2019 Vol. 41, No. 6
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2019, 41(6): .
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2019, 41(6): 1-11.
doi: 10.3969/j.issn.0253-4193.2019.06.001
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To research the response of the sea surface to the tropical cyclone (TC) wind stress, the paper researches the ocean linear reduced gravity equations. Here are the conclusions:It's more convenient to use the polar coordinates which move with the typhoon when research the ocean response to the TC wind stress. The TC wind stress is static inside the typhoon cloud wall, decrease with the increase of the radius of the polar coordinates in an inverse proportion outside the cyclone cloud wall. In the polar coordinates, the response has a constant analytical special solution. The strength has a proportional relation with the wind stress. The constant special solution is static inside the cloud wall. It presents a form of a cyclone out the cloud wall. The solution decreases when radius of the polar coordinates increases. At the position which is not far out of the cloud wall, the tangential current is larger than the radial current. The radial current is larger than the tangential current away from the cloud wall. The radial current is balance with the tangential wind stress of TC. The tangential current is a gradient current. The current is horizontal no divergence. Inside the eye of TC and the cloud wall, the thickness of the upper ocean reaches its minimum. Its value won't change. The value increases out the cloud wall. The change of the thickness reflects the change of a pycnocline. At the minimum or small position of the value, the pycnocline evidently increases, which will cause the upwelling of the seawater near the pycnocline. The response cyclone is cold. Ignore the response of the surface to the movement of the tropical cyclone, and move the solution in the polar coordinate to a stable coordinate, the spatial distribution of the solution won't change. The constant special solution changes to an inconstant solution, and moves the tropical cyclone. The most important physical property of the solution is quasi-balanced, which essentially distinguishes from near inertial oscillations and gravitational internal waves.
To research the response of the sea surface to the tropical cyclone (TC) wind stress, the paper researches the ocean linear reduced gravity equations. Here are the conclusions:It's more convenient to use the polar coordinates which move with the typhoon when research the ocean response to the TC wind stress. The TC wind stress is static inside the typhoon cloud wall, decrease with the increase of the radius of the polar coordinates in an inverse proportion outside the cyclone cloud wall. In the polar coordinates, the response has a constant analytical special solution. The strength has a proportional relation with the wind stress. The constant special solution is static inside the cloud wall. It presents a form of a cyclone out the cloud wall. The solution decreases when radius of the polar coordinates increases. At the position which is not far out of the cloud wall, the tangential current is larger than the radial current. The radial current is larger than the tangential current away from the cloud wall. The radial current is balance with the tangential wind stress of TC. The tangential current is a gradient current. The current is horizontal no divergence. Inside the eye of TC and the cloud wall, the thickness of the upper ocean reaches its minimum. Its value won't change. The value increases out the cloud wall. The change of the thickness reflects the change of a pycnocline. At the minimum or small position of the value, the pycnocline evidently increases, which will cause the upwelling of the seawater near the pycnocline. The response cyclone is cold. Ignore the response of the surface to the movement of the tropical cyclone, and move the solution in the polar coordinate to a stable coordinate, the spatial distribution of the solution won't change. The constant special solution changes to an inconstant solution, and moves the tropical cyclone. The most important physical property of the solution is quasi-balanced, which essentially distinguishes from near inertial oscillations and gravitational internal waves.
2019, 41(6): 12-22.
doi: 10.3969/j.issn.0253-4193.2019.06.002
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The Chenhang Reservoir, Qingcaosha Reservoir and Dongfengxisha Reservoir have been built in the Changjiang River Estuary, which supply about 80% freshwater for Shanghai. With social and economic development, there is still insufficiency of water supply in Shanghai. The lower Biandan Shoal is located at the upstream of bifurcation between the North Chanel and South Chanel, which reveals wet sand during ebb in spring tide. We applied the 3 dimension numerical model of saltwater intrusion in the Changjiang River Estuary which is developed and applied by the authors' research group for long term, and calculated the longest continuous not suitable take water times in the case of the extremely low river discharge in 1978-1979 to know whether the lower Biandan Shoal can be as a reserve water resource. The model was validated with the observed data at the 8 sites in the North Branch from February 19 to March 1, 2017. The results show that the mean correlation coefficients, root-mean-square error and skill scores for comparison of modelled and observed surface and bottom salinity are 0.85, 1.82 and 0.82, respectively, indicating that the calculated salinity agrees well with the observed data, and the model can preferably simulate the saltwater intrusion in the Changjiang River Estuary. The model calculation shows that the longest continuous not suitable take water times at the model output site in the lower Biandan Shoal is 13.79 d, the source of saltwater intrusion is mainly from the upstream saltwater spilling over from the North Branch into the South Branch during the later spring tide and middle tide after spring tide, and the downstream saltwater intruding directly from the sea during the middle tide after neap tide, and the former influence is greater than the latter one. The duration in which the freshwater can be taken just occurs during the middle tide after neap tide, which is advected by ebb current along the southern side of the South Branch. The longest continuous not suitable take water times at the lower Biandan Shoal is greatly shorter than the ones at the Qingcaosha Reservoir and Dongfengxisha Reservoir, meaning that the freshwater resource at the lower Biandan Shoal is more sufficient than the ones at the upstream and downstream of the South Branch, and is an excellent reserve water resource.
The Chenhang Reservoir, Qingcaosha Reservoir and Dongfengxisha Reservoir have been built in the Changjiang River Estuary, which supply about 80% freshwater for Shanghai. With social and economic development, there is still insufficiency of water supply in Shanghai. The lower Biandan Shoal is located at the upstream of bifurcation between the North Chanel and South Chanel, which reveals wet sand during ebb in spring tide. We applied the 3 dimension numerical model of saltwater intrusion in the Changjiang River Estuary which is developed and applied by the authors' research group for long term, and calculated the longest continuous not suitable take water times in the case of the extremely low river discharge in 1978-1979 to know whether the lower Biandan Shoal can be as a reserve water resource. The model was validated with the observed data at the 8 sites in the North Branch from February 19 to March 1, 2017. The results show that the mean correlation coefficients, root-mean-square error and skill scores for comparison of modelled and observed surface and bottom salinity are 0.85, 1.82 and 0.82, respectively, indicating that the calculated salinity agrees well with the observed data, and the model can preferably simulate the saltwater intrusion in the Changjiang River Estuary. The model calculation shows that the longest continuous not suitable take water times at the model output site in the lower Biandan Shoal is 13.79 d, the source of saltwater intrusion is mainly from the upstream saltwater spilling over from the North Branch into the South Branch during the later spring tide and middle tide after spring tide, and the downstream saltwater intruding directly from the sea during the middle tide after neap tide, and the former influence is greater than the latter one. The duration in which the freshwater can be taken just occurs during the middle tide after neap tide, which is advected by ebb current along the southern side of the South Branch. The longest continuous not suitable take water times at the lower Biandan Shoal is greatly shorter than the ones at the Qingcaosha Reservoir and Dongfengxisha Reservoir, meaning that the freshwater resource at the lower Biandan Shoal is more sufficient than the ones at the upstream and downstream of the South Branch, and is an excellent reserve water resource.
2019, 41(6): 23-36.
doi: 10.3969/j.issn.0253-4193.2019.06.003
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The Qinhuangdao coastal area is a significant passage through which the substance and energy are exchanged among the Liaodong Bay, the central of Bohai Sea and the Bohai Bay. In this paper, based on the in-situ current data obtained from seabed-based platform continuously in the Qinhuangdao coastal area in summer and autumn, we study the characteristics of current and its response to large-scale mariculture by means of harmonic analysis and filtering. The results are shown as follows:the most prominent semi-diurnal tidal current is the M2 tidal component with the maximum tidal velocity ranging from 20.0 cm/s to 36.9 cm/s, which is much smaller than the maximum velocity of M2 tidal current in the east side of Liaodong Bay. In autumn, the velocities of the residual currents in the Qinhuangdao coastal area, which are between 0.2 cm/s and 2.5 cm/s, are weaker than those in the east side of Liaodong Bay. Meanwhile, there may exist a weak clockwise circulation in the bottom of the Liaodong Bay. In summer,the maximum velocities of M2 and K1 tidal current components are larger than those in autumn. Aquaculture activities have a greater impact on the residual currents. Compared with the vertically-averaged residual current in site A6 which located at the edge of the culture zone, the currents of A7 and A8 sites located in the central of the culture zone decrease by almost 76% and 18%,respectively.
The Qinhuangdao coastal area is a significant passage through which the substance and energy are exchanged among the Liaodong Bay, the central of Bohai Sea and the Bohai Bay. In this paper, based on the in-situ current data obtained from seabed-based platform continuously in the Qinhuangdao coastal area in summer and autumn, we study the characteristics of current and its response to large-scale mariculture by means of harmonic analysis and filtering. The results are shown as follows:the most prominent semi-diurnal tidal current is the M2 tidal component with the maximum tidal velocity ranging from 20.0 cm/s to 36.9 cm/s, which is much smaller than the maximum velocity of M2 tidal current in the east side of Liaodong Bay. In autumn, the velocities of the residual currents in the Qinhuangdao coastal area, which are between 0.2 cm/s and 2.5 cm/s, are weaker than those in the east side of Liaodong Bay. Meanwhile, there may exist a weak clockwise circulation in the bottom of the Liaodong Bay. In summer,the maximum velocities of M2 and K1 tidal current components are larger than those in autumn. Aquaculture activities have a greater impact on the residual currents. Compared with the vertically-averaged residual current in site A6 which located at the edge of the culture zone, the currents of A7 and A8 sites located in the central of the culture zone decrease by almost 76% and 18%,respectively.
2019, 41(6): 37-47.
doi: 10.3969/j.issn.0253-4193.2019.06.004
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To study the sediment movement characteristics in a tidal channel, an one-dimensional depth-averaged suspended sediment concentration (SSC) model is established including advection, resuspension and deposition as main physical processes. The hydrodynamic force contains M2 and S2 tides. The model was applied in Meizhou Bay, in which tide, current, SSC and the sediment were measured or sampled in August, 2007. And the model was validated by the observation data. Suspension was decomposed into 12 primary terms by Fourier analysis, including (1) a demisemi-diurnal term induced by M2 tide with an angular velocity of the overtide of M2, (2) a demisemi-diurnal term induced by the combined action of M2 and S2 tides with an angular velocity of the sum of the angular velocities of M2 and S2, and (3) a semi-diurnal term induced by the combined action of horizontal suspension concentration gradient, residual current and M2 tide, with an angular velocity same to that of M2 tide. The time average of SSC is mainly controlled by residual current, horizontal gradient of suspension concentration, M2 tidal current, and the incipient condition of sediment. The residual current could cause the asymmetry of suspension between the adjacent periods. The feature of SSC curve is controlled by the sediment parameters which reflect the sediment characteristics. The deposition parameters influence both the phase and the amplitude of SSC. The resuspension parameters only influence the amplitude of SSC, nor did the phase.
To study the sediment movement characteristics in a tidal channel, an one-dimensional depth-averaged suspended sediment concentration (SSC) model is established including advection, resuspension and deposition as main physical processes. The hydrodynamic force contains M2 and S2 tides. The model was applied in Meizhou Bay, in which tide, current, SSC and the sediment were measured or sampled in August, 2007. And the model was validated by the observation data. Suspension was decomposed into 12 primary terms by Fourier analysis, including (1) a demisemi-diurnal term induced by M2 tide with an angular velocity of the overtide of M2, (2) a demisemi-diurnal term induced by the combined action of M2 and S2 tides with an angular velocity of the sum of the angular velocities of M2 and S2, and (3) a semi-diurnal term induced by the combined action of horizontal suspension concentration gradient, residual current and M2 tide, with an angular velocity same to that of M2 tide. The time average of SSC is mainly controlled by residual current, horizontal gradient of suspension concentration, M2 tidal current, and the incipient condition of sediment. The residual current could cause the asymmetry of suspension between the adjacent periods. The feature of SSC curve is controlled by the sediment parameters which reflect the sediment characteristics. The deposition parameters influence both the phase and the amplitude of SSC. The resuspension parameters only influence the amplitude of SSC, nor did the phase.
2019, 41(6): 48-63.
doi: 10.3969/j.issn.0253-4193.2019.06.005
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Identifying typhoon sequences on large time scales is of great scientific and practical significance to predict the super typhoon activities in the future. Although the high frequency of typhoon occurrence in Hainan Island in history is well known, it is difficult to determine the frequency of occurrence of the rare events like the Rammasun typhoon because of lack of detailed historical records. Here we use the sedimentary record, in combination with the information on the present-day events, i.e., the Rammasun typhoon, to define the typhoon intensity and identify the super typhoons that occurred in the past. A detailed field investigation was conducted in the coastal area near Wengtian Town, northeastern Hainan Island. We discovered storm beach-rock boulders and storm over-wash sediments interbedded within the coast dune sequence on the northeastern coast of Hainan Island. Base on laboratory and sediment dynamic analyses, we propose that the deposits were generated by super typhoon events, perhaps as early as 3 400 a BP. We find that the intensity of the typhoon that created these deposits was stronger than the Rammasun typhoon, which is of great significance to the reconstruction of typhoon sequences on millennial/centennial scales. Hydrodynamic analysis indicates that the wide reef flat in front of the beaches and coastal dunes plays a significant role in coast protection. Thus, the regional coral reef degeneration that is taking place now, together with likely intensified storms in response to climate change and future sea level rise, will become an enhanced risk of coastal erosion.
Identifying typhoon sequences on large time scales is of great scientific and practical significance to predict the super typhoon activities in the future. Although the high frequency of typhoon occurrence in Hainan Island in history is well known, it is difficult to determine the frequency of occurrence of the rare events like the Rammasun typhoon because of lack of detailed historical records. Here we use the sedimentary record, in combination with the information on the present-day events, i.e., the Rammasun typhoon, to define the typhoon intensity and identify the super typhoons that occurred in the past. A detailed field investigation was conducted in the coastal area near Wengtian Town, northeastern Hainan Island. We discovered storm beach-rock boulders and storm over-wash sediments interbedded within the coast dune sequence on the northeastern coast of Hainan Island. Base on laboratory and sediment dynamic analyses, we propose that the deposits were generated by super typhoon events, perhaps as early as 3 400 a BP. We find that the intensity of the typhoon that created these deposits was stronger than the Rammasun typhoon, which is of great significance to the reconstruction of typhoon sequences on millennial/centennial scales. Hydrodynamic analysis indicates that the wide reef flat in front of the beaches and coastal dunes plays a significant role in coast protection. Thus, the regional coral reef degeneration that is taking place now, together with likely intensified storms in response to climate change and future sea level rise, will become an enhanced risk of coastal erosion.
2019, 41(6): 64-75.
doi: 10.3969/j.issn.0253-4193.2019.06.006
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Based on the data collected from the International Bottom Trawl Surveys in the North Sea from 2001 to 2015,multivariate statistical analysis and other integrated indices are used to analyze the variation in the community structure of fish assemblage over time in the waters.The regime shift of fish population are also studied by the sequential t-test analysis of regime shifts (STARS). The analysis of the change in community structure is also conducted based on the factors of environment and fishing. The results show that 280 species had been caught, 222 of which are fish species. The abundance varies dramatically annually. Diversity has a general uptrend. Cluster and MDS show that the fifteen years could be divided into three groups of 2001-2003, 2004-2011 and 2012-2015. STARS of Discriminating species shows that there are two regime shift of the Atlantic herring in 2004 and 2014, which regime shift indexes (RSIs) are -0.45 and 0.41. There are two regime shifts of the haddock in 2003 and 2012, which RSIs are -0.58 and -0.66. There is one regime shift of the sprat in 2014, which RSI is 2. Through the analysis of environmental factors and fishing factors, we find that the first change of community structure is mainly affected by fishing factors. The second change of community structure is mainly affected by environmental factors.
Based on the data collected from the International Bottom Trawl Surveys in the North Sea from 2001 to 2015,multivariate statistical analysis and other integrated indices are used to analyze the variation in the community structure of fish assemblage over time in the waters.The regime shift of fish population are also studied by the sequential t-test analysis of regime shifts (STARS). The analysis of the change in community structure is also conducted based on the factors of environment and fishing. The results show that 280 species had been caught, 222 of which are fish species. The abundance varies dramatically annually. Diversity has a general uptrend. Cluster and MDS show that the fifteen years could be divided into three groups of 2001-2003, 2004-2011 and 2012-2015. STARS of Discriminating species shows that there are two regime shift of the Atlantic herring in 2004 and 2014, which regime shift indexes (RSIs) are -0.45 and 0.41. There are two regime shifts of the haddock in 2003 and 2012, which RSIs are -0.58 and -0.66. There is one regime shift of the sprat in 2014, which RSI is 2. Through the analysis of environmental factors and fishing factors, we find that the first change of community structure is mainly affected by fishing factors. The second change of community structure is mainly affected by environmental factors.
2019, 41(6): 76-84.
doi: 10.3969/j.issn.0253-4193.2019.06.007
Abstract:
The blood biochemical indexes were measured to evaluate the effects of acute hypoxia stress on body metabolism and tissue function of cobia (Rachycentron canadum). Results of this study are:(1) electrolyte content in serum increases in response to the acute hypoxia stress; serum ion concentrations of sodium, chloride and calcium are significantly changed(P<0.01), however, no significant difference on the level of potassium concentration was detected. (2) As for the indexes of liver function in cobia under acute hypoxic stress, the albumin content slightly decreases, the alanine aminotransferase and aspartate aminotransferase activities slightly increase; the total protein content is lower than those of the fish with no treatment (P<0.05). The albumin/globulin ratio is significantly higher than that before stress (P<0.05), while alkaline phosphatase is significantly different from that before stress (P<0.01). (3) After acute hypoxia stress, the concentrations of serum glucose and creatinine in cobia significantly increase (P<0.01). (4) Serum creatine kinase and lactate dehydrogenase activities increase under acute hypoxia stress. Creatine kinase activity is significantly different from that before stress (P<0.05), while lactate dehydrogenase activity is significantly different from that before stress (P<0.01). (5) After hypoxic stress, the changes of blood lipid indexes are different. Among them, the total cholesterol and high density lipoprotein concentrations show a very significant decrease (P<0.01). The concentration of low density lipoprotein increases significantly (P<0.05), and the concentration of triglyceride increases slightly, but it is not statistically significant (P>0.05). These results indicate that most of the blood biochemical indicators of cobia show significant changes after acute hypoxic stress, indicating that the liver, kidney and heart tissue may have been damaged.
The blood biochemical indexes were measured to evaluate the effects of acute hypoxia stress on body metabolism and tissue function of cobia (Rachycentron canadum). Results of this study are:(1) electrolyte content in serum increases in response to the acute hypoxia stress; serum ion concentrations of sodium, chloride and calcium are significantly changed(P<0.01), however, no significant difference on the level of potassium concentration was detected. (2) As for the indexes of liver function in cobia under acute hypoxic stress, the albumin content slightly decreases, the alanine aminotransferase and aspartate aminotransferase activities slightly increase; the total protein content is lower than those of the fish with no treatment (P<0.05). The albumin/globulin ratio is significantly higher than that before stress (P<0.05), while alkaline phosphatase is significantly different from that before stress (P<0.01). (3) After acute hypoxia stress, the concentrations of serum glucose and creatinine in cobia significantly increase (P<0.01). (4) Serum creatine kinase and lactate dehydrogenase activities increase under acute hypoxia stress. Creatine kinase activity is significantly different from that before stress (P<0.05), while lactate dehydrogenase activity is significantly different from that before stress (P<0.01). (5) After hypoxic stress, the changes of blood lipid indexes are different. Among them, the total cholesterol and high density lipoprotein concentrations show a very significant decrease (P<0.01). The concentration of low density lipoprotein increases significantly (P<0.05), and the concentration of triglyceride increases slightly, but it is not statistically significant (P>0.05). These results indicate that most of the blood biochemical indicators of cobia show significant changes after acute hypoxic stress, indicating that the liver, kidney and heart tissue may have been damaged.
2019, 41(6): 85-92.
doi: 10.3969/j.issn.0253-4193.2019.06.008
Abstract:
In order to investigate the temperature effects on the bacterivory of nanoflagellates (NF), natural NF community was collected from the coastal water in Guangxi, China. The NF was cultured under different temperatures (14℃, 22℃, and 28℃), during which the variations of the bacteria and NF abundance were observed. Fluorescently labeled bacteria were used to trace the grazing of bacteria by NF, and the community consumption rate of NF was calculated. Moreover, the ingestion rates of bacteria were compared between the PNF of different sizes (<3 μm and 3-10 μm). The results indicate that the ingestion rates arranged from high to low are 3-10 μm PNF, HNF, and <3 μm PNF. The ingestion rate of HNF is less affected by temperature than PNF, and the ingestion by PNF peaks at 22℃. Interestingly, the PNFs of the two sizes respond differently to temperature changes. The high temperature promotes the ingestion rate of 3-10 μm PNF but inhibits the ingestion rate of <3 μm PNF. The low temperature inhibits the ingestion rate of 3-10 μm PNF, but the inhibition of low temperature on the grazing of <3 μm PNF is less than high temperature. The abundances of both 3-10 μm PNF and <3 μm PNF are lowest in high temperature, and community consumption rate is mostly contributed by abundance. Therefore, for community consumption rate, the high temperature reduces the consumption of PNF on bacteria.
In order to investigate the temperature effects on the bacterivory of nanoflagellates (NF), natural NF community was collected from the coastal water in Guangxi, China. The NF was cultured under different temperatures (14℃, 22℃, and 28℃), during which the variations of the bacteria and NF abundance were observed. Fluorescently labeled bacteria were used to trace the grazing of bacteria by NF, and the community consumption rate of NF was calculated. Moreover, the ingestion rates of bacteria were compared between the PNF of different sizes (<3 μm and 3-10 μm). The results indicate that the ingestion rates arranged from high to low are 3-10 μm PNF, HNF, and <3 μm PNF. The ingestion rate of HNF is less affected by temperature than PNF, and the ingestion by PNF peaks at 22℃. Interestingly, the PNFs of the two sizes respond differently to temperature changes. The high temperature promotes the ingestion rate of 3-10 μm PNF but inhibits the ingestion rate of <3 μm PNF. The low temperature inhibits the ingestion rate of 3-10 μm PNF, but the inhibition of low temperature on the grazing of <3 μm PNF is less than high temperature. The abundances of both 3-10 μm PNF and <3 μm PNF are lowest in high temperature, and community consumption rate is mostly contributed by abundance. Therefore, for community consumption rate, the high temperature reduces the consumption of PNF on bacteria.
2019, 41(6): 93-102.
doi: 10.3969/j.issn.0253-4193.2019.06.009
Abstract:
The samples of copepods were collected from the estuary of Jiulong River during September 2013 to September 2017. One new species of Pseudodiaptomidae, Pseudodiaptomus sheni Guo & Wang, sp. nov., which had been identified as the saccupodus type of P. poplesia (Shen, 1955) by Chen and Zhang (1965) and Shen (1979), is described. The differences between this new species and P. poplesia are as follows:(1) cephalosome rounded anteriorly, while that of P. poplesia narrowly protruded in dorsal view; (2) female posterolateral corner with distinct bump postermedially; (3) the posterior process of female genital operculum pointed and longer than that of P. poplesia; (4) the outer terminal 2nd and 3rd setae basally swollen on female caudal rami; (5) the first exopod segment of female fifth leg with distomedial acute projection, while that of P. poplesia with blunt one; 6) medial triangular projection on the endopod of male left fifth leg elongated and longer than that of P. poplesia. The mitochondrial cytochrome oxidase subunit Ⅰ (mtCOI) gene sequences support the conclusion based on morphological data, with distinct divergence values 17.4% to 19.5% between P. sheni and P. poplesia. The new species is named in honor of Prof. Chia-jui Shen (1902-1975), a senior crustacean taxonomist of Institute of Zoology, Chinese Academy of Sciences. All type specimens are deposited in Museum of Marine Science and Technology, Xiamen University.
The samples of copepods were collected from the estuary of Jiulong River during September 2013 to September 2017. One new species of Pseudodiaptomidae, Pseudodiaptomus sheni Guo & Wang, sp. nov., which had been identified as the saccupodus type of P. poplesia (Shen, 1955) by Chen and Zhang (1965) and Shen (1979), is described. The differences between this new species and P. poplesia are as follows:(1) cephalosome rounded anteriorly, while that of P. poplesia narrowly protruded in dorsal view; (2) female posterolateral corner with distinct bump postermedially; (3) the posterior process of female genital operculum pointed and longer than that of P. poplesia; (4) the outer terminal 2nd and 3rd setae basally swollen on female caudal rami; (5) the first exopod segment of female fifth leg with distomedial acute projection, while that of P. poplesia with blunt one; 6) medial triangular projection on the endopod of male left fifth leg elongated and longer than that of P. poplesia. The mitochondrial cytochrome oxidase subunit Ⅰ (mtCOI) gene sequences support the conclusion based on morphological data, with distinct divergence values 17.4% to 19.5% between P. sheni and P. poplesia. The new species is named in honor of Prof. Chia-jui Shen (1902-1975), a senior crustacean taxonomist of Institute of Zoology, Chinese Academy of Sciences. All type specimens are deposited in Museum of Marine Science and Technology, Xiamen University.
2019, 41(6): 103-113.
doi: 10.3969/j.issn.0253-4193.2019.06.010
Abstract:
Infragravity waves (IGWs) are surface gravity waves with low frequency (0.005-0.05 Hz) and long wavelength (about 10 km). The sea surface elevation caused by IGWs can be captured by the future wide-swath altimeter Surface Water and Ocean Topography (SWOT). Thus, IGWs will be an important source of error, when using the observed sea surface elevation from SWOT to retrieve meso-and submeso-scale ocean circulation. Based on the spatial and temporal distribution of the global IGWs, the sea surface elevation caused by IGWs is estimated in the northeastern Pacific and northwestern Europe shelf with high IGW energy. Compared with the orbit noise simulated by SWOT Simulator (±5 cm), the IGW "noise" is quantitatively analyzed for the first time. We find that the sea surface elevation of the order of 1 cm contributed by IGWs is an important source of error that can not be ignored in the surface elevation measurements of SWOT. On the northwestern Europe continental shelf, the contribution of winter IGWs to sea surface elevation has reached 25% of the noise level requirement of SWOT. While, for the US west coast where the continental shelf is narrow, IGWs are generated along shorelines and quickly spread into the deep ocean, causing significant noise effects on a broader area, about 15% of the noise level requirement of SWOT.
Infragravity waves (IGWs) are surface gravity waves with low frequency (0.005-0.05 Hz) and long wavelength (about 10 km). The sea surface elevation caused by IGWs can be captured by the future wide-swath altimeter Surface Water and Ocean Topography (SWOT). Thus, IGWs will be an important source of error, when using the observed sea surface elevation from SWOT to retrieve meso-and submeso-scale ocean circulation. Based on the spatial and temporal distribution of the global IGWs, the sea surface elevation caused by IGWs is estimated in the northeastern Pacific and northwestern Europe shelf with high IGW energy. Compared with the orbit noise simulated by SWOT Simulator (±5 cm), the IGW "noise" is quantitatively analyzed for the first time. We find that the sea surface elevation of the order of 1 cm contributed by IGWs is an important source of error that can not be ignored in the surface elevation measurements of SWOT. On the northwestern Europe continental shelf, the contribution of winter IGWs to sea surface elevation has reached 25% of the noise level requirement of SWOT. While, for the US west coast where the continental shelf is narrow, IGWs are generated along shorelines and quickly spread into the deep ocean, causing significant noise effects on a broader area, about 15% of the noise level requirement of SWOT.
2019, 41(6): 114-122.
doi: 10.3969/j.issn.0253-4193.2019.06.011
Abstract:
Atmospheric deposition of 210Po and 210Pb were measured at a time-series station in the southeast of China (Xiamen) from 2013 to 2014. The daily deposition fluxes of 210Po and 210Pb are (65.38±4.79)mBq/(m2·d) and (0.78±0.09)Bq/(m2·d), respectively, and the flux values present a significant annual variation. High fluxes occur in months with northeast monsoon, and low values are observed in the southwest monsoon prevailing months. In 2013 and 2014, the yearly deposition fluxes of 210Po are 19.29 Bq/(m2·a) and 9.25 Bq/(m2·a), and 210Pb fluxes are 159.2 Bq/(m2·a) and 189.6 Bq/(m2·a), respectively. The deposition fluxes of 210Po and 210Pb show inter-annual variations. There is a significant linear positive correlation between the 210Po and 210Pb fluxes. In addition, good positive correlations between rainfall and the deposition fluxes of the two nuclides are observed. These results reveal that the predominant removal passage of 210Po and 210Pb is precipitation along with rainfall, providing insights into understanding the transport of aerosol via 210Po and 210Pb. The datasets would provide an atmospheric source term for budgeting 210Po and 210Pb in waters of the western Taiwan Strait.
Atmospheric deposition of 210Po and 210Pb were measured at a time-series station in the southeast of China (Xiamen) from 2013 to 2014. The daily deposition fluxes of 210Po and 210Pb are (65.38±4.79)mBq/(m2·d) and (0.78±0.09)Bq/(m2·d), respectively, and the flux values present a significant annual variation. High fluxes occur in months with northeast monsoon, and low values are observed in the southwest monsoon prevailing months. In 2013 and 2014, the yearly deposition fluxes of 210Po are 19.29 Bq/(m2·a) and 9.25 Bq/(m2·a), and 210Pb fluxes are 159.2 Bq/(m2·a) and 189.6 Bq/(m2·a), respectively. The deposition fluxes of 210Po and 210Pb show inter-annual variations. There is a significant linear positive correlation between the 210Po and 210Pb fluxes. In addition, good positive correlations between rainfall and the deposition fluxes of the two nuclides are observed. These results reveal that the predominant removal passage of 210Po and 210Pb is precipitation along with rainfall, providing insights into understanding the transport of aerosol via 210Po and 210Pb. The datasets would provide an atmospheric source term for budgeting 210Po and 210Pb in waters of the western Taiwan Strait.
2019, 41(6): 123-134.
doi: 10.3969/j.issn.0253-4193.2019.06.012
Abstract:
Based on the National Key Basic Research (973) project, the response and modulation of the upper ocean to typhoon, an air-sea-wave coupling model system for typhoon intensity prediction was established by Shanghai Typhoon Institute of the China Meteorological Administration cooperating with some of units belong to the National Oceanic Administration. This system shows good performance for the historical typhoon cases simulation and prediction during the typhoon seasons in 2016 and 2017. The key measures and achievements include the implementation of field observation scientific experiments of typhoon over the sea and coastal area, observational study of the air-sea interaction and improvement of the parameterization scheme in the boundary layer of model. Also the ensemble prediction technique of typhoon intensity is developed on this basis.
Based on the National Key Basic Research (973) project, the response and modulation of the upper ocean to typhoon, an air-sea-wave coupling model system for typhoon intensity prediction was established by Shanghai Typhoon Institute of the China Meteorological Administration cooperating with some of units belong to the National Oceanic Administration. This system shows good performance for the historical typhoon cases simulation and prediction during the typhoon seasons in 2016 and 2017. The key measures and achievements include the implementation of field observation scientific experiments of typhoon over the sea and coastal area, observational study of the air-sea interaction and improvement of the parameterization scheme in the boundary layer of model. Also the ensemble prediction technique of typhoon intensity is developed on this basis.
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