CO2协同低温有水对卵形鲳鲹麻醉保活效果的影响

【目的】探究二氧化碳CO₂麻醉协同低温对卵形鲳鲹有水保活的影响,延长卵形鲳鲹(Trachinotus ovatus)的保活时间。【方法】研究保活过程中CO₂质量浓度、麻醉时间、麻醉温度和鱼质量水比对卵形鲳鲹有水保活时长的影响;在最佳麻醉保活条件下,测定其血清生化指标、肌肉及肝脏氧化应激指标及代谢指标。【结果】卵形鲳鲹在16℃、100 mg/L CO₂水溶液中麻醉3 min其麻醉效果最佳。在15℃低温下进行有水保活,鱼水质量比为2∶1,存活时间最长,为(359±2)min,此条件下复苏率达100%。经过CO₂麻醉协同低温有水保活后的卵形鲳鲹血清谷草转氨酶(GOT)活性显著升高(P<0.05)、尿素氮(BUN)和甘油三酯(TG)含量上升,血糖含量下降。肌肉中的乳酸脱氢酶(LDH)活性显著上升(P<0.05),乳酸(LD)和糖原含量上升,过氧化氢酶(CAT)活性和丙二醛(MDA)含量下降;肝脏中的LDH活性显著上升(P<0.05)、CAT活性和LD的含量上升,MDA和糖原的含量下降。【结论】CO₂协同低温有水对卵形鲳鲹有较好的麻醉效果,有助于保活运输。在保活过程中卵形鲳鲹通过提升能量代谢水平和抗氧化能力应答环境应激,在一定程度上影响卵形鲳鲹保活过程的存活时间。     

From microscope to management: The critical value of plankton taxonomy to marine policy and biodiversity conservation

Taxonomic information provides a crucial understanding of the most basic component of biodiversity – which organisms are present in a region or ecosystem. Taxonomy, however, is a discipline in decline, at times perceived as ‘obsolete’ due to technical advances in science, and with fewer trained taxonomists and analysts emerging each year to replace the previous generation as it retires. Simultaneously, increasing focus is turned towards sustainable management of the marine environment using an ecosystem approach, and towards conserving biodiversity, key species, and habitats. Sensitive indicators derived from taxonomic data are instrumental to the successful delivery of these efforts. At the base of the marine food web and closely linked to their immediate environment, plankton are increasingly needed as indicators to support marine policy, inform conservation efforts for higher trophic organisms, and protect human health. Detailed taxonomic data, containing information on the presence/absence and abundance of individual plankton species, are required to underpin the development of sensitive species- and community-level indicators which are necessary to understand subtle changes in marine ecosystems and inform management and conservation efforts. Here the critical importance of plankton taxonomic data is illustrated, and therefore plankton taxonomic expertise, in informing marine policy and conservation and outline challenges, and potential solutions, facing this discipline.     

海洋牧场溶解氧生态模型初探

文中利用黄海沿岸威海小石岛海洋牧场2016年6-11月份和荣成西霞口海洋牧场2016年6-10月份海洋牧场海底观测网实时高频温、盐、深、溶解氧、叶绿素浓度等水环境数据对牧场的海底环境进行季节变化分析和日变化分析,并利用自由水域假设建立溶解氧生态模型,对两个牧场的生态系统新陈代谢参数进行计算并分析,得到其GPP,R和NEP的月变化趋势,并结合实测溶解氧数据和海底视频,对生态系统稳定性较差的西霞口海洋牧场进行合理建议。研究还发现对于这两个浅水动物养殖型海洋牧场,物理过程对溶解氧变化的贡献和生物过程相当。     

Biological,physical and chemical properties at the Subtropical Shelf Front Zone in the SW Atlantic Continental Shelf

The physical aspects of the Subtropical Shelf Front (STSF) for the Southwest Atlantic Continental Shelf were previously described. However, only scarce data on the biology of the front is available in the literature. The main goal of this paper is to describe the physical, chemical and biological properties of the STSF found in winter 2003 and summer 2004. A cross-section was established at the historically determined location of the STSF. Nine stations were sampled in winter and seven in summer. Each section included a series of conductivity-temperature-depth (CTD) stations where water samples from selected depths were filtered for nutrient determination. Surface samples were taken for chlorophyll a (Chl-a) determination and plankton net tows carried out above and below the pycnocline. Results revealed that winter was marked by an inner-shelf salinity front and that the STSF was located on the mid-shelf. The low salinity waters in the inner-shelf indicated a strong influence of freshwater, with high silicate (72 μM), suspended matter (45 mg l⁻¹), phosphate (2.70 μM) and low nitrate (1.0 μM) levels. Total dissolved nitrogen was relatively high (22.98 μM), probably due to the elevated levels of organic compound contribution close to the continental margin. Surface Chl-a concentration decreased from coastal well-mixed waters, where values up to 8.0 mg m⁻³ were registered, to offshore waters. Towards the open ocean, high subsurface nutrients values were observed, probably associated to South Atlantic Central Waters (SACW). Zooplankton and ichthyoplankton abundance followed the same trend; three different groups associated to the inner-, mid- and outer-shelf region were identified. During summer, diluted waters extended over the shelf to join the STSF in the upper layer; the concentration of inorganic nutrients decreased in shallow waters; however, high values were observed between 40 and 60 m and in deep offshore waters. Surface Chl-a ranged 0.07–1.5 mg m⁻³; winter levels were higher. Three groups of zoo and ichthyoplankton, separated by the STSF, were also identified. Results of the study performed suggest that the influence of freshwater was stronger during winter and that abundance distribution of Chl-a, copepods and ichthyoplankton was related to the Plata Plume Waters (PPW), rather than to the presence of the STSF. During summer, when the presence of freshwater decreases, plankton interactions seem to take place in the STSF.     

Molecular cloning and β-naphthoflavone-induced expression of a cytochrome P450 1A (CYP1A) gene from an anadromous river pufferfish, Takifugu obscurus

In recent years, there has been a decline in the wild populations of river pufferfish, Takifugu obscurus. Besides overexploitation for commercial purposes, environmental pollution is believed to have contributed to its decline. However, almost no information exists about genes involved in metabolism of xenobiotics by this species. Nevertheless, there is interest in fugu fishes, since they possess the smallest genome among vertebrates. We cloned and characterized the full-length cDNA sequence of a cytochrome P450 1A (CYP1A) gene from T. obscurus. Phylogenic relationship of T. obscurus CYP1A was also compared to other fish species. The tissue distribution and time-dependant induction of CYP1A mRNA were studied by real-time PCR in T. obscurus exposed to an aryl hydrocarbon receptor (Ahr) agonist, β-naphthoflavone (BNF). The greatest basal expression in livers of control as well as BNF-treated individuals. However, brain, gill, gonad, intestine, and kidney also expressed CYP1A. Muscles expressed the least CYP1A. The results of the time-course study revealed induction in brain and gills after 6 h and at 12 h in most tissues. Except for gills, all other organs retained induced expression of CYP1A mRNA up to 96 h.     

黄河三角洲关键种泥螺Bullacta exarata对沉积物-水体界面溶解氧和营养盐通量的影响

泥螺自2001因养殖目的引入黄河三角洲以来,随着分布范围的扩大和种群数量的增长,已成为当地潮间带的关键种。泥螺给当地民众带来较高收入,但其对底栖生态系统的潜在影响还不清楚。为了明确该种群的生物扰动对底栖微藻和微生物的初级生产,以及对水体-沉积物界面营养盐交换的影响,开展了该项实验。结果表明,在光照条件下,泥螺能显著影响沉积物-水体界面的溶解氧DO通量;在黑暗及无生物处理组的恢复期,泥螺能显著增加两界面间氨氮的通量。底栖微藻和小型生物在黑暗条件下也能增加氨氮的通量;但在有光照条件下,上述微藻和小型底栖动物对沉积物-水体界面间溶解氧和氨氮通量的影响不明显。实验结果为更深入理解泥螺对生态系统的影响提供重要理论支持。     

Assessment of a field incubation method estimating primary productivity in rockpool communities

An open incubation method has been used in many studies to directly estimate primary productivity and ecosystem functioning by measuring photosynthetic and respiratory rates in intertidal rockpool communities. The method measures changes in dissolved oxygen concentrations recorded in situ during an artificial dark period (respiration) and a natural light period (net primary productivity). Although this method has yielded interesting results, its advantages and limitations have yet to be thoroughly tested. The accuracy of the method was investigated in a controlled laboratory environment and compared with field incubations. Atmospheric oxygen diffusion across the air–water interface did not affect incubation measurements under low wind speed (<2 m s⁻¹). Temperature increases during incubations were not greater than in natural rockpools and did not affect primary productivity. The major problem was the oxygen supersaturation which inhibited photosynthesis, thus leading to an underestimation of primary production. To allow comparable measurements, net primary productivity needs to be recorded during the linear phase of the photosynthetic process (<30 min of light) before water reaches supersaturation (<160%). This method gives rapid and reliable estimates of primary productivity thereby allowing biodiversity and ecosystem functioning relationships to be tested using rockpools as natural mesocosms.     

三角帆蚌(Hyriopsis cumingii)珍珠形成初期钙代谢的特征分析

采用生理生化及分子生物学方法,对刚植片的三角帆蚌进行了为期57天的研究,探讨三角帆蚌珍珠形成初期钙的代谢特征。实验每周取样一次,分别测定了珍珠囊和珍珠的直径,珍珠囊和珍珠的重量及水温,外套膜、鳃、围心腔三种组织的钙含量,酸、碱性磷酸酶的比活力,以及外套膜中钙调素基因的表达量。结果表明,植片后三角帆蚌的珍珠囊及珍珠在第22天和43天各出现一个快速生长期。其外套膜和鳃中的酸性磷酸酶比活力第8天升到最高,随后逐渐下降;外套膜中的碱性磷酸酶比活力第15天达到最高,第29天后开始快速下降;鳃和围心腔中的碱性磷酸酶比活力第15天后才开始上升,第29天达到最高。三种组织的钙含量总体呈现上升趋势,其中鳃的钙含量最高并在第43天达到最高值。植片后三角帆蚌外套膜中的钙调素RNA表达量明显增强,第8天和43天的表达量尤其显著。三角帆蚌珍珠的形成主要依赖于鳃和外套膜对钙的代谢,在此过程中酸、碱性磷酸酶以及钙调素起着重要的作用。可能依照钙调素基因上调表达、酸性和碱性磷酸酶激活、鳃和外套膜钙含量升高、珍珠生长的顺序来进行,植片后的第8天、15天和43天是珍珠形成的关键期。     

大西洋牙鲆幼鱼标准代谢的初步研究

测定了大西洋牙鲆幼鱼在禁食和静息状态下的呼吸耗氧率、氨氮排泄率和CO2排出率;研究了它们的呼吸商、氧氮比、能量代谢的特征和能源的化学本质。结果表明,大西洋牙鲆在水温10.8～21.5℃时,其耗氧率Q10=2.336,代谢率的体重系数b=0.832。白天能量代谢率为2.00J/(h·g),夜间能量代谢率为1.474J/(h·g),白天是夜间的1.357倍,最高值出现在09:00(上午),代谢率为2.525J/(h·g),最低值在03:00(夜间),代谢率为1.147J/(h·g)。在水温4～26℃时大西洋牙鲆平均呼吸耗氧率为0.123mg/(h·g);氨氮排泄率2.654μg/(h·g);CO2排出率0.135mg/(h·g);代谢率1.773J/(h·g);O∶N=38.8;呼吸商为0.791。大西洋牙鲆以蛋白质、脂肪和糖类3种营养物质的混合物为能源,随着温度的升高和个体的生长O∶N比值增加,即代谢底物中蛋白质用于氧化供能的比例相对减少,用于生长的比例增加。     

基于能值分析的2006年广东省社会代谢研究

社会代谢分析为全球环境变化人文因素计划的重要课题之一,已成为当前区域生态研究的热点。本文应用H.T.Odum创立的基于生物物理原理的能值方法结合社会代谢概念,对广东省2006年资源利用种类、效率与代谢循环状况进行了分析,通过一系列能值指标,评价广东省社会代谢的可持续性。结果表明：2006年广东省总体呈现较好的发展局面,能值剩余57.31×1022 sej体现了其财富的真正增长,人均能值使用量为1.60×1016 sej,能值福利水平较高;但同时也暴露出影响广东省社会代谢正常运作的原因：输入能值占总能值使用量比为0.73,对进口资源过度依赖;废弃物能值占总能值使用量比为0.26,废弃物产出过多;环境负荷率为14.36,资源的过度使用使环境承受的压力较大等。研究还发现,广东能值可持续性指数呈现逐步下降趋势。广东省目前的代谢过程仍是线性运作模式为主。未来广东省应向循环代谢模式发展,重组并优化其代谢能力,通过建立低消耗高效益产业体系,加大开发替代性资源和新能源,提高废弃物处理能力和完善代谢机制等措施,提高经济社会发展与自然生态环境的和谐程度。