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我国的海水养殖面积和产量均居世界首位。据统计,2002年我国海水养殖产量达1212.84万吨,海水养殖面积134.475万公顷。其中滩涂贝类产量约占我国海水养殖总产量的19%。本文所指滩涂贝类品种主要为缢蛏、菲律宾蛤仔、文蛤、青蛤、蚶类、牡蛎等。池塘养殖滩涂贝类,就是利用沿海滩涂的虾塘、围垦,或筑堤围塘,进行蓄水养殖。其优点是投资少,风险小,效益高,设施和操作简单,受不利环境的影响小。本文着重介绍利用池塘进行缢蛏、蛤类和蚶类的健康养殖技术。 相似文献
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在泥蚶养殖水体中(1000L)投喂浓度分别为1、5和10g微生态制剂(芽孢杆菌),在30天的投喂期内,采用平板计数法检测底泥中、泥蚶体内的细菌总数和弧菌总数。结果表明,在投喂冻干菌粉后,养殖底泥和泥蚶体内菌群在前7天均呈明显上升趋势,7-30天内缓慢下降。由于芽孢杆菌的抑制作用,弧菌的数量下降,以泥蚶体内的弧菌最明显。芽孢杆菌对养殖底泥和泥蚶体内的细菌菌群影响很大,芽孢杆菌对养殖水体底泥和体内菌群的影响与抗生素具有相近的效果,表明芽孢杆菌作为饲料添加剂可以取代抗生素应用于泥蚶养殖。 相似文献
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2001年12月上旬,福建安海湾南岸滩涂养殖的贝类发生大面积死亡.12月10日,受水头镇人民政府的委托,福建省渔业环境监测站组织技术人员前往安海湾贝类养殖现场进行调查.本次调查采集了泥蚶(Tegillarca granosa)、缢蛏(Sinonovacula constricta(Lamarck))两种养殖贝类样品及养殖埕地的表层底泥样品和埕地上的海水(潮水已退)样品,同时还采集了南安市鸿兴五金制品有限公司和南安市庆昌皮业有限公司的混合排污沟的污水样品及污泥样品,并对样品中的重金属含量进行测定分析.另外还对活体泥蚶、缢蛏体内的寄生虫和病毒进行镜检.现将养殖的泥蚶、缢蛏死亡原因的调查结果作如下分析. 相似文献
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生物净水栅对凡纳滨对虾肠道菌群组成的影响 总被引:3,自引:0,他引:3
利用Illumina Miseq高通量测序技术和生物信息学分析手段,采集传统养殖池塘和添加生物净水栅养殖池塘凡纳滨对虾肠道样品,比较分析两个池塘凡纳滨对虾肠道菌群组成及其多样性。试验结果表明,对照组和试验组凡纳滨对虾肠道测得的可操作分类单元分别为239和296。对照组和试验组对虾肠道样品菌群的物种丰度和优势菌种存在一定差异,试验组和对照组样品细菌Shannon指数分别为2.04、1.80,前者细菌Shannon指数高于后者13.33%(P0.05)。对照组和试验组对虾肠道样品所鉴定出的细菌门类组成基本相似,组成比例存在一定差异,前三大优势细菌门类均为变形菌门、拟杆菌门和软壁菌门,分别占试验组细菌总数和对照组细菌总数的97.56%和98.54%。在优势菌群方面,试验组对虾肠道的优势群为弧菌属、希瓦氏菌属、Cloacibacterium、黄质菌属、红杆菌属,分别占细菌总数的70.83%、18.29%、1.97%、1.38%和1.06%,对照组对虾肠道的优势群为弧菌属和希瓦氏菌属,分别占细菌总数的58.51%和37.67%。本研究分析了两种养殖池塘下对虾肠道菌群结构,试验组对虾菌群丰富度高于对照组,其多样性也高于对照组,这有助于生物净水栅更好地应用于池塘养殖。 相似文献
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宁波地处我国大陆海岸线中段 ,海岸线长达840公里 ,现有潮间带滩涂 1 44万亩 ,0至 - 1 0米的浅海 340万亩 ,具有发展浅海滩涂养殖的良好自然条件。其中滩涂贝类养殖实行生态养殖 ,具有本小利厚、生产稳定、管理方便等优点 ,深受广大农民喜爱 ,已成为宁波市海水养殖的一大热点。1滩涂贝类养殖现状宁波市滩涂面积广阔 ,底质类型复杂 ,包括粉砂质泥、泥质粉砂、淤泥、砂质、岩礁等多种类型 ,可适合多种滩涂贝类的养殖 ,主要的养殖种类有缢蛏、泥蚶、泥螺、文蛤、彩虹明樱蛤、菲律宾蛤仔等。目前主要以管养为主 ,即对养殖涂面进行改良、翻整和播… 相似文献
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福建东吾洋海域是我国刺参(Apostichopus japonicus)吊笼养殖的核心产区,但目前该地区的水域环境现状和环境菌群结构相关研究匮乏。本研究以东吾洋海域东安、马坑、雷江和沙湾4个主要养殖区域为对象,完成了海参养殖高峰期1月的水质环境因子调查和评价分析,采用高通量测序方法完成了水体和沉积物菌群多样性和差异特征菌群分析,解析了环境因子与菌群结构相关性。结果表明,马坑海域的富营养化指数为21.60,属于严重富营养化;东安和雷江海域属于重度富营养,只有沙湾海域处于中度富营养的水平。东安和沙湾海域水质属于轻度有机污染,而马坑和雷江海域属于中度有机污染。高通量测序共获得1 520个操作分类单元(operational taxonomic units, OTUs),归属于28门、57纲、163目、322科、581属。菌群结构多样性分析表明,各区域沉积物的菌群多样性水平均显著高于相应海域水体菌群多样性,且具有较强的空间异质性。沙湾海域环境菌群多样性与丰度最高。PCo A分析表明,沉积物和水体中细菌群落结构差异极显著,水体交换和海域位置对其水体和沉积物菌群结构的影响较大。具有潜在致病性的弧菌... 相似文献
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Recruitment and movement of the hard clam Meretrix lusoria in a tidal river of northern Kyushu,Japan
Yasuhisa Henmi Satoshi Kobayashi Junpei Yamaguchi Masahiro Hashiguchi 《Fisheries Science》2014,80(4):705-714
Size-frequency distributions of Meretrix lusoria, a commercially important bivalve in Japan, were compared among 6 sites in tidal flats of a small river in Kafuri Bay, northern Kyushu, Japan during 2006–2008. In Kafuri Bay, the hard clam resource is strictly managed and mean biomass of this species on the fishing ground (about 1.5 km2) exceeded 1.5 kg m?2 in 2008. Small clams (<5 mm in shell length, SL) were most abundant in the border area between the river and the sea, while large clams (>40 mm SL) were rare there. In contrast, in the lower site of the marine area (site L), most clams were >30 mm SL. These results indicate that small clams move from riverine to marine areas with growth (post-settlement movement). Year-round, very small clams (<1 mm SL) were present and clams that were 2–5 mm SL were very rare, although the spawning season is thought to occur in summer. Probably, the early growth of many new recruits is very slow and most may even be <1 mm SL in the next spring, although some clams grow to >5 mm SL in a short period of time. 相似文献
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Sea lice treatments, management practices and sea lice sampling methods on Atlantic salmon farms in the Bay of Fundy, New Brunswick, Canada 总被引:4,自引:0,他引:4
Proper monitoring of all stages of sea lice is imperative to ensure the strategic timing of treatments. Although sea lice receive close attention and management for production purposes, there are no regulations for the reporting of lice burdens on salmon farms in Atlantic Canada, nor are there officially standardized protocols for conducting sea lice counts in the field. The purpose of this study was to complete a survey of Atlantic salmon farms in the Bay of Fundy, NB, Canada. The survey addressed many aspects of sea lice monitoring and control, including methods for sea lice sampling at the site, types of treatments administered for control of sea lice and management practices and decisions regarding the control of sea lice. A total of 83 surveys were completed from July to December 2002. Twelve of the 60 respondents owned and/or operated more than one site and completed a survey for each of their sites at the time of the interview. The position of individuals surveyed included 48 site managers (representing 63 sites), three site owners (representing 11 sites), eight individuals who were both owner and manager (representing nine sites) and one site veterinarian (representing one site). Surveys were completed on 30 sites from the Limekiln Bay and surrounding areas, 23 sites from Grand Manan Island, 18 sites from Deer Island, six sites from Campobello Island and six sites from Passamaquoddy Bay. Fish farmers, in concert with their veterinarians, generally perform intensive monitoring and control practices. However, there is a continued reliance on emamectin benzoate (SLICE®) for sea lice control on Atlantic salmon farms in the Bay of Fundy, which raises concerns regarding the potential for sea lice to develop resistance to the drug. 相似文献
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2004年5月至2005年4月对胶州湾菲律宾蛤仔(Rudimpes philippinarum)底播增殖区进行了逐月定点采样,将样品带回放于实验室内水族箱暂养,每站随机取样,共对3269个个体进行了基本生物学特性测定,研究了移植底播菲律宾蛤仔的生长、死亡等渔业生物学特性。结果表明,底播增殖菲律宾蛤仔苗种的平均个体质量0.26g、平均壳长11.1mm;底播蛤仔与野生蛤仔在生长规律上基本一致,春末至秋初(4~9月)是其主要生长期;1~3龄期间个体生长速度较快,1~2龄、2~3龄,个体质量分别增长3.88g和4.02g;1~2龄生物量增长最快,2~3龄由于死亡率增大,其生物量增长缓慢;1~3龄蛤仔软体部的生长速度快于贝壳,5~6月是菲律宾蛤仔的繁殖肥育期。根据个体生长特性,3龄为最佳采捕年龄;根据目前的养殖状况,2龄蛤仔已达到商品规格,从生物量上分析,采捕2龄蛤仔收益最高;6月是最佳的捕获时期。蛤仔生长具有明显的季节变化,水温是影响菲律宾蛤仔生长的主要环境因子。[中国水产科学,2006,13(4):642—649] 相似文献
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根据2016年4—11月对烟台四十里湾扇贝养殖区环境的监测数据,分析了四十里湾海域海水基本理化指标及月变化趋势,并采用有机污染评价指数法(A)、营养状态指数法(E)、海水营养状态质量指数法(NQI)以及内梅罗环境质量综合评价指数法对其水环境质量状况进行了综合评价。结果表明:四十里湾扇贝养殖区海水温度、pH和盐度的变化范围分别是10.06~20.00℃、7.85~8.25和29.61~30.31,均适合扇贝养殖;溶解氧(DO)、化学需氧量(COD)以及硫化物均符合海水水质一、二类标准,活性磷(DIP)在10月个别养殖区超出海水水质二类标准,总无机氮(DIN)在4月和10月个别养殖区同样超出海水水质二类标准;5—7月环境质量良好,其他月份出现了不同程度的有机污染以及富营养化现象。总体而言,烟台四十里湾扇贝养殖区水环境质量符合扇贝养殖I类区或II类区的要求,但应注意对养殖区的保护,特别是控制陆源污染物的输入。 相似文献
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The present work investigated the health status of the Manila clam in Ireland, with particular reference to brown ring disease
(BRD) caused by V. tapetis which has been responsible for high mortalities of this bivalve throughout Europe. BRD was diagnosed in Ireland in the 1990s,
causing heavy mortalities in Manila clam stocks in the north-west coast. In the current study, samples of clams from an Irish
hatchery were obtained and screened from two sites, Drumcliff Bay, Co. Sligo and Dungloe Bay, Co. Donegal. Turbellarians and
trematodes with some minor infections were the only parasites observed. Clams were examined for BRD, by analysis of shell
valves for brown ring signs, and for V. tapetis by microbiological methods and by polymerase chain reaction (PCR). BRD was not diagnosed in cultivated clams from either
site. It was, however, diagnosed in residual clams, which had survived the initial outbreak of BRD in the 1990s in Dungloe
Bay. V. tapetis, however was detected in clams from both sites. Additionally, BRD was diagnosed, and V. tapetis isolated, in a once-off sample of clams from Mulroy Bay, Co. Donegal, where clams had been on-grown from imported seed. Minor
heterogeneity at the 16S rDNA gene was observed between some sequenced products from Mulroy Bay and from Drumcliff Bay and
Dungloe Bay indicating that in addition to V. tapetis, a V. tapetis-like strain may have been present in Mulroy Bay. The detection of V. tapetis in asymptomatic clams in Drumcliff Bay and Dungloe Bay may indicate that disease development may only occur when a number
of factors combine to induce disease symptoms. 相似文献
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依据2009年2、4、6、8、10、12月水体生源要素调查资料,对胶州湾湿地水体中总氮和总磷的分布及变化特征进行了分析研究。结果表明,1)胶州湾湿地——大沽河感潮河段沿河道自上而下水体中总氮(TN)和总磷(TP)含量大致呈降低趋势;潮间带区域TN和TP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)胶州湾湿地水体中TN和TP的月际变化明显,其中大沽河感潮河段TN以12月最高,2月次之,8月最低;TP以2月最高,12月次之,4月最低。潮间带区域TN 2~8月呈降低趋势,8~12月呈增高趋势;TP以2月最高,其他月份含量较低且变化不明显。3)胶州湾湿地海水中TN、TP等生源要素主要来自大沽河入海径流,大沽河径流入海对胶州湾湿地海水中生源要素的含量水平和分布趋势产生了显著影响。 相似文献
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利用2011年5月?2012年4月(除冰期12月和翌年1?2月外)在渤海莱州湾逐月由底至表垂直拖网(网孔目160 µm)获得的浮游动物样品,开展小拟哲水蚤丰度分布周年季节变动研究。结果显示,小拟哲水蚤季节变化呈单峰型,7?10月份丰度较高,高峰值出现在8月份;水平分布以湾中部偏东侧丰度较集中,其次为湾口站位,湾顶站位为相对低值区。应用Primer 6.0软件中的BIOENV程序分析发现,小拟哲水蚤总丰度的月变化主要受水温影响、特别是1月前的水温,可能还受黄河径流量的间接影响;水平分布则与盐度、水深关系密切。 相似文献