大连湾、辽东湾养殖水域有机氯农药污染状况

采用毛细管GC ECD法测定大连湾、辽东湾表层沉积物及表层、微表层海水中 16种有机氯农药 (OCP16 )的含量。结果表明 ,辽东湾海区表层海水OCPs平均质量浓度为 4 1.94ng/L ,显著高于大连湾海区 4 .5 2ng/L的平均值 ,但 2个湾OCPs质量浓度均未超出渔业水质标准。辽东湾表层沉积物OCPs平均质量分数为 10 .15ng/g ,也明显高于大连湾表层沉积物 6.17ng/ g的平均水平。表明辽东湾有机氯农药污染程度较大连湾重。大连湾各站位微表层海水OCPs含量显著高于表层水 ,显示微表层海水对OCPs有较强的富集作用 ,平均富集系数为 5 .1～ 15 .4。     

福建东吾洋海域海水和沉积物菌群结构及其与环境因子相关性

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...     

Evaluation of resistance to Dermo in eastern oyster strains tested in Chesapeake Bay

We investigated growth, Dermo disease, and survival for nine groups of oysters, Crassostrea virginica (Gmelin) cultivated in Chesapeake Bay (CB). Five regional strains (upper CB, North Carolina (NC), South Carolina (SC), Louisiana (LA) and LA triploids) and four additional hybrid strains (CB oysters mated with NC, SC, LA and Texas (TX) oysters) were held in floating rafts at three locations representative of lower CB: ‘low’ salinity (3–14 g L^?1), ‘moderate’ salinity (5–20 g L^?1) and ‘high’ salinity (14–24 g L^?1). At each site, patterns of growth and incidence of infection with Perkinsus marinus (Levine), the causative agent of Dermo disease, were similar. However, mortality trends were markedly different at each site; the CB strain being notable for accelerated mortality following infection with P. marinus. In addition, hybrids between CB and all four of the regional strains exhibited similar accelerated mortality in response to infection. Mortality was strongly correlated with infection only at the high salinity site implicating interaction of differences in both oyster strain and virulence of Dermo between moderate and high salinity areas as factors in differential mortality across sites.     

Sequence and polymerase chain reaction–restriction fragment length polymorphism analysis of the large subunit rRNA gene of bivalve: Simple and widely applicable technique for multiple species identification of bivalve larva

ABSTRACT:   One of the biggest and long-standing difficulties in investigation of larval ecology in the field is species-level identification. In the present study, we developed polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) analysis based on the large subunit (LSU) rRNA gene (rDNA) D1/D2/D3 region for identification of multiple species of bivalve larvae using 14 species of bivalve collected from Maizuru Bay. The LSU rDNA D1/D2/D3 region of all analyzed species could be amplified by PCR using bvD1f/bvD3r primers, and RFLP analysis by Hae III digestion on the PCR products showed species-specific fragment patterns. Furthermore, this analysis applied to single bivalve larvae in Maizuru Bay revealed efficient amplification of the target region and the species-specific pattern from 80% of the larvae, 75% of which showed a pattern that matched a certain pattern of the adult bivalves. In addition, the analysis of inter- and intraspecies variation of the LSU rDNA D1/D2/D3 region using the sequence data of the genus Crassostrea from the DDBJ database showed high applicability of this RFLP analysis on closely related species. Because of the wide applicability and technical simplicity, this method can become the standard for the identification of bivalve larvae species once the sequence data of the LSU rDNA D1/D2/D3 region of many bivalve species have been accumulated.     

我国海湾扇贝养殖现状、问题与发展对策

据统计,到１９９８年我国海湾扇贝养殖面积发展到近７０００ｈｍ＾２,养殖产量约３０万ｔ。特别是自１９９７年栉孔扇贝养殖出现大面积死亡以来,海湾扇贝养殖面积不断扩大。但在１９９９年贝苗中间暂养阶段发生了大量死亡,造成养殖苗种严重不足,使养殖面积减少约２／３,经济损失惨重。作者就海湾扇贝养殖中存在的问题进行了分析,并对今后的发展提出了一些设想。     

芝罘湾养殖日本长海带试验

报道了日本长海带在烟台市芝罘湾养殖试验情况,日本长海带与烟台市养殖品种和野生品种的外部形态不同,且生长速度快,生长期长,成熟晚。试养证明可以在芝罘湾养殖。在海带育种方面有较高的利用价值。     

乳山湾菲律宾蛤仔养殖滩涂老化修复实验研究

根据乳山湾贝类养殖滩涂老化的特点,采用了压沙1、3cm和翻耕20、40cm的物理修复方式,经过9个月的养殖实验,结果表明,压沙1cm贝类生物量为4．9kg／m^2,压沙3cm贝类生物量为5．6kg／m^2,翻耕20cm贝类生物量为4．6kg／m^2,翻耕40cm贝类生物量为3．9kg／m^2,对照组贝类生物量为4．1kg／m。。除翻耕40cm修复方式外,其他3种修复方式均显示一定的效果,并以压沙3cm最好。翻耕20cm虽然不如压沙的效果好,但与对照组相比仍然显示较大的优势,每亩约增产330kg余。由于翻耕的修复方式操作简单,成本低,容易推广。     

Water quality upstream and downstream of a commercial oyster aquaculture facility in Chesapeake Bay,USA

Oyster aquaculture is an expanding industry in the Chesapeake Bay. Oysters remove nitrogen (N) and phosphorus (P) from the water column through filtration and conversion of phytoplankton into shell and tissue, but also continuously excrete these same nutrients back into the water column as inorganic compounds readily available for plant or algal uptake. The objective of this study was to assess multiple water quality parameters upstream and downstream of a commercial oyster aquaculture facility in the mesohaline region of the Chesapeake Bay. Results of the study indicated a 78.4% average increase in total ammonia nitrogen (TAN) concentration and a 19.4% decrease in chlorophyll-a (Chl-a) concentration downstream of the facility. There was no significant change in the concentration of reactive phosphate (RP), nitrate–nitrogen (NO₃⁻–N), or nitrite–nitrogen (NO₂⁻–N) as water passed through the facility. It was determined that velocity of water through the facility had no influence on the change in TAN or Chl-a concentration from upstream to downstream of the facility. Increased reduction in Chl-a concentration from upstream to downstream was related to higher upstream concentrations of Chl-a. There was no correlation between increased rates of Chl-a removal and downstream TAN. Results of this study suggest that oyster aquaculture can significantly increase the amount of available inorganic nitrogen in the water column immediately downstream of a facility, independent of upstream availability of phytoplankton and flow velocity of water through the facility.     

“海山仙馆”相关历史画卷的识读

古人云"诗画不分家",由此引申诗画与园林同在。"诗"近似造景的理论线索或景观题咏,"画"犹如园林的设计构思、施工造景的蓝本或效果图案。研究行商园林"海山仙馆"遗址地带历代相关画卷,有益于深刻体验该园所富有的诗情画意、追寻其自然与人文空间的艺术境界、探讨口岸城市构园特色的演进规律。     

贡湖湾北部退渔还湖区水、沉积物和土壤中氮的时空分布

太湖贡湖湾北部退渔还湖区(2.18 km2)的水陆交错带,虽已进行了基底改造和小部分植物种植,但仍需开展大规模种植,故迫切需要了解其生境特性的状况,为此开展了该区域的水陆交错带水、沉积物、土壤中氮的时空分布特征调查,以便为后续示范工程的设计提供基本参数。选择南部和北部两处交错带(面积分别为6700、8300 m2)及其周边陆域、水域,分别在2012年11月和2013年5月采集17个点位的水、沉积物和土壤样品,分析了其氮的时空分布。结果表明:水、沉积物和土壤样品中的氮存在明显的季节变化,春季水、沉积物和土壤中的总氮和氨氮均低于秋季,而春季沉积物和土壤中硝氮含量较高。人为栽种植物有利于氮的去除,温度和微生物的活动对此也有一定的贡献。在春季,水陆交错区的硝化作用更强烈;氨氮的空间分布与总氮基本一致,水中氮的主要存在形式是氨氮,而沉积物和土壤中的氮以有机氮为主。