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1.
长江口潮下带大型底栖动物群落特征 总被引：1，自引：0，他引：1
2013年至2014年,对长江口及其邻近水域进行了8个航次104个站点的潮下带大型底栖动物调查,通过Shannon-Wiener多样性指数(H)、Pielou种类均匀度(E)、种类丰度(D)和优势度指数(Y)等指标参数分析了大型底栖动物的物种多样性,应用等级聚类和非度量多维标度排序分析了底栖动物群落结构。结果显示,2013年共采获大型底栖动物49种,2014年40种,每年不同季节种类更替明显。2013年大型底栖动物丰度和生物量最高分别出现在春季和秋季,2014年分别为冬季和夏季,不同年份不同季节的生物量和丰度明显不同。不同年份的特征种均以甲壳动物类群为主,鱼类优势种增多。2013年秋季和2014年春季的大型底栖动物相对于同年度其他季节有更高的多样性,年度变化上多样性指数整体增高。群落结构分析表明,2013年夏秋冬聚为1组,春季为1组;2014年春夏秋聚为1组,冬季为1组。ABC曲线结果显示,潮下带大型底栖动物群落在2013年四季受到中度干扰,2014年春夏秋受干扰不明显,冬季受到中等程度以上的干扰。本研究结果为长江口生态环境保护及修复提供了理论依据。 相似文献
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长江口九段沙潮间带大型底栖动物季节分布特征的初步研究 总被引：11，自引：1，他引：11
2005年4月(春季)、7月(夏季)、10月(秋季)和2006年1月(冬季).对长江口九段沙潮间带大型底栖动物进行了定性和定量调查.共采集到大型底栖动物73种,平均丰度442.94 ind·m-2,生物量40.78 g·m-2.与历史资料比对,大型底栖动物的种数显著增加,新记录31种,曾经有过报道但未采集到标本的有3种;大型底栖动物的丰度变化不大,生物量有明显增加,多样性指数增大.大型底栖动物的丰度、生物量、多样性指数和相对重要性指数随季节的不同而有所变化,其中丰度和生物量以秋季最高,夏季次之,春季和冬季较低;多样性指数冬季最高,夏季次之,春季和秋季较低.优势种为谭氏泥蟹、梨形环棱螺、绯拟沼螺、琵琶拟沼螺、河蚬、焦河篮蛤、中国绿螂和丝异蚓虫;相对重要性指数值较高的有无齿相手蟹、天津厚蟹、谭氏泥蟹、中华拟蟹守螺、堇拟沼螺、绯拟沼螺、琵琶拟沼螺、梨形环棱螺、中国绿螂、焦河篮蛤、河蚬和丝异蚓虫.大型底栖动物的分布主要受水温、水文和工程的影响,此外,工程建设和互花米草扩散对其也造成了一定的影响. 相似文献
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洋山深水港海域大型底栖动物初步研究 总被引：1，自引：0，他引：1
2003~2005年每年2月、5月和8月按《海洋监测规范》中大型底栖动物调查方法,分别对洋山深水港一期工程施工海域(30°30′~30°54′N、121°45′~122°30′E)20个取样点进行了大型底栖动物调查。根据调查结果,分析与讨论该海域底栖动物的种类组成、生物量、栖息密度和群落多样性的分布与变化。监测结果显示:一期工程施工期,底栖动物的种类数逐年减少,2003~2005年种类数分别为21种、17种和16种;底栖动物栖息密度逐年下降,2003年(31.10 ind/m2)>2004年(12.50 ind/m2)>2005年(11.00 ind/m2);底栖动物平均总生物量总体表现为逐年降低,2003年(4.26 g/m2)>2005年(2.18 g/m2)>2004年(0.62 g/m2),2004年生物量下降尤为显著,2005年生物量略有回升;生物多样性指数也逐年降低,2003~2005年分别为0.81、0.36和0.16。三年监测结果表明,洋山深水港一期工程海域施工期底栖动物种类数、总生物量、栖息密度以及多样性指数总体呈逐年下降趋势,群落结构趋于简单化,说明工程海域施工期对大型底栖动物产生了一定程度的影响。 相似文献
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长江口九段沙潮间带大型底栖动物季节分布特征的初步研究 总被引：1，自引：0，他引：1
2005年4月（春季）、7月（夏季）、10月（秋季）和2006年1月（冬季）。对长江口九段沙潮间带大型底栖动物进行了定性和定量调查。共采集到大型底栖动物73种，平均丰度442．94ind·m^-2，生物量40．78g·m^-2．与历史资料比对，大型底栖动物的种数显著增加，新记录31种，曾经有过报道但未采集到标本的有3种；大型底栖动物的丰度变化不大，生物量有明显增加，多样性指数增大。大型底栖动物的丰度、生物量、多样性指数和相对重要性指数随季节的不同而有所变化，其中丰度和生物量以秋季最高，夏季次之，春季和冬季较低；多样性指数冬季最高，夏季次之，春季和秋季较低。优势种为谭氏泥蟹、梨形环棱螺、绯拟沼螺、琵琶拟沼螺、河蚬、焦河篮蛤、中国绿螂和丝异蚓虫；相对重要性指数值较高的有无齿相手蟹、天津厚蟹、谭氏泥蟹、中华拟蟹守螺、堇拟沼螺、绯拟沼螺、琵琶拟沼螺、梨形环棱螺、中国绿螂、焦河篮蛤、河蚬和丝异蚓虫。大型底栖动物的分布主要受水温、水文和工程的影响，此外，工程建设和互花米草扩散对其也造成了一定的影响。 相似文献
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在罗源湾全面网箱退养前后(2010—2017年)共进行了6个航次的夏季大型底栖动物调查,共鉴定大型底栖动物156种,其中多毛类71种,甲壳动物37种,软体动物20种,棘皮动物10种,其它类动物18种。生物群落结构的年际变化与全面退养行为呈明显的相关性。退养前(2010—2013年)种类数年际变化呈现显著下降的趋势,实施海域退养整治后(2016—2017年)年种数明显回升;年度总丰度和总生物量呈现以退养前后为返转的显著年际上升再回落的趋势,优势类群多毛类的年际变化趋势与此相同,而主要类群软体动物的变化趋势与此相反;总体上三项多样性指数都呈现以退养前后为拐点的逐渐降低再回升趋稳的大致变动过程,多样性变动与退养整治前后环境的转变明显关联。ABC曲线应用分析表明退养前底栖动物群落受到中度的污染扰动,退养后群落未受污染扰动;罗源湾底栖动物群落结构变化对海域退养行为的响应明显。 相似文献
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根据 2010─2019年夏季底拖网调查资料, 对莱州湾蟹类群落结构特征年际变化及其影响因子进行相关研究, 包括群落的种类组成、优势种、物种多样性和群落聚类分析等, 运用冗余分析分析影响蟹类群落年际变化的环境因子。结果表明: 2010─2019 年夏季共捕获蟹类 16 种, 蟹类种数年间波动较大, 减少趋势明显, 2011 年种类数最多, 为 14 种, 2017 年最少, 为 7 种, 优势种每年 2~4 种。生物量和尾数呈先减少后增加的变化趋势, 多样性指数在 2014─ 2015 年明显下降。10 年间蟹类群落共分为 4 组, 组 A 为 2010 年, 组 B 为 2011 年、2014 年和 2015 年, 组 C 为 2012 年、 2013 年、2018 年和 2019 年, 组 D 为 2016 年和 2017 年。PERMANOVA 分析结果显示, 各组间差异显著(P＜0.01)。 SIMPER 分析表明, 各组特征种为日本蟳(Charybdis japonica)、三疣梭子蟹(Portunus trituberculatus)和隆线强蟹 (Eucrate crenata)等, 分歧种主要为日本关公蟹(Dorippe japonica)、日本蟳、绒毛近方蟹(Hemigrapsus penicillatus) 和隆线强蟹等。冗余分析表明, 对蟹类群落年际变化影响较大的因子是底层叶绿素、底栖生物生物量和厄尔尼诺指数。本研究通过对蟹类群落年间动态变化的调查, 旨在为三疣梭子蟹增殖放流工作提供科学依据。 相似文献
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基于2015年9月和2016年5月采集的曹妃甸近岸海域的大型底栖动物数据,对该海域大型底栖动物的种类组成和群落结构等进行研究,利用丰度/生物量比较曲线法、AMBI指数法和M-AMBI指数法对研究海域大型底栖动物群落健康和生境质量进行评价。研究结果表明,2015年9月和2016年5月共采集到大型底栖动物73种,其中节肢动物和环节动物物种数占据较大比例。该海域的优势种为日本大螯蜚、日本刺沙蚕、囊叶齿吻沙蚕、轮双眼钩虾,其中日本大螯蜚具有最大的丰度和优势度。群落结构聚类分析和多维尺度分析表明,2015年9月研究区域的大型底栖动物群落以20%的相似性可以分为4组,2016年5月以10%的相似性可以分为7组,两次调查的群落结构相似性均较低。丰度/生物量比较曲线法研究结果显示,2015年9月底栖群落受到严重污染扰动,而到2016年5月,底栖动物群落生物量优势显著上升,群落受扰动状况改善,达到未受或受到轻微污染扰动状态。AMBI指数及M-AMBI指数法评价结果表明,曹妃甸海域大部分站位生境质量为良好状态。本研究揭示了曹妃甸近岸海域大型底栖动物群落结构特征,可为该海域生态环境保护提供依据。 相似文献
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2013年5月(春季)、8月(夏季)、11月(秋季),对江苏中南部潮间带大型底栖动物进行了定性和定量调查。共采集到大型底栖动物68种,定量63种,定性19种,多毛类、软体动物以及甲壳动物是组成大型底栖动物的主要类群。优势种为文蛤(Meretrix meretrix)、泥螺(Bullacta exarata)、四角蛤蜊(Mactra veneriformis)、托氏虫昌螺(Umbonium thomasi)、加州齿吻沙蚕(Nephtys californiensis)、双齿围沙蚕(Nereis aibuhitensis)以及宽身大眼蟹(Macrophthalumus dilatatus)等。年平均总生物密度65.15 ind·m-2,平均总生物量94.21g·m-2。和历史资料比较后发现,自20世纪80年代至今,江苏中南部潮间带大型底栖动物生物量有增无减。大型底栖动物的生物密度、生物量、多样性和相对重要性指数随季节的不同而有所变化,其中生物密度、生物量以及多样性指数均以春季最高。江苏中南部潮间带大型底栖动物群落生物量优势度曲线位于丰度曲线上方,群落结构稳定性较高,未出现明显扰动。 相似文献
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2006年8月在山东南部沿岸海域32个站位进行了大型底栖动物研究,共发现大型底栖动物182种,其中,多毛类92种,甲壳类42种,软体动物29种,棘皮动物9种,其他类群10种。研究海域大型底栖动物总平均丰度为2001 ind./m~2,总平均生物量为15.92 g/m~2。根据IRI指数,优势种前4种分别是寡鳃齿吻沙蚕(Nephtys oligobranchia)、中蚓虫(Mediomastus sp.)、独指虫(Aricidea fragilis)和巴氏钩毛虫(Sigambra bassi)。Shannon-Wiener多样性指数(H￠)为2.20~4.59,平均值为3.92;Margalef丰富度指数(d)为0.99~5.39,平均值为3.98;Pielou均匀度指数(J)为0.61~0.89,平均值为0.80。根据CLUSTER分析结果,在36%的相似性水平上可将研究站位划分为2个群落。多样性分析表明,研究海域底栖生态环境总体为清洁。Pearson相关性分析显示,大型底栖动物丰度和水深呈显著负相关(r=-0.38,P0.05)。BIOENV分析表明,与群落结构关系最密切的环境因子组合是粉砂+水深+有机碳(r=0.46)。 相似文献
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渔山列岛潮间带大型底栖动物群落结构 总被引：1，自引：0，他引：1
于2009年3月的大潮期间对渔山列岛潮间带布设5个断面,进行大型底栖动物调查。结果表明,该海域潮间带采集到大型底栖动物90种,其中腔肠动物3种,多毛类11种,软体动物45种,甲壳类19种,棘皮动物6种,其它6种。潮间带大型底栖动物总平均生物量5307.06g/m2,总平均丰度为2323.20ind/m2。在各类群底栖动物中,软体动物的平均生物量及丰度居首位。渔山列岛潮间带大型底栖动物的Shannon-Wiener多样性指数(H’)、Simpson多样性指数(D)、Mangalef丰富度指数(d)和Pielou均匀度指数(J)分别为1.421～2.417、0.497～0.624、1.396～3.223和0.484～0.648,平均值为2.052、0.577、2.477和0.590。大型底栖动物ABC曲线分析表明,底栖动物群落无干扰或轻度干扰。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
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In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 相似文献
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Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
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Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
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