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1.
硒碲胁迫对两种螺旋藻生长的影响   总被引:8,自引:3,他引:8  
研究了硒(Na2SeO 3)和碲(Na2TeO 3)胁迫对钝顶螺旋藻(Spirulinaplatensis)和极大螺旋藻(Spirulinamaximum)生长的影响。结果表明 ,两种藻对硒、碲表现出不同的耐性。对于S.platensis,CSe≤200mg/L促进生长 ,CTe<100mg/L影响不大 ,CTe≥100mg/L抑制生长 ,CSe≥800mg/L或CTe=400mg/L藻死亡 ;而对于S.maximum ,CSe=25mg/L时促进生长 ,CTe≤25mg/L无影响 ,CTe≥50mg/L明显抑制生长 ,CSe≥800mg/L或CTe≥600mg/L则死亡。而在培养周期内分次添加硒、碲 ,当累计达到CSe(CTe)=800mg/L,两种藻仍能正常生长。表明硒、碲添加方式不同 ,产生明显不同的效应。  相似文献   

2.
本文提出不同比重海水对海带游孢子的放散、附着,胚孢子的萌发,配子体的生长发育和幼孢子体生长的影响 实验结果表明:(1)海带配子体的生长发育对比重的适应能力较强,在高比重和低比重的海水中虽然死亡率很高、生长发育缓慢,但总有一部分个体能生活下来。配子体对比重的适应范围是1.01010-1.03510;(2)海带的幼孢子体对比重的适应能力较小。其适应范围是1.02000-1.03510.尤其是低比重海水能引起泡烂。本实验结果对指导海带苗种生产有一定意义。  相似文献   

3.
我国是大型海藻养殖大国 ,在海洋生物学的许多方面研究居世界前列 ,但是有关病害方面的基础研究还比较薄弱。海藻养殖过程中也会发生各种各样的病害 ,给生产造成损失。有的育苗场因病害连年亏损 ;有的育苗场时好时坏 ,至今原因不明。因此 ,为了避免象对虾和扇贝养殖过程中由于病害而造成的大规模死亡 ,进行大型经济海藻病害发生及其抗病防御体系的研究 ,重视海藻养殖业的健康可持续发展是非常必要的。本文综述了大型经济海藻养殖过程中的主要病害、研究现状及其展望。1海带养殖过程的主要病害胡敦清、房历生、丛沂滋等人的研究表明 ,人工培…  相似文献   

4.
孤雌生殖海带对氯霉素和潮霉素的敏感性研究   总被引:6,自引:2,他引:6  
于1997年1-4月,以本所培养的孤雌生殖海带为材料,运用统计不傣对氯霉素、潮纱的敏感性,以期得出氯霉素、潮霉素对不同长度孤雌生殖海带的半致死剂量。结果表明,孤生殖海带长度在0.5-1.5cm时,氯霉素的半致死剂量与海带的长度相关,而潮霉素的半致死剂量怀长度不相关。孤雌生殖海地潮霉互比对氯霉素更敏感,提示潮霉素磷酸转移麦基因有可能成为工程的另一个选择标记。  相似文献   

5.
无机氮和磷对海带配子体生长发育的影响   总被引:3,自引:0,他引:3  
氮(N)是蛋白质和核酸等重要有机物的成份。磷(P)是核酸等重要有机物的成份。它们在细胞代谢中发生重要的作用。海带或其他生物在代谢过程中都必须有一定数量的氮和磷的供应,才能正常地生长和发育。Drew(1910)的实验指出,在天然海水中加入一些无机盐的氮和磷可以促进糖海带配子体的生长,  相似文献   

6.
海带类的工业利用在国外从17世纪末就开始,19世纪中叶起陆续出现了一些综合利用的方法。近20年来在这方面进行研究工作较多的国家有日本、英国、苏联等。 近几年来,我国由于大力开展了海带的人工养殖,产量猛增,为工业利用提供了必要的基础。我们在研究了海带综合利用中的两个关键性问题一一原料处理和主产品褐藻酸的提取条件——之后,接着开始了综合利用方法的研究。 国外所研究的海带综合利用要点和缺点大致是: 1. 从同一份海带中综合考虑的产品大多是褐藻酸、碘和甘露醇,而很少同时考虑氯化鉀、褐藻淀粉等其他产品; 2. 水溶性成分是用稀酸提取,这不仅消耗酸和中和用碱,而且对褐藻酸会带来很不利的影响; 3. 甘露醇和碘的分离也各有不同:高桥等推荐用铜沉淀法;英国则直接用酒精从海藻中提取甘露醇,或从稀酸提取液中加有机药品制成水不溶性甘露醇衍生物。前者所需铜盐量相当大,且对于氯化鉀、褐藻淀粉的分离研究不利;后者直接以酒精煮沸海藻,必将显著减低褐藻酸粘度,而水不溶性甘露醇沉淀的制备则成本太高,无多大实用价值。 我们认为,要寻求一个较全面、合理、轻济、简易的综合利用流程,首先应考虑: 1. 各种成分如褐藻酸、甘露醇、碘、氯化鉀、褐藻淀粉等的全面利用的流程; 2. 以水代替稀酸作提取剂;同时确定各种产品的适宜分离条件等。 综合利用流程的初步轮廓和结果已于1959年初提出。其后至1960年初这段时间内,我们对于各产品的分离条件和在各步骤中的产率等方面作了比较系统的进一步实验,并且对于先前提出的流程作了部分修正、补充。  相似文献   

7.
汞是熟知的毒物(Bidwell 1979)。近二十年来随着工业的发展,海洋重金属的污染在世界许多海区已有发现.关于生物对汞、镉、铅等重金属的吸收、积累和代谢过程,常因生物种类、体重、性别等不同而有差异。如紫贻贝(Mytilus edulis)  相似文献   

8.
硒对钝顶螺旋藻生长的影响及其在细胞中的积累和分布   总被引:7,自引:0,他引:7  
《台湾海峡》1998,17(4):432-438
  相似文献   

9.
本研究采用海带孢子体幼苗为实验材料,分别用不同浓度的As(Ⅲ)和As(Ⅴ)(0.2、0.4、0.8、1.6μmol/L)培养液进行循环水养殖,以研究不同价态无机砷在海带中的积累以及对其抗氧化防御系统的影响。结果表明,高浓度砷暴露组中海带总砷含量较高,As(Ⅲ)暴露下海带中总砷含量随时间增加,在28 d时达到最大值;As(V)暴露下海带中总砷含量则呈先升高后下降的趋势,但28 d时除最高浓度组外均显著高于初始值(P<0.05)。实验结束时As(V)暴露组海带中总砷含量显著低于As(Ⅲ),说明无机砷暴露下海带孢子体幼苗对亚砷酸盐的积累大于砷酸盐。无机砷暴露下海带中过氧化氢(H2O2)和丙二醛(MDA)含量随时间的延长分别呈先降低后升高和先降低后升高再降低的趋势,但所有处理组海带中H2O2和MDA含量均显著高于对照组(P<0.05),且随浓度的升高而升高。细胞中过氧化氢酶(CAT)活性在砷暴露下升高,但随暴露时间的延长,无机砷对酶活性产生了一定程度的抑制作用,酶活性降低。超氧化物歧化酶(SOD...  相似文献   

10.
EPA,DHA的提取和生物转化技术   总被引:3,自引:0,他引:3  
近年来,海产鱼油中所含ω-3型高度不饱和脂肪酸对人类健康具有重要的意义。其特征性多烯酸有二十碳五烯酸(Eicosapentaenoic acid,EPA)和二十二碳六烯酸(Docosahexaenoic acid,DHA)。国内外学者为开发EPA、DHA资源,加工和应用这一宝贵营养素,已取得了不少进展。这两种高度不饱和脂肪酸都属于ω-3型,具有很高的生理活性,其主要生理功能是  相似文献   

11.
Ecklonia maxima dominates kelp beds on the west coast of southern Africa, and is commercially and ecologically valuable. Some plants lose all their secondary blades (fronds), leaving only the gas-filled bulb and short primary blade at the top of the stipe. These ‘bald’ kelps may persist for months or longer, occupying substratum space but contributing little to productivity. We investigated natural causes of balding in five kelp beds in False Bay, South Africa, and the effect of simulated commercial frond-harvesting on loss of fronds. Densities of sporophytes with and without fronds were measured at the water surface during low tides. Generalised linear modelling analysis showed a significant relationship between balding and site (whether sheltered from or exposed to swell/wind), position in the kelp bed (shoreward or seaward) and total E. maxima density. We conclude that balding is caused mainly by drying of meristematic basal regions of fronds during emersion of kelp heads at low tide. After partial harvesting of fronds, kelp heads floated higher out of the water, but after 95 days frond loss was significantly higher only when fronds were cut too close to the primary blade, possibly because of damage to meristematic tissue. Nevertheless, increased emersion that results from frond-harvesting may increase desiccation and blade loss and we suggest caution in setting harvest limits for this kelp.  相似文献   

12.
Kelp holdfasts are highly reticulated structures which host a large diversity of small fauna. These microhabitats have been reported to play a crucial role in the biodiversity associated to kelp forest ecosystems. This study aimed at identifying trophic links and the main food sources sustaining food webs within communities associated with kelp holdfasts, through a stable isotope (δ13C and δ15N) approach. Sampling of the main invertebrates inhabiting Laminaria digitata holdfasts, and of their potential food sources, took place in February and May 2007. Stable isotope results reveal that most of the primary consumers, including filter-feeders and deposit-feeders, rely on the particulate organic matter sedimented within kelp holdfasts. Only three grazers departed from this general pattern. The correspondence between the stable isotope ratios of predators and sediment consumers indicated that this source is at the base of the main pathway through which energy and matter transit in the food web. δ15N ranges found for consumers revealed that the food web associated with kelp holdfasts is composed of 3.5 levels. In spite of the low diversity of food sources at the base of the food web, these microhabitats can therefore be considered micro-scale ecosystems, from a functional perspective.  相似文献   

13.
硒对钝顶螺旋藻生长的影响及其在细胞中的累积和分布   总被引:6,自引:0,他引:6  
本文研究了硒对纯顶螺旋藻(Spirulinaplatensis)生长的影响及其在细胞生化组成中的分布。结果表明,当硒浓度低于50mg/dm3时,对钝顶螺旋藻生长的抑制作用不明显,在低浓度下(<10mg/dm3)可促进其生长;当硒浓度超过50mg/dm3时则起抑制作用,高浓度对藻体起毒害作用。藻细胞中总硒含量与培养液中的硒浓度有关,在0~40mg/dm3范围内,硒含量随着培养液中硒浓度的增加而增加:从0mg/dm3的2.50×10-5(m/m,dw)到40mg/dm3的231.45×10-6(m/m,dw),至50mg/dm3,又开始降低为174.26×10-6(m/m,dw);硒在S.platensis生化组成中的分布,以蛋白质含量为最高,可达总硒的49.22%~71.49%,而脂类及碳水化合物-氨基酸中的含量则较低,分别为总硒含量的3.59%~6.18%和1.45%~2.56%,硒在各组成中的含量与培养液中的硒浓度有关,其变化趋势与总硒含量的一致。  相似文献   

14.
The weekly integrals of underwater photon flux density were measured for a two and a half year period in a southern California kelp forest. Photon flux densities were lowest from January to April and peaked in summer. On average, about 2% of the surface irradiation reached the bottom (depth of 13·2 m in an area without a kelp canopy). Photon flux densities under a canopy of giant kelp were reduced by 70% compared to a nearby site cleared of kelp. A significant portion of temporal variability in underwater photon flux density was explained by vertical sediment flux. Surface irradiation did not contribute significantly to the variance in weekly values of underwater irradiation.  相似文献   

15.
The most important marine coastal ecosystem in the Chilean coast are kelp forests. This review is based on ecological studies regarding different aspects of subtidal kelp ecosystems along the Chilean coast. It highlights the most interesting findings in (1) biology of subtidal kelp in Chile, with particular reference to (2) habitats formed by kelp, and considered the successful examples and promising results in the (3) kelp as an industrial resource (Biotechnological approach of kelps and aquaculture). The impact caused by (4) El Ni?o-Southern Oscillation is discussed as an important climatic event that could help to forecast the future of the kelp ecosystem. In addition, this literature review outlines the knowledge gaps on subtidal kelp along the Southeast Pacific Coast of Chile, so that research can be strengthened in the future.  相似文献   

16.
利用无腥味发酵优良的乳酸菌褐藻(海带)凝固奶,进行糖酸配比及添加稳定剂的正交设计试验,确定搅拌型褐藻奶饮料的最佳配比为凝固奶30%、蔗糖10%、酸味剂0.25%、复合稳定剂0.25%。采用科学的工艺生产,并对产品营养成分进行分析,结果表明,褐藻乳酸菌发酵奶是一种风味好、营养价值高、具有保健功能的饮料。  相似文献   

17.
The distribution of species is shifting in response to recent climate change. Changes in the abundance and distributions of habitat‐forming species can have knock‐on effects on community structure, biodiversity patterns and ecological processes. We empirically examined temporal changes in the abundance of the warm‐water kelp Laminaria ochroleuca at its poleward range edge in the Western English Channel. Resurveys of historical sites indicated that the abundance of L. ochroleuca has increased significantly in recent decades. Moreover, examination of historical records suggested that L. ochroleuca has extended its distribution from sheltered coasts on to moderately wave‐exposed open coasts, where it now co‐exists and competes with the assemblage dominant Laminaria hyperborea. Proliferation of L. ochroleuca at its poleward range edge corresponds with a period of rapid warming in the Western English Channel. Preliminary comparisons between L. ochroleuca and L. hyperborea highlighted some subtle but ecologically significant differences in structure and function. In summer, the average biomass of epiphytic stipe assemblages on L. hyperborea was 86 times greater than on L. ochroleuca whereas, on average, L. ochroleuca had a greater stipe length and its blade supported 18 times as many gastropod grazers (Gibbula cineraria). Differences in summer growth rates were also recorded, with L. ochroleuca being more productive than L. hyperborea throughout July. Comprehensive seasonally replicated comparisons are needed to examine the wider implications of proliferation of L. ochroleuca at its poleward range edge, but our study suggests that local biodiversity patterns and ecological processes (e.g. timing of productivity and trophic pathways) on shallow subtidal reefs may be altered by shifts in the relative abundances of habitat‐forming kelp species.  相似文献   

18.
海带育苗过程光照强度监测系统的设计与实现   总被引:1,自引:0,他引:1  
海带(Laminaria japonica)是一种重要的食用藻类,在其生产过程中,育苗是最基础的环节。在海带育苗过程中光照强度因其变化性强、对幼苗影响显著等特点,被看作是一个重要监测指标。针对目前海带育苗光照强度监测方式落后、准确度和效率低的问题,本文基于相关研究成果,设计了一套由Wi-Fi通信和无线局域网加互联网通信方式组成的海带育苗光照强度监测系统。系统以移动客户端应用为主要业务控制中心,依据光照强度传感器、气象工作站等设备获取海带育苗车间内的光照情况以及外部环境参数,通过无线网关节点实现育苗环境信息和远程服务器的信息交换。通过开发系统应用层,实现移动设备客户端远程监控海带育苗光照参数的变化。实际的模拟生产测试表明,该系统性能稳定,实时监测、警报功能达到使用要求,提升了海带育苗生产的信息化水平,可对推动海带等藻类的精准养殖提供一定的参考。  相似文献   

19.
20.
Ecosystem effects of fishing in kelp forest communities   总被引:6,自引:0,他引:6  
  相似文献   

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