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Pmpusndnorliuetlisp.nov.(Fig.1)StroInateOdeampas,Cheng,l962,Fish.SouthChinaSea,761-762,fig.6l6(ZhaPO,GuanghallLangzhou,Shanwi,Nanao,GUangdongProvince).Inagnosis:Standrilengthofadultshort,notmorethanl5omm.Thehalbenl-shaPedspinesofdOhalandanalfinsareconspicuousinbOthjuvenileandadultfishandnoteInbeddedinskin.Eyeslmp,eyediameter2.8-3.5inheadlength.PamPhenoidofskullroundcurve-shaped,orbitalfossalarge,sedri-circularshaPed-Otoliththickandsolid,itsanteriornotchshallow-NuInberofprecaudaland…  相似文献   

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通过对东海区鲳鱼近年群体组成变化及银鲳生物学特性变化来分析目前鲳鱼资源利用状况,结果表明:一方面,虽然近年鲳鱼产量大幅增加,但其平均体重、优势叉长组成及年龄组成均出现明显下降,资源状况日益恶化;另一方面,1龄鱼已占渔获的93.68%,目前捕捞现行点开捕年龄tc=1和捕捞死亡系数F=2.51,单位补充量繁殖力相对百分比P<1.9%,单位补充量渔获量(Yw/R)为70g/尾,均显示已处于严重的生物学型捕捞过度.建议渔业管理部门大力削减作业渔船约50%,严格控制捕捞强度,逐步推迟开捕年龄至3龄以上,使鲳鱼资源真正能够永续利用。  相似文献   

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研究了盐度对黄鳍鲷SparuslatusHouttuyn、平鲷Rhabdosargussarba(Forskal)、黑鲷Sparusmacrocephalus(Basilewsky)和真鲷Pagrsomusmajor(TemmincketSchlegel)4种鲷鱼精子活力的影响。对南海区4种鲷鱼精子的适盐性及其活力进行了比较,黄鳍鲷、平鲷、黑鲷和真鲷精子激活所需的最低盐度分别为8、10、>8、>10;激活的最适盐度则分别为21、22、25、25,与之相应的精子活动(涡动)时间分别为14.7、17.7、17.2、18.0min;在高盐条件(盐度40左右)下,黄鳍鲷精子的适应性最强,精子活力最好,其次是黑鲷、真鲷的精子,平鲷精子对高盐条件的适应性最差。  相似文献   

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用不同 pH 的海水对真鲷(Pagrosom us m ajor)、平鲷(Rhabdosargus sarba)、黑鲷(Sparusm acrocephalus)和黄鳍鲷(S.latus)精子进行激活实验。结果表明,四种鲷鱼精子对pH 的适应范围较广,其最适pH 值与其生态习性相关。  相似文献   

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Selection of diet for culture of juvenile silver pomfret, Pampus argenteus   总被引:2,自引:0,他引:2  
Juvenile silver pomfret, Pampus argenteus, was grown in culture tanks for 9 weeks on four different diets, and their effects on fish growth, digestive enzyme activity, and body composition were assessed. The feeding regime was as follows: Diet 1: fish meat; Diet 2: fish meat+artificial feed; Diet 3: fish meat+artificial feed+Agamaki clam meat; Diet 4: fish meat+artificial feed+Agamaki clam+copepods. The greatest weight gain was associated with Diet 4, while the lowest weight gain was associated with Diet 1. No significant difference was observed in weight gain between fish receiving Diet 2 and Diet 3. Specific growth rate followed similar trends as weight gain. The feed conversion ratio (FCR) of fish fed Diet 1 was significantly higher than the other fish groups, but no significant differences were observed in FCRs of fish fed Diet 2, Diet 3 or Diet 4. There was also no significant difference in the hepatosomatic index (HSI) between the four diets. For fish that received Diets 2-4, containing artificial feed, higher protease activities were detected. A higher lipid content of the experimental diets also significantly increased lipase activities and body lipid content. No significant differences in amylase activity or body protein content were found between Diets 1-4. In conclusion, a variety of food components, including copepods and artificial feed, in the diet of silver pomfret significantly increased digestive enzyme activity and could improve growth performance.  相似文献   

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ImOUocrON0verevoluti0narytirne,intetspeCiliccomPctitioncanresultincharactedisplacementSthatfadiitateresourcepartitioningamongspedesffeper,l985,Wilirarnanayake,l99O).Fisharenotablyopportunisticintheirfeding,toknowWhereandhowtheybowilloftenprovidemoreinsightintotheirerelogythansbolyknowingtheactUalcomPonentSoftheirdiet(Motta,l988,HUmPhrieS,l993).ArmrdinglymorphologicalcomParisonsamongcoxiccutwspchprovidemportantinfonnationnotonlytosySteInatistsfaedwithtaxonondcprobbo,butaIsot0erelogistS…  相似文献   

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Thirty-two 63.0–134.4 mm standard length specimens collected during 1954–1990 from the coastal waters of the South China Sea and the continental coast of the Taiwan Strait were identified as a new species,Pampus minor Liuet Li, sp. nov. Contribution No. 3329 from the Institute of Oceanology, Chinese Academy of Sciences. Study supported by Chinese Academy of Sciences Special Grant for Biota Research.  相似文献   

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对应用荧光分光光度法测定海洋生物中还原型谷胱甘肽(GSH)含量的方法进行了研究,并测定了分属于鱼、虾、贝、藻的10种海洋生物中谷胱甘肽的含量。利用邻苯二甲醛与GSH反应构成的荧光体系,在激发波长为365nm,发射波长为425nm的条件下,方法的回收率为99.22%~99.69%,变异系数为2.16%。应用此方法测得10种海洋生物中谷胱甘肽的含量为:红笛鲷(Lutjanussanguineus)0.399mg/g,银鲳(Pampusargenteus)0.352mg/g,大海鲢(Megalopscyrinoides)0.561mg/g,尖紫蛤(Sanguinolariaacuta)0.289mg/g,菲律宾蛤仔(Ruditapesphilippinarun)0.287mg/g,墨吉对虾(Penaeusmerguiensis)0.892mg/g,凡纳滨对虾(Litopenaeusvannamei)1.434mg/g,囊藻(Colpomeniasinu-ose)0.221mg/g,石莼(Ulvalactucal)0.727mg/g,马尾藻(Sargassummuticum)0.137mg/g。  相似文献   

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This study was carried out to investigate the biogenic amines(BAs), physicochemical property and microorganisms in dry salted fish, a traditional aquatic food consumed in China. Forty three samples of dry salted fish were gathered from retail and wholesale markets and manufacturers, which had been produced in various regions in China. Cadaverine(CAD) and putrescine(PUT) were quantitatively the most common biogenic amines. About 14% of the samples exceeded the histamine content standards established by the FDA and/or EU. The highest histamine content was found in Silver pomfret(Pampus argenteus)(347.79 mg kg-1). Five of forty three samples exceeded the acceptable content of TYR(100 mg kg-1), and 23.26% of dried-salted fish contained high contents of biogenic amines(above 600 mg kg-1). In addition, species, regions, pickling processes and drying methods made the physicochemical property, microorganisms and biogenic amines in dry salted fish to be different to some extents. The total plate count(TPC) was much higher than that of total halophilic bacteria in all samples. The biogenic amines, physicochemical property and microbiological counts exhibited large variations among samples. Furthermore, no significant correlation between biogenic amines and physicochemical property and TPC was observed. This study indicated that dry salted fish may still present healthy risk for BAs, depending on the processing methods, storage conditions among others.  相似文献   

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辽宁地区木化石丰富,现已发现早侏罗世松柏类硅化木材 5属 8种,其中包括 2个新种, 2个修订种, 3个已知种及 1个未定种,即: Protophyllocladoxylon chaoyangense Zhang et Zheng sp. nov.,P. franconicum Vogellehner, Protosciadopityoxylon liaoxiense Zhang et Zheng sp. nov., P. jeholense (Ogura) Zhang et Zheng comb. nov., Sciadopityoxylon heizyoense(Shimakura) Zhang et Zheng comb. nov., Protocedroxylon dibneri (Shilkina) Shilkina et Chudajb., Xenoxylon latiporosum Gothan, X.? sp.。本文对新种作了描述,对前人鉴定有误的属种进行了修订,并概述了 5个产地木材化石组合特征及其古气候环境。  相似文献   

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Palynological study of the Minato Formation, Noda Group, distributed in the vicinity of Kuji City, Iwate Prefecture, Japan is discussed in this paper. Biostratigraphically important palynomorphs including four angiosperm species, Triprojectus subspinulosus(Funkhouser) Braman, Triprojectus cf. spinulosus(Mtchedlishvili) Stanley, Paraalnipollenites confusus Hills et Wallace and Pistillipollenites macgregorii Rouse, and one fungi species, Pesavis tagluensis Elsik et Jansonius are described. Palyno-assembleges from the lower and the middle horizons of the Minato Formation are considered to indicate Danian in age, which corresponds well with the known fission-track dating. Palyno-assembleges from the lower and middle horizons of the Minato Formations are correlative with those from the Wuyun Formation and the Upper Tsagayan Subformation of Heilongjiang(Amur) River area in northeast China and the Russian Far East. Despite the similarity of the palyno-assembleges, differences in the diversity of angiosperms and species composition of some biostratigraphically important species are recognized between the two regions.  相似文献   

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Guo  Enmian  Liu  Yuan  Liu  Jing  Cui  Zhaoxia 《中国海洋湖沼学报》2010,28(6):1266-1274
Although Pampus minor has been classified as a new species, it still remains controversial. Was used a DNA barcoding technique based on homologous sequence analysis of the16S and COI genes to clarify the confusion over the identification of this species. Among 12 individuals whose genetic distance was 0.002, two haplotypes were found. According to the 16S sequences, the genetic distances ranged from 0.121 to 0.133 between P. minor and other Pampus species. Although the same the genetic distance between the two P. minor haplotypes was generated using COI sequences, the haplotype of Pm22-23, Pm28, and Pm32-33 was the same as that of Pci EF607462 and EF607466, while the haplotype of Pm24-27 and Pm29-31 was the same as that of Pci EF607461 and EF607463-65. In addition, the genetic distance ranged only from 0.002 to 0.005 between P. minor and Pa EF607460 and EF607458. Apart from this, the interspecies genetic distances varied from 0.135 to 0.143 between P. minor and other Pampus species according to the COI sequences. Phylogenetic trees, using combined 16S and COI data, strongly support the viewpoint that all the P. minor individuals form one clade that is in a sister position to Pampus sp. individuals (EU357803, FJ434342-FJ434343, and FJ652423-FJ652427).  相似文献   

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采用低温—盐形成法对蓝圆 Scombermorusniphonius(Cuvier)、马鲛鱼Decapternsmaruadsi(TemmincketSchleget)、海蛇三种海产动物油中高度不饱和脂肪酸进行提取,经皂化、冷冻、过滤、酸化、离心等工序反复处理后,可得碘价为220~250的高度不饱和脂肪酸混和物。探讨了提取过程中的最适工艺条件,并比较了该三种海产动物脂质中的高度不饱和脂肪酸的含量。  相似文献   

18.
《山地科学学报》2020,17(2):373-383
Fire is a natural disturbance occurring every few years in many grasslands ecosystems. However, since European colonization, fire has been highly reduced or even suppressed in Argentinean grasslands, fostering ignitable material accumulation. This has led to occasional catastrophic controldemanding fire events, extended for larger areas. The aims of this work are to study vegetation recovery and change after a non-natural fire event in mountain grasslands. The study area is located in the Ventania mountain system, mid-eastern Argentina. We studied vegetation recovery after fire(January 2014) in two different communities: grass-steppes(grasslands) and shrub-steppes(open low shrublands). We measured vegetation cover, species richness and bare ground percentage in burned and unburned areas 1, 4, 8, 11 and 23 months after fire. Vegetation surveys were also performed at the end of the growing season(December) 11 and 23 months after fire. Data were analyzed using regression analysis, ANOVA and multivariate analysis(NMS, PERMANOVA). Both communities increased their vegetation cover at the same rate, without differences between burned and unburned areas after two years. Species richness was higher in shrublands and their recovery was alsofaster than in grasslands. Considering functional composition, besides transient changes during the first year after fire, there were no differences in abundance of different functional vegetation groups two years after fire. At the same time, shrublands showed no differences in species composition, while grasslands had a different species composition in burned and unburned plots. Also, burned grassland showed a higher species richness than unburned grassland. Data shown mountain vegetation in Pampas grassland is adapted to fire, recovering cover and richness rapidly after fire and thus reducing soil erosion risks. Vegetation in mountain Pampas seems to be well adapted to fire, but in grasslands species composition has changed due to fire. Nonetheless, these changes seem to be not permanent since prefire species are still present in the area.  相似文献   

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6个不同鲤群体的形态差异分析   总被引:4,自引:0,他引:4  
对黄河鲤、荷包红鲤、高背荷包红鲤、兴国红鲤、建鲤和黑龙江野鲤等6个鲤群体的12个形态比例性状进行单因素方差分析、主成分分析和聚类分析。单因素方差分析结果表明,除眼后头长/头长外,各鲤群体间在其他比例性状上出现较明显的差异。主成分分析构建了3个主成分,其贡献率分别为35.316%、23.221%、10.146%,累计贡献率为68.683%,并明显可将6个鲤群体划分为2个簇,荷包红鲤和高背荷包红鲤明显与其他群体区分开。聚类分析结果与主成分分析一致。在体高/体长、头长/体长、体厚/体长和尾柄高/尾柄长等4个比例性状上,有些群体的差异系数大于1.28,说明这些群体在这4个指标上的差异可达到亚种水平。结果表明,6个鲤群体在形态上存在一定差异和分化,主要体现在体型和头部特征上。  相似文献   

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Abstract Zinc (Zn) and copper (Cu) concentrations were determined in the tissues (muscle, stomach, liver, gills, skin, and gonads) of five commercial fish species (mullet Liza haematocheilus, flathead Platycephalus indicus, mackerel Scomberomorus niphonius, silver pomfret Pampus argenteus, and sea bass Lateolabrax japonicus) from Laizhou Bay in the Bohai Sea. Metal bioaccumulation was highest in the metabolically active tissues of the gonads and liver. Bioconcentration factors for Zn were higher in all tissues (gonads 44.35, stomach 7.73, gills 7.72, liver 5.61, skin 4.88, and muscle 1.63) than the corresponding values for Cu (gonads 3.50, stomach 3.00, gills 1.60, liver 5.43, skin 1.50, and muscle 0.93). Mackerel tissues accumulated metal to higher concentrations than did other fish species, but bioaccumulation levels were not significantly correlated with the trophic levels of the fish. Zn and Cu concentrations in the tissues were generally negatively correlated with fish length, except for a few tissues of sea bass. Risk assessment based on national and international permissible limits and provisional tolerances for weekly intake of Zn and Cu revealed that the concentrations of these two metals in muscle were relatively low and would not pose hazards to human health.  相似文献   

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