Most cited articles
2011, 20(2):260-269.
Abstract:
Habitat suitability index (HSI) has been widely used in fishery resources exploitation, management, assessment and protection since it was found in the early 1980s, and it has become one of the most important tools in fishery science research. In this article, outlining the studies in the world, the theory and methods of HSI, and the advance applications and exist problems have been summarized. Some advice should be considered sufficiently in the application of HSI, i.e., (1) study on target species’ life history and biological characteristics and its habitats; (2) suitable environment factors should be selected according to different growth stages; (3) research on spatialtempral scales of data and rule set on data; (4) selecting logical weights upon different factors based on literature and expert knowledge; (5) selecting preparatory HSI models be propitious to the various goals, such as protection area, fishing ground and biomass evaluation; (6) selecting suitable HSI models by comparison of models and related analysis; (7) modifying models using insitu or recent data in order to improve precision of model.
Habitat suitability index (HSI) has been widely used in fishery resources exploitation, management, assessment and protection since it was found in the early 1980s, and it has become one of the most important tools in fishery science research. In this article, outlining the studies in the world, the theory and methods of HSI, and the advance applications and exist problems have been summarized. Some advice should be considered sufficiently in the application of HSI, i.e., (1) study on target species’ life history and biological characteristics and its habitats; (2) suitable environment factors should be selected according to different growth stages; (3) research on spatialtempral scales of data and rule set on data; (4) selecting logical weights upon different factors based on literature and expert knowledge; (5) selecting preparatory HSI models be propitious to the various goals, such as protection area, fishing ground and biomass evaluation; (6) selecting suitable HSI models by comparison of models and related analysis; (7) modifying models using insitu or recent data in order to improve precision of model.
2012, 21(3):431-438.
Abstract:
Illex argentinus is an important target species for Chinese squid jigging fleets in the southwest Atlantic,and the accurate forecasting of fishing ground can provide better scientific guidance for fishing activities. In this study, according to the Chinese squid fishing production data during the main fishing season (January to May) from 2000 to 2005, combined with sea surface temperature (SST) and chl.a accordingly, the percentage of fishing times and daily catch (CPUE) will be considered as the suitability index (SI). Using arithmetic mean model (AM) to establish the integrated habitat suitability index (HSI) based on SST and chl.a from 2000 to 2004, and the fishing and environmental data were used to test the established HSI model from January to May in 2005. The results indicated that AM model is fitted well. According to the data from January to May in 2005, we found that the main fishing ground is distributed in the waters with HSI more than 0.6 from the AM HSI model, and its percentage of fishing times reached more than 76 percent and its average CPUE were above 7.6 t/d. The results showed that the AM HSI model based on SST and chl.a can better predict the fishing grounds of squid in the southwest Atlantic and the accuracy rate of forecasting fishing ground reaches more than 70%.
Illex argentinus is an important target species for Chinese squid jigging fleets in the southwest Atlantic,and the accurate forecasting of fishing ground can provide better scientific guidance for fishing activities. In this study, according to the Chinese squid fishing production data during the main fishing season (January to May) from 2000 to 2005, combined with sea surface temperature (SST) and chl.a accordingly, the percentage of fishing times and daily catch (CPUE) will be considered as the suitability index (SI). Using arithmetic mean model (AM) to establish the integrated habitat suitability index (HSI) based on SST and chl.a from 2000 to 2004, and the fishing and environmental data were used to test the established HSI model from January to May in 2005. The results indicated that AM model is fitted well. According to the data from January to May in 2005, we found that the main fishing ground is distributed in the waters with HSI more than 0.6 from the AM HSI model, and its percentage of fishing times reached more than 76 percent and its average CPUE were above 7.6 t/d. The results showed that the AM HSI model based on SST and chl.a can better predict the fishing grounds of squid in the southwest Atlantic and the accuracy rate of forecasting fishing ground reaches more than 70%.
WANG Wei
,
CHEN Jun
,
LIU Huang
,
HE Ya-ping (.Fishery Machinery
,
Instrument Reserch Institute of Chinece Academy of Fishery Scinces
,
Shanghai
,
China
,
.Key Laboratory of Fishery Equipment
,
Engineering
,
Ministry of Agriculture
,
China)
2010(1).
Abstract:
Aquaculture water purification technology is one part of modern aquaculture engineering.Taking water body as object of study,its aim is to solve the problems of aquatic products safety,fish diseases and resource environment,by using controllable artificial measures,and physical,chemical and biological methods to improve the aquaculture water environment.The current aquaculture water purification technology in China mainly includes physical filtration,ultraviolet & ozone disinfection,water aeration,artificia...
Aquaculture water purification technology is one part of modern aquaculture engineering.Taking water body as object of study,its aim is to solve the problems of aquatic products safety,fish diseases and resource environment,by using controllable artificial measures,and physical,chemical and biological methods to improve the aquaculture water environment.The current aquaculture water purification technology in China mainly includes physical filtration,ultraviolet & ozone disinfection,water aeration,artificia...
ZHAO Jing
,
ZHANG Shou-yu
,
XU Min(Marine Ecosystem & Environmental Laboratory
,
College of Marine Sciences
,
Shanghai Ocean University
,
Shanghai
,
China)
2010(1).
Abstract:
The kelp bed is a typical offshore ecosystem,with especial ecosystem structure and abundance aquicolous resources,which made it have a complex energy structure and obvious character.By using Ecopath with Ecosim(EWE) software,a mass-balanced ecopath model of the kelp bed ecosystem in Gouqi was constructed.Through the analysis of the trophic level,energy flowing,and the ecosystem characters etc.also combining the function of kelp bed,the state of the kelp bed was estimated,and the causes were discussed here.T...
The kelp bed is a typical offshore ecosystem,with especial ecosystem structure and abundance aquicolous resources,which made it have a complex energy structure and obvious character.By using Ecopath with Ecosim(EWE) software,a mass-balanced ecopath model of the kelp bed ecosystem in Gouqi was constructed.Through the analysis of the trophic level,energy flowing,and the ecosystem characters etc.also combining the function of kelp bed,the state of the kelp bed was estimated,and the causes were discussed here.T...
2012, 21(5):841-847.
Abstract:
Retrospective problem (RR) was defined as systematic biases in successive estimations of fishery parameters (typically stock biomass and fishing mortality) with additional years of data added in stock assessment. RP arising in many fishery stock assessments can potentially result in large uncertainty in fish stock biomass estimates, which will lead to over exploit or under exploit fish populations. RP is one of hot and hard topics in fishery stock assessment at present. The MOHN ρ was used mainly as the metric of RP and the cause of RP was reduced to errors in data or in assumption of models or both. At present, there were diverse methods for diagnoses of RP, but these methods were generally valid only in some specific case. The researchers working on fisheries stock assessment provided some methods to fix or avoid RP according to their specific study, but there was still a lack of general methods or means to correct or avoid RP. If RP occurred in a stock assessment, there must be some errors in data or assumption of the model. Therefore, Retrospective analysis was effective means to assess the quality of the data and check the consistency of assumption between data and the model.
Retrospective problem (RR) was defined as systematic biases in successive estimations of fishery parameters (typically stock biomass and fishing mortality) with additional years of data added in stock assessment. RP arising in many fishery stock assessments can potentially result in large uncertainty in fish stock biomass estimates, which will lead to over exploit or under exploit fish populations. RP is one of hot and hard topics in fishery stock assessment at present. The MOHN ρ was used mainly as the metric of RP and the cause of RP was reduced to errors in data or in assumption of models or both. At present, there were diverse methods for diagnoses of RP, but these methods were generally valid only in some specific case. The researchers working on fisheries stock assessment provided some methods to fix or avoid RP according to their specific study, but there was still a lack of general methods or means to correct or avoid RP. If RP occurred in a stock assessment, there must be some errors in data or assumption of the model. Therefore, Retrospective analysis was effective means to assess the quality of the data and check the consistency of assumption between data and the model.
2017, 26(3):450-457.
DOI: 10.12024/jsou.20160501781
Abstract:
Squid is one of the important economic species in the northwestern Pacific. Using Catch per Unit Effort and V% as the target of central fishing ground and adopting BP artificial neural network, we forecast fishing ground in the northwest Pacific Ocean. The study was based on the data of squid fishing and relevant marine environment factors, including longitude, latitude, SST and SSHA from July to November from 1995 to 2001.The input factor is marine environment factor, the output factors are CPUE and V% and 4-3-1 and 4-2-1 model total 4 kinds models were used to compare which is the best suitable model for fishery forecast. The minimum fitting residual of model is the best one. Result shows that 4-3-1 is the best suitable model for each month, but the best suitable model for July and August is 4-3-1 with output V% and best suitable model for September, October and November is 4-3-1 with output CPUE, the minimum overall average error is 4-3-1 model output V%. Research suggests that there are differences as a center of fishery forecast targets by CPUE and V%, and the 4-3-1 model output V% can be used as forecasting model of squid fishing ground.
Squid is one of the important economic species in the northwestern Pacific. Using Catch per Unit Effort and V% as the target of central fishing ground and adopting BP artificial neural network, we forecast fishing ground in the northwest Pacific Ocean. The study was based on the data of squid fishing and relevant marine environment factors, including longitude, latitude, SST and SSHA from July to November from 1995 to 2001.The input factor is marine environment factor, the output factors are CPUE and V% and 4-3-1 and 4-2-1 model total 4 kinds models were used to compare which is the best suitable model for fishery forecast. The minimum fitting residual of model is the best one. Result shows that 4-3-1 is the best suitable model for each month, but the best suitable model for July and August is 4-3-1 with output V% and best suitable model for September, October and November is 4-3-1 with output CPUE, the minimum overall average error is 4-3-1 model output V%. Research suggests that there are differences as a center of fishery forecast targets by CPUE and V%, and the 4-3-1 model output V% can be used as forecasting model of squid fishing ground.
CHENG Fang
,
LING Qu-fei
,
XU Hai-jun
,
LIN Jian-hua
,
WU Lin-kun
,
JIA Wen-fang (.School of Life Sciences
,
Soochow University
,
Suzhou
,
China
,
.Taihu Lake Fisheries Administration Committee of Jiangsu Province
,
Suzhou
,
China)
2010(1).
Abstract:
The analysis samples of water chemistry and aquatic biology were collected quarterly in Taihu Lake from November 2007 to August 2008.We evaluate the actual condition of water quality and the main pollution sources of Taihu Lake by ways of water pollution index and comprehensive analysis of eutrophication.Evaluation of water pollution index analysis revealed that the main pollutants in Taihu Lake were nitrogen(N),phosphorus(P) and organic oxygen consumption(COD Mn).Total phosphorus(TP) shared the largest pol...
The analysis samples of water chemistry and aquatic biology were collected quarterly in Taihu Lake from November 2007 to August 2008.We evaluate the actual condition of water quality and the main pollution sources of Taihu Lake by ways of water pollution index and comprehensive analysis of eutrophication.Evaluation of water pollution index analysis revealed that the main pollutants in Taihu Lake were nitrogen(N),phosphorus(P) and organic oxygen consumption(COD Mn).Total phosphorus(TP) shared the largest pol...
2011, 20(1):102-107.
Abstract:
Based on the catch and fishing effort data from small scale traditional light seining fisheries of Zhejiang Province and abundance data estimated by Fisheries Agency of Japan, the influence of the sea surface temperature (SST) from East China Sea and sea surface temperature anomaly (SSTA) from Niňo 3.4 area on the stock size of chub mackerel in East China Sea was analyzed. The results showed that there were significant positive relation (P<0.05) between SST and CPUE derived from small scale traditional light seining fisheries of Zhejiang Province and significant negative relation (P<0.05) between SST and abundance from Japan. The averaged SSTA of Niňo 3.4 from January to March can be considered as an index which roughly reflected abundance levels. When the averaged SSTA was negative, there was a great chance in lean year for chub mackerel stock, and vice versa. The opposite relationships between SST and abundance from different areas may be attributed to the influence of SST on migration of chub mackerel. La Niňa event would have a negative impact on the resource in the whole East China Sea, but the reason needs to be investigated in the future. The results indicated that the temporal and spatial dynamics of the stock should be included in the stock assessment for chub mackerel.
Based on the catch and fishing effort data from small scale traditional light seining fisheries of Zhejiang Province and abundance data estimated by Fisheries Agency of Japan, the influence of the sea surface temperature (SST) from East China Sea and sea surface temperature anomaly (SSTA) from Niňo 3.4 area on the stock size of chub mackerel in East China Sea was analyzed. The results showed that there were significant positive relation (P<0.05) between SST and CPUE derived from small scale traditional light seining fisheries of Zhejiang Province and significant negative relation (P<0.05) between SST and abundance from Japan. The averaged SSTA of Niňo 3.4 from January to March can be considered as an index which roughly reflected abundance levels. When the averaged SSTA was negative, there was a great chance in lean year for chub mackerel stock, and vice versa. The opposite relationships between SST and abundance from different areas may be attributed to the influence of SST on migration of chub mackerel. La Niňa event would have a negative impact on the resource in the whole East China Sea, but the reason needs to be investigated in the future. The results indicated that the temporal and spatial dynamics of the stock should be included in the stock assessment for chub mackerel.
2018, 27(4):531-542.
DOI: 10.12024/jsou.20171002156
Abstract:
In order to study the effect of composite vertical subsurface flow constructed wetlands on the removal of heavy metals in pond aquaculture water, the correlation between different plant roots and their substrates near roots on heavy metal enrichment effect, different environmental factors and heavy metal enrichment rate were analyzed by measuring water quality index and heavy metal. The results showed that the removal efficiencies of Pb and Cu in constructed wetlands were 77.20% and 41.70%, respectively. Compared with other types of wetlands, the composite vertical subsurface flow constructed wetlands had some advantages for the removal of Pb and Cu; the As was released in wetland with an average release rate of 8.40%. The roots of Polygonum hydropiper and Thalia dealbata Fraser have enrichment effect on Cr, As, Pb and Cu, and the roots of Pontederia cordata L. have only enrichment of Cr and As. The substrates near the roots of Polygonum hydropiper, Pontederia cordata L., and Thalia dealbata Fraser have a good enrichment effect on chromium, and among them, the maximum rate of the concentration of Pontederia cordata L. to chromium is 0.987mg/(kg·d). The enrichment rate of Pb and Cu in Polygonum hydropiper root was negatively correlated with temperature and the enrichment rate of Cr and Cu was negatively correlated with pH; the enrichment rate of Cr and As in Pontederia cordata L. root was negatively correlated with temperature; the enrichment rate of Pb in Thalia dealbata Fraser root was negatively correlated with temperature and pH, the enrichment rate of Cu was negatively correlated with temperature. The results of this study provide a theoretical basis and reference for the application of composite vertical subsurface flow constructed wetlands and the selection of wetland plants from the perspective of heavy metal removal.
In order to study the effect of composite vertical subsurface flow constructed wetlands on the removal of heavy metals in pond aquaculture water, the correlation between different plant roots and their substrates near roots on heavy metal enrichment effect, different environmental factors and heavy metal enrichment rate were analyzed by measuring water quality index and heavy metal. The results showed that the removal efficiencies of Pb and Cu in constructed wetlands were 77.20% and 41.70%, respectively. Compared with other types of wetlands, the composite vertical subsurface flow constructed wetlands had some advantages for the removal of Pb and Cu; the As was released in wetland with an average release rate of 8.40%. The roots of Polygonum hydropiper and Thalia dealbata Fraser have enrichment effect on Cr, As, Pb and Cu, and the roots of Pontederia cordata L. have only enrichment of Cr and As. The substrates near the roots of Polygonum hydropiper, Pontederia cordata L., and Thalia dealbata Fraser have a good enrichment effect on chromium, and among them, the maximum rate of the concentration of Pontederia cordata L. to chromium is 0.987mg/(kg·d). The enrichment rate of Pb and Cu in Polygonum hydropiper root was negatively correlated with temperature and the enrichment rate of Cr and Cu was negatively correlated with pH; the enrichment rate of Cr and As in Pontederia cordata L. root was negatively correlated with temperature; the enrichment rate of Pb in Thalia dealbata Fraser root was negatively correlated with temperature and pH, the enrichment rate of Cu was negatively correlated with temperature. The results of this study provide a theoretical basis and reference for the application of composite vertical subsurface flow constructed wetlands and the selection of wetland plants from the perspective of heavy metal removal.
CAO Jie
,
CHEN Xin-jun
,
,
LIU Bi-lin
,
TIAN Si-quan
,
QIAN Wei-guo
,
(.College of Marine Sciences
,
Shanghai Ocean University
,
Shanghai
,
China
,
.Key Laboratory of Shanghai Education Commission for Oceanic Fisheries Resources Exploitation
,
.Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources
,
Ministry of Education
,
China)
2010(2).
Abstract:
Over the past decades,with the decline of economic finfish stocks around the world,the short-life cycle squid has become one of important fishing targets and its total catches keep on increasing.Becasue the short-life cycle squid is sensitive responding to environmental changes with great abundence fluctuations,which sometimes reduces the recruitment to the stocks,the assessment and management do not work well based on traditional population dynamic models.In this paper,we review the development of methods ...
Over the past decades,with the decline of economic finfish stocks around the world,the short-life cycle squid has become one of important fishing targets and its total catches keep on increasing.Becasue the short-life cycle squid is sensitive responding to environmental changes with great abundence fluctuations,which sometimes reduces the recruitment to the stocks,the assessment and management do not work well based on traditional population dynamic models.In this paper,we review the development of methods ...
2011, 20(4):534-540.
Abstract:
To investigate the effect of different doses of compound Chinese herbal immunostimulant in feed on the growth and immune function of grass carp, which was fed with the diets including the compound Chinese herbal immunostimulant, a kind of mixture of five Chinese herbs is proportionally composed of Astragalus membranaceus, Allium sativum, Dendranthema morifolium，Frutellaria crataegi and Isatis indigotica. Grass carp individuals, the average weight of which was (27.84?1.57) g, were fed with 1%, 2%, 4% and 8% compound Chinese herbal immunostimulant in feed for 30 days, respectively. Results showed that weight gain rate（WGR）and specific growth rate（SGR）in Groups 1, 2 and 3 (especially Group 3) increased significantly compared with those of the control group(P<0.05), and phagocytic activities of phagocytes of all test groups increased significantly (P<0.05), while serum lysozyme（LSZ）activities and serum superoxide dismutase (SOD) activities of all test groups increased very significantly (P<0.01). Relative percentage survivals of test groups were very significantly higher than that of the control group (P<0.01), when the grass carps were injected with Aeromonas hydrophila, and the highest one reached 70.28%?6.26% in Group 3. Therefore, 4% Chinese herbal immunostimulant in feed was the fittest for the growth and immunity increment, and resistance of grass carp against the bacterial pathogen, Aeromonas hydrophila.
To investigate the effect of different doses of compound Chinese herbal immunostimulant in feed on the growth and immune function of grass carp, which was fed with the diets including the compound Chinese herbal immunostimulant, a kind of mixture of five Chinese herbs is proportionally composed of Astragalus membranaceus, Allium sativum, Dendranthema morifolium，Frutellaria crataegi and Isatis indigotica. Grass carp individuals, the average weight of which was (27.84?1.57) g, were fed with 1%, 2%, 4% and 8% compound Chinese herbal immunostimulant in feed for 30 days, respectively. Results showed that weight gain rate（WGR）and specific growth rate（SGR）in Groups 1, 2 and 3 (especially Group 3) increased significantly compared with those of the control group(P<0.05), and phagocytic activities of phagocytes of all test groups increased significantly (P<0.05), while serum lysozyme（LSZ）activities and serum superoxide dismutase (SOD) activities of all test groups increased very significantly (P<0.01). Relative percentage survivals of test groups were very significantly higher than that of the control group (P<0.01), when the grass carps were injected with Aeromonas hydrophila, and the highest one reached 70.28%?6.26% in Group 3. Therefore, 4% Chinese herbal immunostimulant in feed was the fittest for the growth and immunity increment, and resistance of grass carp against the bacterial pathogen, Aeromonas hydrophila.
2011, 20(5):688-696.
Abstract:
From August 2009 to August 2010, larval and juvenile fishes were monthly collected by a seine net(1m×4m，1 mm meshaperture) in the surf zones of south branch of Yangtze River estuary and north coast of Hangzhou Bay. 267 hauls were conducted in the Yangtze River estuary, and a total of 11 066 catches belonging to 43 species from 23 families were collected, the most dominant species was Coilia nasus which comprised 64.44% of the total catches.195 hauls were conducted in Hangzhou Bay, a total of 3 841 catches belonging to 62 species from 23 families were collected, Acentrogobius pflaumii and Eleutheronema rhadinum comprised 61.73% of the total catches. The differences of geography and aquatic environment between two areas affected composition of fish assemblage, while 26 mutual species occurred, the dissimilarity index still rose to 0.927. Developmental stage of fish larvae and juveniles also showed some differences, postflexion and juvenile fish dominated the total catches in Hangzhou Bay, whereas the variation in Yangtze River estuary was not in evidence.Community diversity of Hangzhou Bay is higher than that of the Yangtze River estuary, and the Margalef index, ShannonWierner index and Pielou eveness index were all higher. Kdominance curves revealed that the species richness was higher in Hangzhou Bay.
From August 2009 to August 2010, larval and juvenile fishes were monthly collected by a seine net(1m×4m，1 mm meshaperture) in the surf zones of south branch of Yangtze River estuary and north coast of Hangzhou Bay. 267 hauls were conducted in the Yangtze River estuary, and a total of 11 066 catches belonging to 43 species from 23 families were collected, the most dominant species was Coilia nasus which comprised 64.44% of the total catches.195 hauls were conducted in Hangzhou Bay, a total of 3 841 catches belonging to 62 species from 23 families were collected, Acentrogobius pflaumii and Eleutheronema rhadinum comprised 61.73% of the total catches. The differences of geography and aquatic environment between two areas affected composition of fish assemblage, while 26 mutual species occurred, the dissimilarity index still rose to 0.927. Developmental stage of fish larvae and juveniles also showed some differences, postflexion and juvenile fish dominated the total catches in Hangzhou Bay, whereas the variation in Yangtze River estuary was not in evidence.Community diversity of Hangzhou Bay is higher than that of the Yangtze River estuary, and the Margalef index, ShannonWierner index and Pielou eveness index were all higher. Kdominance curves revealed that the species richness was higher in Hangzhou Bay.
2013, 22(2):219-224.
Abstract:
112 Aeromonas strains were isolated from various aquatic animals at different time in Guangdong province. Kirby Bauer disc diffusion method was used to detect the resistance of 112 strains against 20 commonly used antimicrobial agents. Resistance rates were analyzed by WHONET 5.6 software. The overall resistance rates were highest for ampicillin (85.7%) and cephalothin (79.5%) followed by rifampicin (57.1%)，amoxicillin/clavulanic acid (51.8%)，streptomycin (49.1%)，sulfonamides (31.2%)，cefoxitin（28.6%），tetracycline (28.6%) and trimethoprim/sulfamethoxazole (21.4%). Aeromonas isolates were suseptible to most of antimicrobial agents and a low incidence (<10%) of resistance to imipenem (0.9%)，nitrofurantoin (0.9%), ceftriaxone (1.8%)， cefotaxime (2.7%) and amikacin (3.6%) were observed. Although 46.6% of isolates displayed nalidixic acid resistance，majority of isolates were very susceptible to other kinds of fluroquinolones. Compared with the resistance rates of different antimicrobial agents from different origins of aquatic animals, fluroquinolones and cephalosporins resistance was more prevalent in strains from reptiles, amphibians and ornamental fishes than those from farm fishes and shrimps. Our results showed that antimicrobial resistant Aeromonas were widespread in the aquaculture in Guangdong and show various resistant rates to different antimircrobial agents. There is a need to build a national surveillance system of antimicrobial resistance in aquaculture.
112 Aeromonas strains were isolated from various aquatic animals at different time in Guangdong province. Kirby Bauer disc diffusion method was used to detect the resistance of 112 strains against 20 commonly used antimicrobial agents. Resistance rates were analyzed by WHONET 5.6 software. The overall resistance rates were highest for ampicillin (85.7%) and cephalothin (79.5%) followed by rifampicin (57.1%)，amoxicillin/clavulanic acid (51.8%)，streptomycin (49.1%)，sulfonamides (31.2%)，cefoxitin（28.6%），tetracycline (28.6%) and trimethoprim/sulfamethoxazole (21.4%). Aeromonas isolates were suseptible to most of antimicrobial agents and a low incidence (<10%) of resistance to imipenem (0.9%)，nitrofurantoin (0.9%), ceftriaxone (1.8%)， cefotaxime (2.7%) and amikacin (3.6%) were observed. Although 46.6% of isolates displayed nalidixic acid resistance，majority of isolates were very susceptible to other kinds of fluroquinolones. Compared with the resistance rates of different antimicrobial agents from different origins of aquatic animals, fluroquinolones and cephalosporins resistance was more prevalent in strains from reptiles, amphibians and ornamental fishes than those from farm fishes and shrimps. Our results showed that antimicrobial resistant Aeromonas were widespread in the aquaculture in Guangdong and show various resistant rates to different antimircrobial agents. There is a need to build a national surveillance system of antimicrobial resistance in aquaculture.
2013, 22(5):734-743.
Abstract:
The most of fish species have the schooling behavior, due to the different causes and mechanism of schooling, which are presented by varied definitions of different words, such as shoal, cluster or aggregation, even swam or flock, etc. This article describes and analyses the definitions and classification based on their characteristics, and recommends the word “schooling” is mostly reflecting the phenomenon of fish migration in group. The way to explore the mechanism of schooling, the factors having impact on their behavior, and the methods used in the varied studies are reviewed. And the characteristics of the structure of fish school, sub groups, the phenomena of self organization, etc. are summarized. It is recommended that the mathematics model and simulation technique are effective methods to explore the mechanism of fish self organization phenomenon. This is a way to understand nature by “linkage by phenomena only”, based on observation data, experience and phenomena observed, building mathematics model for predicating and forecasting the fish behavior and schooling structure, and the results of simulation will again be compared with the actual observation records. It might speculate or determine the dominant factors affecting the schooling phenomenon or mechanism. Meanwhile, computer technology provides support for the creation of complex models using simulation technology as an effective tool to study fish schooling behavior in recent years.
The most of fish species have the schooling behavior, due to the different causes and mechanism of schooling, which are presented by varied definitions of different words, such as shoal, cluster or aggregation, even swam or flock, etc. This article describes and analyses the definitions and classification based on their characteristics, and recommends the word “schooling” is mostly reflecting the phenomenon of fish migration in group. The way to explore the mechanism of schooling, the factors having impact on their behavior, and the methods used in the varied studies are reviewed. And the characteristics of the structure of fish school, sub groups, the phenomena of self organization, etc. are summarized. It is recommended that the mathematics model and simulation technique are effective methods to explore the mechanism of fish self organization phenomenon. This is a way to understand nature by “linkage by phenomena only”, based on observation data, experience and phenomena observed, building mathematics model for predicating and forecasting the fish behavior and schooling structure, and the results of simulation will again be compared with the actual observation records. It might speculate or determine the dominant factors affecting the schooling phenomenon or mechanism. Meanwhile, computer technology provides support for the creation of complex models using simulation technology as an effective tool to study fish schooling behavior in recent years.
2013, 22(5).
Abstract:
The most of fish species have the schooling behavior, due to the different causes and mechanism of schooling, which presented by varied definition of different words, such as shoal, cluster or aggregation even swam or flock etc. This article describes and analyses the definitions and classification based on their characteristics, and recommend the word “schooling” is mostly reflecting the phenomenon of fish migration in group. The way to explore the mechanism of schooling, the factors having impact on their behavior, and the methods used in the varied studies ?are reviewed. And the characteristic of the structure of fish school, sub-groups, the phenomena of self-organization etc are summarized. It is recommended that the mathematics model and simulation technical is an effective method to explore the mechanism of fish self-organization phenomenon. This is a way to understand nature by "linkage by phenomena only", based on observation data, experience and phenomena observed, building mathematics model for predicating and forecasting the fish behavior and schooling structure, the results of simulation will again be compared with the actual observation records, it might speculate or determine the dominant factors which effecting the schooling phenomenon or mechanism. Meanwhile, Computer technology provides support for the creation of complex models using simulation technology as an effective tool to study fish schooling behavior in recent years.
The most of fish species have the schooling behavior, due to the different causes and mechanism of schooling, which presented by varied definition of different words, such as shoal, cluster or aggregation even swam or flock etc. This article describes and analyses the definitions and classification based on their characteristics, and recommend the word “schooling” is mostly reflecting the phenomenon of fish migration in group. The way to explore the mechanism of schooling, the factors having impact on their behavior, and the methods used in the varied studies ?are reviewed. And the characteristic of the structure of fish school, sub-groups, the phenomena of self-organization etc are summarized. It is recommended that the mathematics model and simulation technical is an effective method to explore the mechanism of fish self-organization phenomenon. This is a way to understand nature by "linkage by phenomena only", based on observation data, experience and phenomena observed, building mathematics model for predicating and forecasting the fish behavior and schooling structure, the results of simulation will again be compared with the actual observation records, it might speculate or determine the dominant factors which effecting the schooling phenomenon or mechanism. Meanwhile, Computer technology provides support for the creation of complex models using simulation technology as an effective tool to study fish schooling behavior in recent years.
16 Causal analysis and distribution of eutrophication index in the Yueqing Bay in spring-summer of 2007
2010(1).
Abstract:
依据2007年4月和8月在乐清湾28°05′~28°35′N、121°00′~121°20′E海域进行海洋综合调查,对乐清湾营养水平指标(E)和有机污染指数(A)值的空间分布特征进行研究,讨论这些分布特征与营养盐、潮流场、污染源和叶绿素之间的联系。结果表明,乐清湾E值和A值分布趋势基本相同,都是由内湾向外湾数量逐渐减少。相关分析表明:溶解态磷酸盐(D IP)和溶解态无机氮(D IN)与E值、A值之间都有密切的相关关系(P=0.000 0),因而是污染乐清湾水体的主要因子。营养盐分布特征的形成,主要由乐清湾地形、潮流、污染源和叶绿素特征决定的,在乐清湾海域,沿外湾东部的海槽是乐清湾中湾和外湾涨落潮的主要路径,形成外湾较低的D IP和D IN值。而养殖污染带来总氮和总磷的数量分别接近和超过50%,因而是乐清湾水体变劣的重要外源性污染物,其次是生活污水和化肥的输入。夏季,浮游植物对营养盐大量利用,有效地减少了乐清湾营养盐的含量,进一步导致水体营养水平指标(E)和有机污染指数(A)值的降低。4月乐清湾水体处于富营养化、严重污染和亚健康状态。8月,内湾和中湾属于污染海域,处于亚健康状态。外湾大部分属于较清洁海域,处于健...
依据2007年4月和8月在乐清湾28°05′~28°35′N、121°00′~121°20′E海域进行海洋综合调查,对乐清湾营养水平指标(E)和有机污染指数(A)值的空间分布特征进行研究,讨论这些分布特征与营养盐、潮流场、污染源和叶绿素之间的联系。结果表明,乐清湾E值和A值分布趋势基本相同,都是由内湾向外湾数量逐渐减少。相关分析表明:溶解态磷酸盐(D IP)和溶解态无机氮(D IN)与E值、A值之间都有密切的相关关系(P=0.000 0),因而是污染乐清湾水体的主要因子。营养盐分布特征的形成,主要由乐清湾地形、潮流、污染源和叶绿素特征决定的,在乐清湾海域,沿外湾东部的海槽是乐清湾中湾和外湾涨落潮的主要路径,形成外湾较低的D IP和D IN值。而养殖污染带来总氮和总磷的数量分别接近和超过50%,因而是乐清湾水体变劣的重要外源性污染物,其次是生活污水和化肥的输入。夏季,浮游植物对营养盐大量利用,有效地减少了乐清湾营养盐的含量,进一步导致水体营养水平指标(E)和有机污染指数(A)值的降低。4月乐清湾水体处于富营养化、严重污染和亚健康状态。8月,内湾和中湾属于污染海域,处于亚健康状态。外湾大部分属于较清洁海域,处于健...
2011, 20(6):808-813.
Abstract:
The effects of different dissolved oxygen (DO) concentrations, including severe hypoxia(0.2, 1.0, 2.0 mg/L), hypoxia(3.0, 5.0 mg/L), normoxia(normal aeration as control, about 7.0 mg/L) and hyperoxia(11.0, 14.0 mg/L), on nucleus anomaly in erythrocytes, superoxide dismutase(SOD), catalase(CAT) activities in serum and malondialdehyde(MDA) concentration in liver were studied in juvenile turbot Scophthalmus maximus. Fish mortality was only observed in the 0.2, 1.0 and 2.0 mg/L groups, in which all fish died in 2 h, 24 h and 48 h, respectively. The effects of DO on nucleus anomalies were shown with obvious timecumulative effects and dosecumulative effects in the 28day experiment. The micronuclei were first observed in the 5.0, 14.0 mg/L and control groups on day 28. They were still found in hyperoxia and control groups after recovery for 14 days. The SOD activities in different groups showed significant difference at each sampling time (P<0.05). The difference in CAT activities among experiment groups was significant only after 7day exposure (P<0.05). The MDA concentration increased with the increasing concentration at 2 h. The MDA concentration in hypoxia and hyperoxia groups decreased with time duration. After 14day recovery, the MDA concentration in hypoxia groups was significantly higher compared with those in control groups (P<0.05). Additionally, the oxidative stresses were also found in control groups. No obvious changes on the total nucleus anomalies and other antioxidative index were found in 5.0 mg/L groups.
The effects of different dissolved oxygen (DO) concentrations, including severe hypoxia(0.2, 1.0, 2.0 mg/L), hypoxia(3.0, 5.0 mg/L), normoxia(normal aeration as control, about 7.0 mg/L) and hyperoxia(11.0, 14.0 mg/L), on nucleus anomaly in erythrocytes, superoxide dismutase(SOD), catalase(CAT) activities in serum and malondialdehyde(MDA) concentration in liver were studied in juvenile turbot Scophthalmus maximus. Fish mortality was only observed in the 0.2, 1.0 and 2.0 mg/L groups, in which all fish died in 2 h, 24 h and 48 h, respectively. The effects of DO on nucleus anomalies were shown with obvious timecumulative effects and dosecumulative effects in the 28day experiment. The micronuclei were first observed in the 5.0, 14.0 mg/L and control groups on day 28. They were still found in hyperoxia and control groups after recovery for 14 days. The SOD activities in different groups showed significant difference at each sampling time (P<0.05). The difference in CAT activities among experiment groups was significant only after 7day exposure (P<0.05). The MDA concentration increased with the increasing concentration at 2 h. The MDA concentration in hypoxia and hyperoxia groups decreased with time duration. After 14day recovery, the MDA concentration in hypoxia groups was significantly higher compared with those in control groups (P<0.05). Additionally, the oxidative stresses were also found in control groups. No obvious changes on the total nucleus anomalies and other antioxidative index were found in 5.0 mg/L groups.
2012, 21(5):831-840.
Abstract:
The oceanic Ommastrephidae is an important cephalopod resource. The main species which have been exploited at the large scale commercial development included 〖WTBX〗Todarodes pacificus, Illex argentinus, Dosidicus gigas, Nototodarus sloani and Symplectoteuthis oualaniensis. According to the data statistics during 1992 to 2010, the Ommastrephidae production accounted for 51.15%-62.19% of cephalopods in the world, with an average of 55.40%. In this paper, the current exploitation and resources conditions of Todarodes pacificus, Illex argentinus, Dosidicus gigas and other squids are described in details. Meanwhile, according to the biological characteristics of short life cycle and fast growth, four major scientific issues which are to be resolved have been put forward. The four scientific issues are: (1) a completely comprehensive understanding of the ecological status and role of Ommastrephidae; (2) fully mastering the effect of environment including global climate change on the recruitment of Ommastrephidae; (3) further study of assessment model for Ommastrephidae based on the short life cycle; and (4) developing the ecosystem based resource management approaches for Ommastrephidae.
The oceanic Ommastrephidae is an important cephalopod resource. The main species which have been exploited at the large scale commercial development included 〖WTBX〗Todarodes pacificus, Illex argentinus, Dosidicus gigas, Nototodarus sloani and Symplectoteuthis oualaniensis. According to the data statistics during 1992 to 2010, the Ommastrephidae production accounted for 51.15%-62.19% of cephalopods in the world, with an average of 55.40%. In this paper, the current exploitation and resources conditions of Todarodes pacificus, Illex argentinus, Dosidicus gigas and other squids are described in details. Meanwhile, according to the biological characteristics of short life cycle and fast growth, four major scientific issues which are to be resolved have been put forward. The four scientific issues are: (1) a completely comprehensive understanding of the ecological status and role of Ommastrephidae; (2) fully mastering the effect of environment including global climate change on the recruitment of Ommastrephidae; (3) further study of assessment model for Ommastrephidae based on the short life cycle; and (4) developing the ecosystem based resource management approaches for Ommastrephidae.
2012, 21(6):955-964.
Abstract:
From May to September in 2010, water quality parameters such as water temperature, total dissolved salt, dissolved oxygen, pH, transparency, nitrite nitrogen, ammonia nitrogen, nitrate nitrogen, total nitrogen, reactive phosphorus, total phosphorus, chlorophyll a and biochemical oxygen demand were analyzed in 22 Litopenaeus vannamei ponds with different culturing methods in Fengxian District, Shanghai. Water used for Farm No.1 was natural fresh water which had been precipitated before being introduced to the ponds. Mixed salt were added to the fresh water for culturing shrimp in Farm No.2. Results were as follows: water temperature, dissolved oxygen and pH didn’t change dramatically and could match the demand of Litopenaeus vannamei. The proportion of nitrate nitrogen in ponds to TIN was the highest, the ratio of ammonia nitrogen to TIN increased with time extension, and that of nitrite nitrogen to TIN increased obviously in the later period of culture cycle. Contents of reactive phosphorus decreased gradually while the total phosphorus increased in the whole process of culture. Biochemical oxygen demand and chlorophyll a also increased gradually with the shrimp growing up. Muscle nutritional quality of Litopenaeus vannamei from the two farms were analyzed and the results were as follows: contents of crude protein and crude fat of shrimp muscle in Farm No.1 were 16.30% and 1.42% respectively, lower than those in shrimp muscle from Farm No.2 which were 18.30% and 1.61%. Content of total amino acids in shrimp from Farm No.1was 23.27%, and the essential amino acid was 9.09%. While those in shrimp from Farm No.2 were 27.52% and 10.74%. Contents of flavor amino acids in shrimp from Farms No.1 and 2 were 8.52% and 10.16% respectively.
From May to September in 2010, water quality parameters such as water temperature, total dissolved salt, dissolved oxygen, pH, transparency, nitrite nitrogen, ammonia nitrogen, nitrate nitrogen, total nitrogen, reactive phosphorus, total phosphorus, chlorophyll a and biochemical oxygen demand were analyzed in 22 Litopenaeus vannamei ponds with different culturing methods in Fengxian District, Shanghai. Water used for Farm No.1 was natural fresh water which had been precipitated before being introduced to the ponds. Mixed salt were added to the fresh water for culturing shrimp in Farm No.2. Results were as follows: water temperature, dissolved oxygen and pH didn’t change dramatically and could match the demand of Litopenaeus vannamei. The proportion of nitrate nitrogen in ponds to TIN was the highest, the ratio of ammonia nitrogen to TIN increased with time extension, and that of nitrite nitrogen to TIN increased obviously in the later period of culture cycle. Contents of reactive phosphorus decreased gradually while the total phosphorus increased in the whole process of culture. Biochemical oxygen demand and chlorophyll a also increased gradually with the shrimp growing up. Muscle nutritional quality of Litopenaeus vannamei from the two farms were analyzed and the results were as follows: contents of crude protein and crude fat of shrimp muscle in Farm No.1 were 16.30% and 1.42% respectively, lower than those in shrimp muscle from Farm No.2 which were 18.30% and 1.61%. Content of total amino acids in shrimp from Farm No.1was 23.27%, and the essential amino acid was 9.09%. While those in shrimp from Farm No.2 were 27.52% and 10.74%. Contents of flavor amino acids in shrimp from Farms No.1 and 2 were 8.52% and 10.16% respectively.
20 Observation on molting and growth of adult Chinese mitten crab reared in the laboratory condition
2014, 23(3):359-365.
Abstract:
In this study, observation on molting and growth of Chinese mitten crab (Eriocheir sinensis) at adult stage (200 days) was carried out under laboratory conditions. The results showed that the average growth rate of body weight at the first to fourth molting stages was 48.7%, 69.1%, 80.1%, 64.8%, respectively; the average carapace length growth rate was 21.3%, 17.0%, 29.5%, 16.7%, respectively; the average carapace width growth rate was 17.4%, 18.3%, 28.2%, 18.1%, respectively. The body weight, carapace length and carapace width of male individuals were higher than those of female individuals at each molting stage, and the significant differences (P<0.05) were found since the third molting time. The average molting period was 37 days, 38 days, 29 days and 41 days for the first to fourth molting stages, respectively. The coefficient of variation of growth was higher at the first two molting stages than that at the latter two molting stages. The initial weight had significant effect (P<0.05) on the weight gained after each molting. There was significant difference (P<0.01) in weight,carapace length and carapace width among each molting stage, and the body weight after the third molting stage had significant correlation (P<0.05) with the weight at other molting stages. This result also showed the carapace length and carapace width had significant correlation(P<0.05) with the culturing temperature, however, the body weight had slightly significant difference (r=0.917-0.923, 0.05<P<0.10) with the culturing temperature. Generally, the present study showed that the growth rate was the highest at the third molting stage, indicating its important effect on the growth and culture practice at this stage. Meanwhile, the results showed that the larger size of juveniles, the larger size of adults would be.
In this study, observation on molting and growth of Chinese mitten crab (Eriocheir sinensis) at adult stage (200 days) was carried out under laboratory conditions. The results showed that the average growth rate of body weight at the first to fourth molting stages was 48.7%, 69.1%, 80.1%, 64.8%, respectively; the average carapace length growth rate was 21.3%, 17.0%, 29.5%, 16.7%, respectively; the average carapace width growth rate was 17.4%, 18.3%, 28.2%, 18.1%, respectively. The body weight, carapace length and carapace width of male individuals were higher than those of female individuals at each molting stage, and the significant differences (P<0.05) were found since the third molting time. The average molting period was 37 days, 38 days, 29 days and 41 days for the first to fourth molting stages, respectively. The coefficient of variation of growth was higher at the first two molting stages than that at the latter two molting stages. The initial weight had significant effect (P<0.05) on the weight gained after each molting. There was significant difference (P<0.01) in weight,carapace length and carapace width among each molting stage, and the body weight after the third molting stage had significant correlation (P<0.05) with the weight at other molting stages. This result also showed the carapace length and carapace width had significant correlation(P<0.05) with the culturing temperature, however, the body weight had slightly significant difference (r=0.917-0.923, 0.05<P<0.10) with the culturing temperature. Generally, the present study showed that the growth rate was the highest at the third molting stage, indicating its important effect on the growth and culture practice at this stage. Meanwhile, the results showed that the larger size of juveniles, the larger size of adults would be.
