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硬壳蛤(Mercenaria mercenaria)又称小圆蛤、北方帘蛤或美洲帘蛤,是分布于美国大西洋沿岸浅海和滩涂主要的经济双壳贝类之一。其营养和经济价值较高,贝壳又可作为高级工艺品、装饰品的原料。硬壳蛤对低盐和高温的耐受力较强,适宜生活地质广泛,适合在我国开展增养殖,以有效利用我国的滩涂和池塘资源,改善池塘虾、贝混养生态条件,提高池塘 相似文献
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硬壳蛤隶属瓣鳃纲、真瓣鳃目、帘蛤科,又称小圆蛤、北方帘蛤或美洲帘蛤。原分布于美国东海岸,是美国大西洋沿岸浅海和滩涂主要的经济双壳贝类之一。它个体大、肉质鲜美、营养丰富。硬壳蛤为广温、广盐性贝类,能在沙底、沙泥底、泥底和海岸床等多种底质的滩涂和浅海上正常生长、发育,具有较快的生长速度,一年即可达到性成熟。我国与硬壳蛤自然分布的地理纬度相近,自然条件能满足其生长发育需要,因此适合在我国开展增养殖。莆田市水产科学研究所2005年12月从山东引进硬壳蛤,在莆田市秀屿区北江围垦开展规模化土池人工育苗及养殖技术开发研究, 相似文献
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菲律宾蛤仔养殖水体中大肠杆菌安全限量的研究 总被引:1,自引:0,他引:1
研究了在不同大肠杆菌含量的养殖水体中菲律宾蛤仔对大肠杆菌的富集情况,结果是,菲律宾蛤仔对大肠杆菌的富集量随着大肠杆菌在养殖水体中含量的升高而增大,从而推导出富集量公式y=0.9254x2 17.366x-123.77。参照CAC、91/492/EEC和NSSP的标准,通过相关换算,再与国内标准进行对比,建议将菲律宾蛤仔养殖水体中大肠杆菌的安全限量定为≤70MPN/100mL,将供生食的菲律宾蛤仔养殖水体中大肠杆菌的安全限量定为≤14MPN/100mL。 相似文献
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采用固相萃取的方法提取海水中的蛤毒素(Pectenotoxins,PTXs).从2006年7月28日~8月29日,将含有吸附剂的吸附盘片置于黄海胶州湾取样点(36°12.428'N,120°17.826'E)水面以下3 m处,每次放置4d后取出.吸附盘片中的蛤毒素用甲醇洗脱,洗脱液蒸发浓缩近干,用1 ml80%甲醇溶解,然后以液相色谱-串联质谱分析.串联质谱采用电喷雾离子原(ElectroSpray Ionization,ESI)阳离子模式.样品分析所用分离柱为Waters XTerra C18柱(50×2.1mm,3.5 μm),预柱为C18(10×2.1 mm,3.5 μm).流动相A为2 mmol/L甲酸铵、50mmol/L甲酸溶于95%的乙腈;流动相B为2 mmol/L甲酸铵、50mmol/L甲酸溶于纯水.流速为0.4 ml/min,淋洗梯度为0~11min,35%A~100 %A;在11~16.5min,100%A;在16.5~17.0 min,100%A~35%A.分别给出海水中蛤毒素PTX-2、PTX-2 SA、7-epi-PTX-2 SA、PTX-11、PTX-12a和PTX-12b的质谱图.结果发现,这一海域海水中存在蛤毒素PTX-2、PTX-2 SA和7-epi-PTX-2 SA,不存在蛤毒素PTX-11、PTX-12a和PTX-12b.海水中蛤毒素PTX-2、PTX-2 SA与7-epi-PTX-2 SA之和的最大峰值出现在8月1日.然后,蛤毒素浓度逐渐降低. 相似文献
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菲律宾蛤仔Ruditapes philippinarum,隶属于瓣鳃纲、真瓣鳃目、帘蛤科,俗称蛤仔、砂蛤、花蛤、蚬子、砂蚬子。是佩带、热带海洋贝类,在我国分布于南北沿海,其中辽宁、山东的资源较丰富。在广东以汕尾港的分布密度最大, 相似文献
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<正>硬壳蛤(Mercenaria mercenaria Linnaeus)是我国近年来从美国引进的双壳贝类,隶属瓣鳃纲、真瓣鳃目、帘蛤科,又称小圆蛤、北方帘蛤或美洲帘蛤。它个体大、肉质鲜美、营养丰富。硬壳蛤为广温、广盐性贝类,能在沙底、沙泥底、泥底和海岸床等多种底 相似文献
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Brett R. Dumbauld Jennifer L. Ruesink Steven S. Rumrill 《Aquaculture (Amsterdam, Netherlands)》2009,290(3-4):196-223
Aquaculture is viewed as a potential mechanism to meet the growing demand for seafood around the world. The future of bivalve shellfish aquaculture in the U.S. hinges on sustainable practices on the part of industry and a more consistent regulatory regime. Bivalve shellfish aquaculture is a recent practice relative to its history in other countries, beginning in the late 1800s along the U.S. West Coast where it is now well established with farm raised product utilizing land-based hatcheries and grow-out directly in numerous estuaries. Bivalve shellfish aquaculture can be viewed as a disturbance which modifies the estuarine system in three ways: 1) changes in material processes — bivalves process food and produce wastes; 2) addition of physical structure — aquaculture introduces the cultured organisms and in some cases a physical anchoring structure; and 3) pulse disturbances like harvest and bed maintenance disturb sediments, remove species in addition to the cultured organisms themselves, and change resource or habitat availability. In U.S. West Coast estuaries, water column and sediment nutrient concentrations are relatively high and influenced by large tidal exchange and proximity to deeper nearshore ocean waters where upwelling controls production during summer months. Bivalves are unlikely to influence material processes except at local bed scales in these systems, although estuary-wide effects could appear as the fraction of cultured area rises or in poorly flushed bays. Bivalve culture clearly modifies estuarine habitat at local community and at landscape scales and effects are most often evaluated against existing structured habitat in the form of submerged aquatic vegetation. Individual activities act as pulse disturbances and the recovery of eelgrass (Zostera marina) to pre-disturbance levels is variable (< 2 to > 5 years). The extent of disturbance depends on the aquaculture practice and the distribution of eelgrass reflects a balance of space competition, pulse disturbance and recovery, and is therefore at dynamic equilibrium on aquaculture beds. Structure provided by aquaculture appears functionally similar to eelgrass for small benthic infauna and mobile epibenthic fauna while use of aquaculture as habitat by larger more mobile invertebrates and fish depends on mobility and varies with life-history stage and taxon being evaluated. Scale seems a very important management consideration and further research at estuarine landscape scales, especially for habitat use by important invertebrates and fish, may prove useful in designing and implementing best management practices. Though local and short term effects from aquaculture are clearly evident in U.S. West Coast estuaries, bivalve aquaculture does not remove area from the estuary or degrade water quality like other anthropogenic influences, and thus has not been implicated in shifts to alternate states or reduced adaptive capacity of the larger ecological system. 相似文献
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一种贝类作为水产动物诱食剂的研究 总被引:7,自引:0,他引:7
一种贝类(ASL)不仅蛋白质含量高,氨基酸组成也比较全面,高不饱和脂肪酸含量丰富,甜菜碱含量高达289mg/g。向饲料中添加1%的ASL粉,发现其对金鱼的诱食活性不仅显著高于空白对照组,而且显著高于化十香组;饲料中添加03%的ASL粉,异育银鲫摄食量显著高于对照组,六周增重率比对照组提高33%,这些结果表明ASL作为水产动物诱食剂具有很高的开发利用价值。 相似文献
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过氧化氢诱导紫彩血蛤排放精卵及其胚胎发育的研究 总被引:4,自引:0,他引:4
采用浓度为0.1~10‰的H_2O_2海水处理紫彩血蛤,能诱导其排放精卵,排放率为60%~80%,其中H_2O_2浓度在0.5%~1‰之间时效果较好,排放率高达80%,并且诱导排放时间较短。文章还叙述了紫彩血蛤胚胎发育过程中性腺、精子、卵子以及胚胎发育各期的形态。 相似文献
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环境水中农药残留检测的富集净化过程综述 总被引:2,自引:0,他引:2
环境水中农药残留量极低,远低于仪器的检出限而无法直接检测,其瓶颈在于如何富集水中的目标物。本文综述了近年来环境水中农药残留检测预处理富集与净化技术的研究进展;重点讨论了液-液萃取法中萃取溶剂的选择、振荡方式、浓缩方式、乳化与盐析现象、pH值、提取液的净化等影响因素;固相萃取法中吸附材料的选择及活化过程、穿透体积、过水流量、水分的去除、固相萃取柱的淋洗、目标化合物的洗脱、 pH与NaCl改进剂、洗脱液的净化等影响因素;简要介绍新型富集方法并探讨了其中存在的不足;展望了环境水中农药残留富集净化技术的发展方向。 相似文献
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Hilke Giles Conrad A. Pilditch Dudley G. Bell 《Aquaculture (Amsterdam, Netherlands)》2006,261(1):125-140
Shellfish aquaculture is growing worldwide and previous studies have shown a range of associated environmental impacts. In the Firth of Thames, New Zealand, there are more than 2000 ha of existing and approved farm area with applications pending for approximately another 6000 ha, however, no previous studies have examined the impacts of mussel culture in this region. To determine the impact of a mussel farm (45 ha) in the Firth of Thames we measured sedimentation rates by deploying sediment traps, sediment characteristics by collecting sediment cores and sediment oxygen and nutrient fluxes by deploying benthic chambers in four seasons. Sedimentation under the farm was increased by 106 g m− 2 d− 1 compared to the reference site. Similarly sediments under the farm had elevated organic carbon, nitrogen, chlorophyll a and phaeopigment concentrations indicative of the additional organic input due to bivalve biodeposition. Oxygen consumption was higher under the farm compared to a reference site (1.1-2.1×) but this increase was only significant (p < 0.001) in summer when rates reached 3083 μmol m− 2 h− 1 under the farm. Ammonia release rates ranged from 80 to 319 μmol m− 2 h− 1 and were higher under the farm compared to the reference site in spring (1.8×, non-significant p = 0.588) and autumn (3×, significant p = 0.006) but in summer release rates at the reference site (275 μmol m− 2 h− 1) were 1.4× higher than those under the farm. Nitrate fluxes (3.1 to 21.8 μmol m− 2 h− 1) were significantly (p = 0.001) higher at the farm site. Oxygen and nutrient fluxes generally demonstrated the typical response to increased organic input due to sedimentation from mussel culture. Unusually low nitrogen release rates in summer may indicate enhanced denitrification under the farm. Benthic regeneration at the reference site could supply 74% of nitrogen required by pelagic primary producers whereas under the farm it could account for 94%. This demonstrates the importance of benthic nutrient regeneration in this region and that mussel culture can lead to a redistribution of nutrients. The farm we studied is small and located in a high-energy environment and impacts from larger farms or in areas where biodeposit dispersal is limited are likely to be even more significant and we suggest that site-specific hydrodynamic and biogeochemical conditions have to be taken into account when planning new mussel farms to prevent excessive modifications of nutrient dynamics. 相似文献
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Marrit Caers Peter Coutteau Patrick Sorgeloos 《Aquaculture (Amsterdam, Netherlands)》1999,170(3-4):307-322
The effect of lipid supplementation and algal ration on growth and fatty acid composition of juvenile clams, Tapes philippinarum was investigated. A diet of Tetraselmis suecica was supplemented with a lipid emulsion and fed at a daily ration of 0.5, 1.0 and 1.5% WW DW−1 day−1. A mixed algal diet of Isochrysis galbana (clone T-Iso) and T. suecica (1:1 on DW basis) and starvation functioned as positive and negative control treatments, respectively. T. suecica, which contains eicosapentaenoic acid (20:5n−3) but no docosahexaenoic acid (22:6n−3), was supplemented with 50% (% of algal dry weight) of a 22:6n−3-rich emulsion. Higher growth rates of T. philippinarum were associated with higher T. suecica feeding rations. Lipid supplementation resulted in significantly better growth rates of T. philippinarum at a T. suecica ration of 0.5, 1.0 and 1.5% WW DW−1 day−1. The growth promoting effect of lipid supplementation was significantly reduced during 4 consecutive weeks or by increasing the algal feeding ration. Increasing T. suecica rations were associated with a decrease in the % composition of 22:6n−3 while the 20:5n−3% composition was hardly affected in the total lipids of T. philippinarum. On the contrary, the absolute concentration of 22:6n−3 (μg per gram dry weight, μg g DW−1) in the total lipids of T. philippinarum was similar at all T. suecica rations while the 20:5n−3 concentration significantly increased. The major effect of lipid supplementation on the fatty acid composition of the clams, was a significant increase of the 22:6n−3% composition in the total lipids, polar lipids and triglycerides. In contrast with 20:5n−3, the effect of lipid supplementation on the absolute 22:6n−3 content (μg g DW−1) was more pronounced at a higher T. suecica ration. After a starvation period of 4 weeks, the concentration (μg g DW−1) of all fatty acids was significantly reduced, except the n−7 monoenoic fatty acids (MUFA) and the non-methylene interrupted dienoic fatty acids (NMID). The concentration (μg g DW−1) of the NMID in starved clams and clams fed different diets was similar to the concentration in the initial sample. This indicated that growing spat was actively synthesising NMID and they were selectively retained in unfed animals. The results indicated that either dietary lipid or 22:6n−3 was a growth-limiting factor when T. suecica was fed at a ration of 0.5, 1 and 1.5% WW DW−1 day−1. A selective retention in starved clams and a preferential accumulation in fed clams was observed for 22:6n−3 but not for 20:5n−3 which indicated a greater importance of 22:6n−3 compared to 20:5n−3. 相似文献
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尿素氨化秸秆的应用研究进展 总被引:1,自引:0,他引:1
在描述秸杆营养价值的基础上,提出了尿素氨化秸秆的机理、所需条件以及尿素氨化秸秆对家畜生产性能的影响,并进一步指出了减少氨损失的方法。 相似文献
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This study evaluates the risk posed by trace metals on the culture of bivalves in the Galician coast (NW Iberian Peninsula), which depends on collection of natural seed and larval rearing with natural seawater in hatcheries. With this aim, toxicity tests were carried out with embryos of the commercial bivalves Ruditapes decussatus and Mytilus galloprovincialis, and the toxicity of Hg, Cu, Zn, Cd and Pb was quantified in terms of median effective concentration (EC50) and toxicity threshold, using embryogenesis success as endpoint. The EC50 values ranged from 4 to 10 μg/l for Hg and Cu, from 100 to 300 μg/l for Zn and Pb, and from 400 to 2000 μg/l for Cd. The toxicity of copper and zinc combinations could be predicted using a strictly additive model. Effective concentrations found were compared to measured metal concentrations in the Galician Rias, and to local and international seawater quality criteria, in an attempt to evaluate the risk posed by metals to these commercial species. Zinc and especially copper pollution were found to represent a serious threat in certain areas. Furthermore, local seawater quality criteria recently implemented are, in the case of copper and zinc, two orders of magnitude too high to offer any protection for these sensitive early life stages of bivalves. 相似文献
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行为是动物对外界刺激最直接的反应,是动物最重要的生命特征,其研究是生物学最基础的内容。本文介绍了水生动物行为研究的历史过程、国内外发展现状,分析了水生动物的摄食、繁殖、洄游、亲属识别及群居、栖息地选择等行为,阐述了水生动物行为研究在水产捕捞、资源、养殖中的应用,对未来的研究方向做了展望。水生动物行为的研究对提高水产生物学科研究整体水平具有重要意义,也是今后水生动物研究的基本方向。 相似文献