东南亚渔业发展中心的角毛藻生产

鲜藻类饵料在传统上一直是对虾幼体培养中所需要的营养源。在对虾育苗场广泛使用的藻类品种有:骨条藻(Skeletonema costatum)、角毛藻(Chaetoceros calcitrans)和扁藻(Tetraselmis sp.)。而角毛藻是斑节对虾(Penaeus monodon)使用最早的鲜活饵料。从1986～1988年,东南亚渔业发展中心(SEAFDEC)藻类实验室生产的6个品种中,角毛藻占总生产量的34％。同其他5种藻类相比较,角毛藻饵料对斑节对虾的生长和存活率是最高的。     

藻类池进行真鲷育苗获得成功

山东省文登市小观镇海珍品育苗场与山东省水产研究所共同研究利用藻类池进行真鲷鱼育苗试验获得成功,为我国全面开发和多层次综合利用藻类池及对虾育苗池进行海水鱼育苗走出了一条新路。     

螺旋藻在对虾育苗中的应用

在对虾育苗中,幼体饵料的选择对幼体的发育和提高成活率是至关重要的。 溞状Ⅰ期—Ⅲ期,幼体以食植物性饵料为主,有的地方,以扁藻和三角褐指藻等单细胞藻类为主;另一些地方,则选用豆浆或豆浆加蛋黄的人工代用饵料。豆浆的营养价值虽比较高,但不及单胞藻类,它易污染水质,不具有单胞藻类所含的活性物质,且影响对虾幼体的发育。     

养殖对虾微型生物污着症的特征

于1991年3 - 9月和1992年3 - 9月，在中国沿海广东、海南、福建、浙江、江苏、山东、河北、天津和辽宁等9个省市的养殖场采集中国对虾、斑节对虾和长毛对虾3种对虾标本，运用显微和亚显微观察方法，对养殖对虾的微型生物污着症进行研究。结果表明，患该症的对虾其体表污着生物群落通常由微型生物组成，包括各种细菌、藻类和原生动物，主要类群是具柄的缘毛美纤毛虫；其他观察到的常见类群包括丝状和非丝状的细菌、附着性藻类和吸管虫类；在养成期偶尔发现有营薛虫和藤壶等大型污着生物。对育苗期和养成期中国对虾体表的扫描电镜观察发现：在某些对虾体表，污着群落具有明显的分层现象。对虾体表的不同污着程度与其体表污着群落的不同发育阶段有关。据此，认为对虾体表微型生物污着症可能是一种慢性的疾病综合症。     

65Zn在人工海洋小生境中的行为

本文研究了人工小生境中65Zn在悬浮物、底质、藻类、罗非鱼、对虾、毛蚶和文蛤的浓集、排泄作用及它在上述生物体内各组织器官的分布和几种生化物质的含量。结果表明,悬浮物对65Zn具有高的浓集能力;藻类对65Zn的浓集两天后达到动态平衡;罗非鱼,对虾和毛蚶的肠道及毛蚶的鳃等部位,65Zn的浓集系数很高,但排泄也很快,是65Zn在这些生物体中代谢的紧要器官;核酸系统65Zn的含量最高,且RNA>DNA,有机酸系统含量最少。     

利用稳定同位素(15N)示踪技术研究浮游藻类氮素吸收速率特征

浮游藻类对溶解态氮的吸收同化是湖泊氮生物循环和水体富营养化发生机制探讨的关键环节。本文通过~(15)N稳定同位素添加实验以铜绿微囊藻(Microcystis aeruginosa)、海链藻(Thalassiosira sp.)、卡德藻(Tetraselmis sp.)、剧毒卡尔藻(Karlodinium veneficum)以及盐水隐藻(Rhodomonas salina)为研究对象,从浮游藻类氮素吸收时间、营养盐基质以及藻种差异三个方面研究五种藻类对铵氮(NH_4~+-N)、硝氮(NO_3~--N)、尿素氮(Urea-N)三种形态氮的吸收特征。研究发现:(1)浮游藻类对三种形态氮的吸收均在1h时吸收速率最高,其氮素吸收过程为快速吸收。(2)浮游藻类优先吸收还原态氮,其中NH_4~+-N吸收速率最高,当培养周期为1d和4d时浮游藻类对NH_4~+-N吸收速率的均值分别为4.05和4.15μmol/(L·h);浮游藻类对Urea-N吸收相对偏好系数为25.18—713.42,表现出对小分子溶解态有机氮的特定偏好性。(3)不同藻种对氮素吸收具有不同特征,其中,剧毒卡尔藻对三种形态氮的吸收速率均为最高,而铜绿微囊藻的吸收速率均为最低;不同藻种不同培养时间氮素吸收速率差异与浮游藻类生长周期等特性有关。不同浮游藻类对不同形态氮素表现出吸收特异性,对水体氮负荷和浮游藻类水华优势种形成将产生重要影响。     

斑节对虾节水型养殖期间虾池硫化物含量的变化特征

在斑节对虾节水型养殖期间,观测了虾池底质和海水中硫化物含量的变化.结果表明,投放有益微生物的试验池与未投放有益微生物的对照池相比,底质硫化物含量波动较小,增高的速度较慢、增幅较小.在养殖后期试验池底质硫化物含量只增高了 68%,而对照池的增高了 252%.养殖过程中海水硫化物浓度呈阶段式和波浪式增高,在试验池中其浓度多数时间比对照池中的低.有益微生物能在一定程度上抑制水体和底质中硫化物的积累,但对老化虾池效果较差.由于节水型养殖模式利用有益微生物分解养殖过程中产生的有机物,采用单细胞藻类吸收利用营养盐,使养殖环境质量得到改善.     

海水增养殖品种结构布局的探讨

本文在分析我国海水增养殖生产发展过程与现状的基础上,较为详细地研究探讨了我国海水增养殖生产进一步发展所要求的良好品种结构布局。首先深入调查分析了我国“七五”末期生产发展资金、苗种、饲料可供量和产品市场容量,生态环境、技术进步、保证低收入经济增长要求等制约因素后,运用线性规划模型运算,得到1990年海水养殖品种结构布局格局:渤海区以对虾生产为主,鱼类、滩涂贝类和贻贝配套生产为辅;北黄海区以海带、贻贝、扇贝等海珍品,对虾生产为主,滩涂贝类、鱼类生产为辅;南黄海区以文蛤、对虾、紫菜生产为主,其它品种生产为辅;东海区以对虾、贝类生产为主,鱼类、藻类和其它品种生产为辅;南海区以对虾、贝类生产为主,鱼类、藻类生产为辅。整个海水养殖生产将形成以虾(鱼)带贝、以贝保藻、以藻养珍,藻、贝、鱼虾海珍品类比例为0.20:0.60:0.20的格局。海水增殖的重点是建立三个中心开发区:渤海增殖中心开发区、东黄海主要港湾增殖和滩涂经济贝类增殖中心开发区和南海增殖中心开发区。放流品种以对虾、海蜇、岩礁鱼类、滩涂和浅海贝类为主。     

对虾三重框刺网提高了捕捞效果

为恢复和保护渤海渔业资源,对虾流刺网已成为渤海渔场捕捞对虾的主要渔具。为进一步提高对虾流刺网的捕捞效率,1993年天津市水产研究所开展了虾三重框刺网的试验研究,并取得了较好效果。 对虾三重框刺网(下称试验网)是在对虾三重流刺网(下称对比网)的基础上改革研制而成的。其主尺度为56米×1.6米,内网衣以     

使用干藻饲养对虾幼体

传统上,鲜活藻饵料是对虾幼体的营养源,但是其培养劳动强度大、技术复杂。寻求适合的非活性藻类代用鲜活藻饵料,是当今养殖业急需解决的问题之一。许多研究者发现,利用冷冻和晒干的角毛藻(Chaetoceroscal citrans)、扁藻(Tetrasehnis chuii)和等鞭金藻(Lschrysis)作斑节对虾(penaeus menodon)幼体的饵料,其干品比冷冻品好。本研究就是以喷雾干的扁藻(T.suecica)代替鲜活藻类来培养万氏对虾(P.(?)namei)幼体。     

热锻炼对龙须菜高温胁迫响应的影响

夏季高温是限制龙须菜(Gracilariopsis lemaneiformis)生长和发育的一个主要问题。本研究以野生龙须菜作为材料,经过28℃的热锻炼预处理72 h,再分别置于32、36、40℃高温胁迫24 h,并测定了高温胁迫条件下龙须菜的丙二醛(MDA)、过氧化氢(H2O2)和可溶性蛋白质的含量,以及超氧化物歧化酶(SOD)活性和抗坏血酸(AsA)水平等生理指标,研究了龙须菜对高温胁迫的响应。结果表明:热锻炼能维持藻体较低的MDA含量,降低H2O2的产生速率,缓解藻体的膜脂过氧化伤害;同时热锻炼缓解了可溶性蛋白质的降解,增加了SOD酶的比活力,缓解了AsA的下降速率,说明热锻炼能缓解高温胁迫对藻体的伤害,有效地提高了龙须菜对高温胁迫响应的能力。     

A new method for continuous measurements of O2 in surface water in combination with pCO2 measurements: Implications for gas phase equilibration

An autonomous system for the recording of the surface water pCO₂ in the Baltic Sea was complemented by a module for continuous O₂ measurements. An optical O₂ sensor was used and in analogy to the determination of the pCO₂, the pO₂ was determined in the headspace of an equilibrator. By this procedure the automatic periodic calibration was considerably facilitated and biofouling was avoided. Uncertainties were associated with the use of a vented equilibrator. Due to the continuous pressure equalization with the ambient atmosphere, the headspace partial pressure of any gas (e.g. pO₂, pCO₂) reflects a steady state that may deviate substantially from the equilibrium. To calculate the true equilibrium pO₂ and thus the O₂ concentration in the water sample, we derived an equation that is based on the measurement of the headspace O₂ mol fraction, x_O2, and on the assumption that the surface water was saturated with atmospheric N₂ and Ar. Model calculations indicated that deviations from this assumption are less then 2% for most of the year. The combined pO₂/pCO₂ measurement system was deployed in July 2005 on a cargo ship that commutes regularly between the southwestern Baltic Sea and the Gulf of Finland. First results showed a reasonable agreement with O₂ data obtained at a measurement platform in the vicinity of the ship's track. The spatial resolution of the O₂ measurements was similar to that of the pCO₂ system and allowed the identification of small scale (< 1 nautical mile) biogeochemical and hydrographical inhomogeneities.     

Tropical seagrass-associated macroalgae distributions and trends relative to water quality

Tropical coastal marine ecosystems including mangroves, seagrass beds and coral reef communities are undergoing intense degradation in response to natural and human disturbances, therefore, understanding the causes and mechanisms present challenges for scientist and managers. In order to protect our marine resources, determining the effects of nutrient loads on these coastal systems has become a key management goal. Data from monitoring programs were used to detect trends of macroalgae abundances and develop correlations with nutrient availability, as well as forecast potential responses of the communities monitored. Using eight years of data (1996–2003) from complementary but independent monitoring programs in seagrass beds and water quality of the Florida Keys National Marine Sanctuary (FKNMS), we: (1) described the distribution and abundance of macroalgae groups; (2) analyzed the status and spatiotemporal trends of macroalgae groups; and (3) explored the connection between water quality and the macroalgae distribution in the FKNMS. In the seagrass beds of the FKNMS calcareous green algae were the dominant macroalgae group followed by the red group; brown and calcareous red algae were present but in lower abundance. Spatiotemporal patterns of the macroalgae groups were analyzed with a non-linear regression model of the abundance data. For the period of record, all macroalgae groups increased in abundance (Ab_i) at most sites, with calcareous green algae increasing the most. Calcareous green algae and red algae exhibited seasonal pattern with peak abundances (Φ_i) mainly in summer for calcareous green and mainly in winter for red. Macroalgae Ab_i and long-term trend (m_i) were correlated in a distinctive way with water quality parameters. Both the Ab_i and m_i of calcareous green algae had positive correlations with NO₃⁻, NO₂⁻, total nitrogen (TN) and total organic carbon (TOC). Red algae Ab_i had a positive correlation with NO₂⁻, TN, total phosphorus and TOC, and the m_i in red algae was positively correlated with N:P. In contrast brown and calcareous red algae Ab_i had negative correlations with N:P. These results suggest that calcareous green algae and red algae are responding mainly to increases in N availability, a process that is happening in inshore sites. A combination of spatially variable factors such as local current patterns, nutrient sources, and habitat characteristics result in a complex array of the macroalgae community in the seagrass beds of the FKNMS.     

Green synthesis of iron oxide (Fe3O4) nanoparticles using two selected brown seaweeds: Characterization and application for lead bioremediation

The exploitation of different plant materials for the biosynthesis of nanoparticles is considered a green technology because it does not involve any harmful chemicals. In this study, iron oxide nanoparticles (Fe₃O₄-NPs) were synthesized using a completely green biosynthetic method by reduction of ferric chloride solution using brown seaweed water extracts. The two seaweeds Padina pavonica (Linnaeus) Thivy and Sargassum acinarium (Linnaeus) Setchell 1933 were used in this study. The algae extract was used as a reductant of FeCl₃ resulting in the phytosynthesis of Fe₃O₄-NPs. The phytogenic Fe₃O₄-NPs were characterized by surface plasmon band observed close to 402 nm and 415 nm; the obtained Fe₃O₄-NPs are in the particle sizes ranged from 10 to 19.5 nm and 21.6 to 27.4 nm for P. pavonica and S. acinarium, respectively. The strong signals of iron were reported in their corresponding EDX spectra. FTIR analyses revealed that sulphated polysaccharides are the main biomolecules in the algae extracts that do dual function of reducing the FeCl₃ and stabilizing the phytogenic Fe₃O₄-NPs. The biosynthesized Fe₃O₄-NPs were entrapped in calcium alginates beads and used in Pb adsorption experiments. The biosynthesized Fe₃O₄-NPs alginate beads via P. pavonica (Linnaeus) Thivy had high capacity for bioremoval of Pb (91%) while that of S. acinarium (Linnaeus) Setchell 1933 had a capacity of (78%) after 75 min. The values of the process parameters for the maximum Pb removal efficiency by Fe₃O₄-NPs alginate beads synthesized via P. pavonica (Linnaeus) Thivy were also estimated.     

油藻混合水体遥感反射比光谱分析

辐射传输模式HydroLight是研究水体辐射传输特性的有效工具,同时也是进行石油类水体辐射传输特性的有效模型。本文基于2018年8月在辽宁大连港海域实测的石油类污染水体的表观及固有光学量数据,通过设置不同浓度的配比模拟试验,利用HydroLight对油类物质和藻类物质的单一组分和两者混合水体的遥感反射比（remote sensing reflectance,R_rs）光谱进行了模拟。模拟结果表明：（1）在仅含油类物质单一组分的水体中,R_rs随着油浓度C_oil的变化分为两个特征波段：400~480 nm和480~700 nm。在400~480 nm波段范围内R_rs随C_oil的增加而减小,在480~700 nm随C_oil的增大而增大;（2）在仅含藻类物质的单一成分水体中,叶绿素的光谱特性需要其浓度C_chl达到一定值才能表现出来,在低C_chl时的R_rs光谱特性反映为纯水的光谱特性;（3）在油藻混合水体中,随C_oil的增加会增大叶绿素的R_rs,但不会明显改变叶绿素的R_rs随波长的变化趋势,这说明油藻混合水体的光谱形状主要受叶绿素的影响,油类物质的存在只改变光谱的量值。利用HydroLight对石油类污染水体的R_rs展开研究,有助于丰富水色遥感基础研究,对完善各类水体生物光学模型研究具有重要的理论意义。     

60Co、137Cs在几种海洋生物中浓集问题的初步研究

本文对核电站的主要废物60Co、137Cs在几种海洋生物中的浓集和若干有关的问题进行了初步研究.     

Diffusive and total oxygen uptake of deep-sea sediments in the eastern South Atlantic Ocean:in situ and laboratory measurements

Total O₂ uptake rates were measured by the benthic flux chamber lander ELINOR, and O₂ microprofiles were measured by the profiling lander PROFILUR in the eastern South Atlantic. Diffusive O₂ fluxes through the diffusive boundary layer and the depth distribution of O₂ consumption rates within the sediment were calculated from the obtained microprofiles. The depth integrated O₂ consumption rate agreed closely with the diffusive O₂ uptake at all stations. Total O₂ uptake was 1.2–4.2 times the diffusive O₂ uptake, and the difference correlated with the abundance of macrofauna in the sediment. Diffusive O₂ uptake and O₂-penetration depths correlated with the organic content of the sediments and exhibited an inverse correlation with water depth. Total and diffusive rates of in situ O₂ uptake were higher than previously published data for shelf and abyssal sediments in the Atlantic, but were comparable to rates from upwelling areas in the eastern Pacific. Laboratory measurements on recovered sediment cores showed lower O₂ penetration depths and higher diffusive uptake rates than in situ measurements. The differences increased with increasing water depth. We primarily ascribe this compression of O₂ profiles to a transiently increased temperature during recovery and enhanced microbial activity in decompressed sediment cores. Total O₂ uptake rates measured in the laboratory on macrofauna-rich stations were, in contrast, lower than those measured in situ because of underrepresentation and disturbance of the macrofauna.     

二十三种有害物质对对虾的急性致毒试验

本文报道了在常温、静水条件下,用通用的鱼类毒性试验方法进行了二十三种有害物质对对虾急性致毒试验,为“渔业水质标准”的制订提供了依据。     

浒苔多糖对羟自由基的清除作用研究

研究确定了Fenten(水杨酸法)反应所需水杨酸、H2O2和Fe2+的浓度,并用水杨酸法对浒苔(Entero-morpha prolifera)水提多糖及其酸提多糖对羟自由基的清除能力进行了测定,同时,与合成抗氧化剂BHT和TBHQ进行对比。结果表明,浒苔水提多糖及酸提多糖对羟自由基均有一定的清除效果,且清除率与浓度存在剂量依赖关系,酸提多糖对羟自由基的清除能力大于水提多糖。在较高质量浓度(1.2 g/L)时酸提多糖对羟自由基的清除能力是水提多糖的2倍。