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Examination of Silicate Limitation of Primary Production in Jiaozhou Bay, China Ⅱ. Critical Value and Time of Silicate Limitation and Satisfaction of the Phytoplankton Growth 被引量:32
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作者 杨东方 张经 +2 位作者 高振会 陈豫 孙培艳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第1期46-63,共18页
Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994 revealed the spatiotemporal variations of the ambient Si(OH) 4∶NO 3 (Si∶N) concentration ratios and the seasonal variations of (S... Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994 revealed the spatiotemporal variations of the ambient Si(OH) 4∶NO 3 (Si∶N) concentration ratios and the seasonal variations of (Si∶N) ratios in Jiaozhou Bay and showed that the Si∶N ratios were < 1 throughout Jiaozhou Bay in spring, autumn, and winter. These results provide further evidence that silicate limits the growth of phytoplankton (i.e. diatoms) in spring, autumn and winter. Moreover, comparison of the spatiotemporal variations of the Si∶N ratio and primary production in Jiaozhou Bay suggested their close relationship. The spatiotemporal pattern of dissolved silicate matched well that of primary production in Jiaozhou Bay. Along with the environmental change of Jiaozhou Bay in the last thirty years, the N and P concentrations tended to rise, whereas Si concentration showed cyclic seasonal variations. With the variation of nutrient Si limiting the primary production in mind, the authors found that the range of values of primary production is divided into three parts: the basic value of Si limited primary production, the extent of Si limited primary production and the critical value of Si limited primary production, which can be calculated for Jiaozhou Bay by Equations (1), (2) and (3), showing that the time of the critical value of Si limitation of phytoplankton growth in Jiaozhou Bay is around November 3 to November 13 in autumn; and that the time of the critical value of Si satisfaction of phytoplankton growth in Jiaozhou Bay is around May 22 to June 7 in spring. Moreover, the calculated critical value of Si satisfactory for phytoplankton growth is 2.15-0.76 μmol/L and the critical value of Si limitation of phytoplankton growth is 1.42-0.36 μmol/L; so that the time period of Si limitation of phytoplankton growth is around November 13 to May 22 in the next year; the time period of Si satisfactory for phytoplankton growth is around June 7 to November 3. This result also explains why critical values of nutrient 展开更多
关键词 PHYTOPLANKTON limitation and satisfaction critical value Jiaozhou Bay
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Examination of Silicate Limitation of Primary Production in Jiaozhou Bay,North ChinaⅢ.Judgment Method,Rules and Uniqueness of Nutrient Limitation Among N,P,and Si 被引量:28
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作者 杨东方 高振会 +2 位作者 陈豫 张经 王培刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第2期114-133,共20页
Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994(12 seasonal investigations) provided by the Ecological Station of Jiaozhou Bay revealed the characteristic spatiotemporal variation... Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994(12 seasonal investigations) provided by the Ecological Station of Jiaozhou Bay revealed the characteristic spatiotemporal variation of the ambient concentration Si:DIN and Si:16P ratios and the seasonal variation of Jiaozhou Bay Si:DIN and Si:16P ratios showing that the Si:DIN ratios were < 1 throughout the year in Jiaozhou Bay; and that the Si:16P ratios were < 1 throughout Jiaozhou Bay in spring, autumn and winter. The results proved that silicate limited phytoplankton growth in spring, autumn and winter in Jiaozhou Bay. Analysis of the Si:DIN and Si:P ratios showed that the nutrient Si has been limiting the growth of phytoplankton throughout the year in some Jiaozhou Bay waters; and that the silicate deficiency changed the phytoplankton assemblage structure. Analysis of discontinuous 1962 to 1998 nutrient data showed that there was no N or P limitation of phytoplankton growth in that period. The authors consider that the annual cyclic change of silicate limits phytoplankton growth in spring, autumn and winter every year in Jiaozhou Bay; and that in many Jiaozhou Bay waters where the phytoplankton as the predominant species need a great amount of silicate, analysis of the nutrients N or P limitation of phytoplankton growth relying only on the N and P nutrients and DIN:P ratio could yield inaccurate conclusions. The results obtained by applying the rules of absolute and relative limitation fully support this view. The authors consider that the main function of nutrient silicon is to regulate and control the mechanism of the phytoplankton growth process in the ecological system in estuaries, bays and the sea. The authors consider that according to the evolution theory of Darwin, continuous environmental pressure gradually changes the phytoplankton assemblage's structure and the physiology of diatoms. Diatoms requiring a great deal of silicon either constantly decrease or reduce their requirement for silicon. This will cause 展开更多
关键词 PHYTOPLANKTON SILICATE limiting factor Jiaozhou Bay
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Impacts of changing scale on Getis-Ord Gi* hotspots of CPUE:a case study of the neon flying squid (Ommastrephes bartramii)in the northwest Pacific Ocean 被引量:26
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作者 FENG Yongjiu CHEN Xinjun +1 位作者 GAO Feng LIU Yang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第5期67-76,共10页
We examined the scale impacts on spatial hot and cold spots of CPUE for Ommastrephes bartramii in the northwest Pacific Ocean. The original fishery data were tessellated to 18 spatial scales from 5′×5′ to 90′&... We examined the scale impacts on spatial hot and cold spots of CPUE for Ommastrephes bartramii in the northwest Pacific Ocean. The original fishery data were tessellated to 18 spatial scales from 5′×5′ to 90′×90′ with a scale interval of 5′ to identify the local clusters. The changes in location, boundaries, and statistics regarding the Getis-Ord Gi* hot and cold spots in response to the spatial scales were analyzed in detail. Several statistics including Min, mean, Max, SD, CV, skewness, kurtosis, first quartile(Q1), median, third quartile(Q3), area and centroid were calculated for spatial hot and cold spots. Scaling impacts were examined for the selected statistics using linear, logarithmic, exponential, power law and polynomial functions. Clear scaling relations were identified for Max, SD and kurtosis for both hot and cold spots. For the remaining statistics, either a difference of scale impacts was found between the two clusters, or no clear scaling relation was identified. Spatial scales coarser than 30′ are not recommended to identify the local spatial patterns of fisheries because the boundary and locations of hot and cold spots at a coarser scale are significantly different from those at the original scale. 展开更多
关键词 Ommastrephes bartramii scale impacts local clusters Getis-Ord Gi* spatial hotspots
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A Review of Interaction Between Neon Flying Squid(Ommastrephes bartramii) and Oceanographic Variability in the North Pacific Ocean 被引量:26
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作者 YU Wei CHEN Xinjun +1 位作者 YI Qian TIAN Siquan 《Journal of Ocean University of China》 SCIE CAS 2015年第4期739-748,共10页
The neon flying squid (Ommastrephes bartramii) is a short-lived opporttmistic species widely distributed in subtropical and temperate waters in the North Pacific Ocean. The life cycle of O. bartramii from planktonic... The neon flying squid (Ommastrephes bartramii) is a short-lived opporttmistic species widely distributed in subtropical and temperate waters in the North Pacific Ocean. The life cycle of O. bartramii from planktonic eggs to nektonic adults is closely linked to oceanographic conditions. The fluctuations in O. bartramii abundance and distribution tend to increase and widen continu- ously due to the heavy influences of ocean-climate events on various spatio-temporal scales. In this study, we reviewed the interac- tion between O. bartramii and oceanography variability in the North Pacific with respect to large-scale climatic-oceanic phenomena including E1 Nifio, La Nifia, Kuroshio, Oyashio and Pacific Decadal Oscillation (PDO), as well as regional environmental variables such as sea surface temperature (SST), sea surface height (SSH), sea surface salinity (SSS), chlorophyll-a (Chl-a) concentration, and plankton density. The population dynamics of O. bartramii is mediated mainly by meso- and large-scale climatic-oceanic events (e.g., Kuroshio and Oyashio Currents) rather than other local environmental conditions (e.g., SST and Chl-a concentration), because all of the oceanographic influences are imposed on the context of large-scale climate changes (e.g., PDO). An unstructured-grid finite- volume coastal ocean model coupled with an individual-based model is proposed to simulate relevant physical-biological oceano- graphic processes for identifying ocean-climate influence and predicting O. bartramii distribution and abundance in the North Pacific. Future research needs to be focused on improving the knowledge about early life history of O. bartramii and evaluating the relation- ship between marine physical environment and two separate passive drifting life stages of O. bartramii including free-floating eggs and planktonic paralarvae. 展开更多
关键词 Ommastrephes bartramii oceanographic influence early life history physical-biological model North Pacific Ocean
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Genome Sequences Provide Insights into the Reticulate Origin and Unique Traits of Woody Bamboos 被引量:22
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作者 Zhen-Hua Guo Peng-Fei Ma +22 位作者 Guo-Qian Yang Jin-Yong Hu Yun-Long Liu En-Hua Xia Mi-Cai Zhong Lei Zhao Gui-Ling Sun Yu-Xing Xu You-Jie Zhao Yi-Chi Zhang Yu-Xiao Zhang Xue-Mei Zhang Meng-Yuan Zhou Ying Guo Cen Guo Jing-Xia Liu Xia-Ying Ye Yun-Mei Chen Yang Yang Bin Han Choun-Sea Lin Ying Lu De-Zhu Li 《Molecular Plant》 SCIE CAS CSCD 2019年第10期1353-1365,共13页
Polyploidization is a major driver of speciation and its importance to plant evolution has been well recognized.Bamboos comprise one diploid herbaceous and three polyploid woody lineages,and are members of the only ma... Polyploidization is a major driver of speciation and its importance to plant evolution has been well recognized.Bamboos comprise one diploid herbaceous and three polyploid woody lineages,and are members of the only major subfamily in grasses that diversified in forests,with the woody members having a tree-like lignified culm.In this study,we generated four draft genome assemblies of major bamboo lineages with three different ploidy levels(diploid,tetraploid,and hexaploid).We also constructed a high-density genetic linkage map for a hexaploid species of bamboo,and used a linkage-map-based strategy for genome assembly and identification of subgenomes in polyploids.Further phylogenomic analyses using a large dataset of syntenic genes with expected copies based on ploidy levels revealed that woody bamboos originated subsequent to the divergence of the herbaceous bamboo lineage,and experienced complex reticulate evolution through three independent allopolyploid events involving four extinct diploid ancestors.A shared but distinct subgenome was identified in all polyploid forms,and the progenitor of this subgenome could have been critical in ancient polyploidizations and the origin of woody bamboos.Important genetic clues to the unique flowering behavior and woody trait in bamboos were also found.Taken together,our study provides significant insights into ancient reticulate evolution at the subgenome level in the absence of extant donor species,and offers a potential model scenario for broad-scale study of angiosperm origination by allopolyploidization. 展开更多
关键词 BAMBUSOIDEAE POLYPLOIDIZATION comparative GENOMICS subgenome evolution FLOWERING
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Age, maturation, and population structure of the Humboldt squid Dosidicus gigas off the Peruvian Exclusive Economic Zones 被引量:22
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作者 刘必林 陈新军 +4 位作者 陈勇 田思泉 李建华 方舟 杨铭霞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期81-91,共11页
Age, maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones (EEZ) during 2008-2010. E... Age, maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones (EEZ) during 2008-2010. Estimated ages ranged from 144 to 633 days, confirming that the squid is a short-lived species with longevity no longer than 2 years. Occurrence of mature females and hatching in each month indicated that Humboldt squid spawned year-round. Back-calculated hatching dates for the samples were from January 22^nd, 2008 to April 22nd, 2010 with a peak between January and March. Two size-based and two hatching date-based populations could be defined from mantle length (ML) at maturity and back-calculated hatching dates, respectively. Females matured at a larger size than males, and there was a significant difference in ML at maturity between the two hatching groups (P〈0.05). The waters adjacent to 1 l^S off the Peruvian EEZ may be a potential spawning ground. This study shows the complexity of the population structure and large variability in key life history parameters in the Humboldt squid off the Peruvian EEZ, which should be considered in the assessment and management of this important resource. 展开更多
关键词 Dosidicus gigas offPeruvian EEZ age MATURATION population structure STATOLITH
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Standardizing CPUE of Ommastrephes bartramii for Chinese squid-jigging fishery in Northwest Pacific Ocean 被引量:15
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作者 田思泉 陈新军 +2 位作者 陈勇 许柳雄 戴小杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第4期729-739,共11页
Generalized linear models (GLM) and generalized additive models (GAM) were used to standardize catch per unit fishing effort (CPUE) of Ommastrephes bartramii for Chinese squid-jigging fishery in Northwest Pacifi... Generalized linear models (GLM) and generalized additive models (GAM) were used to standardize catch per unit fishing effort (CPUE) of Ommastrephes bartramii for Chinese squid-jigging fishery in Northwest Pacific Ocean. Three groups of variables were considered in the standardization: spatial variables (longitude and latitude), temporal variables (year and month) and environmental variables, including sea surface temperature (SST), sea surface salinity (SSS) and sea level height (SLH). CPUE was treated as the dependent variable and its error distribution was assumed to be log-normal in each model. The model selections of GLM and GAM were based on the finite sample-corrected Akaike information criterion (AICC) and pseudo-coefficient (Pcf) combined P-value, respectively. Both GAM and GLM analysis showed that the month was the most important variable affecting CPUE and could explain 21.3% of variability in CPUE while other variables only explained 8.66%. The interaction of spatial and temporal variables weakly influenced the CPUE. Moreover, spatio-temporal factors may be more important in influencing the CPUE of this squid than environmental variables. The standardized and nominal CPUEs were similar and had the same trends in spatio-temporal distribution, but the standardized CPUE values tended to be smaller than the nominal CPUE. The CPUE tended to have much higher monthly variation than annual variations and their values increased with month. The CPUE became higher with increasing latitude-high CPUE usually occurred in 145°E-148°E and 149°E-162°E. The CPUE was higher when SST was 14-21℃ and the SLH from -22 cm to -18 cm. In this study, GAM tended to be more suitable than GLM in analysis of CPUE. 展开更多
关键词 Ommastrephes bartramii CPUE standardization generalized additive model generalizedlinear model Northwestern Pacific Ocean Chinese squid-jigging fishery
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The effect of sea surface temperature increase on the potential habitat of Ommastrephes bartramii in the Northwest Pacific Ocean 被引量:11
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作者 XU Jie CHEN Xinjun +2 位作者 CHEN Yong DING Qi TIAN Siquan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第2期109-116,共8页
In the Northwest Pacific Ocean, the squid jigging fisheries from China, Japan and other countries and regions have targeted the west winter-spring cohort of neon flying squid(Ommastrephes bartramii) from August to N... In the Northwest Pacific Ocean, the squid jigging fisheries from China, Japan and other countries and regions have targeted the west winter-spring cohort of neon flying squid(Ommastrephes bartramii) from August to November since the 1970 s. This squid is a short-lived ecological opportunist with a life-span of about one year,and its population is labile and recruitment variability is driven by the environment or climate change. This variability provides a challenge for ones to forecast the key habitats affected by climate change. The catch data of O. bartramii from Chinese squid jigging fishery and the satellite-derived sea surface temperature(SST) data are used in the Northwest Pacific Ocean from August to November of 1998 to 2004, the SST preferences of O.bartramii corresponding to high values of catch per fishing day(CPUE) are determined and monthly potential habitats are predicted using a histogram analysis of the SST data. The possible changes in the potential habitats of O. bartramii in the Northwest Pacific Ocean are estimated under four climate change scenarios based on the Fourth Assessment Report(AR4) of the Intergovernmental Panel on Climate Change, i.e., 0.5, 1, 2 and 4°C increases in the SST because of the climate change. The results reveal an obvious poleward shift of the potential habitats of O. bartramii in the Northwest Pacific Ocean. 展开更多
关键词 Ommastrephes bartramii sea surface temperature increase potential habitat Northwest Pacific Ocean
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Application of a Bayesian method to data-poor stock assessment by using Indian Ocean albacore (Thunnus alalunga) stock assessment as an example 被引量:14
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作者 GUAN Wenjiang TANG Lin +2 位作者 ZHU Jiangfeng TIAN Siquan XU Liuxiong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第2期117-125,共9页
It is widely recognized that assessments of the status of data-poor fish stocks are challenging and that Bayesian analysis is one of the methods which can be used to improve the reliability of stock assessments in dat... It is widely recognized that assessments of the status of data-poor fish stocks are challenging and that Bayesian analysis is one of the methods which can be used to improve the reliability of stock assessments in data-poor situations through borrowing strength from prior information deduced from species with good-quality data or other known information. Because there is considerable uncertainty remaining in the stock assessment of albacore tuna(Thunnus alalunga) in the Indian Ocean due to the limited and low-quality data, we investigate the advantages of a Bayesian method in data-poor stock assessment by using Indian Ocean albacore stock assessment as an example. Eight Bayesian biomass dynamics models with different prior assumptions and catch data series were developed to assess the stock. The results show(1) the rationality of choice of catch data series and assumption of parameters could be enhanced by analyzing the posterior distribution of the parameters;(2) the reliability of the stock assessment could be improved by using demographic methods to construct a prior for the intrinsic rate of increase(r). Because we can make use of more information to improve the rationality of parameter estimation and the reliability of the stock assessment compared with traditional statistical methods by incorporating any available knowledge into the informative priors and analyzing the posterior distribution based on Bayesian framework in data-poor situations, we suggest that the Bayesian method should be an alternative method to be applied in data-poor species stock assessment, such as Indian Ocean albacore. 展开更多
关键词 data-poor stock assessment Bayesian method catch data series demographic method Indian Ocean Thunnus alalunga
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OsMADS16 Genetically Interacts with OsMADS3 and OsMADS58 in Specifying Floral Patterning ~in Rice 被引量:13
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作者 Dapeng Yun Wanqi Liang +4 位作者 Ludovico Dreni Changsong Yin Zhigang Zhou Martin M. Kater Dabing Zhang 《Molecular Plant》 SCIE CAS CSCD 2013年第3期743-756,共14页
Rice (Oryza sativa) has unique floral patterns that contribute to grain yield. However, the molecular mechanism underlying the specification of floral organ identities in rice, particularly the interaction among flo... Rice (Oryza sativa) has unique floral patterns that contribute to grain yield. However, the molecular mechanism underlying the specification of floral organ identities in rice, particularly the interaction among floral homeotic genes, remains poorly understood. Here, we show that the floral homeotic gene OsMADS16 (also called SUPERWOMAN1, SPWl, a B-class gene) acts together with the rice C-class genes OsMADS3 and OsMADS58 in specifying floral organ patterning. OsMADS16 and the two C-class genes have an overlapping expression pattern in the third whorl founder cells. Compared with the single mutants, both spwl-1 osmads3-4 and spwl-1 osmads58 double mutants exhibit additional whorls of glume-like organs within the flower, particularly an extra whorl of six glume-like structures formed at the position of the wild-type stamens. These ectopic glume-like structures were shown to have palea identity through cellular observation and in situ hybridization analysis using marker genes. Our results suggest that B- and C-class genes play a key role in suppressing indeterminate growth within the floral meristem, particularly whorl-3 primordia. We also hypothesize that, in contrast to previous assumptions, the specialized spikelet organ in rice, the palea, is the counterpart of the sepal in eudicots, and the lemma is homologous to the bract. 展开更多
关键词 RICE FLOWER B and C genes genetic interaction stamen identity.
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Silicon limitation on primary production and its destiny in Jiaozhou Bay,China V:Silicon deficit process 被引量:13
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作者 杨东方 高振会 +2 位作者 王培刚 孙培艳 刘霜 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第2期169-175,共7页
Silicon is a necessary nutrient for diatoms, silicon uptake in diatom reproduction decreased sea- water silicon content. This paper clarified the characteristics of silicon transferring in the sea, which plays an impo... Silicon is a necessary nutrient for diatoms, silicon uptake in diatom reproduction decreased sea- water silicon content. This paper clarified the characteristics of silicon transferring in the sea, which plays an important role in phytoplankton growth, zooplankton graze and marine ecosystem. Analysis revealed that silicate is supplied by terrestrial sources, through plankton uptake, death, and eventually deposits to the sea bottom, and cannot diffuse upward. This is a general silicon deficit process. Many global marine waters showed the same silicon transfer route: land→silicon biogeochemical process→sea bottom. River flow brings abundant silicate into marine waters, silicate concentration in the waters decreased in the distance away from the river estuaries. In discussion of silicon characteristics and its transfer route, it was considered that the main factor controlling the mechanism of diatom and non-diatom red tides occurrence is silicon, and the changes in silicon source. Human activities, such as sea-route cutting by building embankment and dam, and silicon supplement by the sea, such as sandstorm, rainstorm and storm tide, have largely impaired the earth ecosystem and hugely threatened the human existence. It is suggested in this paper that man should resume the original face of the Si input into the sea to keep natural ecosystem in sustainable pattern. 展开更多
关键词 SILICON biogeochemical process deficit process global waters
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Variations of oceanic fronts and their influence on the fishing grounds of Ommastrephes bartramii in the Northwest Pacific 被引量:13
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作者 CHEN Xinjun TIAN Siquan GUAN Wenjian 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第4期45-54,共10页
Two predominant currents, the warm Kuroshio Current and the cold Oyashio Current, meet in the North- west Pacific Ocean. The dynamics of physical oceanographic structures in this region, including frontal zones and me... Two predominant currents, the warm Kuroshio Current and the cold Oyashio Current, meet in the North- west Pacific Ocean. The dynamics of physical oceanographic structures in this region, including frontal zones and meandering eddies, result in a highly productive habitat that serves as a favorable feeding ground for various commercially important species. Neon flying squid, Ommastrephes bartramii, is an im- portant oceanic squid, which is widely distributed in the North Pacific Ocean. Based on the catch data col- lected by Chinese squid jigging fleets and relevant environmental data, including sea surface temperature (SST) and fronts (represented by gradients of SST and thermocline) during 1998-2009, the variations of oceanic fronts and their influence on the fishing grounds of O. bartramii were evaluated, and the differ- ences in distribution of fishing grounds of O. bartramii in 2000 and 2002 were compared by describing the differences in vertical temperature between 0-300 m. It was found that the preferred horizontal tem- perature gradient of SST for O. bartramii tended to be centered at 0.01-0.02~C/nm, which attracted nearly 80% of the total fishing effort, and the preferred horizontal temperature gradients at the 50 m and 105 m layers were mainly located at 0.01-0.03~C/nm, which accounted for more than 70% of the total fishing effort during August-October. The preferred vertical temperature gradient within the 0-50 m layer for O. bartramii tended to be centered at 0.15-0.25~C/m during August and September and at 0.10-0.15~C/m in October, implying that the mixed surface layer was distributed at depths of 0-50 m. It was concluded that the vertical temperature gradient was more important than the horizontal temperature gradient in playing a role in forming the fishing ground. The results improved our understanding of the spatial dynamics of the 0. bartramii fishery. 展开更多
关键词 Ommastrephe bartramii fishing ground ocean front interannual variation Northwest Pacific
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Age and Growth of Chub Mackerel (Scomber japonicus) in the East China and Yellow Seas Using Sectioned Otolith Samples 被引量:12
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作者 LI Gang CHEN Xinjun FENG Bo 《Journal of Ocean University of China》 SCIE CAS 2008年第4期439-446,共8页
Although chub mackerel (Scomberjaponicus) is a primary pelagic fish species, we have only limited knowledge on its key life history processes. The present work studied the age and growth of chub mackerel in the East... Although chub mackerel (Scomberjaponicus) is a primary pelagic fish species, we have only limited knowledge on its key life history processes. The present work studied the age and growth of chub mackerel in the East China and Yellow Seas. Age was determined by interpreting and counting growth rings on the sagitta otoliths of 252 adult fish caught by the Chinese commercial purse seine fleet during the period from November 2006 to January 2007 and 150 juveniles from bottom trawl surveys on the spawning ground in May 2006. The difference between the assumed birth date of 1st April and date of capture was used to adjust the age determined from counting the number of complete translucent rings. The parameters of three commonly used growth models, the von Bertalanffy, Logistic and Gompertz models, were estimated using the maximum likelihood method. Based on the Akaike Information Criterion (AIC), the yon Bertalanffy growth model was found to be the most appropriate model. The size-at-age and size-at-maturity values were also found to decrease greatly compared with the results achieved in the 1950s, which was caused by heavy exploitation over the last few decades. 展开更多
关键词 Scomber japonicus age GROWTH OTOLITH East China and Yellow Seas
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Modeling a habitat suitability index for the eastern fall cohort of Ommastrephes bartramii in the central North Pacific Ocean 被引量:12
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作者 陈新军 田思泉 +1 位作者 刘必林 陈勇 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第3期493-504,共12页
The eastern fall cohort of the neon flying squid, Ommastrephes bartramii, has been commercially exploited by the Chinese squid jigging fleet in the central North Pacific Ocean since the late 1990s. To understand and i... The eastern fall cohort of the neon flying squid, Ommastrephes bartramii, has been commercially exploited by the Chinese squid jigging fleet in the central North Pacific Ocean since the late 1990s. To understand and identify their optimal habitat, we have developed a habitat suitability index (HSI) model using two potential important environmental variables -- sea surface temperature (SST) and sea surface height anomaly (SSHA) -- and fishery data from the main fishing ground (165°-180°E) during June and July of 1999-2003. A geometric mean model (GMM), minimum model (MM) and arithmetic weighted model (AWM) with different weights were compared and the best HSI model was selected using Akaike's information criterion (AIC). The performance of the developed HSI model was evaluated using fishery data for 2004. This study suggests that the highest catch per unit effort (CPUE) and fishing effort are closely related to SST and SSHA. The best SST- and SSHA-based suitability index (SI) regression models were SISST-based = 0.7SIeffort-SST + 0.3 SICPUE-SST, and SISSHA-based =0.5Sleffort-SSHA + 0.5SICPUE-SSHA, respectively, showing that fishing effort is more important than CPUE in the estimation of SI. The best HSI model was the AWM, defined as HSI=0.3SISSHA-based+ 0.7SISSHA-based, indicating that SSHA is more important than SST in estimating the HSI of squid. In 2004, monthly HSI values greater than 0.6 coincided with the distribution of productive fishing ground and high CPUE in June and July, suggesting that the models perform well. The proposed model provides an important tool in our efforts to develop forecasting capacity of squid spatial dynamics. 展开更多
关键词 model habitat suitability index eastern fall cohort of Ommastrephes bartramii fishing effort CPUE central North Pacific Ocean
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Importance of Weighting for Multi-Variable Habitat Suitability Index Model: A Case Study of Winter- Spring Cohort of Ommastrephes bartramii in the Northwestern Pacific Ocean 被引量:12
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作者 GONG Caixia CHEN Xinjun +1 位作者 GAO Feng CHEN Yong 《Journal of Ocean University of China》 SCIE CAS 2012年第2期241-248,共8页
Weighting values for different habitat variables used in multi-factor habitat suitability index (HSI) modeling reflect the relative influences of different variables on distribution of fish species. Using the winter-s... Weighting values for different habitat variables used in multi-factor habitat suitability index (HSI) modeling reflect the relative influences of different variables on distribution of fish species. Using the winter-spring cohort of neon flying squid (Ommastrephes bartramii) in the Northwestern Pacific Ocean as an example, we evaluated the impact of different weighting schemes on the HSI models based on sea surface temperature, gradient of sea surface temperature and sea surface height. We compared differences in predicted fishing effort and HSI values resulting from different weighting. The weighting for different habitat variables could greatly influence HSI modeling and should be carefully done based on their relative importance in influencing the resource spatial distribution. Weighting in a multi-factor HSI model should be further studied and optimization methods should be developed to improve forecasting squid spatial distributions. 展开更多
关键词 weighting multi-factors habitat suitability index model Ommastrephes bartramii Northwestern Pacific Ocean
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Modeling the Hook Depth Distribution of Pelagic Longlining in the Equatorial Area of Indian Ocean 被引量:10
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作者 SONG Liming LI Jie +2 位作者 GAO Panfeng ZHOU Ji XU Liuxiong 《Journal of Ocean University of China》 SCIE CAS 2012年第4期547-556,共10页
A survey was conducted in the equatorial area of Indian Ocean for a better understanding of the dynamics of hook depth distribution of pelagic longline fishery. We determined the relationship between hook depth and ve... A survey was conducted in the equatorial area of Indian Ocean for a better understanding of the dynamics of hook depth distribution of pelagic longline fishery. We determined the relationship between hook depth and vertical shear of current coefficieney, wind speed, hook position code, sine of wind angle, sine of angle of attack and weight of messenger weight. We identified the hook depth models by the analysis of covariance with a general linear model. The results showed that the wind effect on the hook depth can be ignored from October to November in the survey area; the surface current effect on the hook depth can be ignored; the equato- rial undercurrent is the key factor for the hook depth in Indian Ocean; and there is a negative correlation between the hook depth and vertical shear of current and angle of attack. It was also found that the deeper the hook was set, the higher hook depth shoaling was. The proposed model improves the accuracy of the prediction of hook depth, which can be used to estimate the vertical distribution of pelagic fish in water column. 展开更多
关键词 hook depth LONGLINE temperature-depth-recorder equatorial area the Indian Ocean
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Cell metabolism pathways involved in the pathophysiological changes of diabetic peripheral neuropathy 被引量:5
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作者 Yaowei Lv Xiangyun Yao +3 位作者 Xiao Li Yuanming Ouyang Cunyi Fan Yun Qian 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期598-605,共8页
Diabetic peripheral neuropathy is a common complication of diabetes mellitus.Elucidating the pathophysiological metabolic mechanism impels the generation of ideal therapies.However,existing limited treatments for diab... Diabetic peripheral neuropathy is a common complication of diabetes mellitus.Elucidating the pathophysiological metabolic mechanism impels the generation of ideal therapies.However,existing limited treatments for diabetic peripheral neuropathy expose the urgent need for cell metabolism research.Given the lack of comprehensive understanding of energy metabolism changes and related signaling pathways in diabetic peripheral neuropathy,it is essential to explore energy changes and metabolic changes in diabetic peripheral neuropathy to develop suitable treatment methods.This review summarizes the pathophysiological mechanism of diabetic peripheral neuropathy from the perspective of cellular metabolism and the specific interventions for different metabolic pathways to develop effective treatment methods.Various metabolic mechanisms(e.g.,polyol,hexosamine,protein kinase C pathway)are associated with diabetic peripheral neuropathy,and researchers are looking for more effective treatments through these pathways. 展开更多
关键词 cell metabolism diabetic peripheral neuropathy peripheral nerve injury protein kinase C pathway reactive oxygen species.
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Effects of environmental variations on the abundance of western winter-spring cohort of neon flying squid(Ommastrephes bartramii) in the Northwest Pacific Ocean 被引量:10
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作者 YU Wei CHEN Xinjun +2 位作者 CHEN Yong YI Qian ZHANG Yang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第8期43-51,共9页
During 1995-2011, annual production of winter-spring cohort of Ommastrephes bartramii for Chinese squidjigging fishery has greatly fluctuated, which is closely related to the environmental conditions on the spawning a... During 1995-2011, annual production of winter-spring cohort of Ommastrephes bartramii for Chinese squidjigging fishery has greatly fluctuated, which is closely related to the environmental conditions on the spawning and fishing grounds. To better understand how squid recruitment and abundance were infuenced by ocean environmental conditions, biological and physical environmental variables including sea surface temperature (SST), SST anomaly (SSTA), chlorophyll a (Chl a) concentration and the Kuroshio Current were examined during years with the highest (1999), intermediate (2005), and lowest (2009) catches. Catch per unit effort (CPUE) of the squid-jigging vessels was used as an indicator of squid abundance. The results indicated that high SST and Chl a concentration on the spawning ground in 1999 resulted in favorable incubation and feeding conditions for squid recruitment. Whereas the suitable spawning zone (SSZ) in 2009 shifted southward and coincided with low SST and Chl a concentration, resulting in a reduction in the squid recruitment. The small difference of SSZ area in the three years suggested the SSZ provided limited influences on the variability in squid recruitment. Furthermore, high squid abundance in 1999 and 2005 was associated with warm SSTA on the fishing ground. While the cool SSTA on the fishing ground in 2009 contributed to adverse habitat for the squid, leading to extremely low abundance. It was inferred that strengthened intensity of the Kuroshio force generally yielded favorable environmental conditions for O. bartramii. Future research are suggested to focus on the fundamental research oil the early life stage of O. bartramii and mechanism of how the ocean-climate variability affects the squid abundance and spatial distribution by coupling physical model with squid biological process to explore transport path and abundance distribution. 展开更多
关键词 Ommastrephes bartramii environmental conditions RECRUITMENT ABUNDANCE Northwest Pacific Ocean
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Impacts of oceanographic factors on interannual variability of the winter-spring cohort of neon flying squid abundance in the Northwest Pacific Ocean 被引量:10
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作者 YU Wei CHEN Xinjun +1 位作者 CHEN Changsheng ZHANG Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第10期48-59,共12页
The neon flying squid Ommastrephes bartramii is an economically important species in the Northwest Pacific Ocean. The life cycle of O. bartramii is highly susceptible to climatic and oceanic factors. In this study, we... The neon flying squid Ommastrephes bartramii is an economically important species in the Northwest Pacific Ocean. The life cycle of O. bartramii is highly susceptible to climatic and oceanic factors. In this study, we have examined the impacts of climate variability and local biophysical environments on the interannual variability of the abundance of the western winter-spring cohort of O. bartramii over the period of 1995–2011. The results showed that the squid had experienced alternant positive and negative Pacific Decadal Oscillation(PDO) over the past 17 years during which five El Ni?o and eight La Ni?a events occurred. The catch per unit effort(CPUE) was positively correlated with the PDO index(PDOI) at a one-year time lag. An abnormally warm temperature during the La Ni?a years over the positive PDO phase provided favorable oceanographic conditions for the habitats of O.bartramii, whereas a lower temperature on the fishing ground during the El Ni?o years over the negative PDO phase generally corresponded to a low CPUE. The same correlation was also found between CPUE and Chl a concentration anomaly. A possible explanation was proposed that the CPUE was likely related to the climateinduced variability of the large-scale circulation in the Northwest Pacific Ocean: high squid abundance often occurred in a year with a significant northward meander of the Kuroshio Current. The Kuroshio Current advected the warmer and food-rich waters into the fishing ground, and multiple meso-scale eddies arising from current instability enhanced the food retention on the fishing ground, all of which were favorable for the life stage development of the western squid stocks. Our results help better understand the potential process that the climatic and oceanographic factors affect the abundance of the winter-spring cohort of O. bartramii in the Northwest Pacific Ocean. 展开更多
关键词 Ommastrephes bartramii squid abundance interannual variability PDO-CPUE relationship Kuroshio meandering meso-scale eddies
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Examination of Daytime Length's Influence on Phytoplankton Growth in Jiaozhou Bay, China 被引量:12
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作者 杨东方 高振会 +2 位作者 张经 崔文林 石强 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第1期70-82,共13页
This study showed how the daytime length in Jiaozhou Bay affected the water temperature, which in turn affected the phytoplankton growth when solar radiation was sufficient for phytoplankton photosynthesis. Jiaozhou B... This study showed how the daytime length in Jiaozhou Bay affected the water temperature, which in turn affected the phytoplankton growth when solar radiation was sufficient for phytoplankton photosynthesis. Jiaozhou Bay observation data collected from May 1991 to February 1994 were used to analyze the daytime length vs water temperature relationship. Our study showed that daytime length and the variation controlled the cycle of water temperature flunctuation. Should the cyclic variation curve of the daytime length be moved back for two months it would be superimposed with temperature change. The values of daytime length and temperature that calculated in the dynamical model of daytime length lag vs water temperature were consistent with observed values. The light radiation and daytime length in this model determined the photochemistry process and the enzymic catalysis process of phytoplankton photosynthesis. In addition, by considering the effect of the daytime length on water temperature and photosynthesis, we could comprehend the joint effect of daytime length, water temperature, and nutrients, on the spatiotemporal variation of primary production in Jiaozhou Bay. 展开更多
关键词 daytime length water temperature primary production Jiaozhou Bay
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