多毛类动物对多环芳烃的毒性响应及代谢研究进展

多环芳烃可富集在水生生物体内,进而通过食物链的放大作用危害人类,多毛类动物是已知能够蓄积大量多环芳烃的物种,有关多毛类动物解毒代谢酶与抗氧化酶的活性及其基因表达水平作为多环芳烃监测指标的研究已有大量报道,但有关多毛类动物如何代谢蓄积在体内多环芳烃的基础理论研究目前尚处于初步阶段。本研究中,综述了近年来国内外有关多毛类动物对多环芳烃的毒性响应及代谢研究,多毛类动物对多环芳烃的代谢类似于脊椎动物,分为两个阶段,参与第一阶段代谢的酶主要是细胞色素P450酶家族,而尿苷二磷酸葡萄糖醛酸转移酶和磺基转移酶被认为是第二阶段代谢过程中起主导作用的酶类,针对目前研究中存在的问题,提出今后应加强多毛类动物对复合多环芳烃以及低剂量多环芳烃长期暴露的毒性响应研究,同时增强对不同多环芳烃的代谢研究。     

马拉硫磷对双齿围沙蚕乙酰胆碱酯酶和过氧化氢酶的影响

采用浓度梯度污染暴露室内模拟方法,研究了沙蚕暴露于不同浓度有机磷农药马拉硫磷的急性毒性效应,以及低浓度马拉硫磷对双齿围沙蚕乙酰胆碱酯酶（AChE）和过氧化氢酶（CAT）的影响。结果表明,马拉硫磷对沙蚕48、72、96h的LC50分别为71.68、49.21、33.16mg·L^-1,安全浓度为3.32mg·L^-1。在低浓度（0.0018～9mg·L^-1）马拉硫磷中暴露3和6d,沙蚕体内乙酰胆碱酯酶活性受到显著抑制,暴露6d时9mg·L^-1浓度组最高抑制率达88.92%,且乙酰胆碱酯酶抑制率与马拉硫磷浓度对数具有显著的剂量效应。沙蚕CAT活性随马拉硫磷浓度增加表现出先降后升再降的趋势,暴露3d时0.018mg·L^-1浓度组CAT活性最高,6d时0.18mg·L^-1浓度组CAT活性最高,分别比对照组高52.02%和53.42%（P〈0.05）,而浓度达1.8mg·L^-1时CAT活力均显著下降（P〈0.05）。结果显示,沙蚕乙酰胆碱酯酶是较好的滩涂有机磷农药污染生物标记物。     

Polychaete (Spirobranchus giganteus) loading on South African corals

• 1. Spirobranchus giganteus is a ubiquitous serpulid polychaete that is an obligate associate of living coral. At Sodwana Bay, South Africa, it is a conspicuous associate of Acropora clathrata plates.
• 2. This study explores the relationship between S. giganteus abundance and factors hypothesized to represent stress to the corals, in particular coral bleaching, diving intensity and exposure to destructive wave action as a function of depth. In addition, plate size was investigated to increase understanding of habitat selection by S. giganteus.
• 3. There was no significant correlation between diving intensity and S. giganteus abundance on the three reefs studied, suggesting either that the current level of diving intensity causes no stress or that S. giganteus does not indicate stress.
• 4. Depth influenced the size distribution of A. clathrata plates, with the larger plates being at greatest depths (>0.4 m² at depths >14 m).
• 5. Extremely high S. giganteus densities (most plates with number of individuals >50 m^?2; maximum number of individuals 413.63 m^?2 at 9 m depth on one reef) were recorded at depths >14 m, with density increasing overall with depth.
• 6. The high densities of S. giganteus on A. clathrata plates are possibly because the plates are a physically elevated platform above the reef, where factors such as predation, competition and smothering by sand are far less important than on the reef surface. In turn, upwelling of nutrients and dependent plankton may encourage S. giganteus to maintain high population levels.
• 7. Climatic or other stresses are not considered currently to be responsible for these high S. giganteus densities. Rather, the worm data reflect a healthy upwelling, which may change as the coral reef becomes stressed with global climate change.

Copyright © 2005 John Wiley & Sons, Ltd.     

Maturation diet based on fatty acid content for male Penaeus monodon (Fabricius) broodstock

The contents of three essential fatty acids, arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), from wild Penaeus monodon broodstock were evaluated in comparison with natural diet fed P. monodon. Spermatophores of wild male broodstock contained higher levels of AA than those of artificial diet fed males. Polychaetes had higher proportion of AA to EPA and DHA at 5.8:5.5:1 in mud polychaetes followed by 12:7:1 in sand polychaetes, while DHA was a preferential n‐3 highly unsaturated fatty acid (HUFA) in squids and fish. The experimental feed was constructed to simulate the HUFA profile of polychaetes (AA:EPA:DHA as 5:1:1) and then fed to farmed male black tiger prawn broodstock for 1 month. The results exhibited comparable reproductive characteristics to wild male suggesting the possibility of replacing wild males with pond‐reared males. Rearing farmed males in a test unit for a month did not reduce the quality of prawn sperm. Reproductive performance indices (sperm sac weight, total number of sperm, percentage of live sperm, percentage of abnormal sperm) from the males of all treatments were not statistically different except in males fed with pellets. Control (live feeds) and combined diet provided better reproductive performance in pond‐reared males. Analysis of AA, EPA and DHA in reproductive tissues, hepatopancreas and muscle of treated animals in each treatment revealed an accumulation of dietary HUFA into reproductive tissues. No evidence of transfer of HUFA from hepatopancreas or muscle to spermatophore was found.     

多毛类底栖动物在莱州湾生态环境评价中的应用

多毛类底栖动物常作为环境扰动的指示生物.对2011年莱州湾20个站位的多毛类底栖动物群落生态特征及其与沉积物理化特征的相互关系进行了研究,以期应用于莱州湾生态环境质量状况评价.结果表明,莱州湾多毛类共60种,4季平均生物密度为548.7个/m2,平均生物量为2.79 g/m2,机会种种类数量占优势种种类37.5％.种类多样性较高站位主要集中在湾东部,较低站位集中在湾西部和南部.ABC曲线表明多毛类动物处于中等扰动状态.BOPA指数显示,春季,站位S15和S16为中度污染,夏季,S14站位为重度污染.BIO-ENV分析结果显示,5个最佳环境变量组合相关系数ρs＞0.8,表明沉积物理化性质对多毛类动物群落结构的影响是显著的,沉积物粒度是最主要环境因子.因此,可通过多毛类种类、数量组成的时空变化特征及其与环境因子的生态关系,评价莱州湾生态环境质量状况,为环境污染控制和海洋生态环境保护提供基础信息和科学依据.     

Survivorship and tube growth of reef‐building Serpula vermicularis (Polychaeta: Serpulidae) in two Scottish sea lochs

• 1. In the UK, reef formation by the tubicolous polychaete Serpula vermicularis L. has been recorded in only two sea lochs in Argyll, west Scotland. Serpula vermicularis aggregations are now confined to Loch Creran, those in Loch Sween having died out for unknown reasons.
• 2. Survivorship and tube extension rates were measured in situ in order to compare habitat quality of the two sea lochs and to determine the feasibility of artificial restoration of Loch Sween reefs using stock translocated from Loch Creran. After labelling and measurement, clusters of inhabited tubes collected from Loch Creran were re‐planted at two sites in Loch Sween and two in Loch Creran in July 2004, and monitored at intervals before recovery and remeasurement in July 2005.
• 3. In Loch Sween the tube clusters gradually disappeared over the monitoring period. Only remnants were left by May 2005 and no growth data were obtained. In Loch Creran 76% of the labelled tubes were relocated. Confirmed mortality over the year was 5.3% and mean tube extension rate was 33 mmy^?1.
• 4. There was no significant difference in tube growth between the two Loch Creran sites and inter‐individual differences accounted for most of the variability in the data. Individual tube extension declined significantly with worm body mass but mean extension showed no relationship to total worm biomass in each cluster. Annual tube extension rate in Loch Creran was low in comparison with literature data from other serpulids, suggesting that tube growth is strongly seasonal.
• 5. The 10‐month persistence of some living worms in Loch Sween suggests that there is no physiological barrier to survival of stock translocated from Loch Creran but in situ video monitoring would be necessary to determine the cause of tube disappearance.

Copyright © 2007 John Wiley & Sons, Ltd.     

Bait worms: a valuable and important fishery with implications for fisheries and conservation management

Bait is an integral part of coastal life, but is perceived as a low‐value resource as fisheries are data‐limited, locally focussed and largely unregulated even though the ecological impacts of collection are considerable. An empirical assessment of three UK‐based ragworm fisheries combined with an analysis of published literature has produced the first global assessment of polychaete bait fisheries. The five most expensive (retail price per kg) marine species sold on the global fisheries market are polychaetes (Glycera dibranchiata, Diopatra aciculata, Nereis (Alitta) virens, Arenicola defodiens and Marphysa sanguinea). We estimate that 1600 t of N. virens per annum (worth £52 million) are landed in the UK with approximately 121 000 tonnes of polychaetes collected globally valued at £5.9 billion. Using remote closed circuit television (CCTV) cameras to monitor collectors, activity at local sites is considerable with a mean of 3.14 collectors per tide (day and night) at one site and individuals digging for up to 3 h per tide, although intensity differed seasonally and between sites. Collectors removed on average 1.4 kg of N. virens per person per hour, walking a considerable distance across the intertidal sediment to reach areas that were usually already dug. The implications of these human activity and biomass removal levels are explored in the context of fisheries and conservation management. At local, regional and national scales, polychaete bait fisheries are highly valuable, extract significant biomass and have considerable impacts; therefore, they urgently require governance equivalent to other fisheries.