基于SVM的多方位声散射数据协作融合鱼分类与识别

为解决基于声散射数据的鱼分类与识别问题,提出了一种基于SVM的多方位声散射数据协作融合鱼分类方法。首先,提取多方位声散射数据的小波包系数奇异值、时域质心及离散余弦变换系数特征,并进行特征融合;然后,采用支持向量机(SVM)分类器对每个方位提取的特征做出决策,并将决策结果表示成后验概率的形式,同时利用每个方位的决策概率对其他方位的决策进行加权;最后输出分类结果。采用3类鱼作为研究对象,得到不同方位数量条件下基于协作融合方法的分类正确率最终达到92%以上。试验数据处理结果表明,随着方位数量的增加,总体分类正确率呈升高的趋势,基于SVM的协作融合方法可以有效提高分类正确率。

常用鱼药的分类及在使用中存在的问题

对我国常用鱼药进行了分类 ,指出了目前国内鱼药使用过程中存在的主要问题 ,并对鱼药规范化管理作了一些设想。

分子技术在太平洋地区古代鱼骨分类上的最新应用

到目前为止,对于太平洋考古遗址出土的古代鱼类骨头的种属判别,通常还是依赖于相对有限数量的骨架构件的形态来分析。但是相较于其他物种而言,鱼类之间形态上的差异很有限,这就经常使对太平洋地区古代鱼骨的分类,只能精确到“科”的水平,有时偶尔能达到“属”。这种相对来说不太精确的分类,很有可能会把史前人类的捕鱼状况及其生存方式的某些重要信息给掩盖掉。新西兰奥克兰大学人类学系太平洋古生态研究实验室的A.Nicholls等人运用一种新的分子技术。

A Systematic Revision of "Barbodes" Fishes in China

The genus Barbodes Bleeker is a catchall group.The species assigned to this genus in China actually belong to at least four distinct genera.After comparing all the Barbodes fishes included in this research to the system used by Rainboth,reassign Barbodes fishes in China as following:①B.baoshanensis,B.benasi and B.heterostomus are assigned to genus Neolissochilus;②B.parvus are assigned as Discherodontus parvus;③B.pierrei in Yunnan is conspecific with B.vernayi and B.vernayi should be assigned to the genus Hypsibarbus as Hypsibarbus vernayi;④the remaining Barbodes fishes,B.fuxianhuensis,B.chonglingchungi,B.margarianus,B.huangchuchieni,B.cogginii (=B.daliensis),B.rhomboides,B.carinatus,B.opisthopterus and B.exiguus are assigned to genus Poropuntius.

Pollution of Environmental Endocrine Disrupting Chemicals(EDCs) in Water and Its Adverse Reproductive Effect on Fish

Environmental endocrine disrupting chemicals （EDCs）, commonly found in the environment, come from industry and agriculture, including pesticides, fungicides, insecticides, herbicides, and other chemicals. Nowadays, more and more EDCs were released into the environment. EDCs go into water body via atmosphere sedi-mentation, surface runoff, soil eluviation, etc., so water body becomes the main place for existing. In order to attract scientific and public attention worldwide and to prevent EDCs pol ution, in this study we reviewed the classification of EDCs and their concentrations in natural water bodies, drinking water sources and water plants, and the reproductive toxicity of EDCs to fish were reviewed. EDCs could disturb the endocrine system and make reproductive organs and reproduction abnor-mal, resulting in fertility descending, reproduction function damage, community quan-tity decrease and even species extinction. In addition, EDCs could disrupt the homeostasis maintained by hormones, which would result in defects of neural de-velopment and abnormalities of the endocrine and reproductive systems. The exact molecular mechanisms have not been completely reported, but researches have suggested that multiple mechanisms were involved in the action of EDCs. Although there have been researches on the biohazard of EDCs, there stil exist problems of weakness in fundamental researches, difficulties in recognizing and identifying EDCs and high cost, which restraint the knowledge on them.

Distribution and Length-weight Relationships of Glyptosternoid Fishes in the Drung River Basin, Yunnan

Glyptosternoid fishes are a group of sisorid catfishes living in torrents of rivers mainly originating from the Qinghai-Tibet Plateau. Based on our survey in the Drung River Basin, seven collecting sites were investigated and 271 glyptosternoid fishes caught belong to three species （Pareuchiloglanis kamengensis, Exostoma labiatum and Oreoglanis mocropterus）. Features of the distribution of the three catfishes were assessed. More individuals of E. labiatum were caught in the lower reaches of the Drung River with fast water velocity and it might be more adapted to a torrent habitat. The relationships between standard length （L） and weight （W） for P. kamengensis, E. labiatum and O. macropterus were also studied, and the parameter b of the L-W relationship （W = aL^b） ranged between 2. 8201 and 3. 0131. From the present study, all the three catfish species grow allometrically and the growth type of E. labiatum is the closest to a symmetrical one.

PHYLOGENETIC RELATIONSHIPS OF THE ENDEMIC CHINESE CYPRINID FISH Pseudogyrinocheilus prochilus

Evidence is provided to support the hypothesis that the taxa Pseudogyrinocheilus, Semilabeo, and Discolabeo form a monophyly in which Semilabeo and Discolabeo are sister groups, and both together constitute the sister group of Pseudogyrinocheilus. On the basis of phylogenetic relationships of Pseudogyrinocheilus to others, it is proposed that the taxon Pseudogyrinocheilus be a valid genus. In addition, comments are made on importance of some features used in the traditional taxonomy of the subfamily Labeoninae.

Possible genetic reproductive isolation between two tilapiine genera and species:Oreochromis niloticus and Sarotherodon melanotheron

Successful crossbreeding between Oreochromis niloticus and Sarotherodon melanotheron to produce a commercial hybrid has been difficult.The karyotypes and isoenzyme of these two species and their reciprocal hybrids（O.niloticus ♀ × S.melanotheron ♂,S.melanotheron ♀ × O.niloticus ♂,the last not included in the isoenzyme study） were investigated via metaphase chromosomes obtained from head kidney cells and electropherogram of lactate dehydrogenase（LDH） isoenzymes from the liver,kidney,white muscle,heart,and eye balls.The diploid chromosome number（2n=44） and the fundamental number（NF=50） of the four tilapia genotypes were the same.However,the karyotype of O.niloticus had three pairs of sub-metacentric（sm）,twelve pairs of sub-telocentric（st）,and seven pairs of telocentric（t） chromosomes,while S.melanotheron had one pair of metacentric（m）,two pairs of sm,12 pairs of st,and seven pairs of t chromosomes.The reciprocal hybrids both showed a mixed karyotype range between their parents：0.5 pair of m,2.5 pairs of sm,12 pairs of st,and seven pairs of t chromosomes.In view of the electropherogram of isozymes,only the LDH of the kidney showed significant clear bands,with five bands in O.niloticus,three bands in S.melanotheron,and duplicated six bands in the hybrids.The bands varied depending on their activities and mobilities.We considered that the differences in karyotype and isoenzyme were related to the genetic mechanism for post-mating isolation,and provided some additional basic genetic background of their taxonomy.

Taxonomical notes on selected freshwater fish species described from northern and central Vietnam （Cypriniformes： Balitoridae, Cobitidae, Cyprinidae, Nemacheilidae; Perciformes： Channidae, Osphronemidae; Synbranchiformes： Mastacembelidae）

Selected,little known taxa of northern and central Vietnamese freshwater fish species are reviewed.Nomenclatural acts are taken:Hemibarbus lehoai is placed in synonymy of H.maculatus,Paracobitis hagiangensis in synonymy of Schistura caudofurca.A neotype of Micronemacheilus bacmeensis is assigned.The name Channa hanamensis is treated as a nomen nudum.Two labeonine species described from China are nomenclaturally affected:Garra findolabium is transferred to Vinagarra and its specific epithet is treated as a noun in apposition;the specific epithet of Sinigarra napoense is corrected to napoensis.

Random amplified polymorphic DNA analysis of eel genome

Eel family is a huge one, in which many kinds of eelsespecially some migratory eels, bear strong resemblance toeach other, and are therefOre difficult to be identified. Inthis study 29 random primers were used to make RAPDana1ysis for Japanese ee1 (Angui11ajaponica). European eel(Anguilla anguilla) and Pike eel (AIllrae1lesox cinereus).And totally 299 fragments were counted. Shared or spe-cific fragments were counted alld ge11etic similarity or ge-netic distance were calculated. The genetic similarity be-tween Japanese eel alld Pike eel is 0.68 and the geneticdistance between them is 0.32; those between Europeaneel and Pike eel are 0.72 and 0.28 respectively, and be-tween Japanese eel and Ellropean eel are 0.74 and 0.25 re-spectively. The method has been shown to be suitable tomolecular identification of eels. It provides an a1ternativeapproach to determine the relatiollship between species.

Variation in the distribution of wintering anchovy Engraulis japonicus and its relationship with water temperature in the central and southern Yellow Sea

In the present study,we investigated a shift in the spatial distribution of wintering anchovy(Engraulis japonicus)and its relationship with water temperature,using data collected by bottom trawl surveys and remote sensing in the central and southern Yellow Sea,during 2000–2015.Our results indicate that the latitudinal distribution of wintering anchovy varied between years,but there was no consistent pattern in the direction of change(north or south).Wintering anchovy did not move northward with increasing water temperature.However,the latitudinal distribution of wintering anchovy correlated well with 10°C and 11°C isotherms.The results of both a one-step and a two-step generalized additive model indicated that water temperature was associated with both presence and biomass of wintering anchovy.This paper is the fi rst to systematically examine the relationship between anchovy distribution and water temperature using a variety of techniques.All the fi ndings confi rm the impact of water temperature on wintering anchovy distribution,which has important implications for the continued management of the anchovy resource and the enhancement of marine fi shery resources in the Yellow Sea,especially as the climate changes.However water temperature only partly explains the species distribution of anchovy,and stock characteristics also aff ect fi shery distribution.Therefore,other factors should be considered in future research.

A Preliminary Study on the Diversity of Fish Species and Marine Fish Faunas of the South China Sea

There are 3048 species of fish occurring in the China Seas （CS）, of which at least 2321 species are found in the South China Sea （SCS）, belonging to 35 orders, 236 families and 822 genera. The fish species diversity is analyzed in this paper based on biogeography, biostatistics, fishing methods, etc. It is found that the regional environment, especially biological factors, plays an important role in the distribution of faunas, and there are two fish faunas in the SCS, one in the north and another in the center and south. This regional division is of value for sustainable fishery production and eiTlcient management of fishery resources.

Status and historical changes in the fish community in Erhai Lake

Erhai Lake is the second largest freshwater lake on the Yunnan Plateau, Southwest China. In recent decades, a number of exotic fish species have been introduced into the lake and the fish community has changed considerably. We evaluated the status of the fish community based on surveys with multimesh gillnet, trap net, and benthic fyke-net between May 2009 and April 2012. In addition, we evaluated the change in the community using historical data （1952-2010） describing the fish community and fishery harvest. The current fish community is dominated by small-sized fishes, including Pseudorasbora parva, Rhinogobius giurinus, Micropercops swinhonis, Hemiculter leucisculus, and Rhinogobius cliffordpopei. These accounted for 87.7% of the 22 546 total specimens collected. Omnivorous and carnivorous species dominated the community. A canonical correspondence analysis （CCA） plot revealed that the distribution of fishes in the lake is influenced by aquatic plants, water temperature, pH, and season. The abundance of indigenous species has declined sharply, and a majority of endemic species have been extirpated from the lake （a decrease from seven to two species）. In contrast, the number of exotic species has increased since the 1960s to a total of 22 at present. The fishery harvest decreased initially following the 1960s, but has since increased due to the introduction of non-native fish and stocking of native fish. The fishery harvest was significantly correlated with total nitrogen, not total phosphorus, during the past 20 years. Based on our results, we discuss recommendations for the restoration and conservation of the fish resources in Erhai Lake.

Spatial distribution and abundance of small fishes in Xiaosihai Lake,a shallow lake along the Changjiang (Yangtze) River, China

Spatial distribution and abundance of small fishes were studied in autumn 2007 in the Xiaosihai Lake, a shallow lake along the middle reach of the Changjiang （Yangtze） River. Based on the plant cover, the lake was divided into three major habitats： Myriophyllum spicaturn habitat （MS habitat）, Trapa bispinosa habitat （TB habitat）, and non-vegetation habitat （NV habitat）. A modified pop-net was used for quantitative sampling of small fishes in the three habitats, and the Zippin＇s removal method was used for estimating densities of the small fishes. A total of 13 species belonging to 5 families were collected, with 11 species in MS habitat, 7 species in TB habitat, and 5 species in NV habitat. Habitat type had significant effect on the spatial distribution of small fishes. The Shannon-Wiener diversity index in the MS, TB and NV habitats were 1.28, 0.56 and 0.54, respectively. The total density and biomass of small fishes were significantly higher in the MS habitat （13.68 ind/m^2 and 4.44 g/m^2） than in the TB habitat （1.41 ind/m^2 and 0.54 g/m^2） and the NV habitat （1.08 ind/m^2 and 0.40 g/m^2）, and were not significantly different between the TB habitat and the NV habitat. Water depth had no significant effect on spatial distribution of the small fishes. It was suggested that vegetation type played an important role in habitat selectivity of small fishes, and the presence of submersed vegetation should be of significance in the conservation of small fish diversity.

Acute toxicity of live and decomposing green alga Ulva (Enteromorpha) prolifera to abalone Haliotis discus hannai

From 2007 to 2009, large-scale blooms of green algae (the so-called "green tides") occurred every summer in the Yellow Sea, China. In June 2008, huge amounts of floating green algae accumulated along the coast of Qingdao and led to mass mortality of cultured abalone and sea cucumber. However, the mechanism for the mass mortality of cultured animals remains undetermined. This study examined the toxic effects of Ulva (Enteromorpha) prolifera, the causative species of green tides in the Yellow Sea during the last three years. The acute toxicity of fresh culture medium and decomposing algal effluent of U. prolifera to the cultured abalone Haliotis discus hannai were tested. It was found that both fresh culture medium and decomposing algal effluent had toxic effects to abalone, and decomposing algal effluent was more toxic than fresh culture medium. The acute toxicity of decomposing algal effluent could be attributed to the ammonia and sulfide presented in the effluent, as well as the hypoxia caused by the decomposition process.

A Microsatellite Genetic Linkage Map of Black Rockfish(Sebastes schlegeli)

Ovoviviparous black rockfish(Sebastes schlegeli) is an important marine fish species for aquaculture and fisheries in China. Genetic information of this species is scarce because of the lack of microsatellite markers. In this study, a large number of microsatellite markers of black rockfish were isolated by constructing microsatellite-enriched libraries. Female- and male-specific genetic linkage maps were constructed using 435 microsatellite markers genotyped in a full-sib family of the fish species. The female linkage map contained 140 microsatellite markers, in which 23 linkage groups had a total genetic length of 1334.1 c M and average inter-marker space of 13.3 c M. The male linkage map contained 156 microsatellite markers, in which 25 linkage groups had a total genetic length of 1359.6 c M and average inter-marker distance of 12.4 c M. The genome coverage of the female and male linkage maps was 68.6% and 69.3%, respectively. The female-to-male ratio of the recombination rate was approximately 1.07:1 in adjacent microsatellite markers. This paper presents the first genetic linkage map of microsatellites in black rockfish. The collection of polymorphic markers and sex-specific linkage maps of black rockfish could be useful for further investigations on parental assignment, population genetics, quantitative trait loci mapping, and marker-assisted selection in related breeding programs.

Molecular phylogeny and evolution of Scomber(Teleostei:Scombridae)based on mitochondrial and nuclear DNA sequences

A molecular phylogenetic analysis of the genus Scomber was conducted based on mitochondrial(COI,Cyt b and control region) and nuclear(5S rDNA) DNA sequence data in multigene perspective.A variety of phylogenetic analytic methods were used to clarify the current taxonomic classification and to assess phylogenetic relationships and the evolutionary history of this genus.The present study produced a well-resolved phylogeny that strongly supported the monophyly of Scomber.We confirmed that S.japonicus and S.colias were genetically distinct.Although morphologically and ecologically similar to S.colias,the molecular data showed that S.japonicus has a greater molecular affinity with S.australasicus,which conflicts with the traditional taxonomy.This phylogenetic pattern was corroborated by the mtDNA data,but incompletely by the nuclear DNA data.Phylogenetic concordance between the mitochondrial and nuclear DNA regions for the basal nodes supports an Atlantic origin for Scomber.The present-day geographic ranges of the species were compared with the resultant molecular phylogeny derived from partition Bayesian analyses of the combined data sets to evaluate possible dispersal routes of the genus.The present-day geographic distribution of Scomber species might be best ascribed to multiple dispersal events.In addition,our results suggest that phylogenies derived from multiple genes and long sequences exhibited improved phylogenetic resolution,from which we conclude that the phylogenetic reconstruction is a reliable representation of the evolutionary history of Scomber.

Distribution and Diversity of Candida tropicalis Strains in Different Marine Environments

1089 strains of yeasts were obtained from seawater,sea sediments,mud of sea salterns,guts of marine fishes,mangroveplants and marine algae.The results of routine identification and molecular analysis methods show that 44 strains among the marineyeasts obtained in this study belong to Candida tropicalis,which may indicate its wide distribution in different environment,especially in the tropical and subtropical marine environment.The wide distribution of C.tropicalis indicates that it may play an important role in marine environment and the marine environment in turn is a good source for obtaining C.tropicalis.

Do physicochemical variables regulate the distribution of zooplankton communities in reservoirs dominated by filter-feeding carp?

The temporal and spatial distributions of zooplankton communities in the upper, middle, and lower reaches of the Xin＇anjiang Reservoir, Zhejiang, China, were investigated monthly, between 2009 and 2010. Silver carp （Hypophthalmichthys moBtrix） and bighead carp （Aristichthys nobilis） dominated the pelagic fish community of this large, deep reservoir. Cladocerans were distributed evenly throughout the reservoir. Rotifers were mainly found in the upper reaches, while copepods tended to assemble in the lower reaches. The Pearson correlation analysis and stepwise multiple regression were used to identify the major physicochemical gradients influencing community variations. Zooplankton community distributions were influenced by water temperature, dissolved oxygen, phosphorus, nitrogen, and silicon. Excess nutrients, in particular silicon, stimulated rotifer growth. Based on these findings, it is possible to use rotifer density as a bioindicator of eutrophic status in deep reservoir ecosystems.