威海区域海水入侵程度总体稳定

日前,威海市开展了双岛湾沿岸丰水期海水入侵和土壤盐渍化监测。至此,威海市2013年度海水入侵和土壤盐渍化监测工作全部结束。从此次监测结果来看,区域海水人侵程度总体未发生明显变化。     

河北省扇贝养殖区河口区域磷酸盐污染分析

在河北省扇贝养殖区7条主要河流的入海口,分别在丰水期和枯水期对活性磷酸盐进行监测与分析,并采用单因子法进行评价.结果显示:5月枯水期7条入海河口活性磷酸盐含量全部超标,大蒲河入海口磷酸盐含量高达1.177 mg/L,超标39倍;各河口磷酸盐甲均污染指数高达19.44.8月丰水期除戴河口磷酸盐污染指数小于1,属末被污染外,其余各入海河口活性磷酸盐含量也全部超标,丰水期大蒲河入海口磷酸盐含量仍最高,达0.930 mg/L,超标31倍;丰水期各河口磷酸盐平均污染指数也达9.41.河北省扇贝养殖区河口区域磷酸盐含量远远超过国家海洋局制定的<海水增养殖区监测技术规程>中规定的扇贝养殖区第二类水质标准.     

三道河水库水质标识指数评价

2007年8月～2008年4月,对三道河水库的水质进行调查,监测指标包括水温、透明度、浊度、总溶解性固体、电导率、pH值、溶解氧、总碱度、总硬度、总氮、总磷、亚硝酸盐氮、硝酸盐氮、氨氮、可溶性正磷酸盐、化学需氧量、氯化物、硫酸盐等.选取其中的总氮、总磷、溶解氧、化学需氧量、氨氮等5项水质指标,利用综合水质标识指数评价法(WQI)对三道河水库水质进行评价.结果表明三道河水库水质达到国家地表水Ⅱ类标准,枯水期水质要好于丰水期,主要污染因子为氮磷营养盐.     

漳江水体营养盐含量季节变化特征分析

本文以2010—2013年丰、平、枯水期漳江水流断面的水质监测数据为依据,分析漳江氮、磷营养盐含量特征及其季节变化规律。结果显示,漳江NO_3~--N含量范围为1.45~3.50 mg/L,NH_4~+-N含量范围为0.112~0.940 mg/L,NO_2~--N含量范围为0.030~0.188mg/L,PO_4~(3-)-P含量范围为0.005~0.143 mg/L,TN、TP含量范围分别为3.40~5.75、0.104~0.379 mg/L。漳江TN含量全年偏高,呈丰水期=平水期枯水期的变化规律,受点源和面源的双重污染,以面源污染占主导。TP含量在枯水期和丰水期的变化无明显区别,受点源污染与面源污染交互作用。漳江NO_3~--N含量占漳江DIN总量的65.3%以上,是氮的稳定形态,不具有显著季节差异。漳江NH+4-N表现出枯水期高值的特征,主要来源于点源排放污染。PO_4~(3-)-P在枯、平、丰水期均有高值出现。漳江水体各营养盐因子在丰水期和枯水期表现出不同的相关性,在枯水期,NH+4-N、TP和TN三个因子间皆呈极显著正相关,NO_3~--N和PO_4~(3-)-P也表现出极显著正相关;雨季径流对各营养盐因子含量变化的影响则截然不同。     

胶州湾湿地海水中营养盐的时空分布与富营养化

依据2009年2、5、7、8、9、11月海洋环境调查资料,对胶州湾湿地海域营养盐的时空分布和富营养化水平进行了分析研究.结果表明,(1)胶州湾湿地海水中无机氮和活性磷酸盐高含量区基本位于大沽河入海口及其邻近海域,其含量和分布主要由大沽河入海径流所控制；(2)胶州湾湿地海水中无机氮和活性磷酸盐的月际变化明显,其含量基本与大沽河入海径流量呈正相关,即丰水期营养盐含量高,枯水期营养盐含量低；(3)胶州湾湿地海水富营养化水平较高,属磷中等限制潜在性富营养；(4)胶州湾湿地海水的有机污染较为严重,属中度污染；(5)大沽河入海径流是胶州湾湿地海水氮、磷等营养物质的主要来源,海水中氮、磷含量过高导致海水富营养化,应采取有效措施解决这一突出环境问题.     

三道河水库水质标识指数评价

２００７年８月～２００８年４月，对三道河水库的水质进行调查，监测指标包括水温、透明度、浊度、总溶解性固体、电导率、ｐＨ值、溶解氧、总碱度、总硬度、总氮、总磷、亚硝酸盐氮、硝酸盐氮、氨氮、可溶性正磷酸盐、化学需氧量、氯化物、硫酸盐等。选取其中的总氮、总磷、溶解氧、化学需氧量、氨氮等５项水质指标，利用综合水质标识指数评价法（ＷＱＩ）对三道河水库水质进行评价。结果表明三道河水库水质达到国家地表水Ⅱ类标准，枯水期水质要好于丰水期，主要污染因子为氮磷营养盐。     

利用地热养殖南美白对虾技术初探

<正> 近两来,南美白对虾池塘养殖、工厂化养殖、稻田养殖等各种养殖形式及海水、半咸水、人工海水、淡水各种水域均已开展,养殖结果差异很大。我市境内的高阳、雄县、容城一带处于牛陀镇突起,地热资源十分丰富。这些热源,埋深 500～1200m,属氯化物重碳酸钠型水。矿化度、NH_3-N含量较高,pH值多在7.0以上,目前多利用于供暖、洗浴、疗养和大棚种植,在水产上仅局限于罗非鱼的养殖。为更好地开发利用这一资源,调节这一地区的养殖     

渫水河砷污染环境中浮游动物的群落特征研究

受高砷背景的影响,渫水河及其支流存在不同程度的砷污染,为揭示砷污染的生态效应,探寻防治对策,研究了该水域中浮游动物的种群分布和季节变化,分析其密度与砷含量及TN、TP的关系.2006-2007年共进行3次调查,设置8个采样断面;共检出浮游动物166种,其中,原生动物(95种)＞轮虫(55种)＞桡足类(10种)＞枝角类(6种);丰水期有104种,远大于平水期和枯水期.浮游动物现存量以丰水期最高,其次是平水期,枯水期最少;空间分布上以断面Ⅱ最高,黄水河支流高于渫水河干流,而渫水干流中段的现存量最小.种类组成上,由于桡足类和枝角类对重金属污染较为敏感,检出种类极少,且均是耐污型,轮虫则以α-β型种类为主,纤毛虫比例不高,只在断面Ⅱ和断面Ⅳ超过肉足虫比例.渫水河的Shannon-Wiener多样性指数、Simpson物种多样性指数、Margalef物种丰富度指数和Pielou均匀度指数值均＜2.生物多样性指数与As含量不相关(r=0.674),但轮虫密度与As含量显著相关(r=0.931).浮游动物密度与TN显著相关(r=0.826),TN对渫水河的浮游动物群落组成起着关键作用,而As只对轮虫的生物量影响较大,并不能决定整个浮游动物的群落结构.     

止锚湾海水增养殖区重金属现状评价分析

2018年采用单因子评价标准对葫芦岛市绥中止锚湾增养殖区海水水质、海洋沉积物和养殖生物体中重金属污染现状做出评价与分析。结果表明:止锚湾贝类养殖区海水重金属各项指标符合国家一类海水水质标准。沉积物重金属各项监测指标符合国家海洋沉积物质量一类标准,养殖贝类铅污染指数介于0.5～1.0,其它监测指标均满足国家海洋生物质量一类标准要求。绥中止锚湾海水增养殖区中重金属含量满足功能区的环境质量要求。     

三峡水库小江流域消落区土壤重金属时空分布与来源分析

2010年3-9月对小江流域消落区5个断面的土壤重金属含量进行监测.结果表明,2010年小江流域消落区土壤Cu、Zn、Pb、Cr、Fe和Mn均值分别为28.90、72.73、23.58、20.70、35.58×103和517.14 mg/kg.土壤综合污染指数为0.99,污染等级处于警戒级.小江消落区土壤重金属含量沿程分布以高阳站点较低,黄石站点较高,且大部分重金属含量随高程升高总体呈现升高的趋势.时间分布上以3月和7月各重金属均值含量较高.与2009年相比,2010年消落区土壤重金属Fe、Mn和Zn含量有所降低,Cu和Pb含量有所增高.利用相关性分析和因子分析对5种重金属的相关性和来源进行解析,结果表明Fe、Mn与其他重金属相关性显著(P＜0.05或P＜0.01),而Cu和Pb也显著相关(P＜0.01),Cr与Fe、Mn之外的重金属的相关性都较弱,初步推断Fe、Mn和Zn属于“自然因子”类别元素,Cu和Pb属于“污染因子”类别元素.     

Surface disinfection of Pacific threadfin, Polydactylus sexfilis, and amberjack, Seriola rivoliana, eggs

The effects of exposing the eggs of Pacific threadfin and amberjack eggs (AEs) to different concentrations of hydrogen peroxide for 5 min on hatch rate and survival were assessed in a series of experiments using a petri dish model rearing system. Despite significant inter‐batch variation in hatch rate, it was shown that eggs of both species could be safely exposed to up to 11 340 mg L⁻¹ H₂O₂ for 5 min. Exposure to 34 230 mg L⁻¹ H₂O₂ for 5 min was shown to be lethal to AEs at a late stage of development. In two further experiments, it was demonstrated that Pacific threadfin eggs were resistant to all tested concentrations of a range of polyvinylpyrrolidone iodine (PVP‐I) concentrations and contact times (up to 1000 mg L⁻¹ PVP‐I for 10 min). The level of bacteria adhering to the eggs of both species was highly variable. Where eggs were heavily colonized (>10⁴ cfu egg⁻¹), hydrogen peroxide concentrations of at least 11 340 mg L⁻¹, or PVP‐I concentrations higher than 500 mg L⁻¹ for 10 min, were required for effective sterilization. In less colonized batches, rinsing in sterile seawater or exposure to lower (550 mg L⁻¹) concentrations of H₂O₂ was sufficient to result in high apparent levels of surface sterility (<1 cfu egg⁻¹).     

Anguilla huangi Teng, Lin, and Tzeng, 2009, is a junior synonym of Anguilla luzonensis Watanabe, Aoyama, and Tsukamoto, 2009

Anguilla luzonensis and A. huangi were each described in 2009 using eels obtained from northern Luzon Island. We examined the taxonomic status of these two groups of eels using morphological and molecular genetic characters. There were no significant differences in two vertebrae counts between eels of A. luzonensis and A. huangi. Mitochondrial 16S ribosomal RNA and cytochrome b genes sequences were obtained and compared among 28 specimens of A. luzonensis, the holotypes of A. luzonensis and A. huangi, and one specimen of the other 15 anguillid species. The specimens of A. luzonensis exhibited almost identical sequences, including the holotype, with only a few site differences, and the genetic difference between the holotypes of A. luzonensis and A. huangi was within the range of differences of specimens of A. luzonensis. The other anguillid species were genetically very different from A. luzonensis and A. huangi, although A. interioris is a closely related species. It is clear that A. luzonensis and A. huangi are the same species, and according to the principle of priority in zoological nomenclature, A. luzonensis Watanabe, Aoyama, and Tsukamoto, 2009 is the valid species name, and A. huangi Teng, Lin, and Tzeng, 2009 is a junior synonym of A. luzonensis.     

Effect of Lead on Survival,Osmoregulation, and Histological Changes of the Gills of the White Shrimp,Litopenaeus vannamei,Boone, 1931

The purpose of this study was to evaluate the acute toxicity of lead for different life stages of shrimp, Litopenaeus vannamei, and to determine the effect of its sublethal concentrations on osmoregulatory capacity (OC) as well as the possible histological alteration in the gills of juvenile shrimp. The 24‐, 48‐, and 96‐h LC₅₀ values for lead to L. vannamei increased progressively with increasing life stage, from nauplii < zoeae < mysis < postlarvae < juvenile. After 15‐d exposure to 3.25, 6.50, and 9.75 mg Pb/L, the OC values of exposed shrimp were reduced by 39, 73, and 157%, respectively compared to control animals. Compared to controls, the lead concentrations in gill tissues increased significantly by 127,500, 137,500, and 141,000% in shrimps exposed to 3.25, 6.50, and 9.75 mg Pb/L, respectively. After lead exposure, hemocytic congestion in efferent vessels and multiple hyperplasia were observed in gill filaments, resulting in narrowed hemolymphatic lacuna. The histopathological effects increased with increasing Pb concentration.     

驼背鲈(Chromileptes altivelis)的胚胎发育及仔、稚、幼鱼形态观察

对驼背鲈(Chromileptes altivelis)的胚胎发育及仔、稚、幼鱼的形态特征进行了详细的观察与研究,描述了从受精卵到仔、稚、幼鱼各发育期的时间和形态特征变化。结果表明,在水温25-26℃、盐度30的海水中,受精卵历时27 h 25 min完成整个胚胎发育过程,经历从卵裂、囊胚、原肠、神经胚到肌节形成、各器官的逐渐形成、变化、完善等一系列的胚胎发育和变化过程;根据其卵黄囊消长情况、鳞片的覆盖状态、体色发生的不同变化以及第二背鳍和腹鳍的消长,将胚后发育分为仔、稚、幼鱼3个阶段。在水温22-26℃、盐度29-31、DO≥5 mg/L的条件下,2-3 d仔鱼卵黄囊消失,开口摄食;生长发育至31 d,仔鱼已变态进入稚鱼期;培育至57 d,稚鱼完成变态,成为幼鱼。第二背鳍棘和腹鳍棘的生长与收缩等石斑鱼类早期发育的共性生长特征及其体表特性体色变化特征为驼背鲈胚后发育过程中最明显的特征。     

Effect of Temperature on Growth,Energy Budget,and Physiological Performance of Green,White, and Purple Color Morphs of Sea Cucumber,Apostichopus japonicus

As an intertidal species, Apostichopus japonicus is subject to diel and seasonal temperature fluctuations. Color variation is a distinct characteristic of A. japonicus, and a new color morph, purple A. japonicus, was recently found on the coast of Rushan, Weihai City. This study was conducted to compare the performance of green, white, and purple color morphs of A. japonicus at different water temperatures to help improving aquaculture technology and management. In this study, green, white, and purple color morphs of juvenile A. japonicus (1.5 ± 0.1 g) were cultured at 10, 14, 18, 22, and 26 C for 60 d, according to the suitable temperature range for sea cucumber growth. Temperature was shown to have a significant effect on growth, energy budget, and physiology of sea cucumbers (P < 0.05). Specific growth rates, feed conversion efficiencies, and the proportion of energy allocated to growth of all three color morphs were optimal at 18 C. Activities of the enzymes related with oxidative stress, immune response, and digestion were determined. Superoxide dismutase (SOD) and trypsin activities generally reached a maximum in all three color morphs at 18 C. The purple color morph of A. japonicus was higher in growth rate, food conversion efficiency, and proportion of energy allocated to growth than green and white color morphs at 18 and 22 C, consistent with its higher trypsin and SOD activity, indicating the mutual effect of growth and physiology. At 18, 22, and 26 C, the green color morph had the highest level of lysozyme activity and purple color morph had the lowest, indicating possible infection by external pathogens of green color morph, which might be caused by high temperature. These results suggested that the optimum temperature for culture of the three color morphs was approximately 18 C, the purple had a better adaption to high temperature, and the green and white color morphs may be more susceptible to thermal stress than the purple color morph.     

Effects of Mosquitofish,Gambusia affinis,on Channel Catfish,Ictalurus puncatatus,Production Ponds

Mosquitofish, Gambusia sp., have been spread throughout the world to biologically control mosquitoes. However, the fish has gained a reputation as an invasive species and has been implicated in displacing native aquatic species. Gambusia affinis are native to the southeastern United States and commonly occur in commercial channel catfish, Ictalurus punctatus, production ponds. We investigated effects of mosquitofish presence on zooplankton populations, water quality, disease occurrence, and fish production in experimental ponds. There were no differences between ponds with or without mosquitofish in numbers of calanoid copepods, cyclopoid copepods, total copepods, Bosmina sp., Ceriodaphnia sp., Moina sp., Daphnia sp., or total cladocerans. There were also no differences in copepod and cladoceran sizes. Copepod nauplii were more numerous during the summer months in ponds with mosquitofish. There were no differences in water quality variables (soluble reactive phosphorus, nitrate, nitrite, ammonia, total nitrogen, total phosphorus, pH) or phytoplankton density between ponds stocked with and without mosquitofish. Catfish production and disease occurrence were also similar between ponds with and without mosquitofish. Although mosquitofish may cause problems when stocked outside their native range, there does not appear to be any adverse effects of mosquitofish presence in catfish production ponds.     

Age,growth, maturity and the overfishing of the iconic sciaenid,Argyrosomus japonicus,in south-eastern,Australia

Mulloway (Argyrosomus japonicus) occur in estuarine and coastal waters surrounding Australia, Africa, India, Pakistan, China, Korea and Japan, where they are important in fisheries. This study identified that mulloway in south-eastern Australia had similar growth rates, but matured at smaller lengths and younger ages, to those in South Africa and Western Australia. Growth of both sexes was similar to about 5 years, after which females grew faster and attained a greater maximum length than males. Female mulloway matured at 4–5 years of age with a L₅₀ of 68 cm, whereas males matured at 2–3 years of age with a L₅₀ of 51 cm. The commercial fishery in New South Wales was characterised by declining catches and a reduction in the proportion of mulloway of mature lengths in landings. During 2002–2005 commercial landings were dominated (83%) by fish within 15 cm of the current minimum legal total length of 45 cm and aged 2 and 3 years (>80%), even though mulloway can attain lengths of 200 cm and live >30 years. Estimates of the rates of instantaneous total mortality ranged between 0.34 and 0.45, whilst the rate of instantaneous natural mortality (M) was estimated to be approximately 0.12. Yield-per-recruit analyses indicated that mulloway in New South Wales are being growth overfished and substantial increases in yield could be achieved by increasing the length at first harvest. Values of the spawning potential ratio were below 0.2 under a range of mortality estimates, suggesting that mulloway are at risk of recruitment overfishing. These results suggest that the spawning stock of mulloway in south-eastern Australia has been depleted and that remedial management action is required to protect this iconic species.     

Recruitment strategy of swimming crab, Portunus trituberculatus, in Hiuchi-Nada, Japan

The recruitment strategy of swimming crabs, Portunus trituberculatus, was investigated by field observations and numerical experiments in Hiuchi-Nada, Japan. Calculated dispersal patterns of zoeal and megalopal stages in a three-dimensional numerical model reproduce observed patterns accurately. The temporal change of vertical migration patterns between the 1st and 2nd zoeas and the 3rd and 4th zoeas plays an important role in the process of recruitment of P. trituberculatus from spawning ground to nursery ground.     

Effect of transfer time,temperature, and size on burrowing capacity of juvenile clams,Mulinia edulis,from hatchery

Studies under laboratory and field conditions have shown that juvenile Mulinia edulis clams measuring 5–15 mm are able to tolerate transfer times of over 24 hr and burrow successfully. Burrowing generally followed an asymptotic curve over time, with a rapid initial phase for smaller juveniles, which slowed over time. In laboratory conditions, at low temperatures (8°C), juvenile burrowing was initially rapid (50–70% at first 2 min). In summer temperatures (15.5°C), the burrowing capacity of three sizes of juvenile clams was tested. Size determines differences in burrowing dynamics, where juveniles of 8.9 mm shell length (SL) take longer to burrow than smaller juveniles (4.9 and 6.3 mm SL). For longer transfer times in laboratory conditions (>12 hr), burrowing was slower. The results indicate a faster burrowing rate in smaller (<10 mm) juvenile clams than in larger ones. Transfer times over 24 hr in field experiments show burrowing levels of over 50% after a 60‐min evaluation, with larger juveniles (>10 mm) requiring longer for burrowing. Based on our results, we suggest sending seeds out to grow in natural environments at SL <10 mm, temperatures below 12°C, and transfer times shorter than 12 hr. These results are valuable for improving future transfer techniques from hatchery to growout for small‐scale aquaculture of this new native species in South America.     

Effects of dietary supplementation of carotenoids on survival, growth, pigmentation, and antioxidant capacity of characins, Hyphessobrycon callistus

This study aimed to find out if dietary carotenoid (CD) supplement could make differences in survival, growth, pigmentation, and antioxidant capacity of characins Hyphessobrycon callistus, an ornamental fish. Two types of CD and its combination (AX — astaxanthin, BC — β-carotene, MX — 1:1 combination of AX and BC) at three concentrations (10, 20, and 40 mg/kg) were used resulting in nine pigmented diets. A diet without CD supplement served as control. No differences in growth and survival of the fish among treatments were found after 8 weeks rearing. Disregarding the types of dietary CD, AX dominated (> 98%) the body CD, indicating that this fish converted most dietary BC into body AX for storage. Body AX and BC content increased with increasing dietary CD concentration. Body AX in BC-fed fish was lower than that in both AX- and MX-fed fish. No difference in body AX was found between AX- and MX-fed fish, and in body BC in all pigmented fish. Serum total antioxidant status [TAS], serum antioxidant enzymes (superoxide dismutase [SOD], glutathione peroxidases [GPx]) and serum transaminases (alanine aminotransferase [ALT], aspartate aminotransferase [AST]) were chosen as indices of fish antioxidant capacity. Antioxidant activities changed with dietary CD type and concentration. Pigmented fish had lower SOD, GPx and ALT than control fish; dietary CD types only affected SOD and ALT in fish. AX-fed fish had the lowest SOD. Dietary AX had more numbers of negative correlations with antioxidant parameters in fish than BC.