首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 468 毫秒
1.
2002年3月至2003年9月间对福州市近海养殖区菲律宾蛤仔体内的汞、砷、铅、镉、石油烃、多氯联苯、粪大肠菌群、沙门氏菌、副溶血性弧菌、单核细胞增生李斯特氏菌的含量进行调查与分析。结果表明:主要养殖区内的养殖菲律宾蛤仔中的总汞、多氯联苯、沙门氏菌和单核细胞增生李斯特氏菌菌符合国家无公害水产品安全要求标准;个别养殖区生物体内铅、砷、镉、石油烃的含量超标;养殖区养殖生物中的粪大肠菌群、副溶血性弧菌严重超标。  相似文献   

2.
在不同大肠菌群含量的养殖水体中,通过菲律宾蛤仔对大肠菌群的富集研究,发现菲律宾蛤仔对大肠菌群的富集量随着大肠菌群在养殖水体中含量的升高而增大,推导出的富集量公式为y=0.9254x2+17.366x-123.77。参照CAC、91/492/EEC和NSSP的标准,通过相关换算及与国内标准对比,建议菲律宾蛤仔养殖水体中大肠菌群的安全限量定为≤70cfu/100ml,生食菲律宾蛤仔养殖水体中大肠菌群的安全限量定为≤14cfu/100ml。  相似文献   

3.
菲律宾蛤仔净化技术研究   总被引:1,自引:0,他引:1  
研究探讨了用食品级二氧化氯消毒海水净化菲律宾蛤仔的生产工艺。通过L9(33)的3次重复正交试验,以大肠菌群数的杀菌率为指标,摸索出用4倍的消毒海水(二氯化氯的质量分数为8×10-6)在充氧状态下净化菲律宾蛤仔,8h换水1次,净化时间共24h的净化工艺。该工艺经中试能使菲律宾蛤仔肠道的大肠菌群数从4200MPN/100g下降到230MPN/100g,杀菌率达95%左右;砂分从65mg/100g降到23mg/100g;挥发性盐基氮从3.8mg/100g上升到5.8mg/100g,这些指标都满足DB35/575—2004的要求。同时进行了余氯的定性和定量检测,证明净化的菲律宾蛤仔未检出余氯的残留。  相似文献   

4.
营养盐在沉积物-水界面的扩散影响菲律宾蛤仔(Ruditapes philippinarum)的底播、菲律宾蛤仔和鳗草实生苗的互作,推测菲律宾蛤仔规格、丰度和活动稳定性影响营养盐的扩散。将不同丰度、规格的菲律宾蛤仔置入沉积物中,室内培养19天,并于第13、19天,研究营养盐在沉积物-水界面的交换通量。菲律宾蛤仔生物量、规格和丰度、活跃性影响营养盐在沉积物-水界面的交换通量,第13天,NO-2-N、NH3-N、TN交换通量受菲律宾蛤仔规格影响,NO-2-N和NH3-N交换通量随菲律宾蛤仔规格增大而增大。第13天和19天,NO-2-N、NH3-N、TN、PO43--P交换通量受菲律宾蛤仔丰度影响,随菲律宾蛤仔丰度增大而增大。因此,评估滤食性贝类环境容量、贝类与海草的互作时,需考虑贝类生物量、规格和丰度的作用。  相似文献   

5.
为了研究黑石礁海区潮间带底质的粒径组成对菲律宾蛤仔分布的影响,找到最适合苗种底播增养殖的底质,于2005年3月24日对辽宁省大连市沙河口黑石礁海区潮间带进行了底质和菲律宾蛤仔资源的调查。结果表明:在潮间带,越靠近岸边,底质粒径越大。将底质分为Ⅰ、Ⅱ、Ⅲ 3个类型,菲律宾蛤仔分为4个类型,Ⅱ型底质适宜菲律宾蛤仔生活,蛤仔分布最广;壳长2~3 cm的蛤仔对底质要求较低,对底质粒度的适应范围较广。  相似文献   

6.
汉沽养殖菲律宾蛤仔突发性死亡原因调查及分析   总被引:1,自引:0,他引:1  
2012年9—10月,汉沽浅海底播菲律宾蛤仔发生大规模死亡,死亡率最高达86.2%,同时生长缓慢。调查结果显示,蛤仔死亡率随养殖密度增大而升高;海水和沉积物中重金属、石油烃等化学因子均未超标;6—8月叶绿素含量及初级生产力明显偏低;6月中旬出现寻氏肌蛤,9—10月减少、消失,同时蛤仔出现大规模死亡。推测蛤仔死亡原因为底质表层的寻氏肌蛤与蛤仔争夺近底海水中的饵料和溶氧,并通过足丝网络影响蛤仔的摄食及呼吸。较低的海域初级生产力也进一步加剧了蛤仔的死亡。  相似文献   

7.
胶州湾是我国重要的菲律宾蛤仔(Ruditapes philippinarum)养殖基地,为探究湾内菲律宾蛤仔的生态容量及其碳汇功能,本研究采用Ecopath模型法评估了胶州湾菲律宾蛤仔的生态容量,并利用Ecosim模块动态分析了菲律宾蛤仔生物量扩大对胶州湾生态系统结构与功能特征的潜在影响,同时估算了胶州湾菲律宾蛤仔个体及种群水平的碳收支情况。结果显示,胶州湾菲律宾蛤仔的生态容量为239.9 t/km2,虽然整体水平尚未达到生态容量,但局部养殖区域已远超出了菲律宾蛤仔的生态容量;当胶州湾菲律宾蛤仔生物量从当前增加至生态容量时,生态系统总流量、容量、优势度和循环指数分别提高了16.0%、3.9%、47.1%和103.0%,而熵值降低了10.4%,表明此时生态系统具有更高的成熟度与稳定性,但菲律宾蛤仔生物量扩大至生态容量10倍时会对生态系统产生不利影响甚至崩溃;菲律宾蛤仔个体在1个养殖周期内约摄取3 310.1 mg C,其中约46.2%的碳沉降至海底,约13.2%的碳通过收获移出,如按菲律宾蛤仔生物量达到生态容量时计算,胶州湾每年将有1.5万t碳以生物沉积形式沉降至海底,有0.6万t碳以收获形式移出。研究结果为指导菲律宾蛤仔增养殖产业的健康可持续发展、阐明菲律宾蛤仔的碳汇功能提供了理论依据与数据支撑  相似文献   

8.
胶州湾移植底播菲律宾蛤仔的生长和死亡特性   总被引:3,自引:0,他引:3       下载免费PDF全文
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   

9.
为提高冷冻菲律宾蛤仔品质,分别以魔芋葡甘聚糖、壳聚糖及魔芋葡甘聚糖与壳聚糖(1∶1)溶液对菲律宾蛤仔进行被膜预处理后再进行冷冻试验。分析了不同预处理对冷冻菲律宾蛤仔品质的影响规律。结果表明,被膜预处理可有效改善冷冻菲律宾蛤仔品质,降低冷冻菲律宾蛤仔VBN值,提高产品合格率;在相同浓度条件下,以魔芋葡甘聚糖被膜预处理效果最优,并获得到了冷冻菲律宾蛤仔的优化预处理工艺参数。  相似文献   

10.
为探究菲律宾蛤仔对Cd~(2+)、Mn~(2+)、Zn~(2+)、Cu~(2+)的耐受能力,采用毒理学试验方法研究4种重金属离子对菲律宾蛤仔的急性毒性效应。试验结果显示,菲律宾蛤仔的死亡率与4种重金属离子的质量浓度成正比,表现出明显的剂量—效应关系。4种重金属离子对试验菲律宾蛤仔24、48、72、96 h的半数致死质量浓度分别为:Cd~(2+),38.62、29.83、8.11、2.67 mg/L;Mn~(2+),712.58、421.57、188.74、61.27 mg/L;Zn~(2+),141.27、72.20、34.91、21.57 mg/L;Cu~(2+),29.88、12.06、3.62、0.79 mg/L;Cd~(2+)、Mn~(2+)、Zn~(2+)、Cu~(2+)对菲律宾蛤仔的安全质量浓度分别为0.03、0.61、0.22、0.01 mg/L。试验结果表明,4种重金属离子对菲律宾蛤仔毒性强弱依次为Cu~(2+)Cd~(2+)Zn~(2+)Mn~(2+),Cu~(2+)对菲律宾蛤仔的安全质量浓度低于渔业水质标准,在育苗和养殖过程中需特别关注。  相似文献   

11.
Differences in taste and odour between three kinds of clam with the highest aquacultural production in China were investigated. Meretrix petechialis, Mactra veneriformis and Ruditapes philippinarum (fresh and dried product) were analysed firstly by electronic tongue and electronic nose. Fresh and dried clams could be easily distinguished, and there was little difference between uncooked fresh clams, while greater difference occurred between R. philippinarum and other fresh clams after cooking. The total free amino acid (FAA) content of uncooked clams increased after cooking but decreased in dried clam; the highest proportion was of sweet taste FAAs. Ala, Glu, Arg, 5′‐adenosine monophosphate and 5′‐inosine monophosphate were the most important active taste compounds. The umami intensity order was found to be fresh R. philippinarum, followed by M. petechialis and M. veneriformis, and finally dried R. philippinarum. The greatest number of volatile compounds was found in dried clam, while M. petechialis and M. veneriformis had the most compounds in common.  相似文献   

12.
Abundance, length‐frequencies and distribution of Ruditapes philippinarum (Manila Clams) and Tellina (Quidnipagus) palatum were measured at two beaches in Kāne'ohe Bay, O'ahu, Hawai'i in June, 2010. Abundances had decreased from 866.2 m?2 to 3.4 m?2 for Ruditapes and from 75.5 m?2 to 1.5 m?2 for T. palatum since 1977. Distribution of both species was patchy, but both were most commonly found >40 m from shore. Size frequencies of live clams compared with empty shells suggest that few Ruditapes survive to sexual maturity. A similar trend was not detected for T. palatum. Aquaculture trials of R. philippinarum were conducted at the He'eia and Moli'i traditional Hawaiian fishponds in the same bay. The clams failed to thrive, although triploid and diploid Crassostrea gigas performed well in concurrent trials in the same fishponds. Current lower abundances for wild R. philippinarum could be due to factors related to predation or nutrient limitations. Previously, two large sewage outfalls existed at the surveyed clam bed areas which may have temporarily increased nutrient availability for both wild and cultured clams. Current nutrient levels may inhibit Manila clam growth and recruitment in Kāne'ohe Bay.  相似文献   

13.
The metabolic responses of different colour strains of Ruditapes philippinarum in terms of oxygen consumption and ammonia excretion to changes in temperature (15–35°C) and salinity (20–40) were investigated. In our range of temperatures (15–35°C), oxygen consumption rate (OCR) increases in cultivated strains (White and Zebra) in opposition to the effect in the wild strain which reach a maximum at 25°C. The highest Q10 coefficients were 2.741 for zebra strain, 4.326 for white strain, and 1.944 for wild at temperatures of 25–30, 30–35 and 20–25°C respectively. In our range of salinity (20–40°C), OCRs of white strain and zebra strain firstly decreased to lowest level at 25 and 30, and then increased to highest level at 35 and 40 respectively. When the salinity is beyond 35, the OCR decreased and the turning point was found in the white strain and wild, but the zebra strain OCR still increased to a highest level (1.906 mg g?1 h?1) at 40 (< 0.05). These results show that the cultivated colour strains of R. philippinarum were different from wild in terms of metabolic responses, and information on its response to different temperature and salinity have implications in the aquaculture industry.  相似文献   

14.
Short-necked clam (Ruditapes philippinarum) muscle was hydrolyzed with trypsin, and the antioxidant activities of isolated peptides were investigated. The hydrolysate was fractionated by chromatographic methods using Sephadex G-25 gel filtration and Hypersil BDS C18 reversed phase high performance liquid chromatography (RP-HPLC). The antioxidant activities of the hydrolysate were determined by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH), reducing power assay, and the protective effect against hydroxyl-radical-induced DNA damage. The amino acid sequence of the purified antioxidant oligopeptide was found to be Gly-Asp-Gln-Gln-Lys.  相似文献   

15.
The relative contribution of particulate organic matters (POMs) in water column and sediment as a food source for the Manila clam, Ruditapes philippinarum, was studied using carbon and nitrogen stable isotopic method (δ13C and δ15N) in a tidal flat at Seaside Park, Yokohama, Japan. Comparisons of δ13C and δ15N among R. philippinarum and POMs in surface water, bottom water, and sediment surface indicated that R. philippinarum larger than 5 mm shell length (SL) mainly assimilated benthic POM, and individuals smaller than 5 mm SL assimilated benthic and pelagic POM. Continuous measurements of chlorophyll concentrations in the bottom water revealed tide-driven resuspension of the benthic phytopigments. R. philippinarum showed differences in δ13C and δ15N along an inshore–offshore transect, indicating small-scale spatial differences in POM provision in the tidal flat. These findings suggest that POM in the bottom water, supposedly inhaled by R. philippinarum, is a mixture of a larger proportion of resuspended benthic POM and a smaller proportion of pelagic POM, and that the mixing ratio of the POMs may be affected by the hydrodynamics of flooding water associated with tidal flat topography.  相似文献   

16.
Mass selection for shell length was conducted in the orange strain of the Manila clam, Ruditapes philippinarum, in this study. Based on the size‐frequency distribution, the clams constituting the largest 10% of the distribution were selected as parents for the selected line. An equal number of clams of the orange strain were randomly chosen as parents for the control line prior to the size selection. The responses to selection and realized heritability were 2.37 and 0.61, respectively. In addition, 97.3% of the progenies inherited the orange shell color. Our results suggest that mass selection for fast growth of shell length in this orange strain of the Manila clam is effective.  相似文献   

17.
Sufficient high‐quality microalgae are required for indoor nursery of juvenile Ruditapes philippinarum. However, culturing numerous microalgae to support clam feeding is a heavy burden on many hatcheries. The effects of detritus from the macroalgae Ulva pertusa, Chondrus ocellatus and Undaria pinnatifida on the growth, amino acid content and fatty acid profile of Rphilippinarum were assessed as potential substitute diets. The green microalga Tetraselmis cordiformis served as comparative diet. Results revealed that the clams ingesting distinct diets presented no significant differences in growth of soft tissues, but the nutritional component of these clams differed dramatically. The clams fed with Undaria + Tetraselmis had the highest content of essential amino acids and proteins. In addition, the clams fed with single macroalgal diets and mixed macroalgal detritus and Tetraselmis showed significantly higher or statistically equal levels in n‐3/n‐6 ratio and docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) ratio with respect to Tetraselmis diets. The relative percentages of EPA and DHA in clams fed with Undaria were 28% and 63% higher than those fed with Tetraselmis, and the arachidonic acid abundances in clams ingesting Undaria + Tetraselmis and Tetraselmis were significantly higher than those in clams ingesting other diets. Together, the diets containing single Undaria or mixed Undaria + Tetraselmis produced Manila clams with nutritional advantages in terms of essential amino acids and polyunsaturated fatty acids. Thus, the detritus of macroalgae, especially Undaria, is an appropriate substitute diet, at least partially, for culture of nutrition‐improved R. philippinarum.  相似文献   

18.
为改进菲律宾蛤仔垦区育苗技术,设置一口池塘(A)培育高密度浮游植物并定期添加至育苗池(B),未添加藻类育苗池(C)作为对照,比较了A、B、C以及邻近自然海区(D)的水体、沉积物、浮游植物状况和池塘B、C中稚贝生长情况。结果显示,池塘A、B、C之间水质和沉积物各指标无显著性差异,但三者水体中盐度、pH、溶解氧、氨氮、硝酸盐氮、活性磷酸盐和沉积物中有机碳、硫化物与自然海区D差异显著;浮游植物密度ABCD,但仅A、D间差异显著;池塘B稚贝壳长和密度均显著大于池塘C。这表明垦区与自然海区环境差异大,而育苗期间通过外源补充藻类能提高稚贝的生长率和成活率,进而提高菲律宾蛤仔垦区育苗成功率。  相似文献   

19.
基于Ecopath模型的胶州湾生态系统比较研究   总被引:1,自引:0,他引:1  
文章根据2015–2016年胶州湾渔业资源与生态环境调查数据,并收集20世纪80年代胶州湾渔业资源数据,利用Ecopath with Ecosim 6.5(Ew E)软件构建了由21个功能组组成的胶州湾1980-1982年和2015-2016年两个时期的Ecopath模型,比较分析了不同时期胶州湾生态系统结构和功能变化以及系统发育特征。研究结果显示,与1980-1982年生态系统相比,胶州湾2015-2016年生态系统中大型底层鱼类生物量减少,菲律宾蛤仔(Ruditapes philippinarum)生物量提高,渔获物产出以菲律宾蛤仔为主,渔获平均营养级降低,系统能量转化效率从1980-1982年的15.83%提高到2015-2016年的16.35%,能量流动始终以牧食食物链为主。关键种分析表明,胶州湾生态系统两个时期的关键种均为菲律宾蛤仔。此外,与1980-1982年生态系统相比,2015-2016年胶州湾生态系统整体规模增大,净生产量提高5倍,系统总初级生产量与总呼吸量的比值由1980-1982年的1.267提高到2015-2016年的2.518,系统连接指数、杂食指数与Finn’s循环指数和平均路径长度均减小,说明在过去30多年胶州湾生态系统成熟度和稳定性不断降低,发育过程出现由成熟向幼态的逆行演替现象,目前处于不稳定的幼态阶段。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号