大型海藻的营养盐代谢及其与近岸海域富营养化的关系

大型海藻是近岸海域重要的初级生产者,近年来人们愈来愈认识到大型海藻在近岸海域富营养化生物修复中的重要性,同时,富营养化也可能招致某些机会主义大型海藻种类的爆发生长,因此,进一步理解大型海藻与营养盐供应变化的关系就显得非常重要。本文从大型海藻营养盐代谢与海水中营养盐供应变化(主要是富营养化)的生理生态关系角度对相关问题进行评述,主要包括影响大型海藻营养盐吸收特性的重要因素、海水中营养盐的供应及大型海藻对营养盐的细胞贮存、大型海藻对营养盐的生态需求、大型海藻对近岸海域富营养化的生态响应等问题。文章还对今后的研究提出了展望。     

温度与盐度对吉富品系尼罗罗非鱼幼鱼生长和肝脏抗氧化酶活力的协同影响

采用中心复合试验设计(CCD)和响应曲面方法(response surface methodology, RSM),探讨了温度(16～37 ℃)和盐度(0～18)对吉富罗非鱼幼鱼生长和肝脏抗氧化酶活力的协同影响.结果表明： 温度和盐度的一次与二次效应对吉富罗非鱼幼鱼特定生长率（SGR）有显著影响(P<0.05),随着温度或盐度的上升,其特定生长率呈先升后降的变化.温度与盐度间存在互作效应(P<0.05),温度为16～20 ℃时,幼鱼的特定生长率在盐度为9～10时较高;在温度27～32 ℃、盐度3～5时较高;高温环境下（35～37 ℃）,淡水环境中的幼鱼生长较快.温度和盐度分别为28～30 ℃和6～8时,超氧化物歧化酶（SOD）和过氧化氢酶（CAT）的活力较高,温度的一次效应与盐度的二次效应对两种酶活力均有显著影响(P<0.05),温度与盐度对CAT活力有互作效应,高温与高盐环境会抑制SOD和CAT活力的表达.SGR、SOD和CAT因子与响应值间二次多项回归方程的决定系数分别达到0.954、0.831和0.942(P<0.05),可用于预测;温度效应对吉富罗非鱼幼鱼生长和抗氧化酶活力的影响较盐度明显.在罗非鱼的养殖过程中应合理安排养殖环境,降低氧化胁迫,以促进罗非鱼的生长与抗病力的提高.     

海水盐度、温度对文蛤稚贝生长及存活的影响

在实验室条件下,研究了不同盐度（19个梯度）、温度（17个梯度）对文蛤稚贝生长和存活的影响.结果表明：文蛤稚贝的适宜生存盐度在6.5～39.5,最适生存盐度在9.0～31.0,适宜生长盐度在7.3～38.7,最适生长盐度在15.0～23.0;其适宜生存温度在4.0 ℃～36.1 ℃,适宜生长温度在7.0 ℃～35.4 ℃,较适宜生长温度在17 ℃～33.5 ℃,最适生长温度在24 ℃～27 ℃.文蛤稚贝对高温度、低盐度有较强的适应性.     

温度和盐度对浒苔生长和光合生理特性的影响

为研究海水盐度和温度对大型海藻光合生理影响的复合效应,选取浒苔（Ulva prolifera）为实验材料,探讨不同温度（22℃和15℃）和不同盐度（25和10）对浒苔的相对生长速率、色素含量、叶绿素荧光参数、超氧化物歧化酶（SOD）活性、可溶性蛋白含量等影响。结果表明:在低温条件下,盐度对浒苔生长的影响不显著,而在正常温度条件下,盐度降低显著降低了浒苔的生长;在低盐条件下,尽管差异不显著,温度降低呈现出促进浒苔生长的趋势,但在正常盐度条件下,低温降低了浒苔的生长。相对于温度变化,盐度变化对浒苔潜在的光合效率（F_v/F_m）影响不明显,但低温低盐处理下浒苔具有较高的效光化学效率（F_v’/F_m’）、光能利用效率（α）、非光化学淬灭（NPQ）、SOD酶活性及可溶性蛋白含量。     

温度、光照和盐度对2株曼氏骨条藻生长及脂肪酸组成的影响

研究温度、光照、盐度对2株曼氏骨条藻（Skeletonema munzelii）SM-1、SM-2生长、总脂含量及脂肪酸组成的影响,以确定其生长及油脂、多不饱和脂肪酸积累的最适生态条件。在实验室智能光照培养箱内不充气培养控制条件下,采用单因子试验分别研究了不同温度（10、15、20、25和30℃）、光照强度（20、40、60、80、100和120μmol/m2·s）、盐度（10、15、20、25、30、35和40）对2株藻的生长、总脂含量及脂肪酸组成的影响。结果表明：不同温度、光照强度及盐度对2株藻的生长、总脂及脂肪酸含量影响均有显著影响（P〈0.05）。藻株SM-1生长的最适温度为25℃,最适光强60μmol/m2·s,最适盐度30,而低温（10~15℃）,低光照（20μmol/m2·s）,低盐度（盐度15）更有利于总脂及PUFA的积累。SM-2生长的最适温度为20℃,最适光强60μmol/m2·s,最适盐度30,而低温（10~15℃）,低光照（20μmol/m2·s）更有利于其总脂及PUFA的积累,低盐（盐度15）则更有利于PUFA的积累。因此在实际生产中,2株藻可先在最适条件下培养以增加生物量,后转至利于PUFA积累的条件下提高PUFA产量。     

大型海藻对主要营养盐的吸收的研究进展

针对当前海洋环境面临的严重的富营养化现状,利用大型海藻的吸收氮磷的能力可以有效治理和修复海洋的富营养化,实现海洋污染的生态修复.本文介绍了大型海藻主要营养盐物质(C、N、P)的吸收的其影响因素主要有物理因素、化学因素和生物因素等,大型海藻吸收营养盐的现状,研究方法,前景展望等.     

香港及珠江口海域有害赤潮发生机制初步探讨

回顾了香港及珠江口海域赤潮发生和藻毒素污染的历史及研究状况,结合3种代表赤潮藻种最适光温盐生长实验,4种不同形态氮营养盐对几种常见赤潮藻种生长影响实验,以及不同营养盐,温度,盐度条件下赤潮藻群落变化过程实验,初步探讨了物理,化学,生物等环境因子在香港和珠江口海域赤潮发生中的作用机制。     

舟山附近海域富营养化的时空分布及其与环境因子的关系

根据2008年春季(5月)和夏季(8月)在舟山附近海域调查监测资料,采用改良后的营养指数法,结合N/P(物质的量比)潜在性富营养化法,对该海域在春季和夏季的富营养化水平进行了评价,并分析了该海域富营养化的时空分布特征,对富营养化指数与环境因子的相关关系进行了讨论,同时对两种方法的结果进行了比较分析.营养指数法计算结果显示:舟山附近海域的富营养化程度较低,各调查站位富营养化指数均小于富营养化阀值;春季的富营养化水平高于夏季;春季、夏季富营养化指数的平面分布均表现出沿岸到离岸方向呈逐渐降低的特点;春季调查海域N/P平均值为17.35,略高于Redfield系数,夏季N/P平均值为56.34,具有明显的营养盐比例不平衡的特征.潜在性富营养化法计算结果显示:春季属于富营养水平,夏季属于磷限制潜在性富营养;富营养化指数与盐度、溶解氧、pH相关性均不显著,调查海域富营养化水平的时空变化主要受地表径流冲谈水、浮游植物、外海海流等的共同影响.     

温湿度对番茄刺皮瘿螨实验种群的影响

在同一湿度（53%RH）不同温度（14℃、17℃、20℃、23℃、26℃、29℃、32℃、35℃及同一温度（26℃）不同湿度（30%RH、53%RH、75.5%RH、85%RH、92.5%RH、100%RH）组合条件下,测定了温湿度对番茄刺皮瘿螨Aculops lycopersici (Massee)生长发育及繁殖的影响。结果表明,温、湿度对该螨存活率有明显影响,以23℃（53%RH）和75.5%RH（26℃）条件下最高,分别为89.9%和87.1%; 其发育历期较短,在14～35℃和30%～100%RH范围内,历期随温度升高而缩短,随湿度升高而延长; 番茄刺皮瘿螨的发育起点温度较高,卵、若螨和整个世代的发育起点温度分别为10.51、9.02和9.15℃。完成一代需要105.56日·度。温湿度对番茄刺皮瘿螨的繁殖力有明显影响,产卵期随温度升高而缩短,随湿度升高而延长; 产卵量在26℃(53%RH)和53%RH(26℃)下最高,每头雌虫产卵分别为44.3粒和42.2粒; 26℃(53%RH)和53%RH(26℃)条件下种群的内禀增长率最高,分别为0.2645和0.2669。结果表明,适宜的温湿度条件为温度26～29℃、相对湿度53%～75%。     

温度、盐度对海月水母碟状体生长及存活的影响

海月水母为我国近海主要大型灾害水母种类之一,当自然环境适宜其生长与繁殖时,易出现暴发性的增殖现象,严重破坏了我国近岸海洋生态系统的稳点与平衡。采用实验生态学方法,研究了温度(2.5、5、7.5、10、15、20、25、27.5、30℃)和盐度(15、20、25、30、35、40)对海月水母碟状体存活与生长的影响,实验共进行30d。结果显示,在实验设置的温盐范围内,温度、盐度均显著影响碟状体的存活与生长。在盐度15-35条件下,海月水母碟状体可以在温度2.5-25℃存活,在15-25℃范围内可正常生长;在温度20-25℃和盐度20-30条件下适宜海月水母碟状体生长,其中温度20℃和盐度25条件下海月水母碟状体特定生长率达到最大。与盐度相比,温度对碟状体的影响较大,在盐度15-35条件下,随着温度的升高,碟状体的伞径逐渐增大,其碟状体形态向水母体形态的转变速度加快。在达到临界点25℃时,若继续升高温度,碟状体的生存率与生长率显著下降。温度与盐度对海月水母碟状体的生存与生长具有明显的交互效应,碟状体在实验过程中表现出在较低温度条件下提高了对较高盐度的适应性。研究表明,温度、盐度的变化显著影响碟状体的生长与存活,直接导致碟状体种群数量变动,进而影响成熟水母体种群数量。结论为进一步探索大型水母暴发的生态环境机理提供重要科学依据。     

Growth of a dissociated, filamentous stage of Codium species in laboratory culture

Unialgal cultures were established from isolated utricles for all five Codium species occurring in the British Isles and growth studies performed under different conditions of temperature (10-30 °C), photon irradiance (0-175 μmol m-2 s-1) and salinity (0-100% seawater growth medium). The species studied were C. fragile ssp. tomentosoides, C. fragile ssp. atlanticum, C. adhaerens, C. bursa, C. tomentosum and C. vermilara. All cultures developed into growth forms comprised of branched, dissociated, coenocytic filaments. All grew rapidly in culture, although the conditions for optimum growth sometimes differed for the individual entities. The development of typical Codium plants, with utricles, similar to the parental material, occurred only occasionally. The rapid growth of the dissociated, filamentous forms in laboratory culture led to the provision of sufficient quantities of plant material to enable detailed studies to be made of the lectins present in several of the species. This revised version was published online in August 2006 with corrections to the Cover Date.     

管藻目绿藻叶绿素蛋白复合物特性及比较研究

By mild PAGE method, 11, 11, 7 and 9 chlorophyll-protein complexes were isolated from two species of siphonous green algae (Codium fragile (Sur.) Hariot and Bryopsis corticulans Setch.), green alga (Ulothrix flacca (Dillw.) Thur.), and spinach (Spinacia oleracea Mill.), respectively. Apparent molecular weights, Chl a/b ratios, distribution of chlorophyll, absorption spectra, low temperature fluorescence spectra of these complexes were determined, and compared with one another. PSⅠ complexes of two siphonous green algae are larger in apparent molecular weight because of the attachment of relative highly aggregated LHCⅠ. Four isolated light-harvesting complexes of PSⅡ are all siphonaxanthin-Chl a/b-protein complexes, and they are not monomers and oligomers like those in higher plants. Especially, the absence of 730 nm fluorescence in PSⅠ complexes indicates a distinct structure and energy transfer pattern.     

OCCURRENCE OF CODIUM FRAGILE SUBSP. TOMENTOSOIDES (CHLOROPHYTA: BRYOPSIDALES) IN MARINE EMBAYMENTS OF SOUTHEASTERN AUSTRALIA

Codium fragile (Sur.) Hariot subsp. tomentosoides (van Goor) Silva, a widespread weedy species, is reported from Australia for the first time. Specimens were initially found in June 1996 in Corner Inlet, Victoria, where the species fouled fishing nets. This invasive chlorophycean alga was subsequently found in large numbers on 30 January 1997 in Port Phillip Bay and on 9 March 1998 in Western Port, Victoria. Presumably the species is native to Japan. The alga formed dense stands on rocky substrata in intertidal or in subtidal regions. In Port Phillip Bay, the species was also found attached to the common blue mussel Mytilus edulis planulatus Lamarck, and in Western Port it was found attached to the mud oyster Ostrea angasi Sowerby. Results of this study suggest that recruitment of juvenile germlings and growth of C. fragile subsp. tomentosoides differs between populations in Port Phillip Bay and those in Western Port.     

温度、盐度、光照对海洋卡盾藻生长和产毒的影响

在正交试验条件下,分析了盐度、温度、光照强度对海洋卡盾藻生长和产毒的影响.结果表明：在盐度22、33、45和温度20 ℃、25 ℃、30 ℃以及光照强度2000、3000、4500 lx条件下,三因素对海洋卡盾藻生长的影响均不显著,盐度是影响海洋卡盾藻产毒的主要因子;盐度45、温度30 ℃、光照2000 lx下海洋卡盾藻的比生长速率最大,盐度22、温度20 ℃、光照4500 lx下海洋卡盾藻的产毒能力最强;低盐条件不利于海洋卡盾藻的生长,但有利于溶血毒素的合成;当海洋卡盾藻生长受到限制时,其溶血毒素合成增多.     

SEXUAL REPRODUCTIO IN CODIUM FRAGILE SSP. TOMENTOSOIDES (CHLOROPHYCEAE) FROM THE NORTHEAST COAST OF NORTH AMERICA1

Male and female gametes were formed within the same gametangiurn on reproductive plants of Codium fragile (Sur.) Hariot ssp. tomentosoides (Van Goor) Silva growing off Appledore Island in the Gulf of Maine, USA. The female gametes were approximately twice the diameter of male gametes and outnumbered male gametes in the same gametangium by approximately six times. Fusion appears to require gametes from different gametangia if not different plants.     

持续高温胁迫对克氏原螯虾生长、消化酶活性与免疫指标的影响

为探讨持续高温胁迫对克氏原螯虾(Procambarus clarkii)生长及健康的影响,分别在适宜温度(24℃,对照)和不同高温胁迫温度(29℃、32℃和35℃)条件下对该虾[体重(7.19±0.29)g]进行了为期30d的养殖试验.结果显示:(1)随着胁迫温度的升高克氏原螯虾的成活率(SR)显著下降(P<0.05)...     

温、光、盐对硅藻STR01生长、总脂、脂肪酸的影响

为了优化新分离STR01的生态培养条件, 采用单因子试验和正交试验研究了不同温度、光照强度、盐度和温、光、盐三因素三水平对该藻的生长、总脂和脂肪酸组成影响。结果表明: 温、光、盐对STR01的生长、总脂和脂肪酸组成影响显著(P<0.05)。生长的适宜温度为15—35℃, 最适25—30℃(K值达0.679—0.682), 总脂含量积累的最适温度是25℃(总脂可达17.23%), 温度20℃时有利于该藻PUFA的积累, 可达34.23%。STR01生长的适宜光照强度为40—120 μmol/(m2·s), 最适光强为60 μmol/(m2·s), 光照强度40 μmol/(m2·s)有利于该藻的PUFA积累, 可达34.29%。STR01生长的适宜盐度为10—35, 最适盐度25, 盐度25时PUFA含量较高(43.42%)。正交试验结果表明温度对STR01的平均相对生长速率和总脂含量影响显著, 生长的最优组合: 温度30℃、光照强度60 μmol/(m2·s)、盐度25, 该组合下的生长速率达0.756; 总脂含量积累的最优组合: 温度30℃、光照强度60 μmol/(m2·s)、盐度20, 该组合下的总脂含量为20.00%。PUFA的最优组合: 温度25℃、光照强度60 μmol/(m2·s)、盐度20, 该组合下PUFA的含量为35.37%。综上所述: 该藻生长迅速, 总脂含量较高, PUFA丰富, 是一种可开发利用的耐高温浮游硅藻。     

96 Recognizing cryptic species: investigations into the molecular relatedness and morphological diversity of the species of the red algal genus plocamium (plocamiales, florideophyceae)

Specimens of Codium fragile (Suringar) Hariot ssp. tomentosoides were collected from 9 sites in New England, and Long Island, New York at intervals throughout the years 1999-2003. Segments were removed from the thalli and chopped into fine fragments, mostly individual utricles and medullary filaments. Fragments were incubated in enriched seawater in dim light at 15C, 12:12 LD. Within 2–3 days, in almost all cases (more than 300) motile cells formed in many of the utricles and filaments. These were 10–15 micrometer elongated biflagellate heterokont cells. They appeared to consume the chloroplasts, and within 24 hours were reduced to colorless cells, about 5 micrometers long. These cells are unable to grow in Codium chloroplast suspensions. They appear to be always associated with Codium thalli, despite attempts to clean the thalli, and were never seen in utricles or filaments of intact plants. Their ultrastructure is under investigation and will be reported on here.     

温度、光照、盐度及pH对旋链角毛藻生长的影响

以旋链角毛藻(Chaetoceros curvisetus)为实验材料,采用f/2培养基,设置了2个盐度梯度(25和30),4个温度梯度(15℃、20℃、25℃和30℃),3个光照梯度(29.3μE·m^-2·s^-1、78.12μE·m^-2·s^-1和126.95μE·m^-2·s^-1),3个pH梯度(7.0、7.5和8.3)的处理,并计算了不同培养条件下藻细胞在指数生长期的比生长率,比较研究了温度、光照、盐度及pH等环境因子对旋链角毛藻生长的影响。进一步进行盐度、光照的两因素正交实验,并检验两者的交互作用。其中盐度设25、30两个水平,光照强度设29.3μE·m^-2·s^-1、78.12μE·m^-2·s^-1和126.95μE·m^-2·s^-1三个水平。实验结果表明,温度为20℃,光照为78.12μE·m^-2·s^-1,盐度为25,pH在8.3时是旋链角毛藻的最佳生长条件,此时最大比生长率和生物量达到最高,温度对藻类生长的影响比盐度,光照,pH的要明显得多,实验中其他处理均会抑制其生长。     

EFFECTS OF TEMPERATURE,SALINITY, IRRADIANCE AND DIURNAL PERIODICITY ON GROWTH AND PHOTOSYNTHESIS IN THE DIATOM NITZSCHIA AMERICANA; LIGHT-SATURATED GROWTH1

The physiological response of an estuarine clone of Nitzschia americana Fryx3ell was measured under experimental conditions of temperature and salinity which represent the average range of these variables in the Cape Fear River Estuary, North Carolina. The influence of temperature (10, 15, 20, 25, 30°C) and salinity (8, 15, 20, 26, 32‰) on specific growth rates, μ, and parameters of photosynthesis-irradiance curves, α, and P_max were measured during maximum and minimum rates of diurnal photosynthesis using axenic semi-continuous batch cultures maintained at an irradiance saturating for photosynthesis (140 μE m^-2·s-1). There was an increase in μ with increasing temperature up to a broad uptimum (25 ± 2.5°C), above which μ gradually declined. At the predicted optimum temperature of 25°C, μ increased as a linear function of salinity. oth light-limited (α) amd light-saturated (P^max) rates of photosynthesis increased as salinity decreased. The effect of temperature on a and P^max was complex and dependent on salinity. P^max exhibited a diurnal periodicity, whereas estimates of a were not significantly different between sampling periods. Growth efficiencey opf N. americana, calculated as the ratio between specific growth rates and rates of gross photosynthesis, increased with an increase in salinity with a maximum at the predicted optimum temperature and salinity of 25°C and 32‰, suggesting and uncoupling between photosynthesis and growth at nonoptimum growth conditions.