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81.
为了解大型海藻养殖对海水DO含量的影响,明确其在光照、黑暗及光暗交替条件下海水DO含量的变化过程。笔者将取自温州洞头近海养殖的鼠尾藻、羊栖菜带至实验室内进行养殖实验,设置光照(2、6、12 h)、黑暗(2、6、12 h)、光暗交替(1 h 1 h、6 h 6 h、12 h 12 h)处理,测定养殖水体DO含量,对其产氧速率、耗氧速率等进行分析。结果表明:随着光照时间的延长,鼠尾藻、羊栖菜产氧速率都逐渐下降,鼠尾藻的产氧速率比羊栖菜高(P<0.05);黑暗条件下,鼠尾藻耗氧速率在6 h时达最高288.02 mg/kg DW?h,羊栖菜耗氧速率在2 h时达最高207.46 mg/kg DW?h,鼠尾藻的耗氧速率比羊栖菜高;光暗交替下鼠尾藻的净产氧速率先急剧降低后缓慢升高,短光暗交替周期(1 h 1 h)时净产氧速率最高457.08 mg/kg DW?h。羊栖菜净产氧速率先升高后降低,在中光暗交替周期(6 h 6 h)时最高64.04 mg/kg DW?h。大型海藻养殖时随着光暗环境的交替进行,不断发生着光合产氧、暗呼吸耗氧的转换,总体而言海藻养殖提高了水体DO含量。大型海藻养殖的生态、社会价值显著,建议大力推广 相似文献
82.
Although soil algae are among the main primary producers in most terrestrial ecosystems of continental Antarctica, there are very few quantitative studies on their relative proportion in the main algal groups and on how their distribution is affected by biotic and abiotic factors. Such knowledge is essential for understanding the functioning of Antarctic terrestrial ecosystems. We therefore analyzed biological soil crusts from northern Victoria Land to determine their pH, electrical conductivity (EC), water content (W), total and organic C (TC and TOC) and total N (TN) contents, and the presence and abundance of photosynthetic pigments. In particular, the latter were tested as proxies for biomass and coarse-resolution community structure. Soil samples were collected from five sites with known soil algal communities and the distribution of pigments was shown to reflect differences in the relative proportions of Chlorophyta, Cyanophyta and Bacillariophyta in these sites. Multivariate and univariate models strongly indicated that almost all soil variables (EC, W, TOC and TN) were important environmental correlates of pigment distribution. However, a significant amount of variation is independent of these soil variables and may be ascribed to local variability such as changes in microclimate at varying spatial and temporal scales. There are at least five possible sources of local variation: pigment preservation, temporal variations in water availability, temporal and spatial interactions among environmental and biological components, the local-scale patchiness of organism distribution, and biotic interactions. 相似文献
83.
水生藻类的环境指示作用 总被引:3,自引:1,他引:2
为了方便有效地监测水环境中有氮磷污染物、重金属、农药及其他有机污染物等,笔者研究了水生藻类对水体环境中相应污染物的敏感性和耐受性,以及污染物对水域生态系统中藻类种群结构所造成的影响,分析了污染物对水生藻类的毒理和富集等,获得了大量数据。结果表明,水生藻类对一些水环境污染物具有较好的指示作用,该方法便于直观快速地调查分析相应水体的污染情况。 相似文献
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The development and use of topical microbicides potentially offers an additional strategy to reduce the spread of the Human Immunodeficiency Virus (HIV). Carbohydrate-binding agents (CBAs) that show specificity for high mannose carbohydrates on the surface of the heavily glycosylated envelope of HIV are endowed with potent anti-HIV activity. In fact, a number of algal lectins such as cyanovirin-N, microvirin, microcystis viridis lectin, scytovirin, Oscillatoria agardhii agglutinin and griffithsin are considered as potential microbicide candidates to prevent the sexual transmission of HIV through topical applications. They not only inhibit infection of cells by cell-free virus but they can also efficiently prevent virus transmission from virus-infected cells to uninfected CD4(+) target T-lymphocytes and DC-SIGN-directed capture of HIV-1 and transmission to CD4(+) T lymphocytes. This review focuses on the structural properties and carbohydrate specificity of these algal lectins, their antiviral activity against HIV and several other enveloped viruses, their safety profile and viral resistance patterns. 相似文献
88.
Je-Hyuk Lee 《Journal Of Aquatic Food Product Technology》2013,22(3):227-240
Among 51 marine algae distributed along the Korean coast, Sargassum muticum (Yendo) Fensholt, Ishige okamurae Yendo, Ecklonia cava Kjellman, Polysiphonia morrowii Harvey, Dictyopteris undulata Holmes, Sargassm micracanthum (Kutzing) Endlicher, and Sargassum macrocarpum C. Agarch were found to have potent antioxidant activity. Additionally, the reducing power of marine algae-extracts was consistent with diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity. Because little is known about Sargassum muticum (Yendo) Fensholt, Ishige okamurae Yendo, Ecklonia cava Kjellman, Polysiphonia morrowii Harvey, Dictyopteris undulata Holmes, Sargassm micracanthum (Kutzing) Endlicher, and Sargassum macrocarpum C. Agarch, these marine algae may act as candidates for potent antioxidant food materials and are expected to have functional activity for foods and pharmaceuticals for treating oxidative diseases. 相似文献
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