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海洋微塑料污染已成为全球性环境问题,生物体内微塑料污染水平是评估其生物效应的基础。本研究以象山湾为例,研究了10种常见海洋生物(贝类、头足类、甲壳类和鱼类)的消化道、鳃和肌肉等组织内微塑料污染状况。结果显示,微塑料广泛存在于各种生物的消化道和鳃等组织内,在61.0%的生物个体内共检出131个微塑料,平均丰度为(1.3±1.5)个/个体;其化学成分包括人造丝(RY; 74.0%)、聚对苯二甲酸乙二醇酯(PET; 14.5%)、聚丙烯(PP; 3.8%)和聚酰胺(PA; 3.1%)等9种类型。检出纤维状、碎片状和颗粒状3种形状的微塑料,分别占95.4%、3.1%和1.5%;所有检测物种中均出现人造丝和纤维状微塑料。微塑料粒径在110~4796 μm之间,平均为(1246±1119) μm,以≤1000 μm的微塑料占比最高(55.2%)。养殖设施产生的典型泡沫状微塑料或聚乙烯(PE)、聚丙烯和聚苯乙烯(PS)塑料类型在生物体内出现频率和丰度较少。研究结果可为深入认识近海生物体内微塑料污染特征及其生物效应提供科学依据。 相似文献
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塑料制品被广泛应用于农业、工业和医疗等众多领域,由此产生的塑料垃圾,特别是粒径小于5 mm的微塑料在海洋中不断累积。微塑料因其粒径小、分布广等特点,对海洋生态系统造成巨大的威胁;其还可沿食物链进行传递,进而对人类健康产生潜在的危害,因此,海洋微塑料污染已成为国内外备受关注的环境问题。从海洋微塑料来源和污染现状入手,综述了微塑料对海洋浮游生物、甲壳类、贝类、鱼类和其他海洋生物的影响,重点关注了微塑料与其他污染物的复合毒性效应等,并在此基础上,提出了未来研究的参考方向,以期为进一步研究微塑料对海洋生物的影响提供理论依据。 相似文献
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微塑料作为一类新兴污染物,已被证实,浓度过高会危害海洋生物的健康,而舟山团鸡山岛垃圾填埋场是一个潜在的微塑料的污染源,若管理不善导致微塑料泄露,可能会对舟山网箱养殖的发展及海水环境造成极大威胁。基于此,本文通过建立模型,研究当团鸡山微塑料泄露后,微塑料的迁移特性及分布规律,同时分析可能对舟山渔业带来的影响。研究表明,微塑料的迁移将受到季节性洋流和季风的作用,存在明显的季节分布规律和迁移特性。其浓度分布除大量聚集在释放点附近外,还会聚集在舟山岛与宁波之间的深水航道中,春季、夏季、秋季和冬季深水航道中的微塑料占比分别为38%、36%、44%和42%。在冬季,大概2%的微塑料会进入到象山湾,对象山湾的网箱养殖带来一定影响。此外,本文探讨了微塑料的分布与海洋锋面的关系,研究表明,锋面会阻止微塑料向外扩散而聚集在近海。本研究将有助于深入了解近海微塑料污染,同时为微塑料污染的控制提供理论依据。 相似文献
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微塑料污染和养殖尾水超标排放已成为全球重要问题。在同一系统中,同时研究丝状藻对氮、磷的去除效果和对微塑料的拦截效果尚未见报道。为解决这一问题,本研究构建了一种藻类净水除杂系统,并研究其拦截微塑料和去除水体氮、磷的能力。研究使用水绵(Spirogyra)、浒苔(Enteromorpha)和刚毛藻(Cladophora)3种丝状藻在净水除杂系统中进行微塑料拦截实验,结果显示,实验时间为10 d时,3种丝状藻对纤维状微塑料拦截效果最佳(水绵88.50%,浒苔79.50%,刚毛藻75.50%),对颗粒状微塑料拦截效果最差(水绵67.50%,浒苔53.00%,刚毛藻55.00%)。与其他2种藻类相比,水绵对微塑料具有更好的拦截效果,因此,使用水绵进行水体氮、磷去除实验。将单位面积的藻量分为0、2、4和6 g/dm2,在15 d的实验中,水绵对总氮的去除率最高为91.88%(4 g/dm2),对总磷的去除率最高为90.33%(6 g/dm2),对PO43--P去除率最高为90.38%(6 ... 相似文献
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为揭示上海松江地区河道微塑料的分布规律和影响因素,利用表层现场采样、密度悬浮法分离、光学体式镜和拉曼光谱结合的观察分析方法,研究了上海市松江区4条流经不同功能区的河道水体中微塑料的含量、粒径范围、来源及影响因素。结果表明,松江地区4条河道中微塑料含量为2~5个·m-3,微塑料含量与河道水径流量成线性负相关(R2=0.81,P<0.05),水流较缓的河道微塑料更容易停留在水体中。河道中微塑料粒径在0.5~5.0 mm范围内,粒径较大,属于刚形成的微塑料。微塑料主要来源于人类生活塑料垃圾和工农业生产中的塑料包装。研究结果可为分析城市河道微塑料污染现状提供参考,并为进一步防控城市微塑料污染打下基础。 相似文献
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针对我国海岸带环境中微塑料监测方法缺乏标准化和系统化问题,探讨和改进了直接浮选法(方法 A)、分液漏斗法(方法 B)和容量瓶法(方法 C)3种典型的潮滩沉积物微塑料检测方法,并探究了沉积物粒径和聚合物类型对其分离效果的影响。经检验,3种方法对潮滩沉积物中尺寸约为1 mm的高密度聚乙烯(HDPE)、聚氯乙烯(PVC)和聚丙烯(PP)等5种常见聚合物颗粒的平均分离效率达到(91±7)%,且聚合物类型并不会影响分离效果(P0.05)。方法 B在分离效率和稳定性方面明显优于其他2种方法(P0.05),对于粗砂(0.5~1.0 mm)、粉砂(0.004~0.063 mm)和泥质(0.004 mm)3类潮滩沉积物中的微塑料颗粒均有着良好的分离(95%±3%)。沉积物粒径会显著影响提取效果,呈现出随着沉积物粒径的增大、微塑料分离效率提高的趋势(P0.05)。利用方法 B对系列现场调查样品进行了测定,结果显示,海州湾北部绣针河口、赣榆港码头和高公岛乡潮滩沉积物中微塑料数量丰度分别为34.97~144.33 n/kg、43.70~119.9 n/kg和372.98~1 103.02 n/kg;质量浓度分别为2.56~10.70 mg/kg、1.01~5.92 mg/kg和3.36~8.48 mg/kg。 相似文献
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《海洋渔业》2021,43(4)
微塑料因其性质稳定,自然条件下难以降解,并能够在风力和洋流的作用下实现远距离输送,已成为海洋中广泛存在的污染物,从表层海水到深海沉积物中均有微塑料被检出。海洋中的微塑料不仅可被生物摄食,随着食物链的传递危害海洋生态系统健康,还对环境中的污染物有吸附作用,并可作为一个新的生态位为微生物提供定殖空间。基于国内外已有的研究成果,总结了微塑料在典型海洋生物体内的分布规律及其影响因素,并归纳了微塑料的毒性效应,诸如对生物体生理机能、氧化应激、免疫应答、神经毒性和繁殖遗传等的毒性,阐释了微塑料致毒机理,包括微塑料作为异物入侵生物体后因其颗粒效应所产生的毒性、微塑料产品中添加剂在环境中的释放,以及由于微塑料对环境中各种污染物质的吸附而产生的复合毒性。最后探讨了微塑料研究方法存在的问题,指出成熟完善的微塑料研究系统与标准的重要性,提出未来毒性暴露实验设计需更贴近真实环境,可为今后微塑料的相关研究提供思路和参考。 相似文献
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随着海洋微塑料污染的日益加剧,长山列岛附近海域生物体内微塑料的分布现状亟待研究。本文研究了长山列岛附近海域7种常见海洋野生鱼类的胃肠道和肌肉中微塑料的污染情况。结果显示,在鱼类肌肉中并未检测到微塑料的存在,微塑料普遍存在于鱼类胃肠道中,其丰度范围为0.19～3.79个/个体;微塑料的尺寸以<300μm为主,占微塑料总丰度的85.91%;微塑料的形状以纤维为主,其次为碎片和颗粒;微塑料的颜色大多为透明色;在鱼类胃肠道中检测到的聚合物类型为赛璐玢(Cellophane)、纤维素(Cellulose)和聚乙烯(Polyethylene),其中,以赛璐玢为主要类型。研究结果为探明微塑料对海洋生态环境中鱼类生物效应提供了基础数据和科学依据。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
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In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 相似文献
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Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
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Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
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