Design and Analysis of Elastic Component of Resonant Cylinder Pressure Sensor

利用有限元分析软件AnSyS对振筒式压力传感器弹性元件——谐振筒进行了动态特性仿真分析,建立了谐振筒的参数化模型,基于模态分析选定合适的工作振型,重点利用谐响应分析讨论了谐振筒品质因数的影响因素。研究表明,当谐振筒的基模态为(4,1)模态时,品质因数随谐振筒外半径、有效长度以及壁厚的增加而减小,而工作时作用于谐振筒的激励载荷只改变了谐振筒振幅大小,对品质因数无明显影响。通过瞬态动力学分析计算得到谐振筒的调节时间,证明了谐振筒具有较好的动态响应特性。为谐振筒的结构设计和优化提供了参考。Simulation and analysis on dynamic behavior of resonant cylinder which composed the pressure sensor as the elastic component are conducted using the finite element analysis software ANSYS.Parametric model is established.Based on the modal analysis,an appropriate mode for work is selected out.Factors affecting quality factor are discussed mainly through harmonic response analysis.Results indicate that,when the cylinder worked on(4,1) mode,quality factor would decreases as radius,effective length or thickness increase,while the force only had an influence on the amplitude of the vibration rather than the quality factor.Adjusting time is obtained by transient dynamic analysis,thus proving the rapidity of resonant cylinder.The study provides reference both for structure design and optimization

Electrohydrodynamic printing for head with retractable needle

设计了一种新型的基于电液动力学的喷头,该喷头内含一个可伸缩的针尖。由这种喷头组成的喷印系统,在不同的条件下可以产生离散的点和珠状结构两种喷射模式。结果表明:溶液浓度是区分这两种喷射模式的关键因素。当喷射溶液的浓度比较低时,喷印系统喷射出离散的圆点;当较高时,喷射出珠状结构。其珠状结构中珠子的直径随着系统供液速率的增加而变大,随着PEO溶液浓度的提高和针尖频率的增加而减小。改变收集板的移动速度,可以改变喷射沉积物形态,且该系统的喷射频率与可伸缩针尖的运动频率之间有很好的线性相关性。A novel electrohydrodynamic printing system with a retractable needle was designed,by which both ejection modes of dots and bead-on-string structures can be produced.Experimental results show that solution concentration is the key element to define the ejection mode.Dots can be obtained for lower solution concentration,otherwise bead-on-string structures would be produced.the diameter of deposition dots increases with the increasing of supply rate,and decreases with the increasing of PEO solution concentration and the frequency increasing of needle.By changing the speed of collector,different morphologies of depositions can be obtained.In addition,the deposition frequency has a close relationship with the retractable frequency of needle.中央高校基本科研业务费专项资金(2010121039);国家自然科学基金(51035002;50875222

Fish species diversity and community pattern in coral reefs of the Xisha Islands,South China Sea

为了解珊瑚礁海域鱼类物种多样性及其群落特征,作者2003年5月在西沙群岛7座主要岛礁(北礁、华光礁、金银岛、东岛、浪花礁、玉琢礁和永兴岛)采用底层刺网进行了调查,运用聚类分析和非度量多维标度(nMdS)等多元统计分析方法,对7个岛礁鱼类的种类组成、优势种、多样性和群落格局进行了分析。调查海域共记录鱼类146种,隶属10目31科;各主要岛礁的鱼类以典型的热带种类为主,如鹦嘴鱼科、蝴蝶鱼科、笛鲷科等珊瑚礁鱼类;白边锯鳞鳂(MyrIPrISTIS MurdJAn)、四带笛鲷(luTJAnuS kASMIrA)、灰若梅鲷(PArACAESIO SOrdIduS)、双带梅鲷(CAESIO dIAgrAMMA)、单板盾尾鱼(AXInuruS THynnOIdES)和灰六鳃鲨(HEXAnCHuS grISEuS)为主要优势种;全海域鱼类的SHAnnOn-WIEnEr多样性指数(H')在1.91–3.33之间,平均为2.81,明显高于纬度较高的东海和黄渤海海域;该海域鱼类可划分为两个群落,即永乐群岛群落(群落I)和宣德群岛群落(群落II)。AnOSIM和rElATE检验表明,两个群落间鱼类组成的差异显著(r=0.685,P=0.029<0.05),且群落格局较为稳定(r=0.958,P=0.003<0.01)。We assessed fish communities using bottom gillnet surveys in 7 coral reefs(Beijiao Reef,Huaguang Reef,Jinyin Island,Dongdao Island,Langhua Reef,Yuzhuo Reef and Yongxing Island) of the Xisha Islands in May,2003 and analyzed species composition and diversity,dominant species,and community pattern using the software Primer.A total of 146 fish species belonging to 31 families and 10 orders were collected during the survey.Fishes in the coral reefs were dominated by the typical tropical species,including members of the families Scaridae,Chaetodontidae and Lutjanidae.According to the Index of Relative Importance(IRI),the six most dominant fish species were Myripristis murdjan,Lutjanus kasmira,Paracaesio sordidus,Caesio diagramma,Axinurus thynnoides and Hexanchus griseus,respectively.Shannon-Wiener diversity indices(H') ranged from 1.91 to 3.33 among reefs,with an average of 2.81.Overall,diversity indices for the Xisha Islands were higher than those found in the East China Sea,the Yellow Sea and the Bohai Sea,all of which are found at a higher latitude.The spatial pattern of fish communities was analyzed using hierarchical clustering and non-metric multidimensional scaling.Two major groups based on fish assemblages were indentified,with group I located in the Yongle Islands and Group II in the Xuande Islands.ANOSIM and RELATE tests showed significant differences(R=0.685,P=0.029<0.05) in fish assemblages between these groups and the community pattern were quite stable(R=0.958,P=0.003<0.01).中央级公益性科研院所基本科研业务费专项(2010YD10、2009TS08);农业部近海渔业资源调查项目(070404

Dynamics of demersal fish species diversity and biomass of dominant species in autumn in the Beibu Gulf,northwestern South China Sea

根据1992年、2001年和2006年秋季在北部湾进行的底拖网调查数据,对该海域鱼类的种类组成、物种多样性、优势种及其数量的变动趋势进行分析。1992年共记录鱼类171种,隶属17目77科;2001年记录鱼类156种,隶属18目71科;2006年记录157种,隶属17目67科。3个年代记录的鱼类均以鲈形目的种类数最多,其中1992年为96种(占56.14%)、2001年90种(占57.69%)和2006年89种(占56.69%)。鱼类的PIElOu均匀度指数(J')和SHAnnOn-WIEnEr多样性指数(H')的变化趋势一致:以2001年最高,为0.72和3.64;其次为1992年,为0.64和3.27;2006年最低,分别为0.52和2.64。丰富度指数(d)呈逐年下降的趋势:为1992年的21.03,2001年的20.74和2006年的19.61。建立非线性回归模型对北部湾3个年代出现的6种共有优势种(发光鲷ACrOPOMA JAPOnICuM、带鱼TrICHIuruS HAuMElA、二长棘鲷PArArgyrOPS EdITA、黄斑鲾lEIOgnATHuS bInduS、竹荚鱼TrACHuruS JAPOnICuS和黄带绯鲤uPEnEuS SulPHurEuS)的数量变化趋势进行分析。结果表明:北部湾鱼类中的经济价值较高的优势种逐渐被低值和小型的鱼类所替代,但繁殖力较强和寿命较短的鱼类变动较小。在6种共同优势种中,黄斑鲾和发光鲷的渔获率呈上升趋势;带鱼和黄带绯鲤的渔获率呈下降趋势;而二长棘鲷和竹荚鱼的渔获率基本保持不变。研究结果表明,北部湾鱼类的优势种更替明显,总体变化趋势是k选择种类(以红笛鲷和黑印真鲨等为代表)逐渐被r选择种类(发光鲷、鲾科和天竺鱼科等为代表)所替代,即寿命长、个体大和营养级高的鱼类数量减少,寿命短、个体小和营养级较低的种类增多。The Beibu Gulf is a semi-enclosed gulf located in the northwestern South China Sea and surrounded by the land territories of China and Vietnam.The region has a tropical to subtropical climate.Thousands of fish and shellfish species have been identified in the Beibu Gulf and support some very important fisheries throughout the year in the region.Large scale resource surveys have been conducted over the last few decades to assess fisheries resources in the Beibu Gulf,and a large quantity of biological and environmental data have been collected.Such scientific data are perfect for evaluating changes in the ecosystem and answers questions such as what changes have occurred over the last few decades to the fisheries ecosystem in the Beibu Gulf? In the study,we analyzed data collected in otter trawl surveys in the Beibu Gulf in autumn 1992,2001 and 2006 to evaluate fish species composition and diversity,dominant species,and their biomasses.The analysis showed that 171 fish species caught in the 1992 autumn survey in the Beibu Gulf Gulf belonged to 77 families and 17 orders,a total of 156 fish species belonging to 71 families and 18 orders were found in the 2001 survey and 157 species belonging to 67 families and 17 orders were identified in 2006.Perciformes had the highest number of fish species,96 species(accounting for 56.14%) in 1992,90 species(57.69%) in 2001 and 89 species(56.69%) in 2006.The Pielou evenness index(J′) had the same temporal trend as the Shannon-Wiener diversity index(H′).Both indices were the highest in 2001,followed by those in 1992 and 2006.The Margalef richness index(D) reduced from 21.03 in 1992 to 20.74 in 2001 and to 19.61 in 2006.Nonlinear regression models were developed to quantify the temporal trends of biomass of the 6 dominant species(Acropoma japonicum,Trichiurus haumela,Parargyrops edita,Leiognathus bindus,Trachurus japonicas and Upeneus sulphureus) in the Beibu Gulf.The dominant species were found to shift from the high-value fish species to the low-value species,but no significant changes for fish species with high reproduction rates and short life spans.The catch rates increased during the survey period for A.japonicum and L.bindus,decreased for T.haumela and U.sulphureus,and remained similar for P.edita and T.japonicus.This study shows an apparent succession of the dominant species with an overall trend of the K-selection species(such as Lutjanus sanguineus and Carcharhinus menisorrah) being replaced by the r-selection species(such as A.japonicum,Leiognathus,and Apogonichthys).The abundance of fish species with long life span,large size and high trophic levels decreased,while short-lived and small-sized fish species in low trophic levels increased their abundance over the time period covered by the survey.The study provides important evidence of changes occurring in the Beibu Gulf ecosystem.农业部近海渔业资源调查项目(070404);中央级公益性科研院所基本科研业务费专项(2007TS08;2007ZD08;2009TS08;2010YD10);广东省海洋渔业资源综合评价(GD908-02-05

Variations of fish species diversity,faunal assemblage,and abundances in Daya Bay in 1980-2007.

根据2004—2005年大亚湾海域底拖网鱼类调查数据,并结合1980—2007年的历史资料,分析了该海域鱼类的种类组成、区系特征、多样性、优势种和数量变化趋势.结果表明:2004—2005年,大亚湾海域共记录鱼类107种,分属13目50科,以中下层鱼类的种类最多,为48种,其次是中上层和底层种类,分别为37种和21种.大亚湾鱼类区系具热带和亚热带特性,以暖水性种类占绝对优势,为97种,暖温性种类为10种.多样性指数以夏季最高(3.82),其次是冬季(3.37)和秋季(3.00),春季最低(2.40).PIElOu均匀度指数的季节变化情况与多样性指数相似.1980—2007年大亚湾海域鱼类群落特征发生了明显的变化:鱼类种类数减少,优势种更替明显.鱼类种类数由1980年的157种减少至1990年的110种,2004—2005年继续减少至107种;鱼类优势种由1980年以带鱼和银鲳等优质鱼为主,更替为以小型和低值的小沙丁鱼、小公鱼和二长棘鲷幼鱼为主.用包含年际变化趋势和季节性周期变化的回归模型模拟1980—2007大亚湾鱼类资源密度的变化,鱼类资源密度在1980—1999年和1990—2007年两个时期均呈下降趋势,但1990—2007年间下降幅度比1980—1999年间大;1980—1999年鱼类资源密度的季节波动幅度较平缓(振幅为0.099),而1990—2007年的季节波动较大(振幅为0.420),说明1990—2007年阶段大亚湾鱼类数量的季节变化更为显著.Based on the 2004-2005 otter trawl survey data and the 1980-2007 relevant historical records,this paper analyzed the variations of fish species composition,faunal assemblage,diversity indices,dominant species,and abundance in Daya Bay.In the 2004-2005 trawl survey,a total of 107 fish species were recorded,belonging to 50 families and 13 orders,among which,meso-demersal fish were predominant,with 48 species recorded,and followed by pelagic and demersal fishes,with 37 and 21 species,respectively.The fishes in the Bay belonged to tropical and subtropical fauna,with the dominance of warm water fishes(97 species) and warm-temperate water fishes(10 species).The diversity index was the highest in summer(3.82),followed by in winter(3.37) and autumn(3.00),and the lowest in spring(2.40).The seasonal variation of Pielou evenness index mimicked that of diversity index.In 1980-2007,the characteristics of fish community in the Bay changed obviously.The species number reduced from 157 species in the 1980s to 110 species in the 1990s and to 107 species in 2004-2005,and the dominant species shifted from the high-value fishes such as hairtail and pomfret in the 1980s to low-value fishes such as sardine fish,anchovy,and juvenile porgy.A non-linear regression model composed of inter-annual trend and seasonal cycle was used to simulate the changes of fish stock density in 1980-1999 and 1990-2007,and the results indicated that in the two periods,the fish stock density in the Bay all showed a decreasing trend,but the decrement was larger in 1990-2007 than in 1980-1999.The seasonal variation of the stock density in 1980-1999 was relatively small,with an amplitude being 0.099,while that in 1990-2007 was relatively larger,with the amplitude being 0.420,illustrating that the fish abundance in the Bay had a larger seasonal fluctuation in 1990-2007.中央级公益性科研院所基本科研业务专项(2010YD10、2009TS08)资

Fish species composition and community pattern in the continental shelf of northwestern South China Sea

根据2006—2007年在南海西北部陆架区海域进行的4航次底拖网调查数据,对该海域鱼类的种类组成和群落格局进行分析。调查共采获鱼类262种,隶属于20目102科。以冬季出现种类数最多,为166种;夏季和秋季次之,分别为161种和155种;春季最少,为135种。运用聚类分析和非度量多维标度(nMdS)方法分析了南海西北部陆架区鱼类群落结构的空间分布。研究表明,该海域鱼类可划分为5个群落,分别为粤西沿岸群落(群落Ⅰ)、海南岛东南沿岸群落(群落Ⅱ)、海南岛东部深海群落(群落Ⅲ)、过渡群落(群落Ⅳ)和混合群落(群落V)。AnOSIM检验表明,各群落间鱼类组成的差异极为显著(r=0.847-0.939,P<0.001)。鱼类群落格局的变化与海流和水深关系密切,有较明显的沿水深梯度分布的规律。咸淡水鱼类在雷州半岛东部的冷涡区域,形成群落Ⅰ;南海暖流控制区域内的深海鱼类,形成群落Ⅲ;在南海暖流最为强劲的冬季,研究区域内大部分鱼类集结为混合性群落V;琼东南沿岸的上升流区内形成群落Ⅱ;沿岸流强劲的夏、秋季,在沿岸流和上升流交汇处,形成过渡性群落Ⅳ。To understand fish species composition,community pattern,dominant species and seasonal variation in the continental shelf of northwestern South China Sea,four otter trawl surveys were conducted in January and August 2006,and April and November 2007,representing winter,summer,spring and autumn,respectively.Sixteen stations were assigned in each otter trawl survey along the coastlines from eastern Leizhou Peninsula to southeastern Hainan Island.Fish collection and data analysis followed the National Marine Survey Standards(GB/T12763.6—2007).Totally 262 fish species,from 102 families and 20 orders,were collected in the four seasonal surveys.The results revealed that the highest species diversity was in winter with 166 species recorded and the lowest was in spring with 135 species recorded;161 and 155 species were recorded in summer and autumn,respectively.The Order Perciformes was the most important fish group in the continental shelf of northwestern South China Sea;the highest species diversity recorded was the Perciformes in all four seasons,and 40 out of 72 species recorded year-round belonged to the Perciformes.Species found in all four seasons contributed to 80.34% of total fish biomass.Ninety-one species found only in a single season contributed to 1.62% of total fish biomass.The spatial pattern of fish communities was analyzed using the hierarchical clustering and non-metric multi-dimensional scaling(NMDS),five fish groups were indentified.The Group Ⅰ,recorded in all four seasons,was located in the coastal waters of western Guangdong Province and consisted of 3 or 4 stations.The scale and the distribution area of the Group Ⅰ were stable among seasons.The Group Ⅱ,recorded in spring,summer and autumn,was located in the coastal waters of southeastern Hainan Island and consisted of 6—9 stations.The scale and the distribution area of the Group Ⅱ had seasonal variation.The Group Ⅲ,recorded in spring,summer and autumn,was located in the deep waters of eastern Hainan Island and consisted of 4 stations.The scale and the distribution area of the Group Ⅲ were stable.The Group Ⅳ as a transitional community,recorded in summer and autumn only,was located in the deep waters of eastern Hainan Island and consisted of 1—3 stations.The scale and the distribution area of the Group Ⅳ were small and changed largely with season.The Group Ⅴ as a mixed community,recorded in winter only,was also located in the deep waters of eastern Hainan Island and consisted of 13 stations.The scale and the distribution area of the Group Ⅴ were the largest among the 5 groups.Based on the analysis of similarities(ANOSIM),the results showed the significant differences(R=0.847-0.939,P <0.001) in fish community pattern for all four seasons.Although the station combinations in each fish community had seasonal variation,the correlation coefficients on the community similarities between spring and summer,between summer and autumn and between autumn and winter were 0.780,0.630 and 0.777,respectively.The variations of fish community pattern are closely related to ocean currents and depth.The brackish fishes distributed in the cold eddy area of eastern Leizhou Peninsula and contributed to the Group Ⅰ.The deep sea fishes along the South China Sea Warm Current in eastern Hainan Island contributed to the Group Ⅲ.In winter with the strongest South China Sea Warm Current recorded in the deep waters of eastern Hainan Island,the area was dominated by fishes from the mixed Group Ⅴ.Because of the upwelling in the coastal waters of southeastern Hainan Island the area was dominated by fishes from the Group Ⅱ.In summer and autumn,the coastal current was strong and mixed with the upwelling in the deep waters of eastern Hainan Island;therefore,the area was dominated by fishes from the transitional Group Ⅳ.This study provides scientific evidences for further sustainable fisheries development and conservation in the continental shelf of northwestern South China Sea.我国近海海洋综合调查与评价专项(908-01-ST08); 中央级公益性科研院所基本科研业务费专项资金(中国水产科学研究院南海水产研究所)资助项目(2009TS08;2010YD01和2010YD10); 农业部近海渔业资源调查项目(070404); 海洋公益性行业科研专项(201005012); 广东省海洋渔业资源综合评价资助项目(GD908-02-05

类泛素蛋白及其中文命名

泛素家族包括泛素及类泛素蛋白,约20种成员蛋白.近年来,泛素家族领域取得了迅猛发展,并已与生物学及医学研究的各个领域相互交叉.泛素家族介导的蛋白质降解和细胞自噬机制的发现分别于2004和2016年获得诺贝尔奖.但是,类泛素蛋白并没有统一规范的中文译名. 2018年4月9日在苏州召开的《泛素家族介导的蛋白质降解和细胞自噬》专著的编委会上,部分作者讨论了类泛素蛋白的中文命名问题,并在随后的\"泛素家族、自噬与疾病\"(Ubiquitinfamily,autophagy anddiseases)苏州会议上提出了类泛素蛋白中文翻译草案,此草案在参加该会议的国内学者及海外华人学者间取得了高度共识.冷泉港亚洲\"泛素家族、自噬与疾病\"苏州会议是由美国冷泉港实验室主办、两年一度、面向全球的英文会议.该会议在海内外华人学者中具有广泛影响,因此,参会华人学者的意见具有一定的代表性.本文介绍了10个类别的类泛素蛋白的中文命名,系统总结了它们的结构特点,并比较了参与各种类泛素化修饰的酶和它们的生物学功能.文章由45名从事该领域研究的专家合作撰写,其中包括中国工程院院士1名,相关学者4名,长江学者3名,国家杰出青年科学基金获得者18名和美国知名高校华人教授4名.他们绝大多数是参加编写即将由科学出版社出版的专著《泛素家族介导的蛋白质降解和细胞自噬》的专家

Spatio-temporal variability of fish diversity and dominant species in the Beibu Gulf

根据2007年在北部湾进行的4季渔业资源底拖网调查资料,对该海域鱼类的种类组成、物种多样性和优势种的时空变化进行分析。本次调查共捕获鱼类323种,隶属于18目101科,以发光鲷(ACrOPOMA JAPOnICuM)、黄斑鲾(lEIOgnATHuS bInduS)、竹鱼(TrACHuruS JAPOnICuS)、二长棘鲷(PArArgyrOPS EdITA)和大头白姑鱼(ArgyrOSOMuS MACrOCEPHAluS)为主要优势种。分析结果表明,北部湾鱼类的优势种更替明显,总体趋势为k选择种类(以红笛鲷和黑印真鲨等为代表)被r选择种类(发光鲷、鲾科和天竺鱼科等为代表)所替代,即寿命长、个体大和营养级高的鱼类种类减少,寿命短、个体小和营养级较低的种类增多。鱼类的SHAnnOn-WIEnEr多样性指数(H’)以共同渔区北部海域最高(3.60),东北部海域次之(3.58),共同渔区南部海域最低(2.35),四季多样性指数为2.96~3.77,平均3.31。2007年多样性指数比1992-1993年低,但高于1998-1999年,表明近年来该海域捕捞压力有所减缓,使得渔业资源有一定的恢复。本研究旨在了解北部湾生物多样性和优势种的动态变化及演替状况,为该海域渔业资源的合理开发与可持续利用对策提供科学依据。Based on data collected by quarterly otter trawl surveys in the Beibu Gulf in 2007,the species composition,diversity and dominant species of fishes were analyzed.A total number of 323 fish species belonging to 101 families and 18 orders were collected.The dominant species were Acropoma japonicum,Leiognathus bindus,Trachurus japonicus,Parargyrops edita and Argyrosomus macrocephalus.Data analysis shows an apparent succession of the dominant species with an overall trend of the k-selection species (such as Lutjanus sanguineus and Carcharhinus menisorrah) being replaced by r-selection species (such as Acropoma japonicum,Leiognathus,and Apogonichthys).The abundances of long-lived,large-size,and high trophic level fishes decrease,while those of the short-lived,small-size,and low trophic level increase.The Shannon-Wiener diversity index (H') in the northern common fishing zone (3.60) was the highest,followed by that of the northeast Beibu Gulf (3.58),and the lowest (2.35) appeared in southern common fishing zone..The seasonal variation of the diversity index ranged from 2.96 to 3.77 with an average of 3.31.The diversity index was lower in 2007 than that in 1992-1993,but higher than that in 1998 1999.This indicates that fishing intensity has alleviated in the recent years and has resulted in recovery of the fishery resources.农业部近海渔业资源调查项目(070404);中央级公益性科研院所基本科研业务费专项资金(中国水产科学研究院南海水产研究所)项目(2007TS08;2009TS08;2010YD10);我国近海海洋综合调查与评价专项(908-01-ST09);广东省海洋渔业资源综合评价项目(GD908-02-05

Fish community pattern and its relation to environmental factors in the Beibu Gulf

根据2007年在北部湾海域进行的4航次底拖网调查数据,对北部湾鱼类的种类组成和群落格局进行分析。该调查共采获鱼类323种,隶属于18目101科。以冬季出现种类数最多,为231种;秋季和夏季次之,分别为217种和214种;春季最少,为186种。运用聚类分析和非度量多维标度(nMdS)方法分析了北部湾鱼类群落结构的空间分布,研究表明,该海域鱼类可划分为5个群落,为较为稳定的东北部沿岸群落(群落Ⅰ)、海南岛西岸群落(群落Ⅱ)、北部湾中南部群落(群落Ⅲ)、白龙尾岛附近海域群落(群落Ⅳ)和季节波动较大的琼州海峡西侧群落(群落V)。AnOSIn检验表明,各群落间鱼类组成的差异极为显著(r=0.896~0.956,P<0.001)。对不同季节鱼类群落格局与环境因子(水深、底层水温、底层盐度)的相关性分析表明,鱼类群落组成的变化与水深的相关性最好(春季r=0.491,夏季r=0.578,秋季r=0.594,冬季r=0.514),与温度和盐度的相关性较差。Based on data collected by quarterly otter trawl surveys in the Beibu Gulf in 2007,fish species compositions and community pattern were analyzed.A total number of 323 fish species belonging to 101 families and 18 orders were collected during the surveys.The largest number of species was recorded in winter(231 species),followed by those in autumn and summer(217 and 214 species,respectively),and the number of fish species was the smallest in spring(186 species).The spatial pattern of fish community was analyzed using hierarchical clustering and non-metric multidimensional scaling.Five station groups based on fish assemblages were indentified.The Group Ⅰ was located in the coastal waters of northeast Beibu Gulf and showed less seasonal variation in distribution.The Group Ⅱ was located in the coastal waters west off Hainan Island.The Group Ⅲ covered a large area of the central and southern waters of the Beibu Gulf,while the Group Ⅳ located near the Bailongwei Island covered the least stations,and the Group Ⅴ can only be identified in spring season to the west Qiongzhou Strait.The ANOSIN tests showed highly significant differences(R=0.896-0.956,P<0.001)in fish assemblages between the station groups.The relationships between changes in fish community pattern and environmental factors(depth,bottom temperature and bottom salinity)were examined.The correlation analysis showed that the water depth was the major environmental factor dominating the fish community pattern,while bottom temperature and salinity contributed less to determining the community pattern.中央级公益性科研院所基本科研业务费专项(2010YD10、2009TS08);农业部近海渔业资源调查项目(070404);我国近海海洋综合调查与评价专项(908-01-ST09);广东省“九○八”专项(GD9080205