Abstract:The Pampus fishes are important commercial species and widely distributed in the coastal waters of China.Due to the similarities and complexities of morphological characters used in traditional taxonomy,taxonomic confusion has arisen in Pampusconcerning the nomenclature.Among the genus,perhaps none is more confusing in the taxonomic studies than Pampus argenteus.Up to date,no reports about neotype of P.argenteus can be found.In the present study,redescription of morphological characters and redefinition of DNA barcoding of P.argenteus are conducted based on sixteen specimens collected from Kuwait(northern waters of Kuwait),Pakistan(Sonmiani Bay,Ormara,Pasni),Beibu Bay and Taiwan during October 2010 to September 2012.The diagnostic characters of P.argenteus:dorsal fin Ⅶ-Ⅷ-39-43,pectoral fin 21-29,anal fin Ⅴ-Ⅵ-35-41,caudal fin 26-28.First gill arch with 10-12［(2-3) (8-9)］small and sparse gill rakers.Vertebrae 37-38.In the occipital region,the area of the wavy branches above lateral line is developed and plume-like,with a little obtuse edge.Ventral wavy branches below lateral line are curvy and shorter than that above lateral line,and not reaching the base of dorsal fin.Combining all COⅠ sequences of P.argenteus from GenBank with those of this study,four absolute groups can be found in all specimens based on the genetic differences in amino acids and distance between groups.From the NJ tree,we can find that only one sequence(FJ384702)is similar to our DNA barcoding of P.argenteus.Therefore,it is urgent to guarantee the correctness of all sequences from GenBank.Redescription of morphological characters and the right DNA barcoding of P.argenteus are given,which provide a guarantee for efficient and accurate study,and theoretic basis for classification of Pampus in future.

Abstract:To investigate the effects of different starvation periods on the growth capacity,feeding and activities of digestive enzyme of the Myxocyprinus asiaticus larvae under the condition of water temperature(19±0.5)℃,two experiments were performed.The first one was a controlled experiment with one complete starvation group(S)and one normal feeding group(C).The second was the delayed first feeding experiment along with the initial feeding time groups:0(control group),1,3,5,7,9 and 11 delayed days groups,denoted as D0,D1,D3,D5,D7,D9 and D11.The total experimental period lasted 29 days.Results showed that:(1)Since hatching,larvae’s first feeding was on the 7th day,and the yolk was exhausted on the 14th day,while PNR(the point of no return)appeared on the 27th day,with conspicuous pectoral angle characteristics and significant increase in mortality around the PNR.(2)After refeeding,compared to the control group,the D1 and D3 groups showed no significant difference in body weight,indicating a complete compensation effect.(3)During the 1th to the 7th day starving process,the trypsin and amylase enzyme activity decreased significantly(P<0.05),while when prolonging the starvation time to 9 and 11 days,the lipase and trypsin enzyme activity rose significantly(P<0.05).After refeeding,with starvation time lasting,to the 19th day larvae,the trypsin activity significantly increased and then gradually decreased,but indicated the opposite trend on the amylase activity,to the 29th day larvae,and both of lipase and amylase showed a significant upward trend.To sum up,our results indicated that starvation can cause significant changes of M.asiaticus in the larvae growth,feeding and digestive enzymes,along with different compensatory growth mechanism after various starvation time periods.After recovering feeding,the digestive enzymes recovery strategy is not consistent for larvae are with different starvation time.Totally,larvae are inclined to use the small carbohydrates along with starvation time lasting.But the inherent mechanism needs further study.

Abstract:To analyze the genetic diversity of natural population and select the specific microsatellite markers for identifying effectively genetic characteristics of population in Japanese flounder( Paralichthys olivaceus) in this study,seventy-four wild individuals captured from the Bohai Sea were used to form the experimental population.A set of 72 microsatellite markers located on different regions in linkage group were chosen to carry out the genetic analysis.In these markers,17 were located in the centromeric region,36 in the distant region from the centromere and 19 in the intermediate region of linkage groups.Analysis showed that the number of alleles(A)ranged from 6.400 to 7.389,number of effective alleles(N_e)ranged from 4.469 to 5.129 and Shannon’s information index(I)ranged from 1.565 to 1.683 in different regions of linkage group.The observed heterozygosity(H_o),unbiased expected heterozygosity(H_e)and polymorphism information content(PIC)was from 0.568 to 0.593,from 0.738 to 0.753 and from 0.707 to 0.746,respectively.The Hardy-Weinberg departure value(d)was lower than -0.200,while,genetic distance(GD)among individuals in population was above than 0.620.Each genetic parameter demonstrated that there was richer genetic diversity in experimental population and relatively farther genetic distance among individuals.This population was suitable for conducting selective breeding as founder population.Significant difference did not exist in the genetic parameters obtained by microsatellite markers located on different regions in linkage group,which verified that there was no necessary correlation between the positions of marker located and the degree of genetic diversity of markers.However,these polymorphic markers could be used as marker candidates to analyze the genetic structure in population of Japanese flounder.

Abstract:A 10-week feeding trial was conducted to investigate effects of lysine on growth,physiological and biochemical indexes of blood and essential amino acids of plasma in juvenile Megalobrama amblycephala.Six isonitrogenous and isoenergetic semi-purified diets were formulated to contain graded dietary lysine levels,and the values were 1.29%,1.71%,2.09%,2.48%,2.88% and 3.27%,respectively.At the initiation of experiment,fish［(3.34±0.03)g］were randomly chosen and sorted into eighteen cages with 30 fish per cage.Each experimental diet was randomly assigned to triplicate cages in a completely randomized design.At the end of feeding trial,final body weight(FBW),weight gain rate(WRG),specific growth rate(SGR),Nitrogen retention efficiency(NRE),protein productive value(PPV)and protein efficiency ratio(PER)of fish fed diet containing 2.48% lysine were significantly higher than those fish fed 1.29% lysine diet while feed conversion ratio(FCR)showed an adverse tendency,but no significant difference was observed in survival rate(SR)of fish fed different dietary methionine levels.Increased crude protein and reduced viscerosomatic ratio(VR)were observed in fish fed 2.48% lysine diet.Ash of whole body of fish fed 2.88% and 3.27% lysine diet was higher than those fish fed 1.29% lysine diet.Alanine aminotransferase(ALT)and total protein(TP)contents were significantly improved with increasing lysine levels up to 3.27%.Urea content in plasma of fish fed 2.94% lysine diet was lower than those fish fed 1.29% lysine diet.Fish fed the 2.88% lysine diet demonstrated a significant improvement in plasma lysine content and total essential amino acid except for Leu and Val.On the basis of SGR and PPV,the optimum dietary lysine requirement of juvenile M.amblycephala was estimated to be 2.36% of diet(6.94% of protein)and 2.22% of diet(6.53% of protein),respectively,using broken-line regression analysis.

Abstract:The worldwide climate and marine environmental changes have significant impacts on the distributions and fishery resources abundance fluctuations of Dosidicus gigas in the East Pacific Ocean.It is important to investigate genetic variance and population genetic structure of D.gigas in order to exploit and manage this squid scientifically.In this study,the genetic diversity and the genetic differentiation between two geographical populations of D.gigas were analyzed based on two mitochondrial DNA molecular markers.The results showed that the number of haplotype,haplotype diversities,nucleotide diversities and average nucleotide differences were 7,(0.397±0.079),(0.001 09±0.000 96) and 0.600 respectively in all Cytb sequences of two geographical populations,and haplotype diversity in population off the coast of Peru was only(0.282±0.101)which was significantly lower than that of equatorial waters.On the other hand,the number of haplotype,haplotype diversities,nucleotide diversities and average nucleotide differences in all COⅠ sequences were 17,(0.787±0.051),(0.002 90±0.001 38)and 1.802 respectively.The pairwise fixation index F_st and median network revealed lack of genetic structure between populations of equatorial waters and off the coast of Peru(Cytb:F_st=0.055 23,P>0.05;COⅠ:F_st=0.005 91,P>0.05),and this might be caused by equational oceanographic current.The minimum spanning network tree,mismatch distribution analysis and neutrality tests suggested that D.gigas experienced a recent population expansion,possibly 138 900 to 167 900 years ago.

Abstract:The present study was conducted to estimate the optimum requirement of dietary available phosphorus for adult GIFT strain of Nile tilapia Oreochromis niloticus reared in freshwater.Six semi-purified diets were formulated to contain graded levels(0.15%,control diet,0.40%,0.66%,0.91%,1.17% and 1.43%t)of available phosphorus(KH₂PO₄ was the source of phosphorus).Each diet was fed to triplicate groups of 20 fish with initial average weight(184.46±8.13)g for 9 weeks.The results showed that fish fed the two diets with available phosphorus levels of 0.66% and 0.91% had significantly higher weight gain rate(WGR)and specific growth rate(SGR)than those fed the other diets(P<0.05),and the feed efficiency(FE)was significantly higher than that of control diet(P<0.05).The whole body viscerosomatic index(VSI),hepatosomatic index(HIS)and condition factor(CF)decreased significantly with the increases of the dietary available phosphorus levels(P<0.05),while the survival rate(SR)of fish had no significant differences among various dietary treatments(P＞0.05).Crude protein,ash,and phosphorus concentration in whole body increased significantly with the increases of the dietary available phosphorus levels,as well as vertebrae and scale ash and phosphorus concentration(P<0.05).Crude lipid concentration in whole body decreased significantly with the increases of the dietary available phosphorus levels(P>0.05).Quadratic curve analysis based on SGR indicated that the minimum dietary requirement of available phosphorus for maintaining maximal growth of tilapia was 0.85%.

Abstract:Serine proteinase inhibitors (SPI) play an important role in regulating humoral immune by controlling the activity of serine proteinase (SP) in the process of protease cascade. Serpin family members participate in numerous biological processes by regulating the activity of serine and cysteine proteinases, such as blood clotting, complement activation, fibrinolysis function, inflammation, tumor suppressor and hormone transfer process. In our previous research, we cloned a serpin-type serine proteinase inhibitiorSPI gene was cloned from hemocytes of Chinese shrimp (Fc-serpin, GenBank accession number: DQ318857). The transcript of Fc-serpin was induced in response to the infection of bacteria and white spot syndrome virus (WSSV). In this research, recombinant Fc-serpin (rFc-serpin) was successfully expressed in bacteria E.coli and purified for further research of bioactivity. The concentrations of purified target proteins were 0.3g/L. rFc-serpin showed in vitro antimicrobial activity against main pathogens including Gram-positive, Gram-negative bacteria and fungi.These results suggests that rFc-serpin might play a crucial role in the innate immunity of the shrimp and is expecting to be applied in disease control.

Abstract:Exopalaemon modestus is one of the main shrimps which has high economic value.But its genetic information and functional gene background are rarely known so far.In this study,the cDNAs of four novel C-type lectins(designated as EmCTL-1,EmCTL-2, EmCTL-3 and EmCTL-4)were cloned from the ovary of white shrimp,E.modestus,by means of PCR and 5′and 3′rapid amplification of cDNA ends (RACE).The full-length cDNAs consist of 1 390,1 119,1 364 and 1 299 bp with one open reading frame consisting of 996,969,1 026 and 1 044 bp,encoding 332,322,341 and 347 amino acids respectively.Their deduced amino acid sequences contained a putative signal peptide of 19,21,20 and 17 amino acid residues respectively.The four C-type lectin genes all contained two carbohydrate recognition domains,CRD1 and CRD2.The CRD1 was composed of 128 residues in EmCTL-2 and EmCTL-3,127 residues in EmCTL-1 and 126 residues in EmCTL-4. And the CRD2 was composed of 127 residues in EmCTL-1 and EmCTL-3,129 residues in EmCTL-2 and 130 residues in EmCTL-4.Both the CRD1 and CRD2 had 6 conserved cysteine residues and 3 conserved tryptophane residues.The motif of Ca² binding sites 2 were EPA and FND in EmCTL-1,EPA and FHD in EmCTL-2,WHD and FDD in EmCTL-3 and EPD and FRD in EmCTL-4.So EmCTL-1,EmCTL-2 and EmCTL-4 can be deduced binding with mannose in immune reactions.And the four C-type lectin genes shared 40%,37%,69% and 73% identity with the parallel C-type lectin genes in Macrobrachium rosenbergii,existing in Palaemonidae.The CODEML program implemented in the PAML package was used to test for variations in selective pressures of shrimp and prawns C-type lectin genes with two CRDs,included the four genes acquired in this study.The result showed that the shrime and prawns lectin genes with two CRDs had undergone positive selection.According to the LTR test,3.8% of the sites were driven by positive selection in the M2a model,while 5.6% of the sites were driven by positive selection in the M8 model.Phylogenetic analysis showed that the lectins from the decapods could be divided into four clear clusters.Cluster C included the dual-CRD lectins while cluster D includ the single-CRD lectins,and cluster A included the dual-CRD lectins except the PmCTL-1 in tiger shrimp,cluster B included the single-CRD lectins except the FcCTL in Chinese shrimp.It indicated that the numbers of CRD played a key role in phyletic evolution.The results showed that EmCTL-1,EmCTL-2, EmCTL-3 belonged to cluster C and EmCTL-4 belonged to cluster A.Four novel C-type lectin genes in E.modestus had a close evolutionary relationship to the C-type lectins of giant freshwater prawn.Tissue distribution analysis using semi-quantitative RT-PCR methods showed that EmCTL-1 was main expressed in hemolymph,testis and ovary.EmCTL-3 and EmCTL-4 could be detected main in testis,ovary,hepatopancreas,hemolymph,heart and thoracic ganglion while EmCTL-2 was mainly expressed in ovary,testis,hemolymph,thoracic ganglion and heart.The results showed that the hemolymph was the mainly expression tissue of four C-type lectin genes in E.modestus.Interestingly,and the testis was the organ with highest expression level of C-type lectin transcripts in this study.It can be speculated that the C-type lectins in E.modestus may agglutinate microorganisms in the hemolymph for possessing signal peptides,conserved cysteine residues,conserved tryptophane residues,high expression level in hemolymph and observed positive selection.

Abstract:In order to understand the influence and mechanism of temperature on the virulence of Streptococcus agalactiae,the effects of culture temperature on the virulence related parameters of S.agalactiae including bacteria growth,adhesion,invasion,expression of virulence genes and mortality rates of tilapia were studied.The results showed that the growth speeds of S.agalactiae at different temperatures(25-40 ℃)were different;37 ℃ was the optimum growth temperature and the slowest growth speed appeared at 25 ℃.The adhesive capacity of S.agalactiae reached the peak at 37 ℃ and decreased at 40 ℃.There was no significant difference between the absorbance(OD_{590 nm})of adhesive S.agalactiae incubated in the range of 25-34 ℃.The number of colony forming units in the brain of tilapia infected artificially with S.agalactiae showed a temperature-dependent growth pattern.The number of colony forming units increased along with the increase of culture temperature and reached the peak at 37 ℃,and then decreased at 40 ℃.The number of colony forming units was positively associated with its mortality rate.The expression of virulence genes was also influenced by culture temperature.The expression level of hly and cfb genes showed a temperature-dependent expression pattern similar to the number of colony forming units.The expression of hly and cfb genes significantly increased and reached the peak at 34 ℃and 37 ℃,respectively,and then dropped rapidly while the culture temperature continued to rise.The expression of sip gene was minimally influenced by culture temperature while the expression of scpB gene decreased along with the increase of the culture temperature.The mortality rates of tilapia infected with S.agalactiae cultured at different temperatures showed temperature-dependence.The mortality rate increased along with the increase of culture temperature and peaked 66.67%±6.67% at 37 ℃,and then slightly decreased at 40 ℃.In conclusion,the culture temperature influenced the growth,adhesion,invasion and expression of some virulence genes of S.agalactiae,which may contribute to its virulence.

Abstract:For analyzing the hydrodynamic performance of low aspect ratio vertical cambered otter board at different angles of inclination and angle of attack,the lift coefficient(C_L),drag coefficient(C_D),buoyancy coefficient(C_Z)and lift to drag ratio(K)were calculated through the tank model experiment.The experimental results were as follows:(1)C_L and K showed a trend of first increasing and then decreasing with the increase of angle of attack(α),C_D reflected an upward trend with the increase of α;(2)With no angle of inclination,when α=30°,the max lift coefficient(C_Lmax)was 1.699,in this case C_D=1.140,K=1.490.When α=15°,the max lift to drag ratio(K_max)was 2.421,in this case C_L=1.120,C_D=0.463;(3)When the heeling angle(β)changed between -10°-10°,C_Lmax=1.816(α=25°,β=-10°),K_max=3.405(α=10°,β=-10°).The otter board had a certain buoyancy when β was -5° and -10°,the average buoyancy coefficient was 0.16 and 0.25 respectively,when α was between 10°-30°;(4)When the trim angle(γ)changed between -10°-10°,C_Lmax=1.823(α=25° or α=30°,γ=-10°),K_max=2.729(α=5°,γ=-5°).The otter board had a certain buoyancy when γ was -5°,-10° and 5°,the average buoyancy coefficient was 0.16,0.18 and 0.16 respectively,when α was between 10°-30°.It is suggested that the best working scope of angle of attack was between 15°-30°,in which case C_L>1.1 and K>1.45.Finally compared the hydrodynamic performance of different types of otter board,we provided a reference basis for the rational use and further development of the new types of otter board.

Abstract:To study the regulatory role of ecdysteroid receptor(EcR)in molting and ovarian development of crustaceans,the full-length EcR cDNA of Portunus trituberculatus(PtEcR)was cloned by using reverse transcript PCR(RT-PCR)and rapid amplification of cDNA ends(RACE).The full-length of PtEcR(GenBank accession number:KC354381)was 2 231 bp,included a 1 269 bp ORF which encoded 422 amino acid residues.The alignment of amino acid sequence of PtEcR and that of other crustaceans showed that their identities were 67% to 97%.Phylogenetic analysis of EcR showed PtEcR was clustered in crustaceans EcRs and separated from insect EcRs.Quantitative real-time PCR(qRT-PCR)was used to quantify the relative expression level of PtEcR in different tissues,molting process and the second ovarian development in P.trituberculatus .PtEcR was expressed in various tissues and highest in the Y-organ(YO).During the molting process,the expression levels of PtEcR in YO remained low from postmolt period to substages of D2 premolt period,then significantly increased at substages D3 and D4.The changes in the expression levels of PtEcR were consistent with those in the levels of hemolymphatic 20-hydroxyecdysone,which demonstrated that PtEcR played an important role in molting regulation of P.trituberculatus.During the second ovarian development,the expression levels of PtEcR in YO and hepatopancreas gradually increased to the maximum from stage Ⅱ to Ⅳ;The expression levels of PtEcR in ovary at stages Ⅱ and Ⅳ were significantly higher than those at stage Ⅰ and Ⅲ.The results indicated that PtEcR may play an important role during ovarian development in P.trituberculatus.

Abstract:The establishment of aquaculture welfare in circulating water system,based on fishery welfare concept and the characteristics of closed circulating water system of aquaculture,has become a strategic need to promote the sustainable development of modern fishery in China.In this paper,the impact factors of welfare in circulating water system,intensive demands and scientific evaluation standards of aquaculture welfare in circulating water system were analyzed and discussed.The contents of this paper refer to the key technology in circulating water system,cross merging advanced information technology and automatic control technology.The purpose of this paper is to provide theoretical and technical support to set up the criterion of production process control,establish security mechanism in aquaculture welfare,and truly improve quality and safety level of aquacultural product in the future.

Abstract:To analyze the expression pattern of Doublesex(dsx)of Daphnia pulex in different reproductive modes,we extracted total RNA of different reproductive modes’Daphnia pulex.Using RT-PCR and Quantitative real-time PCR analyzed dsx expression in different reproductive modes’ daphnias.In addition,we synthesized DIG labeled RNA probe of dsx by in vitro transcription and used whole mount in situ hybridization researching dsx location expression in different reproductive modes’ daphnia.Results showed that dsx in male and female had no gender specificity of alternative splicing,only a same transcription.Real-time PCR showed dsx highest expression level was in male,which was parthenogenetic female’s 2.6 times and 4.9 times that of the female.They had significant difference(P <0.05)and gender differences in expression each other.Whole mountin situ hybridization found that dsx gene was expressed in the somatic tissure in different from reproductive modes’ daphnia,but the difference in quantity and parts.The expression also showed the gender differences in male and female.In male the signals were revealed in the first antenna,the first thoracic limb and the compound eye.The parthenogenetic female and sexual female corresponding sites’ expressions were relatively weak.These suggested that Doublesex gene likely played a significant role in alternation of generation and sexual differentiation.

Abstract:The specific inhibitors of cytoskeleton and histochemical stain were used to investigate formation of cell polarization during the early development of conchospores in Pyropia haitanensis.Polarized conchospores were observed twice:Anterior-posterior axis is formed in migrating conchospores.After migration,conchospores adhere to the substratum and then apical-basal axis is established.Meanwhile,composition of mucilage around conchospores was studied,and acidic polysaccharides and sulfated polysaccharides were found at the rear end in migrating conchospores and basal portion of up-righted conchospores.These results indicate that mucilage is involved in formation and maintenance of the cell polarization in conchospores.Inhibitors of cytoskeleton prevented the released conchospores from germinating through disturbing the anterior-posterior axis formed in migrating conchospores.It was found that they also affected the establishment of apical-basal axis for abnormal germinations in the inhibitors-treated migrated conchospores.These results indicate that cytoskeleton and mucilage are involved constantly in twice cell polarization formation of conchospores in P.haitanensis.

Abstract:An experiment was conducted for indoor intensive culture of Litopenaeus vannamei for a period of 80-100 d for the purpose of studying the effect of water quality regulating and controlling by water recycling-treating system at low frequency combined with in-pond facilities and the nutrient budgets for indoor intensive shrimp aquaculture.The water recycling-treating system consisted of rough filter,ozonator,air-liquid mixer,foam separator,dark sedimentation pond etc.In-pond facilities contained microvesicle aerators and water purifying nets.Two culture ponds termed as pond 7 and pond 8 were set as experimental and control pond respectively.There were no water exchange and medicine use in both ponds during the culture period.Same in-pond facilities were used in both ponds and 30% of the total volume of water from pond 7 was circularly treated with the water recycling-treating system at 60,88 and 94 d during culture 100 d,respectively,while no water recycling-treating system was used in pond 8.The results showed that the system could significantly remove NO₂-N,COD_Mn and TAN in culture wastewater by 53.4%-64.5%,53.4%-94.4%(P<0.01)and 31.6%-40.4%(P<0.05).TAN and NO₂-N in both shrimp culture ponds remained low and in the safe range for shrimp growth during the culture period while culture in pond 8 was terminated on the 80th day because of the outbreak of shrimp disease.The main water quality parameters in pond 7 and pond 8 during the culture period were as follows:DO 5.07-6.70 mg/L and 4.38-6.94 mg/L,TAN 0.248-0.561 mg/L and 0.301-0.794 mg/L,NO₂-N 0.019-0.311 mg/L and 0.012-0.210 mg/L,COD_Mn 10.88-21.22 mg/L and 11.65-23.34 mg/L.The shrimp growth index in pond 7 was better than that in pond 8.The per unit yields in pond 7 and pond 8 were 1.398 kg/m² and 0.803 kg/m² respectively.The results of nutrient budgets in culture ponds showed that the major source of nutrient input was feed which accounted for 93.70% in pond 7 and 92.37% in pond 8 of total nitrogen inputs.98.77% in pond 7 and 99.09% in pond 8 of total phosphorus inputs were from feed.Original culture water and juvenile shrimp provided 6.30% and 7.63% of the total nitrogen input,while 1.23% and 0.91% of the total phosphorus input in corresponding ponds.The major output of nitrogen and phosphorus(56.45% and 53.26% in pond 7,and 59.86% and 55.79% in pond 8)were culture water including effluent.37.07% nitrogen and 21.37% phosphorus of total outputs in pond 7,and 31.94% nitrogen and 13.11% phosphorus in pond 8 were transformed into harvested shrimp finally,so the feed conversion rate for pond 7 was higher.7.00% nitrogen and 25.37% phosphorus of total outputs in pond 7,and 9.34% nitrogen and 31.10% phosphorus in pond 8 were the results of water leakage and adsorption.The experiment results showed that the water recycling-treating system operating at low frequency combined with in-pond facilities could effectively improve the water quality in pond even with no water exchange and medicine usage during culture period,increased feed conversion rate and ensured a good harvest.

Abstract:The macrozoobenthic assemblages in 7 reservoirs,8 rivers,and 14 lakes of Taihu Lake Watershed were investigated in May,2010.Totally,57 species,belonging to 8 classes,representatives of 4 phyla,were collected.Of those,Insecta(17 species)and Oligochaeta(15 species)were the most abundant in species number.As a whole,the zoobenthic assemblage in this watershed was predominated by Limnodrilus hoffmeisteri.According to cluster analysis(CA),there existed 10 community types in the selected 29 water bodies,15 of which were prevailed by L.hoffmeisteri and 5 of which by Bellamya aeruginosa.The mean density and biomass in the whole basin were 2741.2 ind/m² and 47.2 g/m²,respectively.Oligochaeta was predominant in density(about 91%),and Bivalvia together with Gastropod contributed about 93% of the total biomass.Among the different water body types,there were marginally significant or conspicuous differences in density with the maximum for river and the minimum for reservoir,and in biomass with the maximum for lake and the minimum for reservoir.Meanwhile,the numerical composition of macrozoobenthic groups(i.e.at the taxonomic level of class)differed obviously between the water body types.Although Shannon-Weaver diversity index(H′)was conspicuously correlated with richness(species number,S),H′ was more strongly governed by evenness(J).H′,J,and Margalef species richness(R)in lake and reservoir were all significantly higher than those in river,respectively,and S did marginally conspicuously.The density in lakes with practice of aquaculture was significantly higher than in ones without.The reverse were found for biomass,H′,and J.According to BPI index and H′,the most stations of lake and river were moderately or seriously polluted,and the most reservoirs were clear or slightly polluted based on Wright index.

Abstract:Experimental ecological method was used to compare the oxygen consumption rate and ammonia-N excretion rate between red type and green type Apostichopus japonicus,aiming at the investigation on the optimum environmental range for reproduction and culture conditioning of this species.Sea cucumbers were taken to the laboratory,acclimated for 10 d at five temperatures(7,12,17,22 and 27 ℃),six salinities(23,26,29,32,35 and 38)and five light colors(white,red,yellow,green and blue).The uniform size individuals were separately sampled from the red and green A.Japonicus.The results showed that:1)Oxygen consumption rate(OCR)and ammonia-N excretion rate(AER)were positively correlative to the temperature for both types A.japonicus.Under the test temperatures(7-27 ℃),the increasing OCR values of the red and green types sea cucumbers covered the range of 7.58-25.94 and 13.12-25.61 μg/(g·h)respectively.OCR for the red type was significantly higher than the green one at 7 ℃ and 27 ℃,however,it significantly lower than the green one at 22 ℃(P<0.05).2)The AER for red type was positively correlative to the temperature,while for the green one AER reached the maximum at 17 ℃ and then it declined with the increasing of temperature.The AER for the red and green types were 0.62-2.57 and 0.90-2.22 μg/(g·h),respectively.AER for the red type was significantly higher than that of the green one at 7 ℃,and it significantly lower than the green one at 27 ℃.3)At test salinities of 26 to 38,both of the OCR and AER showed a shape of ‘M’ with the increasing of salinity.OCR for the red and green ones were in range of 15.72 to 21.32 μg/(g·h),14.83 to 21.80 μg/(g·h),and AER was 1.47 to 2.83 μg/(g·h),1.40 to 2.00 μg/(g·h),respectively.OCR of red type was significantly lower than that of the green one in range of salinity 23 to 32(P<0.05),whereas AER only was significantly higher at salinity of 29 between the two types A.japonicus(P<0.05).4)Under different light color treatments OCR values for the red type and the green type covered range of 14.33-21.37 and 15.73-21.59 μg/(g·h),and AER covered 4.00-8.86 and 6.38-8.22 μg/(g·h),respectively.The OCR and AER were significantly different under white light treatment between the two types A.japonicus(P<0.05).This study demonstrated that the red type A.japonicus could tolerate higher temperature and was sensitive to lower temperature,while the green type showed an opposite tendency;The optimum salinity range for two types A.japonicus was 29-32;The green type may have broader light spectrum compared with the red type A.japonicus.Above all,the adaptability of the red and the green type A.japonicus to experimental conditions were well consistent with their natural habitats.

Abstract:The juvenile silver pomfret were cultured in water with salinity 14,25 and 36,respectively,for 96 h.And their serum osmolality,catalase(CAT)and gill V-H - ATPase(VHA),Ca² - ATPase,carbonic anhydrase(CA)activities were tested in different salinity over time in this experiment.In this study,the serum osmolality which fluctuated was positively correlated to salinity,and its variation range is 271-379 mOsm/kg.The serum osmolality of different salinity would return to normal at 96 h.CAT activities of salinity 36 and 14 returned to normal after they rose significantly(P<0.05);the highest point of them was salinity 36 at 8 h.VHA activities rose,then recovered in salinity 14,kept stable in control salinity,fell down then recovered in salinity 36.Ca² - ATPase activities increased significantly when salinity changed(P<0.05),and the variation trend in salinity 14 was more identifiable than that in salinity 36.CA activities in salinity 14 and 36 both increased significantly(P<0.05),and the highest point was found in salinity 36 at 24 h.Through analysis of the data,the serum osmolality was significantly negatively correlated to gill VHA activity(P<0.01),and it was significantly negatively correlated to CA activity(P<0.01)in low salinity adaptation(14 and 25).It also illustrated a contrary trend between serum osmolality and Ca² -ATPase activity in salinity 14.This research proved that serum osmolality which changes with salinity,will activate CAT when silver pomfret adapts to different salinity.And VHA,Ca² - ATPase and CA are playing important roles in osmoregulation.