2015 Vol. 37, No. 4
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2015, 37(4): .
Abstract:
2015, 37(4): 1-15.
doi: 10.3969/j.issn.0253-4193.2015.04.001
Abstract:
Knowledge of the transport of particulate organic carbon in large-river estuaries from the perspective of size-fractionation is key to better understand the biogeochemical processes of organic carbon during the mixing of freshwater and seawater. Suspended particulate matters (SPM) in surface water were collected along a salinity gradient in the turbidity maximum zone of the Changjiang Estuary in June 2011,and then were separated into different size fractions using the water elutriation method. Organic carbon (OC) and nitrogen,stable carbon isotopic composition and specific surface area (SSA) of these size-fractionated particles were analyzed to discuss the variation of sources,distribution and preservation of OC with the increasing salinity and their impact factors. The results showed that with the increase of salinity and particle size,the size-fractionated particulate OC (POC) gradually reduced and mainly concentrated in less than 32 μm fractions. The POC in the estuary was lower than those in the main stream,perhaps due to the special biogeochemical processes around the maximum turbidity zone,such as flocculating and settling of fine particles,microbial decomposition,etc. The results of the three end-member mixing model based on Monte-Carlo simulation indicated that the POC was mainly from riverine and deltaic sources,whereas the contribution from marine end-member was relatively small,and the average fractions of these three end-members were 40%,35% and 25%,respectively. In the freshwater end,deltaic OC of the size fractions increased with the increase of salinity,but in the seawater end,the contribution of marine OC increased,especially in the 16-32 μm fractions,with the maximum value of 39%. The SSA normalized OC contents of the 32—63μm fractions were all larger than 1.0 mg/m2,while the OC/SSA ratios of less than 32 μm fractions were in the range of 0.4 to 1.0 mg/m2,consistent with the typical characteristics of river suspended particulates. Furthermore,the OC/SSA ratios also indicated that OC in fine particulates could have been decomposed in a certain degree. However,these ratios were generally higher than those of the surface sediments in the Changjiang Estuary,which indicated that particulate OC may go through further remineralization during or after sedimentation. Preliminary estimate showed that 71% of the terrigenous OC delivered by the Changjiang was lost during sedimentation. This study helps to deeply understand the role of particulate matters with different sizes in the transport and transformation of OC in large-river estuaries,and deepen the knowledge of biogeochemical processes of OC in high turbidity estuary.
Knowledge of the transport of particulate organic carbon in large-river estuaries from the perspective of size-fractionation is key to better understand the biogeochemical processes of organic carbon during the mixing of freshwater and seawater. Suspended particulate matters (SPM) in surface water were collected along a salinity gradient in the turbidity maximum zone of the Changjiang Estuary in June 2011,and then were separated into different size fractions using the water elutriation method. Organic carbon (OC) and nitrogen,stable carbon isotopic composition and specific surface area (SSA) of these size-fractionated particles were analyzed to discuss the variation of sources,distribution and preservation of OC with the increasing salinity and their impact factors. The results showed that with the increase of salinity and particle size,the size-fractionated particulate OC (POC) gradually reduced and mainly concentrated in less than 32 μm fractions. The POC in the estuary was lower than those in the main stream,perhaps due to the special biogeochemical processes around the maximum turbidity zone,such as flocculating and settling of fine particles,microbial decomposition,etc. The results of the three end-member mixing model based on Monte-Carlo simulation indicated that the POC was mainly from riverine and deltaic sources,whereas the contribution from marine end-member was relatively small,and the average fractions of these three end-members were 40%,35% and 25%,respectively. In the freshwater end,deltaic OC of the size fractions increased with the increase of salinity,but in the seawater end,the contribution of marine OC increased,especially in the 16-32 μm fractions,with the maximum value of 39%. The SSA normalized OC contents of the 32—63μm fractions were all larger than 1.0 mg/m2,while the OC/SSA ratios of less than 32 μm fractions were in the range of 0.4 to 1.0 mg/m2,consistent with the typical characteristics of river suspended particulates. Furthermore,the OC/SSA ratios also indicated that OC in fine particulates could have been decomposed in a certain degree. However,these ratios were generally higher than those of the surface sediments in the Changjiang Estuary,which indicated that particulate OC may go through further remineralization during or after sedimentation. Preliminary estimate showed that 71% of the terrigenous OC delivered by the Changjiang was lost during sedimentation. This study helps to deeply understand the role of particulate matters with different sizes in the transport and transformation of OC in large-river estuaries,and deepen the knowledge of biogeochemical processes of OC in high turbidity estuary.
2015, 37(4): 16-27.
doi: 10.3969/j.issn.0253-4193.2015.04.002
Abstract:
In order to understand the impact of spring bloom on the biogeochemical behavior of arsenic (a toxic metalloid element) in the South Yellow Sea (SYS),the field investigation was carried out during March 30th to April 23rd 2007 to study the concentrations and distributions of total dissolved inorganic arsenic (TDIAs,[TDIAs]=[As5+]+[As3+]) in the SYS. In addition,a 25 h anchor station (BM1) was also carried out at the central of SYS,where Chl a concentrations were higher than 4 μg/L. The concentrations of TDIAs were measured by Hydride Generation-Atomic Fluorescence Spectrometry (HG-AFS) and showed the range of 7.9-22.3 nmol/L,with the average of (17.8±1.9) nmol/L. The concentrations of TDIAs increased gradually from the coastal area to offshore,with the maximum values appearing at the near bottom layer of the southern region. The concentrations of TDIAs showed well mixed vertical profile in the coastal area,while was stratified in the middle and southern region. Due to the impact of strong dust storm and followed rainfall in the SYS during the investigation of March 31st to April 1st 2007,the concentrations of TDIAs in the surface waters were significant increased. A large-scale spring bloom occurred in the middle and southern region of study area for 4-5 days after the dust storm. Through the observations it can be found that the vertical profiles of TDIAs was similar to that of phosphate,and showed relatively negative relationships with chlorophyll a(r=0.51,p <0.05,n=39). After primary estimation,the scavenging of TDIAs by phytoplankton above 10 meters layer can reach up to 2.4 nmol/L,which account for 15% of that in the surface waters. The residence time of TDIAs in the YS was (15.6±7.3) a,which is much lower than the open oceans. The molar ratio of arsenic to phosphorus in the study area was about 20 times higher than the open ocean,which might lead to significant absorption and transformation of arsenate and cause the potential ecological crisis.
In order to understand the impact of spring bloom on the biogeochemical behavior of arsenic (a toxic metalloid element) in the South Yellow Sea (SYS),the field investigation was carried out during March 30th to April 23rd 2007 to study the concentrations and distributions of total dissolved inorganic arsenic (TDIAs,[TDIAs]=[As5+]+[As3+]) in the SYS. In addition,a 25 h anchor station (BM1) was also carried out at the central of SYS,where Chl a concentrations were higher than 4 μg/L. The concentrations of TDIAs were measured by Hydride Generation-Atomic Fluorescence Spectrometry (HG-AFS) and showed the range of 7.9-22.3 nmol/L,with the average of (17.8±1.9) nmol/L. The concentrations of TDIAs increased gradually from the coastal area to offshore,with the maximum values appearing at the near bottom layer of the southern region. The concentrations of TDIAs showed well mixed vertical profile in the coastal area,while was stratified in the middle and southern region. Due to the impact of strong dust storm and followed rainfall in the SYS during the investigation of March 31st to April 1st 2007,the concentrations of TDIAs in the surface waters were significant increased. A large-scale spring bloom occurred in the middle and southern region of study area for 4-5 days after the dust storm. Through the observations it can be found that the vertical profiles of TDIAs was similar to that of phosphate,and showed relatively negative relationships with chlorophyll a(r=0.51,p <0.05,n=39). After primary estimation,the scavenging of TDIAs by phytoplankton above 10 meters layer can reach up to 2.4 nmol/L,which account for 15% of that in the surface waters. The residence time of TDIAs in the YS was (15.6±7.3) a,which is much lower than the open oceans. The molar ratio of arsenic to phosphorus in the study area was about 20 times higher than the open ocean,which might lead to significant absorption and transformation of arsenate and cause the potential ecological crisis.
2015, 37(4): 28-39.
doi: 10.3969/j.issn.0253-4193.2015.04.003
Abstract:
The sagittae morphological characteristics of three species Sebastes hubbsi,S.nigricans and S.schlegelii from Jiaozhou Bay,Qingdao,were analyzed to test the hypothesis that the three Sebastes species could be identified by their sagittae morphology and to find out which method was more appropriate. Eight otolith shape indices and 37 elliptical Fourier coefficients (eFcs) were analyzed,and results showed that the difference in the sagittae morphology between S. hubbsi and S. schlegelii were the largest,and those between S. hubbsi and S. nigricans were the least. In the discriminant analyses of the three species,discriminating rates of more than 95% were obtained and they were clearly sorted in scatter plots when using the otolith shape indices,the eFcs,as well as a combination of the two. When applied to the three species of which otolith was 4 to 7 mm and those were more than two years old,the species identification based on the otolith morphology was proved to be feasible: when only using the eFcs,a 100% of discriminating rate was obtained but this method couldn't quickly locate the shape which was tiny in fact but significant difference among the sagittae of the three Sebastes in statistics. Combing otolith shape indices and the eFcs could not only obtain a high classification rate of about 99%,but also identify the differences in the rectangularity,form-factor and surface density among the three Sebastes sagittae. The results showed that combing shape indices analysis and elliptical Fourier analysis was the effective method for species discrimination of genus Sebastes and it can find out the differences of the sagittae of the three Sebastes.
The sagittae morphological characteristics of three species Sebastes hubbsi,S.nigricans and S.schlegelii from Jiaozhou Bay,Qingdao,were analyzed to test the hypothesis that the three Sebastes species could be identified by their sagittae morphology and to find out which method was more appropriate. Eight otolith shape indices and 37 elliptical Fourier coefficients (eFcs) were analyzed,and results showed that the difference in the sagittae morphology between S. hubbsi and S. schlegelii were the largest,and those between S. hubbsi and S. nigricans were the least. In the discriminant analyses of the three species,discriminating rates of more than 95% were obtained and they were clearly sorted in scatter plots when using the otolith shape indices,the eFcs,as well as a combination of the two. When applied to the three species of which otolith was 4 to 7 mm and those were more than two years old,the species identification based on the otolith morphology was proved to be feasible: when only using the eFcs,a 100% of discriminating rate was obtained but this method couldn't quickly locate the shape which was tiny in fact but significant difference among the sagittae of the three Sebastes in statistics. Combing otolith shape indices and the eFcs could not only obtain a high classification rate of about 99%,but also identify the differences in the rectangularity,form-factor and surface density among the three Sebastes sagittae. The results showed that combing shape indices analysis and elliptical Fourier analysis was the effective method for species discrimination of genus Sebastes and it can find out the differences of the sagittae of the three Sebastes.
2015, 37(4): 40-51.
doi: 10.3969/j.issn.0253-4193.2015.04.004
Abstract:
Paralichthys olivaceus is the major species for marine aquaculture and fisheries on the western Pacific coast. Due to the high disease incidence and slow growth rate observed in artificial-breeding programs,the selective breeding of Japanese flounder has been pursued since the beginning of this century. Here,we established 52 F3 families based on the screened F1 and F2 core families that we bred previously. Approximately 196 days after hatching,we measured five growth traits of 1 560 fry from the 52 families,for a total of 7 800 data points. An "A-D" model and MINQUE were used to estimate the marginal mean,additive-variance component,dominance-variance component,random-variance component,narrow-sense heritability,broad-sense heritability,parental additive effect and random hybridization effect of each trait. The additive-variance component ratios of the five traits were between (0.099±0.01) and (0.24±0.02); the dominance-variance component ratios were between (0.30±0.02) and (0.31±0.02); the random-variance component ratios were between (0.48±0.02) and (0.61±0.01); the narrow-sense heritabilities were between 0.099 and 0.24; and the broad-sense heritabilities were between 0.38 and 0.54. Each of these genetic parameters showed highly significant differences (p <0.01). The random dominance effects of 42 crosses were predicted,and D(2×6),D(2×18),D(3×4),D(7×12),D(7×14) and D(8×13) all showed highly significant positive effects (p <0.01) on the five traits. The results of this study provide a preliminary set of optimal parental lines,crosses and families to establish improved Japanese flounder strains. These results also provide a theoretical and technical foundation for further selective breeding.
Paralichthys olivaceus is the major species for marine aquaculture and fisheries on the western Pacific coast. Due to the high disease incidence and slow growth rate observed in artificial-breeding programs,the selective breeding of Japanese flounder has been pursued since the beginning of this century. Here,we established 52 F3 families based on the screened F1 and F2 core families that we bred previously. Approximately 196 days after hatching,we measured five growth traits of 1 560 fry from the 52 families,for a total of 7 800 data points. An "A-D" model and MINQUE were used to estimate the marginal mean,additive-variance component,dominance-variance component,random-variance component,narrow-sense heritability,broad-sense heritability,parental additive effect and random hybridization effect of each trait. The additive-variance component ratios of the five traits were between (0.099±0.01) and (0.24±0.02); the dominance-variance component ratios were between (0.30±0.02) and (0.31±0.02); the random-variance component ratios were between (0.48±0.02) and (0.61±0.01); the narrow-sense heritabilities were between 0.099 and 0.24; and the broad-sense heritabilities were between 0.38 and 0.54. Each of these genetic parameters showed highly significant differences (p <0.01). The random dominance effects of 42 crosses were predicted,and D(2×6),D(2×18),D(3×4),D(7×12),D(7×14) and D(8×13) all showed highly significant positive effects (p <0.01) on the five traits. The results of this study provide a preliminary set of optimal parental lines,crosses and families to establish improved Japanese flounder strains. These results also provide a theoretical and technical foundation for further selective breeding.
2015, 37(4): 52-61.
doi: 10.3969/j.issn.0253-4193.2015.04.005
Abstract:
The brown morphotype of red seaweed Kappaphycus alvarezii collected from Li'an Bay in Lingshui County,Hainan Province of China,was used as explants in order to generate new buds and induce callus. Effect of the PES (Provasoli enriched seawater) media (with or without gelling agent),light intensity,and phytoregulators (Indole-3-acetic acid (IAA),Indole-3-butyric acid (IBA),6-benzylaminopurine (6-BA)) were tested on new bud generation and callus formation by orthogonality experiment. The callus forming was observed in microscope,and the changes of the respiration rate and photosynthesis rate in explants among callus forming were detected. The callus of Kappaphycus alvarezii was achieved successfully by the combination of PES solid medium (0.8% ager),IBA,6-BA,while callus was not observed in the combination of PES liqiud medium,IBA and 6-BA. That indicates the solid medium plays an important role in callus induction. Kappaphycus alvarezii callus which consists of compact filamentous cells was different from the loose callus of superior plants. And callus derived from the medullary cells. It was found that both photosynthetic rate and respiratory rate in the branch inducing callus were higher than ones of the branch germinating new bud by means of oxygen electrode.
The brown morphotype of red seaweed Kappaphycus alvarezii collected from Li'an Bay in Lingshui County,Hainan Province of China,was used as explants in order to generate new buds and induce callus. Effect of the PES (Provasoli enriched seawater) media (with or without gelling agent),light intensity,and phytoregulators (Indole-3-acetic acid (IAA),Indole-3-butyric acid (IBA),6-benzylaminopurine (6-BA)) were tested on new bud generation and callus formation by orthogonality experiment. The callus forming was observed in microscope,and the changes of the respiration rate and photosynthesis rate in explants among callus forming were detected. The callus of Kappaphycus alvarezii was achieved successfully by the combination of PES solid medium (0.8% ager),IBA,6-BA,while callus was not observed in the combination of PES liqiud medium,IBA and 6-BA. That indicates the solid medium plays an important role in callus induction. Kappaphycus alvarezii callus which consists of compact filamentous cells was different from the loose callus of superior plants. And callus derived from the medullary cells. It was found that both photosynthetic rate and respiratory rate in the branch inducing callus were higher than ones of the branch germinating new bud by means of oxygen electrode.
2015, 37(4): 62-75.
doi: 10.3969/j.issn.0253-4193.2015.04.006
Abstract:
An ecological survey was carried out in July 2013 in the Yellow River adjacent sea after the 16th water-sediment regulation,with an aim of understanding the response of phytoplankton assemblages to changed environment. The result showed that temperature and nutrient concentrations decreased gradually from the mouth of river to offshore waters,corresponding to the increased freshwater loading,and salinity increased gradually from the mouth of river to offshore waters. Nutrient concentrations at the sites near to the side of Bohai Bay displayed higher values than the Laizhou Bay. The analysis on nutrient structure indicated that DIP was absolute and relative limitation,while DSi limitation only appeared in a few sites. 100 species of phytoplankton in 60 genera of the five classes were identified from the samples,and major phytoplankton components were diatoms and dinoflagellates. In addition,a few brackish species in Cyanophyceae,Chrysophyceae,and Chlorophyceae were also identified from the river mouth,indicating the impact of salinity. Chlorophyll a concentrations and nutrient concentrations presented a significantly spatial distribution from the river mouth to offshore waters,with higher values at the sites near to the side of the Bohai Bay than the Laizhou Bay. Phytoplankton assemblages were in response to the variations of spatial environmental factors. The biomass proportions of Cyanophyceae and Chlorophyceae increased distinctly in the transections of C,D and E,indicating a strong influence of the diluted water,while diatoms and dinoflagellates in other transections with less impact from the diluted water. The results of Principal Components Analysis between phytoplankton assemblages and environmental factors indicated that DSi,DIP and salinity were key factors related to the spatial variation of phytoplankton assemblages.
An ecological survey was carried out in July 2013 in the Yellow River adjacent sea after the 16th water-sediment regulation,with an aim of understanding the response of phytoplankton assemblages to changed environment. The result showed that temperature and nutrient concentrations decreased gradually from the mouth of river to offshore waters,corresponding to the increased freshwater loading,and salinity increased gradually from the mouth of river to offshore waters. Nutrient concentrations at the sites near to the side of Bohai Bay displayed higher values than the Laizhou Bay. The analysis on nutrient structure indicated that DIP was absolute and relative limitation,while DSi limitation only appeared in a few sites. 100 species of phytoplankton in 60 genera of the five classes were identified from the samples,and major phytoplankton components were diatoms and dinoflagellates. In addition,a few brackish species in Cyanophyceae,Chrysophyceae,and Chlorophyceae were also identified from the river mouth,indicating the impact of salinity. Chlorophyll a concentrations and nutrient concentrations presented a significantly spatial distribution from the river mouth to offshore waters,with higher values at the sites near to the side of the Bohai Bay than the Laizhou Bay. Phytoplankton assemblages were in response to the variations of spatial environmental factors. The biomass proportions of Cyanophyceae and Chlorophyceae increased distinctly in the transections of C,D and E,indicating a strong influence of the diluted water,while diatoms and dinoflagellates in other transections with less impact from the diluted water. The results of Principal Components Analysis between phytoplankton assemblages and environmental factors indicated that DSi,DIP and salinity were key factors related to the spatial variation of phytoplankton assemblages.
2015, 37(4): 76-82.
doi: 10.3969/j.issn.0253-4193.2015.04.007
Abstract:
Constant False Alarm Rate (CFAR) detection is the main method used in the ship detection of High Frequency Surface Wave Radar (HFSWR). The present Automatic Identification System (AIS) based verification methods of CFAR results is an indirect method,which are subject to the influence of the direction estimation error and lack of the ability of analyzing the situations of false target and miss detection. In this paper,we introduced a direct method to evaluate the CFAR ship detection results of HFSWR based on range-Doppler projection of AIS data. The AIS data were converted and presented on the range-Doppler spectrum of HFSWR. These information were then associated with the CFAR results to facilitate direct evaluation. The principle and procedure of our method were introduced in detail,and the practical applications in CFAR results of field data were provided. It was demonstrated to be an effective verification method. Moreover,it could contribute to the parameter adjustment of CFAR in detection of low observable targets.
Constant False Alarm Rate (CFAR) detection is the main method used in the ship detection of High Frequency Surface Wave Radar (HFSWR). The present Automatic Identification System (AIS) based verification methods of CFAR results is an indirect method,which are subject to the influence of the direction estimation error and lack of the ability of analyzing the situations of false target and miss detection. In this paper,we introduced a direct method to evaluate the CFAR ship detection results of HFSWR based on range-Doppler projection of AIS data. The AIS data were converted and presented on the range-Doppler spectrum of HFSWR. These information were then associated with the CFAR results to facilitate direct evaluation. The principle and procedure of our method were introduced in detail,and the practical applications in CFAR results of field data were provided. It was demonstrated to be an effective verification method. Moreover,it could contribute to the parameter adjustment of CFAR in detection of low observable targets.
2015, 37(4): 83-93.
doi: 10.3969/j.issn.0253-4193.2015.04.008
Abstract:
Sulfate reduction rates were measured experimentally with 35SO42- in sediment of A and B cores in coastal of Jiulong River Estuary in July of 2011. A and B cores were situated in the upper estuarine coast and seaward boundary respectively,with low salinity (3-5) and high salinity (20-25). Sulfate reduction rates volume-based values ranged from 54 to 2 345 nmol/(cm3·d) in vertical profile of A core,and the highest sulfate reduction rates occurred at 20 cm depth. Sulfate reduction rates varied from 24 to 987 nmol/(cm3·d) in B core,two peaks in sulfate reduction rates profiles obviously appeared on the top 10 cm and at 78cm depth,with significantly high value of 876 nmol/(cm3·d) and 987 nmol/(cm3·d),respectively. Based on trends on the vertical profile of SO42-,methane concentration in pore water and total organic carbon,temperature and oxidation reduction potential in sediments of two cores,sulfate reduction is mainly dominated by organic mineralization in A Core,however sulfate reduction is controlled by the combination of organic matter mineralization and anaerobic methane oxidation in B Core. Meanwhile sulfate reduction rates and the vertical distribution trends of it were affected by the availability of active organic matter,temperature and SO42- concentration in the pore water in two cores. The depth-integrated sulfate reduction rates were 527.9 mmol/(m2·d) and 357.1 mmol/(m2·d) within sulfate reduction zone in A Core and B Core respectively. Sulfate reduction is one of the major processes contributing to the mineralization of organic matter in this estuary.
Sulfate reduction rates were measured experimentally with 35SO42- in sediment of A and B cores in coastal of Jiulong River Estuary in July of 2011. A and B cores were situated in the upper estuarine coast and seaward boundary respectively,with low salinity (3-5) and high salinity (20-25). Sulfate reduction rates volume-based values ranged from 54 to 2 345 nmol/(cm3·d) in vertical profile of A core,and the highest sulfate reduction rates occurred at 20 cm depth. Sulfate reduction rates varied from 24 to 987 nmol/(cm3·d) in B core,two peaks in sulfate reduction rates profiles obviously appeared on the top 10 cm and at 78cm depth,with significantly high value of 876 nmol/(cm3·d) and 987 nmol/(cm3·d),respectively. Based on trends on the vertical profile of SO42-,methane concentration in pore water and total organic carbon,temperature and oxidation reduction potential in sediments of two cores,sulfate reduction is mainly dominated by organic mineralization in A Core,however sulfate reduction is controlled by the combination of organic matter mineralization and anaerobic methane oxidation in B Core. Meanwhile sulfate reduction rates and the vertical distribution trends of it were affected by the availability of active organic matter,temperature and SO42- concentration in the pore water in two cores. The depth-integrated sulfate reduction rates were 527.9 mmol/(m2·d) and 357.1 mmol/(m2·d) within sulfate reduction zone in A Core and B Core respectively. Sulfate reduction is one of the major processes contributing to the mineralization of organic matter in this estuary.
2015, 37(4): 94-102.
doi: 10.3969/j.issn.0253-4193.2015.04.009
Abstract:
In order to know the relationship between body mass and morphometric traits in the half smooth tongue sole (Cynoglossus semilaevis),body mass [BM(g)] and three morphometric traits,e.g.,total length [TL(cm)],body height [BH(cm)] and body width [BW(cm)] of 831 individuals of 12 months old Cynoglossus semilaevis were measured in this study. The best models for female and male individuals reflecting the relationship between each morphometric trait and body mass were obtained through model fitting screening,respectively. We established the regression equation with morphological traits as variables and body mass as the dependent variable and calculated the direct and indirect path coefficient and the coefficient of determination. The results showed that the best model fitted for female individuals was ŷ =0.004x3.090 for TL-BM, ŷ =0.382x2.983 for BH-BM and ŷ =61.912x2.461 for BW-BM. And for male animals,they were ŷ =0.005x3.003 for TL-BM, ŷ =0.300x3.147 for BH-BM and ŷ =57.681x2.156 for BW-BM. Path analysis showed that BH was the most predominant variable to affect BM (0.535) in females,while TL was the largest effect to BM (0.407) in males. Three morphological traits of female and male individuals were all extremely remarkable effects on the body mass. The multiple linear regression model equation were established as BM=-88.530+1.297TL+15.862BH+39.021BW for females,and BM=-71.579+2.587TL+7.351BH+35.595BW for males.
In order to know the relationship between body mass and morphometric traits in the half smooth tongue sole (Cynoglossus semilaevis),body mass [BM(g)] and three morphometric traits,e.g.,total length [TL(cm)],body height [BH(cm)] and body width [BW(cm)] of 831 individuals of 12 months old Cynoglossus semilaevis were measured in this study. The best models for female and male individuals reflecting the relationship between each morphometric trait and body mass were obtained through model fitting screening,respectively. We established the regression equation with morphological traits as variables and body mass as the dependent variable and calculated the direct and indirect path coefficient and the coefficient of determination. The results showed that the best model fitted for female individuals was ŷ =0.004x3.090 for TL-BM, ŷ =0.382x2.983 for BH-BM and ŷ =61.912x2.461 for BW-BM. And for male animals,they were ŷ =0.005x3.003 for TL-BM, ŷ =0.300x3.147 for BH-BM and ŷ =57.681x2.156 for BW-BM. Path analysis showed that BH was the most predominant variable to affect BM (0.535) in females,while TL was the largest effect to BM (0.407) in males. Three morphological traits of female and male individuals were all extremely remarkable effects on the body mass. The multiple linear regression model equation were established as BM=-88.530+1.297TL+15.862BH+39.021BW for females,and BM=-71.579+2.587TL+7.351BH+35.595BW for males.
2015, 37(4): 103-116.
doi: 10.3969/j.issn.0253-4193.2015.04.010
Abstract:
Temporal and spatial variations of surface seawater temperature (SST),salinity (SSS),nutrient concentrations and chlorophyll a concentrations were studied in April,June,August and October 2010 and January and March 2011 in Jiaozhou Bay. Spatial distributions showed that dissolved inorganic nitrogen (DIN),phosphate (PO4) and silicate (SiO3) concentrations were higher in the northeast edge and decreased gradually towards the inner and the mouth of Jiaozhou Bay during most time of study. DIN and PO4 were relatively higher in early summer and autumn but lower in winter and late summer as a result of the effects from aquaculture,exogenous nutrients input and phytoplankton consumption. SiO3 concentrations were mainly affected by phytoplankton consumption and river loadings and were higher in summer and autumn and lower in spring and winter. The analysis on concentrations and structures of nutrients of Jiaozhou Bay during the study period indicated that PO4 and SiO3 were both absolute and relative limitations,and SiO3 limitation was more serious and acted as the important factor which controlled the growth of phytoplankton all over the year. The most serious limitation of SiO3 and PO4 occurred in winter and was found in the whole bay. The nutrient loadings as a result of rainfall in summer,however,relieved SiO3 limitation. The chlorophyll a concentrations were higher in spring and summer and lower in autumn and winter. Temperature,nutrients and the ingestion of filter mussels were the dominant effect factors of the concentrations and distribution of chlorophyll a.
Temporal and spatial variations of surface seawater temperature (SST),salinity (SSS),nutrient concentrations and chlorophyll a concentrations were studied in April,June,August and October 2010 and January and March 2011 in Jiaozhou Bay. Spatial distributions showed that dissolved inorganic nitrogen (DIN),phosphate (PO4) and silicate (SiO3) concentrations were higher in the northeast edge and decreased gradually towards the inner and the mouth of Jiaozhou Bay during most time of study. DIN and PO4 were relatively higher in early summer and autumn but lower in winter and late summer as a result of the effects from aquaculture,exogenous nutrients input and phytoplankton consumption. SiO3 concentrations were mainly affected by phytoplankton consumption and river loadings and were higher in summer and autumn and lower in spring and winter. The analysis on concentrations and structures of nutrients of Jiaozhou Bay during the study period indicated that PO4 and SiO3 were both absolute and relative limitations,and SiO3 limitation was more serious and acted as the important factor which controlled the growth of phytoplankton all over the year. The most serious limitation of SiO3 and PO4 occurred in winter and was found in the whole bay. The nutrient loadings as a result of rainfall in summer,however,relieved SiO3 limitation. The chlorophyll a concentrations were higher in spring and summer and lower in autumn and winter. Temperature,nutrients and the ingestion of filter mussels were the dominant effect factors of the concentrations and distribution of chlorophyll a.
2015, 37(4): 117-123.
doi: 10.3969/j.issn.0253-4193.2015.04.011
Abstract:
Based on the morphologic difference of spire,Oliva snails with similar shell colors and patterns can be divided into two morphotypes. Morphotype Ⅰ is characterized by the sunk spire in its concavity below the shoulder of the body whorl and the whorls of spire fused together. Morphotype Ⅱ shows the identical conchological characteristics of typical specimens of O. mustelina. The mitochondrial cytochrome c oxidase subunit Ⅰ (COⅠ) and 16S rRNA gene segments of these two morphotypes were sequenced. Genetic analyses clearly showed many common haplotypes and lack of significant genetic differentiation between the two morphotypes. In addition,further phylogenetic analyses showed that all haplotypes were grouped in a monophyletic clade. Thus,the two morphotypes are not genetically diagnosable,and therefore should be assigned to species O. mustelina. Morphotype Ⅰ may be a new form of O. mustelina that differ from the typical specimens.
Based on the morphologic difference of spire,Oliva snails with similar shell colors and patterns can be divided into two morphotypes. Morphotype Ⅰ is characterized by the sunk spire in its concavity below the shoulder of the body whorl and the whorls of spire fused together. Morphotype Ⅱ shows the identical conchological characteristics of typical specimens of O. mustelina. The mitochondrial cytochrome c oxidase subunit Ⅰ (COⅠ) and 16S rRNA gene segments of these two morphotypes were sequenced. Genetic analyses clearly showed many common haplotypes and lack of significant genetic differentiation between the two morphotypes. In addition,further phylogenetic analyses showed that all haplotypes were grouped in a monophyletic clade. Thus,the two morphotypes are not genetically diagnosable,and therefore should be assigned to species O. mustelina. Morphotype Ⅰ may be a new form of O. mustelina that differ from the typical specimens.
2015, 37(4): 124-133.
doi: 10.3969/j.issn.0253-4193.2015.04.012
Abstract:
The characteristics of species composition,quantitative distribution and seasonal variation of zooplankton in the Qinzhou Bay were investigated in flood season in 2011(July) and dry season in 2012(March). Species quantity of zooplankton were 27 and 44 with dominant species(Y >0.02) of 3 and 4 in flood and dry seasons,respectively. The dominant species were Acartia (Odontacartia) pacifica,Pleurobrachia globosa and Lucifer intermedius in flood season,while Calanus sinicus,Pleurobrachia globosa,Oikopleura (Vexillaria) dioica and Centropages tenuiremis in dry season. The abundance of zooplankton ranged from 4.01-133.64 ind/m3 with an average of 50.9 ind/m3 in flood season,while 1.2-1 725.0 ind/m3 with an average of 272.2 ind/m3 in dry season. However,biomass of zooplankton which included fish eggs and larvae ranged from 1.7-179.2 mg/m3 with an average of 44.0 mg/m3 in flood season,while 3.1-3 530.0 mg/m3 with an average of 474.9 mg/m3 in dry season. Qinzhou Bay was in an characterized,rapid change estuary environment,its marine system,which affected by rivers runoff,Beibu Gulf coastal waters etc.,was complex and it's community structure of zooplankton presented complex diversity. Estuarine group [such as Acartia (Odontacartia) pacifica] and warm water nearshore group(such as Tortanus forcipatus) were the main ecological groups of zooplankton community structure. Both in the species number and abundance of zooplankton,Copepoda were the predominant species. Temporal and spatial distribution of species number,abundance and biomass of zooplankton were higher in outer bay than that in inner bay,as well as higher in dry season than that in flood season. The seasonal variation and spatial distribution characteristics of zooplankton in the Qinzhou Bay mainly had a close relationship with the phytoplankton biomass,shellfish culture,stability of the environment and human disturbance.
The characteristics of species composition,quantitative distribution and seasonal variation of zooplankton in the Qinzhou Bay were investigated in flood season in 2011(July) and dry season in 2012(March). Species quantity of zooplankton were 27 and 44 with dominant species(Y >0.02) of 3 and 4 in flood and dry seasons,respectively. The dominant species were Acartia (Odontacartia) pacifica,Pleurobrachia globosa and Lucifer intermedius in flood season,while Calanus sinicus,Pleurobrachia globosa,Oikopleura (Vexillaria) dioica and Centropages tenuiremis in dry season. The abundance of zooplankton ranged from 4.01-133.64 ind/m3 with an average of 50.9 ind/m3 in flood season,while 1.2-1 725.0 ind/m3 with an average of 272.2 ind/m3 in dry season. However,biomass of zooplankton which included fish eggs and larvae ranged from 1.7-179.2 mg/m3 with an average of 44.0 mg/m3 in flood season,while 3.1-3 530.0 mg/m3 with an average of 474.9 mg/m3 in dry season. Qinzhou Bay was in an characterized,rapid change estuary environment,its marine system,which affected by rivers runoff,Beibu Gulf coastal waters etc.,was complex and it's community structure of zooplankton presented complex diversity. Estuarine group [such as Acartia (Odontacartia) pacifica] and warm water nearshore group(such as Tortanus forcipatus) were the main ecological groups of zooplankton community structure. Both in the species number and abundance of zooplankton,Copepoda were the predominant species. Temporal and spatial distribution of species number,abundance and biomass of zooplankton were higher in outer bay than that in inner bay,as well as higher in dry season than that in flood season. The seasonal variation and spatial distribution characteristics of zooplankton in the Qinzhou Bay mainly had a close relationship with the phytoplankton biomass,shellfish culture,stability of the environment and human disturbance.
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