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41.
42.
藻类功能食品的物质基础与研究开发现状 总被引:3,自引:0,他引:3
对藻类功能食品的研究和开发现状作综述报道。涉及的主要内容有:作为功能食品物质基础的食物纤维、PUFA、维生素、矿物质和微量元素、氨基酸以及其它有生理活性的物质。 相似文献
43.
Dynamics and Variability of Terra Nova Bay Polynya 总被引:1,自引:0,他引:1
Giannetta Fusco Daniela Flocco Giorgio Budillon Giancarlo Spezie Enrico Zambianchi 《Marine Ecology》2002,23(S1):201-209
Abstract. We present a process study on the dynamics and variability of the Terra Nova Bay polynya in the western sector of the Ross Sea. The air-sea heat exchange is known to be particularly large in polynya during the winter, when differences between air and sea temperatures are large. We apply a 1-D model (Pease, 1987; Van Woert, 1999a, 1999b), which is modified in the latent heat parameterisation in order to account for time-dependent relative humidity and cloud coverage. Furthermore, the Ice Collection Depth is correlated linearly with a variable wind speed. The model is forced with two different meteorological data sets: the operational analysis of the European Center for Medium Range Weather Forecasts atmospheric data set and the meteorological parameters measured by an Automatic Weather Station located on the coast of Terra Nova Bay. The results are compared in terms of polynya extension, ice, and High Salinity Shelf Water production. According to the two different wind velocities, the results obtained from the different data sets clearly differ. Qualitatively, however, the results are in good agreement. 相似文献
44.
几种红藻和蓝藻的光合作用色素 总被引:2,自引:0,他引:2
分离纯化出几种海产红藻和一种蓝藻的光合作用色素,并测定了它们的化学性质和光谱学性质。这些藻类是3种红藻:多管藻(Polysiphonia urceolata)、橡叶藻(Phycodrys sp.)和条斑紫菜(Porphyra yezoensis);蓝藻:钝顶螺旋藻(Spirulina platensis)。用羟基磷灰石柱层析法从上述藻类中分离到几种不同的藻胆蛋白。经SDS-PAGE及光谱测定,发现条斑紫菜中的藻红蛋白不同于其它两种红藻。而橡叶藻中存在的两条藻红蛋白也有差异,条斑紫菜和钝顶螺旋藻中的两种别藻蓝蛋白之间也有区别。叶绿素分析表明,钝顶螺旋藻中叶绿素a的含量高于红藻中叶绿素a的含量。 相似文献
45.
刘剑华 《中国海洋大学学报(自然科学版)》1996,(1)
根据1957~1987年期间采自浙江和福建沿岸的仙菜科海藻标本,初步鉴定有7属14种。分两次报道,首先报道其中的5屑7种:复羽多孢藻Pleonosporiumvenustissimum、日本对丝藻Antithamnionnipponicum和卡洛绢丝藻Callithamnioncallophyllidicola为我国首次较全面描述和绘图记录;赫勒对丝藻Antithamnionhubbsii为浙、闽海域首次报道;而如下三个种纵胞藻Centrocerasclavulatum、日本凋毛藻Griffithsiajaponica和对公藻Antithammioncruciatum在浙、闽海区早有报道。 相似文献
46.
Donald L. Forbes George S. Parkes Gavin K. Manson Lorne A. Ketch 《Marine Geology》2004,210(1-4):169-204
Storms play a major role in shoreline recession on transgressive coasts. In the southern Gulf of St. Lawrence (GSL), southeastern Canada, long-term relative sea-level rise off the North Shore of Prince Edward Island has averaged 0.3 m/century over the past 6000 years (>0.2 m/century over 2000 years). This has driven long-term coastal retreat at mean rates >0.5 m/a but the variance and details of coastal profile response remain poorly understood. Despite extensive sandy shores, sediment supply is limited and sand is transferred landward into multidecadal to century-scale storage in coastal dunes, barrier washover deposits, and flood-tidal delta sinks. Charlottetown tide-gauge records show mean relative sea-level rise of 3.2 mm/a (0.32 m/century) since 1911. A further rise of 0.7±0.4 m is projected over the next 100 years. When differenced from tidal predictions, the water-level data provide a 90-year record of storm-surge occurrence. Combined with wind, wave hindcast, and sea-ice data, this provides a catalogue of potentially significant coastal storms. We also document coastal impacts from three recent storms of great severity in January and October 2000 and November 2001. Digital photogrammetry (1935–1990) and shore-zone surveys (1989–2001) show large spatial and temporal variance in coastal recession rates, weakly correlated with the storm record, in part because of wave suppression or coastal protection by sea ice. Large storms cause rapid erosion from which recovery depends in part on local sand supply, but barrier volume may be conserved by washover deposition. Barrier shores with dunes show high longshore and interdecadal variance, with extensive multidecadal healing of former inlet and overwash gaps. This reflects recovery from an episode of widespread overwash prior to 1935, possibly initiated by intense storms or groups of storms in the latter half of the 19th century. With evidence from the storms of 2000–2001, this points to the importance of storm clustering on scales of weeks to years in determining erosion vulnerability, as well as the need for a long-term, large-scale perspective in assessing coastal stability. The expected acceleration in relative sea-level rise, together with projections of increasing storm intensity and greatly diminished winter ice cover in the southern GSL, implies a significant increase in coastal erosion hazards in future. 相似文献
47.
食用海藻对肠道菌群及肠道微环境影响的研究 总被引:2,自引:0,他引:2
综述了食用海藻对大鼠盲肠肠道菌群及肠道微环境的影响。大鼠喂食添加紫菜等 9种食用海藻的饲料后 ,均能对其盲肠微生物区系及代谢产物和血清脂质水平产生不同的影响 :使肠道中的双歧杆菌数量增加 ,p H值降低 ;抑制血清甘油三酯及血清游离脂肪酸含量。从而改善肠内的生态环境 相似文献
48.
北极气候系统正在发生显著变化,其中,海冰面积和厚度的减小是其最主要的特征.楚科奇海是海冰面积变化最有代表性的区域.文章利用积累了9a的高分辨率海冰分布数据研究海冰面积的多年变化特征.结果表明,各年的冰情有显著的季节内变化,海冰面积距平曲线体现了不同时期海冰面积变化的动态过程.在1997~2005年间,楚科奇海海冰面积经历了轻(1997年)-重(2000~2001年)-轻(2002~2005年)的变化过程.9a的数据总体上体现了海冰面积减小的趋势,2005年的冰情呈现了历史新低.每年融冰期的长短与冰情轻重有密切的关系,冰轻年份融冰开始时间早,冻结结束时间晚.各年海冰面积最小值发生在9月下旬至10月初,各个年份海冰最小面积差别很大.有的年份只有4%,而重冰年可以大于50%.文章采用4个重要参数表达海冰多年变化.其中海冰面积指数反映了当年总体平均的海冰面积距平;海冰最小面积反映了融冰期海冰的极限情况;上一个冬季的气温积温也与翌年海冰面积有良好的关联;分析了风场对海冰的影响,表明风场在融冰期能够在短时间内改变海冰的覆盖面积. 相似文献
49.
本文利用最大熵谱分别计算了南极4个区海冰和西北太平洋台风发生频数的变化周期,并对前3年的南极海冰强弱和当年的台风发生频率数进行了逐月时间序列相关分析。 相似文献
50.
Tsuneo Odate Toru Hirawake Atsushi Tanimura Mitsuo Fukuchi 《Journal of Oceanography》2000,56(2):185-196
Surface temperature, salinity, concentrations of silicate (Si) and nitrate + nitrite (N), and in vivo fluorescence (Fluor) were investigated in the marginal ice zone (MIZ) and the seasonally open oceanic zone (SOOZ) (32–40°E, 64–69°S) from February 23 to 28 1992. In the MIZ the mean Si and N were 67.8 ± 2.2 M and 32.5 ± 1.7 M, respectively. There was a trend that low N values coincided with high Fluor values. Observation conducted at one point (64°S, 38°E) revealed a diel variation pattern in Fluor. Applying this pattern of deviation from noon value, all Fluor data were normalized to value at local noon. In the MIZ a significant negative correlation was observed between the normalized Fluor and N but not Si. On the other hand, Si decreased continuously from south to north in the SOOZ and was negatively correlated with the normalized Fluor. Difference in Si concentration was about 30 M between the sea around 64°S and the MIZ, while the difference in N concentration was estimated as less than 10 M. If diatoms take up silicate and nitrogen at an approximate ratio of 1:1, additional nitrogenous nutrients other than nitrate and nitrite (e.g. ammonia, urea etc.) would be required. In this case, an f-ratio of lower than 33% is obtained. It is suggested that in the MIZ abundance of phytoplankton community dominated by non-diatom increases utilizing nitrate while in the SOOZ abundance of phytoplankton community dominated by diatoms increases consuming Si and regenerated nitrogen. 相似文献