertical observation system's electrode is more close to the seafloor and have bigger operating risk than horizontal measurements. We need choose applicable detection system and observation way according to actual requirements. In the actual detection, there will be an angle between the electrodes and the horizontal direction. It will lead to a change of anomalies. We need to notice it in the data processing and interpretation. It can provide us with some reference about the marine exploration of the seafloor polymetallic sulfide.
2018, 40(1): 68-76.
doi: 10.3969/j.issn.0253-4193.2018.01.008
Abstract:
Observation shows that the effect of the internal solitary waves (ISWs) along the slope on the seabed sediments is like a water cleaner, which is the strongest in the crushing phase and even triggers a series of geological activities and disasters. In order to define the dynamic capability and influencing factors of the ISWs in the process, continuous interaction between the different amplitudes solitons and the different types of sediments was simulated in the large gravity stratified flow tank. The changes of pore water pressure in the process were recorded by the pore water pressure acquisition system. The pore pressure in sediments were compared and analyzed under different hydrodynamic, slope and sedimentary types. The results show that there are similar "U" negative excess pore water pressure changes in the process of wave breaking in different wave broken points. The location waves passing through shows a pore pressure response and it is positively correlated with the surface wave pressure. The amplitude of the excess pore water pressure with depth at the solitary wave broken point, which is reduced to about 50% at about 6% of the wavelength. The amplitude of pore pressure is related to sediment type and wave amplitude. When the slope changes from 0.071 to 0.160, the wave pressure amplitude can be increased to 1.6 times. The change of the amplitude of the solitary wave is only related to the excess pore water pressure value, which does not affect the dynamic response of the seabed.
Observation shows that the effect of the internal solitary waves (ISWs) along the slope on the seabed sediments is like a water cleaner, which is the strongest in the crushing phase and even triggers a series of geological activities and disasters. In order to define the dynamic capability and influencing factors of the ISWs in the process, continuous interaction between the different amplitudes solitons and the different types of sediments was simulated in the large gravity stratified flow tank. The changes of pore water pressure in the process were recorded by the pore water pressure acquisition system. The pore pressure in sediments were compared and analyzed under different hydrodynamic, slope and sedimentary types. The results show that there are similar "U" negative excess pore water pressure changes in the process of wave breaking in different wave broken points. The location waves passing through shows a pore pressure response and it is positively correlated with the surface wave pressure. The amplitude of the excess pore water pressure with depth at the solitary wave broken point, which is reduced to about 50% at about 6% of the wavelength. The amplitude of pore pressure is related to sediment type and wave amplitude. When the slope changes from 0.071 to 0.160, the wave pressure amplitude can be increased to 1.6 times. The change of the amplitude of the solitary wave is only related to the excess pore water pressure value, which does not affect the dynamic response of the seabed.
2018, 40(1): 77-86.
doi: 10.3969/j.issn.0253-4193.2018.01.009
Abstract:
Anchoveta (Engraulis ringens) is a small pelagic fish living in the coastal area at the Southeast Pacific Ocean. Forecasting anchoveta biomass effectively could provide decision supports for China's fishmeal import enterprises. Therefore, in this study, combining the biological factors (percentage of juvenile and previous biomass), oceanic environmental factors (temperature status in the fishing ground and climatic variations) and catch, we built the anchoveta biomass forecasting model in the seventeen fishing season (from 2006 to the first fishing season of 2014) combining the methods of principal component analysis (PCA) and multiple linear regression. Besides, we evaluated the factors affecting the changes of anchoveta biomass by the result of PCA. With the increase of sample size, the mean of relative error to the predicting sequences and actual sequences became smaller, and the correlation coefficient decreased. Finally, model 5 (modeling the data from 2006 to 2013 and validating the data in the first fishing season of 2014) could effectively fit out the changing trends of avchoveta biomass:the correlation coefficient of predicting sequences and actual sequences was 0.86 and the mean of relative error for these two sequences was 12%. What's more, the relative error was only 1% for the predicting value in the first fishing season at 2014. The results of correlation coefficients between the anchoveta biomass sequence and the scores of principal components sequence indicated that environmental factor could have huge impacts to the anchoveta biomass variations.
Anchoveta (Engraulis ringens) is a small pelagic fish living in the coastal area at the Southeast Pacific Ocean. Forecasting anchoveta biomass effectively could provide decision supports for China's fishmeal import enterprises. Therefore, in this study, combining the biological factors (percentage of juvenile and previous biomass), oceanic environmental factors (temperature status in the fishing ground and climatic variations) and catch, we built the anchoveta biomass forecasting model in the seventeen fishing season (from 2006 to the first fishing season of 2014) combining the methods of principal component analysis (PCA) and multiple linear regression. Besides, we evaluated the factors affecting the changes of anchoveta biomass by the result of PCA. With the increase of sample size, the mean of relative error to the predicting sequences and actual sequences became smaller, and the correlation coefficient decreased. Finally, model 5 (modeling the data from 2006 to 2013 and validating the data in the first fishing season of 2014) could effectively fit out the changing trends of avchoveta biomass:the correlation coefficient of predicting sequences and actual sequences was 0.86 and the mean of relative error for these two sequences was 12%. What's more, the relative error was only 1% for the predicting value in the first fishing season at 2014. The results of correlation coefficients between the anchoveta biomass sequence and the scores of principal components sequence indicated that environmental factor could have huge impacts to the anchoveta biomass variations.
2018, 40(1): 87-95.
doi: 10.3969/j.issn.0253-4193.2018.01.010
Abstract:
Chub mackerel (Scomber japonicus) is an important economic fish species in China's coastal waters and its internannual resources has a great fluctuation, which is influenced by physical environment. In the paper, an individual-based model of early life-history stages was used to simulate the mount of Chub mackerel's recruitment in the East China Sea during 1978-2013. The result showed that the changes in the physical environment did lead to an interannual fluctuation of Chub mackerel's recruitment in the East China Sea and there was a large fluctuation in late 90s, with the largest amount of recruitment resources in 2002 (1.8×109 ind) and the least one in 1996 (6.5×108 ind), the amount of difference recruitment between 2002 and 1996 is 1.15×109 ind. 15-30 days after spawning, that was the ocean physical environment in April played an important role in recruitment of Chub mackerel in the East China Sea and the survival amount of eggs and larvae in late April basically determined the amount of final Chub mackerel's recruitment. The water temperature was one important physical factors affecting recruitment of Chub mackerel. The higher water temperature was beneficial to improve recruitment of Chub mackerel, On the contrary, the lower one was not conducive to recruitment of the Chub mackerel. Taiwan Warm Current (TWC) was another important physical factor affecting the recruitment of Chub mackerel. The bigger velocity of TWC in April was beneficial to the recruitment. On the contrary, the smaller one was unfavorable to the recruitment. So the water temperature and velocity of TWC in April did determine the final amount of Chub mackerel's recruitment in the East China Sea.
Chub mackerel (Scomber japonicus) is an important economic fish species in China's coastal waters and its internannual resources has a great fluctuation, which is influenced by physical environment. In the paper, an individual-based model of early life-history stages was used to simulate the mount of Chub mackerel's recruitment in the East China Sea during 1978-2013. The result showed that the changes in the physical environment did lead to an interannual fluctuation of Chub mackerel's recruitment in the East China Sea and there was a large fluctuation in late 90s, with the largest amount of recruitment resources in 2002 (1.8×109 ind) and the least one in 1996 (6.5×108 ind), the amount of difference recruitment between 2002 and 1996 is 1.15×109 ind. 15-30 days after spawning, that was the ocean physical environment in April played an important role in recruitment of Chub mackerel in the East China Sea and the survival amount of eggs and larvae in late April basically determined the amount of final Chub mackerel's recruitment. The water temperature was one important physical factors affecting recruitment of Chub mackerel. The higher water temperature was beneficial to improve recruitment of Chub mackerel, On the contrary, the lower one was not conducive to recruitment of the Chub mackerel. Taiwan Warm Current (TWC) was another important physical factor affecting the recruitment of Chub mackerel. The bigger velocity of TWC in April was beneficial to the recruitment. On the contrary, the smaller one was unfavorable to the recruitment. So the water temperature and velocity of TWC in April did determine the final amount of Chub mackerel's recruitment in the East China Sea.
2018, 40(1): 96-105.
doi: 10.3969/j.issn.0253-4193.2018.01.011
Abstract:
Based on the fishery resources survey data of Xiao Yangshan adjacent waters in the autumn of 2014 and 2015, the ecological relationship between the major nekton were analyzed via niche breadth, niche overlap, cluster analysis,W-test, χ2-test, association coefficient (AC) and percentage of co-occurrence (PC). The results showed that there were 24 major nekton species in this area. The dominant species were Harpodon nehereus, Portunus trituberculatus and Exopalaemon annandalei. Among the totally 24 major nekton species, the values of niche breadth of these 3 species larger than other species. The major nekton species can be divided into three groups based on the niche breadth cluster analysis, they were wide niche breadth species, moderate niche breadth and narrow niche breadth species. The values of niche overlap between species varied from 0 to 0.96, which showed that the ability of species to using resources have similarity and there was a certain degree of competition between species. The W-test showed that there were significant positive correlation among the major nekton species. The χ2-test suggested that there were significantly interspecific association for 150 species pairs (χ2 ≥ 3.841). The results of AC and PC revealed that the association of interspecific was strong and the overall tend to be positive correlation.
Based on the fishery resources survey data of Xiao Yangshan adjacent waters in the autumn of 2014 and 2015, the ecological relationship between the major nekton were analyzed via niche breadth, niche overlap, cluster analysis,W-test, χ2-test, association coefficient (AC) and percentage of co-occurrence (PC). The results showed that there were 24 major nekton species in this area. The dominant species were Harpodon nehereus, Portunus trituberculatus and Exopalaemon annandalei. Among the totally 24 major nekton species, the values of niche breadth of these 3 species larger than other species. The major nekton species can be divided into three groups based on the niche breadth cluster analysis, they were wide niche breadth species, moderate niche breadth and narrow niche breadth species. The values of niche overlap between species varied from 0 to 0.96, which showed that the ability of species to using resources have similarity and there was a certain degree of competition between species. The W-test showed that there were significant positive correlation among the major nekton species. The χ2-test suggested that there were significantly interspecific association for 150 species pairs (χ2 ≥ 3.841). The results of AC and PC revealed that the association of interspecific was strong and the overall tend to be positive correlation.
2018, 40(1): 106-114.
doi: 10.3969/j.issn.0253-4193.2018.01.012
Abstract:
We studied the effects of Cu2+ on the peroxidase activity and structure ofthe Tegillarca granosa hemoglobin (Tg-HbⅡ),and the protective action of Pro to the Tg-HbⅡthat has been treated by Cu2+. The results showed that the peroxidase activity of Tg-HbⅡ was gradually decreased with the increase of Cu2+ concentration, and the inhibition of Cu2+ to Tg-HbⅡperoxidase activity belonged to noncompetitive-competitive mixed inhibition type.The inactivation rate was in a concentration-dependent manner, and the inactivation process showed a single-phase change, which showed a first-order reaction kinetics. The results also indicated that different concentrations of Cu2+ could affect the tertiary structure of Tg-HbⅡ. In addition, Pro could protect the spatial structure of Tg-HbⅡ and restore its peroxidase activity destroyed by Cu2+, which successfully blocked Tg-HbⅡaggregation, recoverying the conformation and activity of Tg-HbⅡ.
We studied the effects of Cu2+ on the peroxidase activity and structure ofthe Tegillarca granosa hemoglobin (Tg-HbⅡ),and the protective action of Pro to the Tg-HbⅡthat has been treated by Cu2+. The results showed that the peroxidase activity of Tg-HbⅡ was gradually decreased with the increase of Cu2+ concentration, and the inhibition of Cu2+ to Tg-HbⅡperoxidase activity belonged to noncompetitive-competitive mixed inhibition type.The inactivation rate was in a concentration-dependent manner, and the inactivation process showed a single-phase change, which showed a first-order reaction kinetics. The results also indicated that different concentrations of Cu2+ could affect the tertiary structure of Tg-HbⅡ. In addition, Pro could protect the spatial structure of Tg-HbⅡ and restore its peroxidase activity destroyed by Cu2+, which successfully blocked Tg-HbⅡaggregation, recoverying the conformation and activity of Tg-HbⅡ.
2018, 40(1): 115-128.
doi: 10.3969/j.issn.0253-4193.2018.01.013
Abstract:
Based on the net-phytoplankton data collected from Bohai Bay ecological monitoring area in the summer of 2004-2015, interannual variability in phytoplankton community and 96 species were studied. Results showed, a total of 5 phyla including 120 species of phytoplankton were identified in recent 12 years, in which diatoms and dinoflagellates are the most dominant groups and 59% are red-tide species. The species numbers of all the years varied from 23 to 61, and annual cell abundances from 7×104 cells/m3 to 87 731×104 cells/m3. The biodiversity indexes ranged from 1.13 to 3.04, richness indexes 0.36-1.12 and evenness indexes 0.31-0.72. During 12 years, the species numbers and cell abundances have displayed an increasing trend, while the biodiversity and richness increased with fluctuation, the evenness index showed a slight trend of declination. Around 10 species were identified every year, and 23 species were only observed once. For the occurrence rate, only 4 species occurred in more than 50% stations, and 57 species less than 0.01% stations. Coscinodiscus asteromphalus, Skeletonema costatum, Coscinodiscus granii, Ceratium furca and Chaetoceros curvisetus were dominant species. The cell abundances in recent 5 years were much higher than those before 2010. Specifically, 10 common species showed a blooming trend such as Coscinodiscus granii, Skeletonema costatum and Noctiluca scintillans. While sub-common species such as Nitzschia longissima, Coscinodiscus asteromphalus and Chaetoceros borealis decreased gradually. This study would be of great significance to understand current phytoplankton status and variation trends.
Based on the net-phytoplankton data collected from Bohai Bay ecological monitoring area in the summer of 2004-2015, interannual variability in phytoplankton community and 96 species were studied. Results showed, a total of 5 phyla including 120 species of phytoplankton were identified in recent 12 years, in which diatoms and dinoflagellates are the most dominant groups and 59% are red-tide species. The species numbers of all the years varied from 23 to 61, and annual cell abundances from 7×104 cells/m3 to 87 731×104 cells/m3. The biodiversity indexes ranged from 1.13 to 3.04, richness indexes 0.36-1.12 and evenness indexes 0.31-0.72. During 12 years, the species numbers and cell abundances have displayed an increasing trend, while the biodiversity and richness increased with fluctuation, the evenness index showed a slight trend of declination. Around 10 species were identified every year, and 23 species were only observed once. For the occurrence rate, only 4 species occurred in more than 50% stations, and 57 species less than 0.01% stations. Coscinodiscus asteromphalus, Skeletonema costatum, Coscinodiscus granii, Ceratium furca and Chaetoceros curvisetus were dominant species. The cell abundances in recent 5 years were much higher than those before 2010. Specifically, 10 common species showed a blooming trend such as Coscinodiscus granii, Skeletonema costatum and Noctiluca scintillans. While sub-common species such as Nitzschia longissima, Coscinodiscus asteromphalus and Chaetoceros borealis decreased gradually. This study would be of great significance to understand current phytoplankton status and variation trends.
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